[0001] The present invention relates to an electrical connector for printed circuit boards
and more particularly to a high speed coaxial connector for electrically connecting
two circuit boards together.
[0002] Current technology utilizes removably connected printed circuit boards. A daughter
board is removably connected to a mother board allowing the daughter board to be replaced
as needed. Terminals of the connector electrically connect contact areas of the daughter
board to contact areas of the mother board. This requires connectors with multiple
rows of closely spaced terminals (0.100 inch centerlines or less) therein. The connectors
employ stamped and formed terminals which are inserted into plastic, metal or metallized
housings using dielectric sleeves which are molded onto the terminals.
[0003] In current electronic circuits, the use of increasingly higher speed switching signals
has necessitated control of impedance for signal transmission. At the connector interfaces
between mother boards and daughter boards this has been accomplished primarily by
alternating ground terminals with signal terminals in the connectors in order to provide
a signal reference path and shielding for the signal path. Traditionally, large numbers
of terminals are used for ground, with as many as eight terminals being used as ground
for every one that is used for signal. Thus in the prior art, the number of terminals
used for signal transmission is drastically limited, which in turn limits the amount
of contact areas which can be beneficially connected between the mother board and
the daughter board for signal connection purposes.
[0004] In an attempt to provide a connector which allows all terminals to be used for signal
transmission, a coaxial type connector described in U.S. Patent Number 4,451,107 was
devised. Although some of the above mentioned problems where solved, other serious
problems arose. At high speed transmission the right angle of the terminals caused
reflection of the signals, limiting the effectiveness of the connector at high speed
transmission. Also limiting the effectiveness of the connector is the fact that the
molded dielectric constant of the material of the housing cannot by itself be low
enough for high speed transmission in the high gigahertz range.
[0005] Other problems include insertion and manufacturing difficulties. As the number of
terminals required increases, the insertion force of the male connector into the female
connector becomes impractical. In other words, the insertion force becomes so great
that the mating halves of the connector cannot be mated together, or the housing and
contacts are damages as insertion occurs. The manufacturing of the connector described
in U.S. Patent Number 4,451,107 is also made impractical by the manufacturing process
of die casting the metal housing, injection molding a nylon sleeve, and casting the
terminals through the nylon sleeves in the housing. This process of manufacturing
is very difficult to control and can lead to faulty connections. Therefore, the configuration
of the invention of the above cited reference is impractical for many reasons.
[0006] A multi-pin coax connector assembly having connectors made of metal or conductive
plastic is described. The conductive material serving as a reference ground for all
signals. Pin and socket terminals, placed in respective connectors are insert molded
with insulating material. The insulating material provides the space required between
the connector housing and the terminals. The configuration of the insulating material
provides for air gaps along most of the length of the terminals, allowing the effective
dielectric constant to be lower than any plastic enabling the required controlled
impedance of the signal pathway and required speed of the signal to be attained. The
connectors are provided with power and ground busses, as well as a camming means.
The camming means allows the connectors to be mated under low insertion force conditions.
As the connectors are mated together the power and ground busses engage and make electrical
engagement with the respective power and ground busses of the mating connector. Once
the connectors are mated, the camming means is engaged, forcing the pins and sockets
to be completely mated thereby providing a positive wiping action and ensure that
a positive electrical connection is effected for all signal pins after the ground
and power are connected.
[0007] The present invention is directed to an electrical connector assembly having a first
electrically conductive connector with housing means. The housing means has at least
one row of terminal receiving passages extending from a first surface to a second
surface, the terminal receiving passages having an angle therein. First terminals
are located in the passages, the terminals having essentially the same configuration
as the terminal receiving passages. Dielectric material coaxially surrounds the terminals
in designated areas, insulating the terminals from the housing means and providing
the spacing required to properly position the terminals in the terminal receiving
passages.
[0008] A second electrically conductive connector is also provided, the connector having
housing means which have at least one row of terminal receiving passages extending
therethrough. The passages of the first connector and the second connector are in
alignment. Second terminals are located in the terminal receiving passages, mating
ends of the second terminals cooperate with mating ends of the first terminals. The
second terminals have dielectric coaxially surrounding the terminals in designated
areas of the terminal receiving passages. The dielectric insulates the terminals from
the housing means and provides the spacing required to properly position the terminals
in the passages.
[0009] A further object of the present invention is to provide a connector assembly which
has reduced insertion force, while still providing a positive wiping action between
the first and the second terminals.
[0010] A further object of the present invention is to provide a connector assembly which
allows for high speed transmission of signals while minimizing reflections and discontinuities
which distort the signals.
[0011] A further object of the present invention is to provide engagement and connection
for power and ground terminals prior to engagement and connection of signal terminals
or pins.
[0012] The invention will now be described by way of example with reference to the accompanying
drawings, in which:
FIGURE 1 is a perspective view of a connector assembly showing a plug connector exploded
from a receptacle connector.
FIGURE 2 is an exploded perspective view of the plug connector.
FIGURE 3 is an exploded perspective view of the receptacle connector.
FIGURE 4 is a cross-sectional view of the connector assembly when the plug connector
is fully inserted into the receptacle connector.
FIGURE 5 is a partially exploded cross-sectional view of the plug connector.
FIGURE 6A is a diagrammatic view of a pin just prior to insertion into a terminal.
FIGURE 6B is a view similar to that shown in Figure 6A, showing the pin inserted into
the terminal.
FIGURE 7 is a partially exploded cross-sectional view of the receptacle connector.
FIGURE 8 is a partial elevational view of a camming member.
FIGURE 9 is an end elevational view of the camming member and assembly.
FIGURE 10 is a fragmentary view showing an alternative embodiment of the camming rod.
[0013] A low insertion force (LIF) coaxial connector assembly 2 for electrically connecting
a mother board 4 to a daughter board 6 is comprised of an electrical plug connector
8 and an electrical receptacle connector 10 which mate together to form connector
assembly 2. Each connector 8, 10 has a plurality of terminal receiving passages 12,
14, 16 extending therethrough, each of which is profiled to receive a respective terminal
18, 20 therein. Terminals 18, 20 are insulated from the conductive housings of the
connectors by an appropriate dielectric material.
[0014] Connectors 8, 10 have housings 22, 24, 26 which are molded from metal or metallized
plastic having the appropriate conductive characteristics. Metal plating may be performed
on a molded plastic housing to provide these required conductive characteristics.
[0015] Plug connector 8, as shown in Figures 2, 4 and 5 is comprised of mating conductive
housing 22 and terminal support conductive housing 24. Rear surface 28 of mating housing
22 abuts front surface 30 of terminal support housing 24 when plug connector 8 is
fully assembled.
[0016] Rear surface 28 of mating housing 22 has embossments 27 provided thereon. The embossments,
as best shown in Figure 3, are provided in parallel rows which extend between passages
12. Recesses 29 are provided in the front surface of terminal support conductive housing
24. The configuration of the recesses 29 corresponds to the configuration of the embossments
27. Consequently, as mating housing 22 and terminal support housing 24 are joined
together, the embossments 27 cooperate with the recesses 29 to provide an interference
fit therebetween.
[0017] In this assembled position a plurality of passages 12, 14 extends through connector
8 from front surface 32 of housing 22 to rear surface 34 of housing 24. Passages 12,
14 are arranged in three parallel rows, with the first row being adjacent side surface
36 of housing 22 and side surface 38 of housing 24, the third row being adjacent surface
40 of housing 22, and the second row being between the first and third rows. It should
be noted that although three parallel rows are shown and described, any possible configuration
of rows is possible.
[0018] As shown in Figures 4 and 5, each housing 22, 24 has passages 12, 14 which cooperate
to form the continuous passages when housings 22, 24 are joined together. However,
as passages 14 of support housing 24 are positioned at an angle relative to front
surface 30, an angle or bend 42 is necessarily provided in the continuous passages
when housings 22, 24 are joined together. Bend 42 shown in Figure 4 is essentially
one hundred thirty-five degrees, but the actual angle can range between one hundred
and one hundred seventy degrees, as will be more fully explained below. It should
be noted that bend 42 may also be arcuate in shape.
[0019] Passages 14 of support housing 24 have uniform cross sections throughout the length
of passages 14. However, passages 12 of mating housing 22 have varied non-uniform
cross sections. Wide portions 44 of passages 12 are proximate front surface 32 of
housing 22 and have a larger diameters than narrow portions 46 of passages 12 which
are proximate rear surface 28 of housing 22. This shape of passages 12 enables terminals
18 to be properly secured therein, as will be discussed.
[0020] Stamped and formed terminals 18 with dielectric member 48 molded onto terminals 18
are positioned in passages 12. The configuration of dielectric member 48 varies according
to the characteristics desired. In the embodiment shown, dielectric member 48 is molded
in cylindrical shapes proximate forked ends 50 of terminals 18. Each cylindrical dielectric
member 48 has projections 52, 54 extending from either end to secure terminals 18
in passages 14, as well as to provide the spacing required to prevent terminals 18
from engaging housing 22. A dielectric member 56 of spiral configuration is provided
proximate cylindrical dielectric member 48. Each spiral dielectric member 56 resembles
that of a coil spring which has been slightly stretched, leaving air spaces between
the coils, as will be discussed. It should be noted that passages 12, closest to surface
40 are not long enough to support spiral dielectric member 56, therefore cylindrical
dielectric member 49 are provided.
[0021] The combination of spiral dielectric members 56 with cylindrical dielectric members
48, 49, as shown in Figures 2, 4 and 5, not only accurately positions terminals 18
in passages 12 but also provides for air gaps 58 over most of the length of terminals
18. This allows the effective dielectric constant of each passage 12 to approach 1.1,
whereas the plastic dielectric constant is substantially higher, for example 3.2.
The effective dielectric constant of 1.1 permits the controlled impedance to be approximately
50 ohms with 5 amps per contact and 68 ohms with 3 amps per contact where terminals
are positioned on a .100˝ grid. These numbers are merely an example and are not meant
to limit the scope of the invention.
[0022] Each terminal 18 has forked end 50 which is positioned proximate front face 32 of
housing 22. Forked end 50 is twisted relative to the rest of terminal 18, allowing
forked end 50 to cooperate with a respective pin terminal 20 of receptacle connector
10, as will be discussed. As shown in Figures 6A and 6B, each forked end 50 has arcuate
surfaces 60 which act as a lead in when pin terminal 20 and forked end 50 are mated
together, thereby eliminating the need for pin 20 and forked end 50 to be perfectly
aligned when mating occurs.
[0023] Extending from forked ends 50 are dielectric engagement portions 62 which have the
dielectric inserts molded thereon, as was previously discussed. Portions 62 are of
varying lengths, the length depending on passages 12 in which the respective terminals
18 are disposed. Bends 64 are provided in portions 62. Bends 64 correspond to the
bends of the continuous passages. The angle of bends 64 is such that reflection of
the high speed signals in minimized. Daughter board contact ends 66 are positioned
at the end of portions 62 opposite forked ends 50. Ends 66 can be either short, arcuate
projections as shown in Figure 4, or long, straight posts. These alternative mounting
means allow for terminals 18 to be respectively surface mounted to board 6 or on plated
through holes via compliant section 66a of the type disclosed in U.S. Patent No. 4,186,982.
Whichever shape, ends 66 extend from rear surface 22 of support housing 24 to make
electrical engagement with daughter board 6.
[0024] Terminals 18 with dielectric members 48, 56 molded thereto are inserted into passages
12 through front surface 32 of housing 22. As insertion occurs, projections 52 engage
walls of narrow portions 46 of passages 12, causing an interference fit therebetween.
Insertion continues until surfaces 68 of projections 54 of dielectric members 48 engage
shoulders 12a of passages 12 which are the transitions between wide portions 44 and
narrow portions 46 of passages 12. It should be noted that as this occurs projections
54 also provide an interference fit with respective walls of wide portions 44 of passages
12. Therefore, terminals 18 are maintained in passages 12 by the interference fit
of projections 52, 54 of dielectric member 48 in engagement with walls of passages
12. The portions of terminals 18 extending from rear surface 28 of mating housing
22 are then bent at an appropriate angle as shown in Figures 4 and 5. Support housing
24 is inserted over the exposed portions of terminals 18 until front surface 30 of
support housing 24 engages rear surface 28 of mating housing 22. To ensure that support
housing 24 is not improperly inserted over terminals 18, projection 70 of housing
22 is engaged by housing 24 to ensure that these housings are properly positioned
relative to one another.
[0025] After housing 24 is positioned onto housing 22, terminals 18 extend beyond rear surface
34 of support housing 24. The remaining exposed portions of terminals 18 is then bent
according to the use of assembly 2. Either terminals 18 are cut and bent into arcuate
projections of the type required for surface mounting or terminals 18 are bent as
needed, enabling the exposed posts to be used in cooperation with a circuit board
that requires plated through hole mounting to ensure electrical engagement. Projections
72 extend from rear surface 34 of housing 24 to cooperate with daughter board 6 when
connector 8 is positioned on board 6, maintaining the spacing required between connector
8 and board 6. Daughter board 6 is maintained in contact with connector 2 by screws
or the like which extend through holes in mounting members 74 of support housing 24
to cooperate with respective holes of board 6. Mounting members 74 have projections
75, and slots 77 which cooperate with projections 79, 81 on respective housings 24,
22 to secure housings 22, 24 together, as well as secure housings 22, 24 to members
74.
[0026] Receptacle connector 10 includes conductive housing 26 having a front surface 76
and a rear surface 78. Passages 16 extend through housing 26 from front surface 76
to rear surface 78. Passages 16 are arranged in three parallel rows, with the first
row being adjacent sidewall 80, the third row being adjacent sidewall 82, and the
second row being between the first and third rows. The rows of passages 16 of receptacle
connector 10 align with the rows of passages 12 of mating housing 22 of plug connector
8 enabling the connectors to be electrically mated together. It should be noted that
although three parallel rows are shown and described, any possible configuration of
rows is possible, as long as rows of receptacle connector 10 align with rows of plug
connector 8.
[0027] Passages 16 of housing 26 have non-uniform cross sections as shown in Figure 7. Portions
84 of passages 16, adjacent rear surface 78, have a larger diameter than portions
85 which extend front surface 76. This non-uniform shape of passages 16 enables terminals
20 to be properly secured therein, as will be discussed.
[0028] Stamped and formed pin terminals 20, shown in Figures 3-5, are positioned in passages
16. Terminals 20 are essentially straight and have a narrow end 88 at one end thereof.
Dielectric member 90 is insert molded over the terminals such that the configuration
of dielectric member 90 varies according to the characteristics desired. In the embodiment
shown in Figures 3-5, dielectric member 90 is molded in a cylindrical shape having
projections 92, 94 extending from ends thereof to secure terminals 20 in passages
16, as well as to provide the spacing required, ensuring that terminals 20 are positioned
a proper distance away from the wall of passages 16, permitting controlled impedance.
[0029] Narrow ends 88 of terminals 20 extend from housing 26, past front surface 76 into
a cavity 95 formed by the walls 80, 82 of housing 26. Extending from ends 88 are dielectric
engagement portions 96 which have dielectric members 90 insert molded thereon. Mother
board contact ends 98 are positioned at the end of portions 96 opposite ends 88. Ends
98 extend from rear surface 78 of housing 26 to make electrical engagement with mother
board 4. Figure 3 shows connector 10 having terminals 20 with posts including compliant
sections for electrical connection with plated through holes of mother board 4, however,
connector 10 can have terminals 20 which have arcuate ends suited for electrical engagement
with contact pads of mother board 4, i.e. surface mounting.
[0030] Terminals 20 with dielectric members 90 molded thereto are inserted into passages
16 of receptacle connector 10 through rear surface 78. As insertion occurs, projections
92 cooperate with the walls of narrow portions 85 to provide an interference fit.
Insertion continues until surfaces 99 of projections 94 engage shoulders 86 between
narrow portions 86 and wide portions 84 of passages 16, thus defining a stop position.
Projections 94 also provide an interference fit with the walls of wide portions 84
of passages 16. Therefore, terminals 20 are maintained in this position by the interference
fit of projections 92, 94 in cooperation with the walls of passages 16 of connector
10. Mother board 4 acts as a secondary securing means for terminals 20. As connector
10 is brought into contact with board 4, the dielectric members 90 engage board 4,
causing mother board 4 to act as a securing means, maintaining terminals 20 in connector
10. Mother board 4 is secured to connector 10 by screws or the like which cooperate
with holes in mounting members 97 of housing 26 of connector 10 and respective holes
of mother board 4. Mounting members 97 have projections 89 which cooperate with cavity
95 to maintain connector 10 to board 4 when the screws are secured in place. The screws
have positioning posts 93 extending upward therefrom, posts 93 cooperating with openings
91 in members 74 to align connector 8 with connector 10.
[0031] It should be noted that mounting members 74 and 97 have recesses and projections
which cooperate with the ends of connectors 8 and 10 respectively to secure members
74, 97 to connectors 8, 10. If a longer connector assembly is desired a special end
block is provided which enables connector assemblies to be connected together in one
long connector. The special end blocks actually being intermediate blocks which allow
connection of the connector while providing periodic securing means.
[0032] It is important to realize that all the various metallized plastic housings must
be in electrical engagement with each other in order for a continuous electrical ground
path to be provided. As was previously discussed, embossments 27 and recesses 29 are
provided to insure that a positive electrical ground connection is provided between
housings 22 and 24. However, this same solution cannot be used between circuit board
4 and housing 26, between housing 26 and housing 22, and between housing 24 and circuit
board 6. Consequently, a different solution must be employed. In order to provide
the electrical connection required, interconnections members 160,162,164 are provided
between circuit board 4 and housing 26, between housing 26 and housing 22, and between
housing 24 and circuit board 6.
[0033] Interconnection members 160,162,164, as best shown in Figures 2, 3 and 4, are essentially
identical. For ease of description, only interconnection member 162 will be discussed
in detail. The reference numbers used will be used on the other interconnection members
160,164, as the parts are identical.
[0034] Interconnection member 162 is stamped and formed from any material having the desired
conductive characteristics. Member 162 has a first major surface 166 and a second
major surface 168. Openings 170 extend from first major surface 166 through second
major surface 168. The pattern in which openings 170 are arranged corresponds to the
pattern of the terminals. Cantilever spring arms 172, 174 are provided proximate openings
170. Cantilever spring arms 172, 174 are positioned in parallel rows, the pattern
of spring arms 172, 174 is essentially identical to the pattern of embossments 27
provided on housing 22. Spring arms 172 extend beyond first major surface 166 and
spring arms 174 extend beyond second major surface 168. Consequently, as the various
housings and circuit boards are mated together, interconnection members 160, 162,
164 will cooperate with the mating surfaces to provide the electrical connection required.
This is insured because spring arms 172, 174 will engage respective surfaces as mating
occurs. In fact, spring arms 172, 174 will create a slight wiping action to insure
that a positive electrical connection is made. Therefore, as all the housings and
circuit boards are in electrical engagement, a uniform electrical ground path is provided
around each terminal insuring that the proper signal reference path and shielding
is present.
[0035] As shown in Figures 5 and 7, power busses 100, 102 and ground busses 104, 106 are
provided on connectors 8, 10. The general shape of busses 100, 102, 104, 106 of connectors
8, 10 are essentially the same as the shape of the outside surfaces of the respective
connectors 8, 10 with which the busses cooperate. Power busses 100, 102 have a layer
of dielectric material provided thereon, to prevent the power from travelling from
the busses to the metallized housing. Each bus has pins 101 extending from the end
of the bus which is adjacent the respective circuit board. Pins 101 are provided on
0.100 inch centerlines, such that upon placement of the busses on appropriate circuit
boards, pins 101 may be removed according to need. Accordingly, only pins 101 which
correspond to appropriate areas of engagement with the circuit board are retained,
the rest are removed.
[0036] Power and ground busses 100, 104 of plug connector 8, Figure 5, are inserted into
channels 108 of mating housing 22 and retained therein by an interference fit. Busses
100, 104 are provided to span the entire length of connector 8. The shape of the ends
of busses 100, 104 which cooperate with board 6 can be either arcuate or straight
to correspond to the shape of the ends of terminals 18 which allows for surface mounting
or through hole mounting respectively.
[0037] Power and ground busses 102, 106 of receptacle connector 10, Figure 7, are inserted
into respective passages 110 of housing 26 of connector 10. Projections 112 of passages
110 cooperate with busses 102, 106 to provide an interference fit to maintain busses
102, 106 in position. As can be seen from Figure 7, ground bus 106 and power bus 102
have similar configurations. Arcuate sections 114 are provided periodically at an
end of each bus 102, 106, such that sections 114 cooperate with the walls of housing
26 to prevent movement of busses 102, 106 relative to connector 10, as shown in Figures
1 and 7. The ends of busses 102, 106 may be either arcuate or straight to correspond
to the shape of the ends of terminals 20 and to allow for either surface mounting
or through hole mounting.
[0038] Projections 116 are present on busses 102, 106 of connector 10 such that projections
116 electrically and wipingly engage busses 100, 104 of connector 8 when connectors
8, 10 are mated together. This ensures that that as connectors 8, 10 are mated together,
power and ground busses 100, 104 make electrical contact with the respective power
and ground busses 102, 106 of the mating connector. Consequently, a power and a ground
bus is supplied between mother board 4 and daughter board 6, providing the required
power supply necessary to ensure that daughter board 6 functions properly, as well
as providing a shielding to shield the connector assembly 2 from outside interference.
[0039] Connector assemblies 2 are designed such that the number of terminals which can be
used in a small space is maximized. This important feature causes problems when the
connectors are to be mated together. The force required for proper insertion is too
great and, therefore, improper insertion or failure of the connectors is a likely
occurrence. Consequently, a zero or low insertion connector assembly is essential
for effective operation.
[0040] One form of zero or low insertion force connector requires the use of a camming assembly.
Figures 8 and 9 show one type of camming assembly 118 which can be used in conjunction
with connector assembly 2. Camming assembly 118 extends the entire length of connector
assembly 2. Mounting projections 120 extend from ends 129, 130 of member 119 such
that openings 122, provided in mounting projections 120, are configured to accept
bolts 124 which align with corresponding holes of board 4. The use of bolts 124 allows
camming assembly 118 to be secured to board 4.
[0041] Referring to Figure 8, opening 126 extends through member 119 from end 129 to end
130. Camming rods 134a, 134b are movably positioned in opening 126. Recesses 128 are
provided in member 119 adjacent ends 129, 130 and extend from top surface 131 in communication
with opening 126. Recesses 128 are provided to accept rods 132 which extend from connector
8 of connector assembly 2 through board 6 (as shown in Figure 9). Recesses 136 of
rods 134a, 134b align with recesses 128 such that rods 132 are disposed in recesses
136, as shown in Figure 8. As rods 134a, 134b are moved, recesses 136 cause rods 132
to move within recesses 128. This movement forces connector 8 to move in a direction
which is parallel to the plane of board 4. Consequently, connector 8 moves relative
to connector 10, forcing terminals 18 into electrical engagement with terminals 20
as will be explained.
[0042] Terminals 20 of receptacle connector 10 are inserted to the side of terminals 18
of plug connector 8 as connectors 8, 10 are mated together, as shown in Figure 6.
In other words as connectors 8, 10 are mated together terminals 18 and terminals 20
do not contact or barely contact each other. This allows connectors 8, 10 to be mated
together under low insertion force conditions and also provides the important feature
of assuring that power busses 100, 104 and ground buss 102, 106 are in electrical
engagement before signal terminals 18, 20 are placed in electrical engagement with
each other. Once connectors 8, 10 have been brought into engagement, camming assembly
118 is operated, causing plug connector 8 to move relative to receptacle connector
10. Consequently, pins 20 are forced into engagement with lead in arcuate surfaces
60 of forked ends 50 of terminals 18, shown in Figure 6a. As this camming motion occurs,
terminals 20 contact the sides of forked ends 50, thereby providing a wiping action
to ensure that a positive electrical connection is effected. In the fully cammed position,
Figure 6b, terminals 20 are fully inserted into forked ends 50, thereby maintaining
a positive electrical connection.
[0043] The movement of rods 134a, 134b is caused by the movement of action lever 138, as
shown in Figures 8 and 9. Action lever 138 is connected to activation rod 140 which
is in turn connected to a camming wheel 142. Wheel 142 is connected to rods 134 by
pins 144 disposed in arcuate camming slots 146 of wheel 142, as shown in Figure 8.
Consequently, as lever 138 is turned in the direction of the arrow in Figure 8, rod
140 is rotated causing wheel 142 to rotate which in turn causes pins 144 to move in
camming slots 146. The configuration of camming slots 146 cause rod 134a to move outwardly,
away from wheel 142, while rod 134b is moved inwardly, toward wheel 142. The movement
of rods 134a, 134b cause rods 132 to move in the same direction, which in turn causes
connector 8 to move as previously described. Consequently, as lever 138 is turned,
terminals 18 are moved into electrical engagement with terminals 20.
[0044] Wheel 20 is positioned in opening 148 of member 119 which extends through camming
assembly 118 from side 150 to side 152 (Figure 9). To hold wheel 142 in place rods
134a and 134b have slots positioned at the ends thereof which cooperate with opening
148. Wheel 142 is positioned in the slots and pins 144 are inserted through openings
154 provided in rods 134a and 134b, thereby securing wheel to rods 134a, 134b. ln
order to change wheel 142 and camming rods 134a, 134b, pins 144 are removed allowing
the wheel and the camming rods to be replaced as required.
[0045] Another configuration of camming assembly 118 has camming rods 135 which have a sloping
surface 137, as shown in Figure 10. Recesses 139 are narrower and longer than the
recesses 128 previously described. Arcuate camming slots 146 are also configured in
a slightly different manner, such that as wheel 142 is turned, rods 135 are moved
outward, away from wheel 142. Consequently, as rods 135 are moved outward, away from
wheel 142. Consequently, as rods 135 are moved, surfaces 137 cooperate with rods 132,
forcing them downward. As rods 132 are attached to connector 8, the downward motion
of rods 132 forces connector 8 to move downward relative to connector 10. This downward
motion causes terminals 18 to be electrically connected to terminals 20, thereby providing
a positive locking action between terminals 18 of connector 8 and terminals 20 of
connector 10.
[0046] Camming assembly 118 also acts as a stiffening member. Board 4 is subject to warpage
and bending, which causes the string of connected assemblies 2 to bend accordingly,
causing an unreliable electrical connection to occur between terminals 18 and terminals
20. Consequently a stiffening member can be useful. Camming assembly 118, is manufactured
from a metal and other material having the required characteristics and is secured
to board 4 by bolts 124 and therefore, provides the stiffening required to insure
that the board is only subjected to minimal bending, which in turn insures that a
reliable electrical connection is effected between the terminals.
[0047] It must be noted that although camming assembly 118 is shown in detail, other types
of camming assemblies will perform equally as well. The camming assembly must move
the terminals into electrical engagement, ensuring that a positive electrical connection
is effected and maintained.
1. An electrical connector (22,24) comprising a first and a second electrically conductive
housing (22,24), the first electrically conductive housing (22) having at least one
row of first passages (12) therein, each first passage (12) extending from a first
surface (32) to a second surface (28) of the first housing (22), the second electrically
conductive housing (24) having at least one row of second passages (14) therein, each
second passage (14) extending from a first surface (30) to a second surface (34) of
the second housing (24), each second passage (14) is at an angle relative to the first
and the second surface (30,34) of the second housing (14), such that as the first
and second housings (22,24) are brought together the passages (12,14) of the respective
housings (22,24) align to form terminal receiving passages (12,14) which extend through
the connector (22,24), the terminal receiving passages (12,14) having a bend at the
juncture of the housings (22,24), terminals (18) positioned in the passages (12,14),
each terminal (18) having a first end (50) proximate the first surface (32) of the
first housing (22) and a second end proximate the second surface (34) of the second
housing (24), the electrical connector being characterized in that:
the terminals (18) are configured to follow the shape of the terminal receiving
passages (12,14), such that bends (64) are provided in the terminals (18) to allow
high speed transmission of a signal transmission across the terminal (18) while minimizing
reflection of the signal, thereby ensuring that the high speed signal is properly
transmitted across the terminals (18) of the connector (22,24),
the first and the second housings (22,24) are metallized plastic such that the
properties of the surface layers of the first and the second housings (22,24) have
conductive characteristics;
dielectric sleeves (48) are coaxially positioned around the terminals (18),
portions of the sleeves (48) cooperate with walls of the passages (12,14) and with
the terminals (18) to provide spacing between the housing (22,24) and the terminals
(18), the dielectric sleeves (48) having spaces provided therein, the spaces providing
air gaps which allows the characteristic impedance to be such as to permit the high
speed signals to be transmitted properly across the terminals (18).
2. An electrical connector (22,24) as recited in claim 1 characterized in that the
first ends (50) of the terminals (18) are formed into a fork, the fork having arcuate
surfaces (60) on one side thereof, the surfaces (60) act as a lead-in when the electrical
connector (22,24) is mated to a mating electrical connector (26).
3. An electrical connector (22,24) as recited in claim 1 characterized in that the
dielectric sleeves (48) proximate the first end of the terminals (18) are cylindrical
in configuration.
4. An electrical connector as recited in claim 3 characterized in that the dielectric
sleeves 48 have projections (52,54) which cooperate with walls of the passages (12)
to provide an interference fit, maintaining the terminals (18) in the passages (12,14),
the projections (52,54) also providing an air gap over most of the length of the terminals
(18), allowing for controlled impedance.
5. An electrical connector (22,24) as recited in claim 1 characterized in that the
bends (64) are angles which are in the range from one hundred degrees to one hundred
seventy degrees.
6. An electrical connector assembly (2) for connecting conductive areas of a first
substrate (4) to conductive areas of a second substrate (6), the connector assembly
characterized in that:
a first electrical connector (22,24) having electrically conductive housing
means (22,24), the housing means (22,24) having at least one row of first terminal
receiving passages (12,14) extending from a first surface (32) of the housing means
(22,24) to a second surface (34) of the housing means (22,24), the terminal receiving
passages (12,14) having a bend therein, first terminals (18) located in the terminal
receiving passages (12,14) and having essentially the same configuration as the terminal
receiving passages (12,14), the first terminals (18) having a mating end (50) proximate
the first surface (32) of the housing means (22,24) and a board engagement end proximate
the second surface (34) of the housing means (22,24), dielectric means (48) surrounding
the first terminals (18) in the first terminal receiving passages (12,14), the dielectric
means (48) insulating the first terminals (18) from the housing means (22,24) and
providing spacing to properly position the first terminals (18) in the first terminal
receiving passages (12,14);
a second electrical connector (26) having electrically conductive housing member
means (26), the housing member means (26) having at least one row of second terminal
receiving passages (16) extending therethrough, second terminals (20) located in the
second terminal receiving passages (16), a mating end (88) of the second terminals
(20) cooperating with the mating end (50) of the first terminals (18), dielectric
material means (90) surrounding the second terminals (20) in the second terminal receiving
passages (16), the dielectric material means (90) insulating the second terminals
(20) from the housing member means (26) and providing spacing to properly position
the second terminal (20) in the second terminal receiving passages (16);
the housing means (22,24) and the housing member means (26) are metallized plastic
such that the properties of surfaces of the housing means (22,24) and housing member
means (26) have conductive characteristics; and,
the dielectric means (48) and the dielectric material means (90) have spaces
provided therein, the spaces provide air gaps which allow the characteristic impedance
to be such as to permit high speed signals to be transmitted properly across the first
and the second terminals (18,20).
7. An electrical connector assembly (2) as recited in claim 6 characterized in that
each connector (22,24,26) has power and ground busses (100,102,104,106) positioned
proximate outside surfaces thereof, the power and ground busses (100,104) of the first
connector (22,24) being in alignment with respective power and ground busses (102,106)
of the second connector (26) such that electrical engagement is provided between corresponding
busses when the connectors (22,24,26) are mated.
8. An electrical connector assembly (2) as recited in claim 6 characterized in that
camming means (118) is provided to cam the first terminals (18) of the first electrical
connector (22,24) into electrical engagement with the second terminals (20) of the
second electrical connector (26).
9. An electrical connector assembly (2) as recited in claim 8 characterized in that
a power and a ground bus (100,104) of the first electrical connector (22,24) is electrically
engaged to a respective power and ground bus (102,106) of the second electrical connector
(26) before the first terminals (18) of the first electrical connector (22,24) are
cammed into electrical engagement with the second terminals (20) of the second electrical
connector (26).
10. An electrical connector assembly (2) as recited in claim 6 characterized in that
the housing means (22,24) of the first connector (22,24) has two parts, a support
member (24) and a mating member (22), the bend occurring proximate the juncture of
the two members.