Note: Descriptions are shown in the official language in which they were submitted.
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01 This invention relates to a connector for releasably
02 connecting a leadless hybrid circuit to a printed circuit board
03 or the like.
04 Hybrid circuits are usually fabricated on a ceramic
05 substrate, on which various conductors and resistors are
06 silk-screened, and to which integrated circuit chips are bonded.
07 Such hybrid circuits are usually interconnected in a system via a
08 printed circuit board, to which they are usually attached either
09 by soldering or via a connector. The hybrid circuit is usually
leadlessr i.e., connections are made to it by soldering jumper
11 wires to bonding pads usually located in rows along its edges, or
12 alternatively, lt is plugged into a socket which contains spring
13 contacts which make electrical contact with connector contacts
1~ disposed along an edge.
It has been found that in a great many instances, the
16 use of plug-in hybrid circuits is more desirable than the use of
17 permanently connected or wired hybrid circuits. In the case of
18 failure or the requirement for servicing, the replacement of only
lg the individual hybrid circuits is considerably less costly than
the replacement of entire printed circuit boards on which a
21 plurality of hybrid circuits may be connected. This replacement
22 is facilitated by plug-in connection, rather than wired
23 connection.
2~1 Connectors for hybrid circuits have previously been
provided which connect along one edge of the hybrid circui-t.
26 There are two types of these connectors, one type which requires
27 insertion orce, in which the terminals of the connector wipe the
28 hybrid circuit mating terminals as the hybrid circuit is
29 inserted, and the zero insertion force type which allows
insertion oE the hybrid circuit into the connector, following
31 which pressure is applied by the mating terminals to make contact
32 and hold the hybrid circuit in position. In the forced entry
33 type of connector, the connector terminals on the hybrid circuit
34 must be thick and robust in order to withstand scraping of the
connector terminals. In both -types of connector, however, the
36 hybrid is disposed at right angles to the printed circuit board.
37 This results in at least two problems, the first be~ng that more
38 terminals are often required, or a highly dense and complex
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01 hybrid circuit, ~han can be accommodated along one edge of the
02 hybrid circuit~ Manual insertion of a second connector at -the
03 end of a flexible cable must be used to obtain connection along
04 the opposite edge of the hybrid circuit. The second problem is
05 that in a system utilizing a large number of printed circuit
06 boards, the width of the hybrid circuit extending outwardly from
07 the plane of the printed circuit board requires that each printed
08 circuit board must be spaced at least the height of the hybrid
09 circuit from the adjacent printed circuit board, thus obviating
dense packing of the printed circuit boards on a rack.
11 The present invention is a hybrid circuit connector
12 which facilitates removable mounting of a hybrid circuit in a
13 plane adjacent and parallel to the plane o~ the printed circuit
14 board. The nature of the connector facilitates automatic
connection to the hybrid circuit along at least two opposite
16 edges, and if desired, along at least major portions of the other
17 two opposite edges. Thus the profile of the printed circuit with
18 components mounted thereon is thin, allowing dense packing of
19 printed circuit boards in a frame. Further, due to the nature of
the connector, virtually the entire E)erimeter of the hybrid
21 circuit can be used to provide connec:tion to the hybrid circuit,
22 obviating the requirement for auxiliary manually applied
23 connectors wired via cables to the pr.inted circuit board for
24 connection to another edge of the hybrid circuit, which would
otherwise be required.
26 The hybrid circuit to be connected to the present
27 connector uses C clips preferably soldered to corresponding
28 connector pad lands on opposite sides of the substrate, to form
29 edge terminals on one side of which at least the hybrid circuit
is connected.
31 It should be noted that since only a short contact
32 length, which i5 comparable to the thickness of the hybrid
33 circuit substrate makes contact with the connector contacts, once
34 the substrate is in position vibration and/or bumping could cause
the substrate to become dislodged. However a lever or paîr of
36 levers are used to insert the hybrid circuit into the connector,
37 and once inserted, to form a lock in order to retain the hybrid
33 circuit reliably in contact position. The levers lock in their
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01 closed positions, and in their open positions provide a pair of
02 jaws which grasp the hybrid circult and move the hybrid circuit
03 into the connector to make contact as the levers are turned
04 toward their closed positions.
05 As a result a connector is provided for retaining the
06 hybrid circuit connected and in parallel relationship with the
07 plane of the printed circuit board with security and reliability,
08 even during transportation during which it would be subject to
09 jarring and vibration. The hybrid circuit can be released from
the connector merely by rotating the levers to their open
11 positions.
12 The invention in general is a hybrid circuit connector
13 comprising a frame for enclosing the periphery of a hybrid
14 circuit substrate, a plurality of resilient contacts disposed
along at least one edge of the frame for making contact with
16 cooperating contacts along an edge of the hybrid circuit
17 substrate, and at least one lever rotatably pinned within one
18 side of the frame for rotation about an axis parallel to the axis
19 of the aforenoted one edge, the lever having a jaw extending
toward the interior of the frame. The jaw has a lower lip for
21 supporting the bottom of the substrate, and an upper lip spaced
22 about the thickness of the substrate above the lower lip or
23 engaging the substrate therebetween, the upper lip having an
24 inner e~tremity toward the interior of the rrame at about the
plane of the inside oE the one side of the frame, when the lever
2~ is at a predefined open position.
27 The jaw or jaws o~ the lever or oppositely disposed
28 levers engage the edge or opposi~e edges of the hybrid substrate
29 respectively as the levers are rotated from an open to a closed
position, forcing the substrate into the connector~ which engages
31 ~he connector contacts by sliding contact with the coopPrating
32 contacts of the hybrid circuit. Once the levers are in their
33 closed positions, interfering protrusions and cooperating concave
34 depressions in the lever and frame sides retain the levers in
position, thus holding the substrate in position in spite of
36 vibration, bouncing, etc.
37 Rotation of the lever or levers to their open position
38 forces the substrate out of the connector and out of contact
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01 engagement.
02 The lnven-tion more generally is a hybrid circuit
03 connector comprising a frame having a plurality of resilient
04 contacts disposed along at least one inner side -for making
05 contact with cooperating contacts disposed along an edge of the
06 hybrid circuit substrate, apparatus for forcing the hybrid
07 circuit substrate into the frame whereby the contacts along the
08 edge of the hybrid circuit make contact with said resilient
09 contacts, and apparatus for locking the substrate in its position
within the frame.
11 A better understanding of the invention will be
12 obtained with reference to the detailed description below, with
13 reference to the following drawings:
14 Figure 1 is a partial section of a prior art form of
hybrid substrate connector,
16 Figure 2 is a section of the present invention along
17 one axis,
18 Figures 3, 4 and 5 are a partial section, a partial
19 section and a full section respectively of the present invention
along an axis orthogonal to that of Figure 2, showing the lever
21 in fully opened, partially opened, and fully closed positions,
22 Figure 6 is a detail, oE the lever in opened position,
23 Figure 7 is a detail of the lever in closed position,
24 and
Figure 8 is a perspective of the invention.
26 Turning to Figure 1, an edge view of a prior art hybrid
27 connector is shown. A hybrid substrate 1 having silk-screened
28 resistors, conductors, etc., and bonded integrated circuits on
29 one side ~not shown) has a series of conrlector pads 2 adherent on
at least one side. The hybrid substrate is inserted into a
31 connector 3 which is fixed to printed circuit board 4. The
32 connector includes a plurality of resilient contacts 5 which make
33 electrical connection with the substrate contact pads 2. It may
34 be seen that the hybrid substrate extends orthogonally to the
plane of the printed circuit board 4. Consequently an adjacent
36 printed circuit board mounted in a rack cannot be located closer
37 than at least the width of the hybrid substrate, plus its
38 connector facility, plus some air gap for tolerance.
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01 Some hybrid substrates have a second row of contact
02 pads 2A disposed on its surface, to which a second connector 3A
03 can be connected, in order to increase the number of contact
04 points made available on the hybrid substrate for connection to
05 the circuit carried thereon. The connector 3A is connected to
06 the printed circuit board conductors via a bundle of wires 6
07 which must soldered both to the connector 3A and the printed
08 circuit board 4. While wiring of the printed circuit board is
09 often performed using automated techniques, the use of wires 6
and connector 3A oEten requires manual interference in the
11 process, and the re~uirement for slack in wire 6 results in its
12 movement during the transportation of the system, and can cause
13 breakage of the wires.
1~ Figure 2 is a sectional view along A-A of Figure 8
illustrating the present invention, but with a hybrid substrate
16 10 held within a preferably rectangular connector 11. The basic
17 orm of the connector is similar to a picture frame for enclosing
18 the hybrid substrate within the frame.
19 A plurality of resilient contacts 12 are held inwardly
of preferably a pair of opposite inner sides of the connector,
21 for contacting corresponding contacts of the hybrid substrate 10
22 disposed along opposite edges thereof. The contacts are fixed to
23 the frame using conventional techniques.
24 Also shown in Figure 2 is a lever 13 which rotates
about an axis extending between the sides of the connector frame
26 to which the contacts 12 are fixed.
27 Bonded for electrical contact to the circuit carried by
28 the substrate 10 are a plurality of C clips 14, which extend from
29 bonding pads 15 around the edges of the substrate to oppositely
disposed bonding pads on the other side thereof. The C clips are
31 preferably soldered to the bonding pads, but the solder should be
32 restricted from wicking along the C clips at the edges of the
33 substrate in order not to interfere with their contacting
34 connector contacts 12.
While the shape of the C clips around the edges of the
~36 substrate can be slightly rounded to facilitate smooth engagement
37 with the connector contacts 12, it is preferred that they should
38 be flat along the edges of the substrate or cooperatively shaped
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01 with the connector contacts in order to make maximum surface
02 contact therewith.
03 A prototype system used C clips for contacts on the
04 hybrid substrate fabricated of phosphor bronze~ coated with tin
05 lead solder plate.
06 Figures 3, 4 and S show partial and full sectional
07 views through the invention along section YY of Figure 2, at
08 right angles to the section shown in Figure 2, illustrating
09 operation of the lever inserting the hybrid substrate into
position within the connector. A lever 16 is rotatably pinned by
11 means of pin 17 to a channel in the side of the connector.
12 (Preferably two similar levers are used at opposite sides of the
]3 frame,) In Figure 3 the lever 16 is shown in open position. It
1~ should be noted that a seat 18 of the lever has a portion which
is parallel to the surface of the printed circuit board 4 and
16 rests thereon when in fully open position. In this position a
17 jaw in the lever has a lower lip 19 which is approximately level
18 with the top o~ the frame and extends inwardly of the frame,
19 upon which the substrate 10 rests prior to insertion into the
connector. An upper lip 20 extends inwardly of the frame only
21 to the inner edge of the frame of the substrate, in order to
22 allow the edge of substrate 10 to pass without interference as it
23 is placed on lower lip 19.
24 In Figure 4, lever 16 has been rotated toward its
closed position. The upper lip 20 makes contact with the upper
26 surface of hybrid substrate 10 as lever 16 rotates about pin 17.
27 At the same time the edge of substrate 10 is enveloped within the
28 jaw of lever 16.
29 In Figure 5 two opposite levers 16 are shown in their
closed positions. The substrate 10 is now in the same position
31 as that shown in Figure 2, Figure 5 being a section at 90
32 thereto, however. Conse~uently connector contacts are not shown
33 along the left and right side edges of substrate 10 in Figure 5.
34 ~owever it should be noted that contacts could have been utilized
on either or both sides of the levers. The substrate is seated
36 in position at which its contacts make contact with the resilient
37 connector contacts, the bottom of the substrate resting on the
38 lower lips of levers 16 and a lower ridge 21 stretching across
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01 the connector on both sides thereof having an upper surface at
02 the same height as the lower lip and positioned to support the
03 substrate along i-ts opposite sides.
04 If additional connector contacts are to be used along
05 the sides incorporating the levers, rather than ridges 21, posts
06 or other supports could be used.
07 In order to release the substrate, levers 16 are
08 rotated to their open position, the lower lips 19 pushing the
09 bottom of the substrate upwardly, thus releasing the substrate
which had been spring wedged by the connector contacts within the
11 connector.
12 It should be noted that for the use of only a single
13 lever, an appropriate slot should be formed along one inner side
14 of the connector frame to accommodate and hold an edge of the
substrate. The single lever is then used to insert the other
16 side and lock the substrate into position. It is noted however
17 that the two lever embodiment is preferred, in order to avoid
18 lateral movement as between adjacent connector and hybrid circuit
19 contacts which would occur when inserting the hybrid substrate
initially into the slot.
21 The levers are locked into their closed positions in
22 order to retain the substrate reliably in contact with the
23 connector contacts in the presence of vibration, etc. According
24 to the preferred Eorm oE the lock, each lever has a protrusion or
bump 22 on both sides thereof, which has sufficient width so as
26 to interfere with the adjacent edge of the connector side as the
27 levers rotate from open to closed positions.
28 Referring to Figures 6 and 7 which show details
29 thereof, lever 16 in Figure 6 is open and in Figure 7 is closed.
The adjacent edges of the sides o~ the connector contain slots
31 immediately adjacent the levers into which the protrusions
32 cooperatively fit, located opposite the protrusions or bumps when
33 the levers are in closed positions. Consequently as each lever
34 1~ is rotated from its open position toward its closed position,
it first encounters interference between the adjacent edges of
36 the corresponding side to which it is pinned. ~nce it reaches
37 its closed position, the protrusion 22 fits into slot 23, which
3B substantially retains the lever in position. It has been found
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01 that vibration of the substrate 10 against lever 16 is
02 insufficient to overcome the mechanical advantage resulting from
03 the position of lever 16~ and thus lever 16 retains the substrate
04 in position. In a prototype, Eor example, shock of 30g in any of
05 the three mutually perpendicular planes or by vibration thereof
06 at .5g from 5 to 100 hertz and 1.5g from 100 to 50n hertz did not
07 dislodge the substrate.
08 It is preferred that one corner of each substrate
09 should be chamfered, and a corresponding key should be used
across the corner of the connector to facilitate matching and
11 orientation of the hybrid substrate during insertion.
12 In operation, the levers 16 are opened to the their
13 maximum position at which time their seats 18 rest against the
14 printed circuit board to which the connector is connected. The
hybrid circuit is properly oriented, placed flat against the
16 connector and is supported by the lower lips of the levers. The
17 levers are then rotated toward their closed position, which
18 thereby force the hybrid circuit into engagement with the
19 connector. The levers are retained in that position, effectively
locking the substrate into position by means of protrusions 22
21 engaged in slot 23.
22 A person understanding this invention may now conceive
23 of variations in design and other embodiments utilizing the
24 principles described herein. All are considered to be within the
~25 sphere and scope of the invention as defined in the claims
26 appended hereto.
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