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(11) | EP 0 002 114 B1 |
| (12) | EUROPEAN PATENT SPECIFICATION |
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Zero insertion force printed circuit board edge connector Reibungsfrei einsetzbarer Kantenverbinder fÜr gedruckte Schaltungsplatten Connecteur en bordure pour cartes à circuits imprimés à force d'insertion nulle |
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| 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). |
[0001] There is described in DE A 2,207,122, a zero insertion force printed circuit board edge connector, comprising an insulating housing having a channel therein for receiving a printed circuit board along a board insertion path, a row of electrical contacts positioned on each side of the channel and extending in a longitudinal direction thereof, each contact having a contact surface for engaging the printed circuit board when such has been inserted into the channel, and contact-operating means comprising a cam mean movable to displace a contact driving means in the direction in which the board insertion path extends, to move each contact between a board receiving first position in which the contact surface of the contact is withdrawn from the board insertion path and a board engaging second position in which such contact surface intersects the board insertion path, the contact-operating means being formed with relatively stepped surfaces succeeding one another in the longitudinal direction of the channel so that the contacts are moved sequentially between their first and second positions, in response to the movement of the cam means.
[0002] In this known connector, the stepped surfaces are provided on the cam means and the contact driving means are in the form of a plurality of contact driving members each of which is engageable with only two opposed contacts of the rows.
[0003] The present invention is intended to provide a connector of the above kind which is substantially simplified in that it has only one contact driving member despite the fact that the connector may comprise a multiplicity of contacts in each row.
[0004] A connector as defined in the first paragraph of this specification is, according to the present invention therefore, characterised in that the relatively stepped surfaces are provided on the contact driving means, these relatively stepped surfaces serving sequentially to engage the contacts of the rows; and in that the contact driving means is in the form of a single contact driving member which comprises a base from opposite edges of which extend side walls, the stepped surfaces being formed in the free longitudinal edges of the side walls, so that the height of each side wall increases in one longitudinal direction of the channel.
[0005] Although according to FR A 2,278,222 beads of different heights may be provided on a contact driving means sequentially to move the contacts of an electrical connector between contact making and contact breaking positions, at least one contact driving member is, and indeed must be, provided for each row of contacts.
[0006] In a connector according to the invention, each stepped surface may be conveniently dimensioned to engage a group of contacts connected to a respective circuit, for example a power circuit, a ground circuit or a signal circuit, whereby these circuits are made and broken sequentially.
[0007] Although there is disclosed in United States Patent Specification No, 3,648,221 a zero insertion force connector which can be programmed by varying the number of contact engaging projections on a cam member of the connector, there is no suggestion in this prior patent specification that the cam member can be arranged sequentially to displace the contacts.
[0008] According to United States Patent Speci- ftcatio'n No. 3,475,717 two rows of contacts of a zero insertion force printed circuit edge connector may be independently driven between board engaging and board disengaging positions. However, all the contacts of each row can be driven only simultaneously between positions.
[0009] The state of the art at this time is further exemplified by United States Patent Specifications Numbers 2,770,788; 3,037,181; 3,366,916; 3,451,490; 3,576,515; 3,744,805; 3,793,609; 3,897,991; 3,889,234; 3,982,807; 4,047,782; 4,076,362 and 4,077,688.
[0010] For a better understanding of the invention reference will now be made by way of example to the accompanying drawings, in which:-
Figure 1 is a perspective view of a sequentially actuable zero insertion force printed circuit board edge connector which embodies the invention, the connector being shown in a board engaging condition;
Figure 2 is a longitudinal vertical section through the connector of Figure 1;
Figure 3 is a top plan view of the connector shown partly in horizontal section, the connector being shown in an intermediate condition;
Figure 4 is a transverse vertical section through the connector with contacts thereof in a closed position;
Figure 5 is a partial transverse vertical section, through the connector with the contacts in an open, board receiving position; and
Figure 6 is a foreshortened perspective view of a contact driving member of the connector.
[0011] The connector comprises four primary components, namely, an elongate insulating housing. 12, a cam member 14, a contact driving member 16, and a plurality of spring electrical contacts 18.
[0012] The housing 12 has mounting flanges 20 and 22 at the opposite ends thereof for securing the connector to a mother printed circuit board 24 by means of fasteners 26 (Figure 2). The housing 12 has formed therein an elongate central guide channel 28 for receiving a daughter circuit board 30, the longitudinal side walls 2 of the housing 12 being formed with spaced ribs 22 projecting inwardly from the side walls 2 and defining recesses 34. Each recess 34, which communicates with the channel 28, receives a respective contact 18. A passage 36 extends from the lower (as seen in Figure 4) end of each recess 34 through a base 38 of the housing 12. The base of the channel 28 is formed with a central longitudinal groove 40 which communicates with a slot 41 in one end of the housing 12 and with an opening 39 in the other end thereof, opposed recesses 42 being formed in the upper (as seen in Figure 1) portions of the side walls of the slot 41 and opening into the upper surface of the housing 12.
[0013] The contact driving member 16, which lies in the channel 28 is, as best seen in Figure 6, channel shaped, having a base 44 and parallel side walls 46 and 48, the free longitudinal edges of the side walls 46 and 48 being formed, as best seen in Figure 6, with steps 49 so that the height of the free longitudinal edges of these side walls increases from right to left, as seen in Figures 2 and 6. These free longitudinal edges, which have chamfered outer faces 47, comprise at least two relatively stepped surfaces succeeding one another in the longitudinal direction of the channel 28. The ends of the base 44 have bevelled surfaces 50 and 52. As shown in Figures 2, 4 and 5, the outer or lower surface of the base 44 faces the mouth of the groove 40.
[0014] The cam member 14 comprises an elongate cam portion 60 and a resilient, loop-shaped, handle 62. The cam portion 60, which is slidably and rotatably received in the groove 40, is shaped, as seen in cross-section (Figures 4 and 5), as an elongate quadrilateral having parattet sides joined by radii. The handle 62, which has a free end portion 64, extends from the cam portion 60 externally of the housing 12, for rotating the cam portion 60 about its longitudinal axis and for sliding the cam portion 60 longitudinally of the groove 40.
[0015] The contacts 18 may be formed for example by stamping and forming metal strips, or by rolling and forming wire. Each contact 18 has a resilient, inwardly bowed, board engaging contact surface 54 and a terminal portion 56 which extends through one of the passages 36 for mechanical and electrical connection to a printed conductor 58 (Figure 2) on the mother board 24 and to further conductors (not shown) and thus to electrical circuits (not shown) by wire wrap connections (not shown), for example. Each contact 18 is retained against withdrawal from the housing by means, for example, of a locking lance (not shown) or by the flow of the housing material during manufacture of the connector, into an aperture (not shown) in the contact 18.
[0016] The free end portion 64 of the handle 62 is receivable in the recesses 42 of the housing, for the avoidance of unintended rotation of, and removal, in the direction of the arrow B in Figure 1, from the connector of, the cam member 14.
[0017] The connector is assembled by inserting the cam portion 60 of the member 14 into the groove 40 and the contact driving member 16 into the channel 28, aided by the bevelled surfaces 50 or 52.
[0018] When the cam portion 60 is positioned as shown in Figures 1, 2 and 4 so that its broader sides 61 lie parallel to the base of the groove 40 and to the base 44 of the driving member 16, the driving member 16 takes up a retracted position so that all the surfaces 54 of the contacts 18 are in a board engaging position, in which they project into the insertion path of the board 30 into the channel 28, as best seen in Figure 4.
[0019] As the handle 62 is rotated in the direction of the arrow A in Figure 3, the cam portion 60 is rotated about its longitudinal axis towards the position of Figure 5 in which the broader sides 61 of the portion 60 extend normally of the base of the groove 40 and of the outer surface of the base 44.
[0020] During such rotation of the handle 62, the driving member 16 is progressively forced by the cam portion 60 in a direction normal to the base of the groove 40 and thus of the base of the channel 28, and away therefrom, so that the chamfered faces 47 of the free longitudinal edges of the side walls 46 and 48 of the driving member 16 sequentially engage respective groups of the contacts 18 to move the contact surfaces 54 thereof outwardly into the recesses 34 and thus into their board receiving positions shown in Figure 5, in which the contact surfaces 54 are withdrawn from the insertion path of the board 30. As shown in Figure 3, the leftward group of contact surfaces, 54a, are first driven into their board receiving positions followed by the next adjacent group of contact surfaces, 54b, and so on in predetermined sequence.
[0021] When all the groups of contact surfaces 54 have thus been moved into their board receiving positions, the daughter board 30 is inserted into the channel 28 and the handle 62 is rotated back to its position of Figure 1, to move the groups of surfaces 54 sequentially back into their board engaging positions. The handle 62 is then pushed rightwardly, i.e. in the opposite direction to that of the arrow B, towards its position of Figure 2 and the free end portion 64 of the handle 62 is resiliently introduced in the recesses 42 so that the contact surfaces 54 are secured in their engagement with the daughter board 30. The daughter board 30 can be subsequently released from the connector by again rotating the handle 62 in the direction indicated by the arrow A, after removing the free end portion 64 of the handle 62 from the recesses 42 and withdrawing the handle 62 in the direction of the arrow B in Figure 1. The groups of contacts 18 are thereby released sequentially so that damage to the circuits to which the contacts 18 are connected and which might arise if the contacts 18 were simultaneously disconnected from the conductors of the board 30, can be avoided.
[0022] There are many cases in which it is either desirable or necessary, or both. for power, ground and signal circuits to be broken sequentially, for mechanical or electrical reasons. For example, where bi-polar logic devices, which have both positive and negative power supplies are employed. the latter being referenced to ground, it may occur if the ground circuit is first broken, that supply voltages will "add" across an individual gate element and so destroy it. In digital electronic systems, for example, the generation, by removal of the daughter board, of spurious transients leading to data falsification can be avoided by arranging for the power circuit to be first broken.
1. A zero insertion force printed circuit board edge connector, comprising an insulating
housing (12) having a channel (28) therein for receiving a printed circuit board (30)
along a board insertion path, a row of electrical contacts (18) positioned on each
side of the channel (28) and extending in a longitudinal direction thereof, each contact
having a contact surface (54) for engaging the printed circuit board (30) when such
has been inserted into the channel (28), and contact-operating means comprising a
cam means (60) movable to displace a contact driving means (16) in the direction in
which the board insertion path extends, to move each contact (18) between a board
receiving first position in which the contact surface (54) of the contact (18) is
withdrawn from the board insertion path and a board engaging second position in which
such contact surface (54) intersects the board insertion path, the contact-operating
means being formed with relatively stepped surfaces (47) succeeding one another in
the longitudinal direction of the channel (28) so that the contacts (18) are moved
sequentially between their first and second positions, in response to the movement
of the cam means (60), characterised in that the relatively stepped surfaces (47)
are provided on the contact driving means (16), these relatively stepped surfaces
serving sequentially to engage the contacts (18) of the rows; and in that the contact
driving means is in the form of a single contact driving member (60) which comprises
a base (44) from opposite edges of which extend side walls (46 and 48), the stepped
surfaces (47) being formed in the free longitudinal edges of the side walls (46 and
48), so that the height of each side wall increases in one longitudinal direction
of the channel (28).
2. A connector according to Claim 1, characterised in that each stepped surface (47)
on the contact driving member (16) is dimensioned to engage a group of the contacts
(18) simultaneously.
3. A connector according to Claim 1 or 2, characterised in that the contact driving
member (16) is positioned between the mouth of the channel (28) and cam member (60)
so as to rest upon the cam member (60) which is rotatable in a groove (40) in the
base of the channel (28) about an axis extending longitudinally of the channel (28)
and is also slidable lengthwise of the groove (40), the cam member (60) having a handle
(62) which extends exteriorly of the housing (12) and is insertable in a recess (42)
therein, to secure the cam member (60) to the housing (12) and to restrain rotation
of the cam member (60) relative to the housing (12), when the contacts (18) are in
their second position.
4. A connector according to Claim 1 or 2, characterised in that the cam member (60)
has a handle (62) which extends exteriorly of the housing (12) and by means of which
the cam member (60) can be rotated relative to the housing (12), the handle (62) having
a free end portion (64) which can be moved relative to the housing (12) to allow the
free end portion (64) of the handle (62) to be lodged in a recess (42) in the housing
(12).
1. Connecteur en bordure pour carts à circuits imprimés à force d'insertion nulle,
comprenant un boîtier isolant (12) qui présente une rainure (28) destinée à recevoir
une carte (30) à circuit imprimé le long d'un trajet d'insertion d'une carte, une
rangée de contacts électriques (18) placée sur chaque côté de la rainure (28) et s'étandant
dans une direction longitudinale de cette dernière, chaque contact présentant une
surface (54) de contact destinée à porter contre la carte (30) à circuit imprimé lorsqu'elle
a été insérée dans la rainure (28), et un dispositif de commande de contacts comprenant
un dispositif à came (60) mobile de manière à déplacer un dispositif (16) d'entrainment
de contacts dans la direction du trajet d'insertion d'une carte, de manière à déplacer
chaque contact (18) entre une première position de réception de la carte dans laquelle
la surface de contact (54) du contact (18) est éloignée du trajet d'insertion d'une
carte et une seconde position d'engagement d'une carte dans laquelle cette surface
de contact (54) coupe le trajet d'insertion d'une carte, le dispositif de commande
de contacts présentant des surfaces relativement épaulées (47) qui se succèdent dans
la direction longitudinale de la rainure (28) de manière que les contacts (18) soient
déplacés séquentiellement entre leurs première et seconde positions en réponse au
mouvement du disositif à came (60), caractérisé en ce que les surfaces relativement
épaulées (47) sont présentées par le dispositif (16) d'entrainment de contacts, ces
surfaces relativement épaulées servant à s'engager séquentiellement contre les contacts
(18) des rangées, et en ce que le dispositif d'entraine- ment des contacts se présente
sous la forme d'un seul élément (60) d'entrainement des contacts, qui comprend un
fond (44) des bords opposés duquel partent des parois latérales (45 et 48), les surfaces
épaulées (47) étant formées dans les bords longitudinaux libres des parois latérales
(46 et 48), de manière que la hauteur de chaque paroi latérale augmente dans une direction
longitudinale de la rainure (28).
2. Connecteur selon la revendication 1, caractérisé en ce que chaque surface épaulée.
(47) de l'élément (16) d'entrainement des contacts est dimensionnée pour s'engager
simultanément contre un groupe des contacts (18).
3. Connecteur selon la revendication 1 ou 2, caractérisé en ce que l'élément (16)
d'entraine- ment des contacts est positionné entre l'entrée de la rainure (28) et
un élément (60) de came de manière à reposer sur l'élément (60) de came qui peut tourner
dans une gorge (40) ménagée dans le fond de la rainure (28) autour d'un axe s'étendant
longitudinalement à la rainure (28) et qui peut ègalement coulisser longitudinalement
à la gorge (40), l'élément (60) de came comportant une poignée (62) qui fait saillie
à l'extérieur du boitier (12) et qui peut être insérée dans un évidement (42) de ce
boitier, afin de fixer l'élément (60) de came au boitier (12) et d'empêcher l'élément
(60) de came de tourner par rapport au boitier (12) lorsque les contacts (18) sont
dans leur seconde position.
4. Connecteur selon la revendication 1 ou 2, caractérisé en ce que l'élément (60)
de came comporte une poignée (62) qui fait saillie à l'extérieur du boitier (12) et
au moyen de laquelle l'élément (60) de came peut être tourné par rapport au boitier
(12), la poignée (62) comportant un tronçon extrême libre (64) qui peut être déplacé
par rapport au boitier (12) afin que le tronçon extrême libre (64) de la poignée (62)
puisse se loger dans un évidement (42) du boitier (12).
1. Ohne Einsetzkraft arbeitender Kantenverbinder für gedrukte Schaltungsplatten, mit
einem isolierenden Gehäuse (12), das einen Kanal (28) zur Aufnahme einer gedruckten
Schaltungsplatte (30) längs einer Platteneinsetzbahn aufweist, mit einer an jeder
Seite des Kanals (28) angeordneten Reihe von elektrischen Kontakten (18), die sich
in einer Längsrichtung des Kanals erstreckt, wobei jeder Kontakt eine Kontaktfläche
(54) zum Eingriff mit der gedruckten Schaltungsplatte (30) aufweist, wenn diese in
den Kanal (28) eingesetzt ist, und mit Kontaktbetätigungsmittein, die ein Nockenglied
(60) aufweisen, das zur Verlagerung eines Kontaktbewegungsmittels (16) in der Richtung,
in der sich die Platteneinsetzbahn erstreckt, beweglich ist, um jeden Kontakt (18)
zwischen einer ersten Plattenaufnahmestellung, in der die Kontaktfläche (54) des Kontakts
(18) aus der Platteneinsetzbahn zurückgezogen ist, und einer zweiten Platteneingriffsstellung
zu bewegen, in der die Kontaktfläche (54) die Platteneinsetzbahn schneidet, wobei
die Kontaktbetätigungsmittel mit relativ zueinander abgestuften Flächen (47) ausgebildet
sind, die einander in der Längsrichtung des Kanals (28) folgen, so daß die Kontakte
(18) de Reihe nach in Abhängigkeit von der Bewegung des Nockengliedes (60) zwischen
ihrer ersten und zweiten Stellung bewegt werden, dadurch qekennzeichnet, daß die relativ
zueinander abgestuften Flächen (47) an dem Kontaktbewegungsmittel (16) vorgesehen
sind, wobei diese relativ zueinander abgestuften Flächen dazu dienen, der Reihe nach
die Kontakte (18) der Reihen zu berühren, und daß das Kontaktbewegungsmittel die Form
eines einzigen Kontaktbewegungsgliedes (16) hat, das einen Unterteil (44) aufweist,
von dessen einander gegenüberliegenden Rändern sich Seitenwände (46 und 48) erstrecken,
wobei die abgestuften Flächen (47) an den freien Längskanten der Seitenwände (46 und
48) gebildet sind, so daß die Höhe jeder Seitenwant in einer Längsrichtung des Kanals
(28) zunimmt.
2. Verbinder nach Anspruch 1, dadurch gekennzeichnet, daß jede abgestufte Fläche (47)
an dem 1-\ontaktbewegungsglied (16) so bemessen ist, daß sie eine Gruppe von Kontakten
(18) gleichzeitig berührt.
3. Verbinder nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß das Kontaktbewegungsglied
(16) zwischen der Mündung des Kanals (28) und dem Nockenglied (60) angeordnet ist,
so daß es auf dem Nockenglied (60) ruht, das in einer Nut (40) im Unterteil des Kanals
(28) um eine Achse drehbar ist, die sich in Längsrichtung des Kanals (28) erstreckt,
und das auch in Längsrichtung der Nut (40) verschiebbar ist, wobei das Nockenglied
(60) einen Handgriff (62) hat, der sich zur Außenseite des Gehäuses (12) erstreckt
und in eine Ausnehmung (42) in diesem einführbar ist, um das Nockenglied (60) an dem
Gehäuse (12) festzulegen und eine Drehung des Nockengliedes (60) in Bezug auf das
Gehäuse (12) zu verhindern, wenn die Kontakte (18) sich in ihrer zweiten Stellung
befinden.
4. Verbinder nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß das Nockenglied (60)
einen Handgriff (62) hat, der sich zur Außenseite des Gehäuses (12) erstreckt und
durch den das Nockenglied (60) in Bezug auf das Gehäuse (12) verdreht werden kann,
wobei der Handgriff (62) einen freien Endteil (64) hat, der in Bezug auf das Gehäuse
(12) bewegt werden kann, um es dem freien Endteil (64) des Handgriffs (62) zu gestatten,
in einer Ausnehmung (42) in dem Gehäuse (12) aufgenommen zu werden.