(19)
(11)EP 0 631 352 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
06.10.1999 Bulletin 1999/40

(21)Application number: 94301753.3

(22)Date of filing:  11.03.1994
(51)Int. Cl.6H01R 23/70, F16B 17/00

(54)

Electrical connector mounting posts

Montageteile für elektrische Verbinder

Organes de montage pour connecteur électrique


(84)Designated Contracting States:
BE CH DE ES FR GB IT LI LU NL SE

(30)Priority: 12.03.1993 US 30528

(43)Date of publication of application:
28.12.1994 Bulletin 1994/52

(73)Proprietor: THOMAS & BETTS CORPORATION (a Tennessee Corporation)
Memphis, Tennessee 38119 (US)

(72)Inventor:
  • Lutsky, Arthur A.
    Orange, California (US)

(74)Representative: Howick, Nicholas Keith et al
CARPMAELS & RANSFORD 43 Bloomsbury Square
London WC1A 2RA
London WC1A 2RA (GB)


(56)References cited: : 
EP-A- 0 366 964
GB-A- 2 082 542
US-A- 3 688 635
DE-A- 2 925 058
GB-A- 2 153 472
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    FIELD OF THE INVENTION:



    [0001] The present invention relates generally to an electrical connector for mounting to a printed circuit board or similar substrate. More particularly, the present invention relates to connector mounting posts which are insertable into holes in the printed circuit board to support the electrical connector thereon. A connector having the features of the preamble of claim 1 is, for instance, known from EP-A-0 366 964.

    BACKGROUND OF THE INVENTION:



    [0002] It has been long known to use mounting posts which extend from an electrical connector to support the connector on a printed circuit board or other substrate to which the electrical connector is to be attached. These mounting posts are insertable into through-holes of the printed circuit board and locate and secure the connector to the printed circuit board prior to permanent connection such as by soldering the electrical contacts of the connector to the printed circuit board.

    [0003] As may be appreciated, the relative positioning of the mounting posts with respect to the through-holes of the printed circuit board is critical in achieving a secure fit between the connector and the printed circuit board. Variations as between the diameter of the through-hole and the diameter of the mounting post could render insertion of the mounting post in the through-hole difficult. The distance between through-holes of the printed circuit board, as it relates to the distance between the mounting posts, is also critical in assuring proper positioning of the connector with respect to the printed circuit board. Even slight variations between the spacing of the through-holes of the printed circuit board and the spacing of the mounting posts could cause significant interference between the posts and the through-holes so as to render insertion difficult.

    [0004] In addition, engagement of the mounting posts with the through-holes of the printed circuit board is designed to be a frictional fit so that the connector is temporarily secured to the printed circuit board prior to soldering the connector contacts to the board. This again adds a further complication which renders proper positioning of the posts with respect to the through-holes difficult.

    [0005] It is, therefore, desirable to provide an electrical connector having mounting posts which facilitate the easy mounting of an electrical connector to a printed circuit board.

    SUMMARY OF THE INVENTION



    [0006] It is an object of the present invention to provide an electrical connector having mounting posts which permit the connector to be easily supported over through-holes of a printed circuit board.

    [0007] It is a further object of the present invention to provide connector mounting posts which will accommodate variations in through-hole size and relative spacing.

    [0008] It is a still further object of the present invention to provide mounting posts for an electrical connector which will securely support the electrical connector on the printed circuit board prior to soldering.

    [0009] In the efficient attainment of these and other objects, the present invention provides an electrical connector for mounting to a printed circuit board with the features of claims 1 and 5.

    [0010] The posts preferably have a diamond-shaped cross-section. The major axis of one mounting post of the electrical connector extends perpendicularly to the major axis of the other mounting post of the electrical connector.

    BRIEF DESCRIPTION OF THE DRAWINGS:



    [0011] Figures 1 and 2 show in a front-plan and bottom views respectively, an electrical connector of the present invention with the central portion broken away.

    [0012] Figures 3 is a side-elevational showing of the electrical connector of Figures 1 and 2.

    [0013] Figure 4 is a greatly enlarged schematic representation of the relationship between the mounting post of the connector of Figure 1 and a through-hole of a printed circuit board.

    [0014] Figures 5 and 6 respectively, show engagement of the mounting post of Figure 1 with relatively differently sized and positioned through-holes.

    [0015] Figure 7 shows through-holes of a printed circuit board into which the mounting posts of the connector of Figure 1 may be inserted.

    DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS:



    [0016] Referring now to Figures 1 - 3, an electrical connector 10 of the present invention is shown. Electrical connector 10 is an elongate rectangular member formed of suitably electrically insulative plastic. Connector 10 includes an upper connection surface 12 for receipt of a mating electrical connector (not shown) and an opposed lower surface 14, which is supported or mounted on a printed circuit board to which the connector is secured in a manner which will be described in further detail hereinbelow.

    [0017] Connector 10 is of conventional construction having a pair of longitudinal opposed sidewalls 16 and 18 defining therebetween a cavity 20, which accommodates therein the mating electrical connector. Each opposed end of electrical connector 10 includes an extending mounting ear 22 which may support appropriate hardware to secure the connector to the printed circuit board as is well-known in the connector art.

    [0018] Electrical connector 10 supports a plurality of electrical contacts 24 therein (Fig. 2). In the present illustrative embodiment, contacts 24 are pin-type contacts which extend through openings 26 in the lower surface 14 of connector 10. While pin-type contacts 24 are shown, it may be appreciated that a variety of contacts, including socket-type contacts, may be employed with the present invention. Typically, contacts 24 are elongate having upper portions 24a, which extend into cavity 20 for electrical engagement with contacts of the mating electrical connector. Contacts 24 also include opposed ends 24b, which extend below lower surface 14 for electrical engagement with traces on the printed circuit board as is conventional in the electrical connector art.

    [0019] Electrical connector 10 further includes a pair of mounting posts 30 and 32, which extend from the lower surface 14 of connector 10. Mounting posts 30 and 32 extend adjacent each end of connector 10 beneath mounting ears 22. Mounting posts 30 and 32 are constructed to be inserted into through-holes 34 and 36 of the printed circuit board 38 (Fig. 7). The lower ends 31 of mounting posts 30 and 32 are tapered to facilitate entry into through-holes 34 and 36 respectively.

    [0020] As shown in Figures 1 - 3, mounting posts 30 and 32 are generally diamond-like in shape, defining a major axis and minor axis transverse thereto. Mounting post 30 is rotated 90° with respect to the position of mounting post 32 so that the respective major and minor axes of the mounting posts are perpendicular to one another. Opposed ends of the major axis define curved apexes 44 for engagement with through holes 34 and 36 of the printed circuit board 38 as will be further described hereinbelow. The opposed ends of the minor axis are constructed for non-engagement with the walls of through-holes 34 and 36. While the present invention shows posts having a pair of curved opposed ends defining the diamond-like shape, other shapes and number of curved portions may also be employed.

    [0021] Referring to Figures 4 - 7, the engagement of mounting posts 30 and 32 with through-holes 34 and 36 of printed circuit board 38 is described.

    [0022] Figure 4 shows, in greatly enlarged schematic fashion, the relationship between the walls of through-hole 34 and mounting post 30, which is inserted thereinto. Through-hole 34 is a substantially circular opening having a radius r1 which defines a given radius of curvature of opening 34. Post 30, more particularly shown in Figures 5 and 6, has an elongated shape having opposed sets of inwardly converging sidewalls 40 and 42 at each end thereof. Each set of sidewalls 40 and 42 converge at curved apex 44, which is constructed for engagement with the wall defining through-hole 34. Curved apex 44 is defined by a radius r2, which is substantially less than radius r1 of through-hole 34. Thus, the radius of curvature of apex 44 is substantially less than the radius of curvature of through-hole 34. As the radius of curvature is the inverse of the curvature of a surface, the curvature of apex 44 is substantially greater than the curvature of through-hole 34. The actual surface contact between apex 44 and walls of through-hole 34 is minimized by the respective curvatures so as to provide minimal interference between apex 44 of mounting post 30 and the wall of through-hole 34. As will be shown with respect to Figures 5 and 6, the particular construction of mounting post 30 permits the accommodation of greater dimensional tolerance as between the size and location of mounting posts 30 and 32 and through-holes 34 and 36.

    [0023] First, the spacing of the through-holes 34 and 36 with respect to mounting posts 30 and 32 may not be identical. Distance s1 between the centers of mounting posts 30 and 32, as shown in Figure 1, may be slightly greater or less than the distance s2 between the centers of through-holes 34 and 36 (Fig. 7). Such misalignment, shown in Figure 5, may be a distance Δ1. In such a situation, the position p1 of mounting post 30 with respect to through-hole 34 is shifted to that of p2 with the major axis of post 30 shifted to the right as shown in Figure 5 a distance Δ1. Since the radius of curvature of apex 44 (Fig. 4) at each end of the major axis is substantially less than the radius of curvature of the wall of through-hole 34 and, therefore, the curvature of each apex 44 is substantially greater than the curvature of through-hole 34, interference between apex 44 and the wall of through-hole 34 is minimal notwithstanding the relative positional shift of post 30 with respect to through-hole 34 from position p1 to position p2. Thus, even a relatively significant offset as between post 30 and through-hole 34 will result in only a minimal increase in interference between each apex 44 and the wall of through-hole 34. This permits mounting posts to be more tolerant of variances as between distance s1 of posts 30 and 32 and distance s2 of through-holes 34 and 36.

    [0024] Additionally, as shown in Figure 6, the present invention compensates for dimensional variation as between relative diameter d1 of through-hole 34 and the length of major axis d2 of mounting post 30. In certain situations, mounting post 30 may have a major axis d2, which is slightly greater than the diameter d1 of through-hole 34. As both sets of tapered sidewalls 40 and 42 merge to form a curved apex 44 at each end of the major axis, a minimal increase in the interference as between the wall of through-hole 34 and each curved apex 44 will occur.

    [0025] The walls 40 and 42 taper sharply inwardly toward apex 44. Further, as described above with respect to Figure 4, the curvature of apex 44 is substantially greater than the curvature of through-hole 34. Thus, minimum interference occurs therebetween even in situations where d2 exceeds d1 as shown in Figure 6. Ideally, mounting post 30 is designed to have a major axis length d1 which is identical to the diameter of through-hole 34, d2 i.e. d1=d2. However, manufacturing tolerance may cause the major axis d2 of post 30 to exceed the through-hole diameter d1 a slight distance d2 -d1 = Δ2. As the mounting post 30 is self-centering in through-hole 34, one-half of such interference (1/2Δ) will be borne by each opposed apex 44. This interference is relatively minimal and will not significantly increase the difficulty in inserting post 30 into through-hole 34.

    [0026] Still further the present invention provides for accommodating misalignment as between the transverse positioning of the centers of through-holes 34 and 36. As shown in Figure 7, during the manufacture of printed circuit board 38 it is possible that centers of through-holes 34 and 36 may be transversely offset a distance a. Referring to Figure 2, mounting posts 30 and 32 are arranged so that one mounting post 32 has its major axis aligned with the longitudinal direction of connector 10 while the other mounting post 30 has its major axis aligned perpendicularly thereto. In a manner similar to that shown with respect to Figure 5, the transverse offset of through-holes 34 and 36 may be compensated for by the particularly shown construction and arrangement of mounting posts 30 and 32.

    [0027] The present invention, therefore, compensates for dimensional tolerances between mounting post 30 and 32 and through holes 34 and 36 in three respects. First, the construction of posts 30 and 32 compensates for variances between the spacing of through-holes 34 and 36 (s2) and the spacing of posts 30 and 32 (s1). Second, the post construction compensates for variances between the through-hole size (d1) and the size of post 30 (d2). Third, the arrangement of posts 30 and 32 compensates for transverse misalignment of through-holes 34 and 36 (a).

    [0028] Various changes to the foregoing described and shown structures would now be evident to those skilled in the art. Accordingly, the particularly disclosed scope of the invention is set forth in the following claims.


    Claims

    1. An electrical connector (10) for mounting to a printed circuit board (38) comprising:

    an elongate connector housing having first and second connector ends, an upper connection surface and an opposed lower board mounting surface;

    a first mounting post (30) extending from said lower mounting surface adjacent said first connector end; and

    a second mounting post (32) extending from said lower mounting surface adjacent said second connector end;

       characterised in that each of said first and second mounting posts (30,32) have a cross-section having a major axis and a minor axis, each end of said major axis having a curved portion (44) having a radius of curvature which is substantially less than the radius of curvature of a circle having a diameter equal to the length of the major axis of the mounting posts, wherein said first mounting post (30) major axis extends perpendicularly to said major axis of said second mounting post (32).
     
    2. An electrical connector of claim 1 wherein said first and second mounting posts (30,32) have a diamond-shaped cross-section.
     
    3. An electrical connector of claim 1 or claim 2 wherein said ends of said minor axis are constructed for non-engagement with said walls of said opening.
     
    4. An electrical connector of any one of claims 1 to 3 wherein said first and second mounting posts (30,32) have tapered end portions.
     
    5. An electrical connection assembly comprising:

    a printed circuit board (38) having plural circular mounting openings (34,36) therein, said openings having a given radius of curvature;

    an elongate electrical connector (10) supported on the board said connector having a pair of spaced apart mounting posts (30,32), each post positioned in one of said board openings (34,36), each said mounting post (30,32) having curved opening engagement surfaces (44), each said surface having a radius of curvature which is substantially less than said radius of curvature of said opening (34,36), each of said mounting posts including a major axis and a minor axis wherein said first mounting post (30) major axis extends perpendicularly to said major axis of said second mounting post (32).


     
    6. An assembly of claim 5 wherein each said post (30,32) includes a pair of opening engagement surfaces (44).
     
    7. An assembly of claim 6 wherein each said pair of opening engagement surfaces (44), engages diametrically opposite portions of said opening (34,36).
     
    8. An assembly of claim 7 wherein each said post (30,32) has a diamond-shaped cross-section and said curved portions (44) being at opposite ends of the major axis of said diamond.
     
    9. An assembly of claim 8 wherein said connector is elongate having one of said mounting posts (30,32) adjacent each end thereof.
     
    10. An assembly of claim 9 wherein said major axis of one said post (32) extends along the longitudinal extent of said connector (10) and the major axis of said other post (30) extends transverse to said longitudinal extent of said connector (10).
     


    Ansprüche

    1. Ein elektrischer Verbinder (10) zur Montage auf einer Leiterplatte (38) bestehend aus:

    einem langgestreckten Verbindergehäuse mit einem ersten und einem zweiten Verbinderende, mit einer oberen Verbindungsoberfläche und einer entgegengesetzt dazu liegenden unteren Plattenmontageoberfläche,

    einem von der unteren Montageoberfläche am ersten Verbinderende ausgehenden ersten Einpreßstift (30) und

    einem von der unteren Montageoberfläche am zweiten Verbinderende ausgehenden zweiten Einpreßstift (32),

    dadurch gekennzeichnet, daß der erste und der zweite Einpreßstift (30, 32) einen Querschnitt mit einer Haupt- und einer Nebenachse aufweisen, jedes Ende der Hauptachse einen bogenförmigen Abschnitt (44) mit einem Krümmungshalbmesser aufweist, der wesentlich unter dem Krümmungshalbmesser eines Kreises mit einem Durchmesser gleich der Länge der Hauptachse der Einpreßstifte liegt, wobei die Hauptachse des ersten Einpreßstiftes (30) senkrecht zu der Hauptachse des zweiten Einpreßstiftes (32) verläuft.
     
    2. Ein elektrischer Verbinder nach Anspruch 1, wobei der erste und der zweite Einpreßstift (30, 32) rautenförmigen Querschnitt aufweisen.
     
    3. Ein elektrischer Verbinder nach Anspruch 1 oder Anspruch 2, wobei die Enden der Nebenachse zur Nichtanlage an den Wänden der Öffnung konstruiert sind.
     
    4. Ein elektrischer Verbinder nach irgendeinem der Ansprüche 1 bis 3, wobei der erste und der zweite Einpreßstift (30, 32) sich verjüngende Endabschnitte aufweisen.
     
    5. Eine elektrischer Verbindungsanordnung bestehend aus:

    einer Leiterplatte (38) mit mehreren kreisförmigen Montagebohrungen (34, 36) mit einem gegebenen Krümmungshalbmesser,

    einem auf der Platte getragenen langgestreckten elektrischen Verbinder (10) mit zwei auseinanderliegenden Einpreßstiften (30, 32), wobei jeder Stift in einer der Plattenbohrungen (34, 36) angeordnet ist, jeder Einpreßstift (30, 32) bogenförmige Bohrungsanlageflächen (44), jede Fläche einen Krümmungshalbmesser, der wesentlich unter dem Krümmungsradius der Bohrung (34, 36) liegt, und jeder Einpreßstift eine Haupt- und eine Nebenachse aufweist, wobei die Hauptachse des ersten Einpreßstiftes (30) senkrecht zu der Hauptachse des zweiten Einpreßstiftes (32) verläuft.


     
    6. Eine Anordnung nach Anspruch 5, wobei jeder Stift (30, 32) zwei Bohrungsanlageflächen (44) aufweist.
     
    7. Eine Anordnung nach Anspruch 6, wobei beide Bohrungsanlageflächen (44) an diametral gegenüberliegenden Abschnitten der Bohrungen (34, 36) anliegen.
     
    8. Eine Anordnung nach Anspruch 7, wobei jeder Stift (30, 32) einen rautenförmigen Querschnitt aufweist und die bogenförmigen Abschnitte (44) an einander entgegengesetzten Enden der Hauptachse der Raute liegen.
     
    9. Eine Anordnung nach Anspruch 8, wobei der Verbinder langgestreckt ist und einer der Einpreßstifte (30, 32) an jedem seiner Enden angeordnet ist.
     
    10. Eine Anordnung nach Anspruch 9, wobei die Hauptachse des einen Stiftes (32) entlang der Längserstreckung des Verbinders (10) und die Hauptachse des anderen Stiftes (30) quer zu der Längserstreckung des Verbinders (10) verläuft.
     


    Revendications

    1. Connecteur électrique (10) destiné à être monté sur une carte à circuit imprimé (38) comprenant :

    un boîtier allongé de connecteur comportant des première et seconde extrémités de connecteur, une surface supérieure de connexion et une surface inférieure opposée de montage sur la carte,

    un premier tenon de montage (30) s'étendant à partir de ladite surface inférieure de montage à proximité de ladite première extrémité de connecteur, et

    un second tenon de montage (32) s'étendant à partir de ladite surface inférieure de montage à proximité de ladite seconde extrémité de connecteur,

       caractérisé en ce que chacun desdits premier et second tenons de montage (30, 32) présente une section transversale comportant un grand axe et un petit axe, chaque extrémité dudit grand axe comportant une partie incurvée (44) présentant un rayon de courbure qui est sensiblement inférieur au rayon de courbure d'un cercle dont le diamètre est égal à la longueur du grand axe des tenons de montage, dans lequel ledit grand axe du premier tenon de montage (30) s'étend perpendiculairement audit grand axe dudit second tenon de montage (32).
     
    2. Connecteur électrique selon la revendication 1, dans lequel lesdits premier et second tenons de montage (30, 32) présentent une section transversale en forme de losange.
     
    3. Connecteur électrique selon la revendication 1 ou la revendication 2, dans lequel lesdites extrémités dudit petit axe sont conçues de façon à ne pas venir en prise avec lesdites parois de ladite ouverture.
     
    4. Connecteur électrique selon l'une quelconque des revendications 1 à 3, dans lequel lesdits premier et second tenons de montage (30, 32) présentent des parties d'extrémité effilées.
     
    5. Ensemble de connexion électrique comprenant :

    une carte à circuit imprimé (38) comportant plusieurs ouvertures de montage circulaires (34, 36) dans celle-ci, lesdites ouvertures présentant un rayon de courbure donné,

    un connecteur électrique allongé (10) supporté sur la carte, ledit connecteur comportant une paire de tenons de montage espacés (30, 32), chaque tenon étant positionné dans l'une desdites ouvertures (34, 36) de la carte, chaque dit tenon de montage (30, 32) présentant des surfaces incurvées (44) de venue en prise avec l'ouverture, chaque dite surface présentant un rayon de courbure qui est sensiblement inférieur auxdits rayons de courbure de ladite ouverture (34, 36), chacun desdits tenons de montage comprenant un grand axe et un petit axe, chaque extrémité dudit grand axe présentant une partie incurvée (44) comportant un rayon de courbure qui est sensiblement inférieur au rayon de courbure d'un cercle dont le diamètre est égal à la longueur du grand axe des tenons de montage, dans lequel ledit grand axe du premier tenon de montage (30), s'étend perpendiculairement audit grand axe dudit second tenon de montage (32).


     
    6. Ensemble selon la revendication 5, dans lequel chaque dit tenon (30, 32) comprend une paire de surfaces (44) de venue en prise avec l'ouverture.
     
    7. Ensemble selon la revendication 6, dans lequel chaque dite paire de surfaces (44) de venue en prise avec l'ouverture, vient en prise avec des parties diamétralement opposées de ladite ouverture (34, 36).
     
    8. Ensemble selon la revendication 7, dans lequel chaque dit tenon (30, 32) présente une section transversale en forme de losange, et lesdites parties incurvées (44) se trouvent à des extrémités opposées du grand axe dudit losange.
     
    9. Ensemble selon la revendication 8, dans lequel ledit connecteur est allongé, comportant l'un desdits tenons de montage (30, 32) à proximité de chaque extrémité de celui-ci.
     
    10. Ensemble selon la revendication 9, dans lequel ledit grand axe d'un premier tenon (32) s'étend suivant l'étendue longitudinale dudit connecteur (10) et le grand axe dudit autre tenon (30) s'étend transversalement à ladite étendue longitudinale dudit connecteur (10).
     




    Drawing