Note: Descriptions are shown in the official language in which they were submitted.
CA 02348233 2001-05-18
Docket No. WI 00-03
POWER CONNECTOR FOR
CONNECTION TO A PRINTED
CIRCUIT BOARD
Related Application
The present application claims priority of U.S. Provisional Application
Serial No. 60/205,253, filed May 19, 2000, entitled "POWER CONNECTOR
FOR CONNECTION TO A PRINTED CIRCUIT BOARD", the disclosure of
which is incorporated by reference herein in its entirety.
Field of the Invention
The present invention relates generally to electrical connectors, and more
particularly, electrical power connectors capable of carrying high current
from 50
amps to 1000 amps at low voltages from .5 volts to 48 volts.
Background of the Invention
Electrical power connectors are often needed to carry high current
between one circuit board and another circuit board. Electrical backplanes
frequently have multiple daughtercards connected to the backplane which
require
both signal and power connectors to make electrical connections between the
backplane and daughtercard. For example, a need exists in the art for a
connector
capable of carrying several currents between 125 amps to 950 amps at 1.5
volts,
1.8 volts and 2.5 volts.
Electrical backplanes frequently are populated with multiple
daughtercards. The daughtercards are connected to the backplanes using
electrical connectors known in the art. From time to time it becomes desirable
or
necessary to change daughtercards to either change the configuration of the
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electrical circuit contained on the daughtercard or to replace defective
daughtercards. The prior art does not adequately address a simple means for
providing high current power at low voltages to the daughtercard from power
supplies contained on the backplane. In addition, it would be desirable to
have an
electrical connector for providing power to a daughtercard from a backplane in
which the power connection between the backplane and the daughtercard is
effected simultaneously with inserting the daughtercard into the electrical
connector which transfers electrical signals between the backplane and
daughtercard.
Summary of the Invention
It is, therefore, an object of the present invention to provide a U-shaped
electrical power connector.
It is, therefore, an object of the present invention to provide an electrical
power connector capable of carrying high current from 50 amps to 1000 amps at
low voltages from .5 volts to 48 volts.
Another object of the present invention is to provide an electrical
conductor using a plurality of leaf springs or cantilever springs for carrying
current between a male and female connector.
Yet another object of the present invention is to provide an electrical
power connector for providing power from an electrical backplane to one or
more
daughtercards mounted on the backplane.
These and other objects of the present invention are achieved by an
electrical power connector including a U-shaped body including a first wall
with a
first plurality of undercut grooves and a second wall that has a second
plurality of
undercut grooves and a base member that has a third plurality of rectangular
slots.
A first plurality of spring contacts are each positioned in a corresponding
one of
the first plurality of grooves. A second plurality of spring contacts are each
positioned in a corresponding one of the second plurality of grooves. A third
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plurality of carrier mounted pins are each positioned in a corresponding one
of the
plurality of rectangular slots.
Still other objects and advantages of the present invention will become
readily apparent to those skilled in the art from the following detailed
description,
wherein the preferred embodiments of the invention are shown and described,
simply by way of illustration of the best mode contemplated of carrying out
the
invention. As will be realized, the invention is capable of other and
different
embodiments, and its several details are capable of modifications in various
obvious respects, all without departing from the invention. Accordingly, the
drawings and description thereof are to be regarded as illustrative in nature,
and
not as restrictive.
Brief Description of the Drawings
The present invention is illustrated by way of example, and not by
limitation, in the figures of the accompanying drawings, wherein elements
having
the same reference numeral designations represent like elements throughout and
wherein:
Figure 1 is a side elevational view of an electrical power connector
according to the present invention;
Figure 2 is a top plan view of an electrical power connector according to
the present invention;
Figure 3 is a cross-sectional view taken along lines 3-3 in Figure 2;
Figure 4 is a cross-sectional view taken along lines 4-4 in Figure 1;
Figure 4A is a side elevational view of the electrical power connector with
an electrically insulative cover; and
Figures SA and SB are top and bottom perspective views of a spring
contact according to the present invention.
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4
Best Mode for Carrying Out the Invention
Refer now to Figure 1 where a side elevational view of an electrical power
connector 10 according to the present invention is depicted. As illustrated,
the
electrical power connector 10 is depicted in an upright orientation although
it
should be understood that the electrical power connector 10 is usable in any
orientation. Accordingly, terms used herein such as "left", "right", "above"
and
"below" should be construed in a relative sense.
The electrical power connector 10 includes a generally U-shaped body 20
having a first upwardly extending wall 22 and a second upwardly extending wall
24. The body can be made from a high conductivity material, for example,
brass,
copper, aluminum, or a copper alloy material. The body 20, in one embodiment,
is of a unitary construction. In this embodiment, two electrical power
connectors
10 would be required with one connector being a positive terminal and the
other
connector being a negative terminal. A base member 26 connects walls 22 and
24. In addition, the length and width of the base member 26 can be varied
depending upon the amount of power to be transferred between the backplane and
daughtercard and the space requirements. The height of the walls 22, 24 of the
connector 10 can be varied to facilitate mechanical connection of the
daughtercard to the backplane. The base member 26 also has outwardly
extending shoulders 30, 32. A plurality of pins 40 extend downwardly from a
lower surface of base member 26. The C-Press pins 40 which may be used to
mount the connector to the backplane are described in U.S. Patent No.
4,017,143,
issued April 12, 1977 and a power connector using such pins is described in
U.S.
Patent No. 5,842,876, issued December l, 1998, both of which are hereby
incorporated by reference in their entirety into this specification. A row of
pins
40 are stamped from a unitary piece of metal. The pins 40 are connected to
each
other by a common carrier (not shown). The carrier is inserted into a groove
machined into the bottom surface of the base member 26. A staking process is
used to mechanically fasten the carrier and the pins 40 to the base member 26.
A
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soldering, brazing or other mechanical fastening process can be used. The
walls
22 and 24 each have an inner surface 50, 52, respectively, each having a
plurality
of opposed undercut horizontal grooves extending for the entire length of
walls
22, 24, as depicted in Figure 1. As depicted, wall 50 has undercut grooves 60,
62,
5 64 and surface 52 has undercut grooves 70, 72, 74. The undercut grooves 60,
62,
64 and 70, 72, 74 do not have to extend for the entire length of the walls 22,
24,
respectively. For example, the grooves 60, 62, 64 and 70, 72, 74 can stop
short of
the end of one wall to provide a positive stop to help to retain the springs
to the
walls. Although leaf springs are shown, other types of contacts can be used,
for
example, a cantilevered contact having a free end to make contact with the
mating
daughtercard connector.
The connector 10 operates by making contact with conductive surfaces on
the daughtercard inserted into it. For example, copper surfaces can be
laminated
onto one or both sides of the daughtercard to facilitate making a power
connection
between the backplane and the daughtercard. Note that both sides of the
daughtercard do not have to have conductive surfaces, depending on how much
power is to be transferred between the backplane and the daughtercard. Also
note
that the top portions of the walls 22 and 24 taper inwardly to guide a
daughtercard
into the aperture within the power connector when the daughtercard is being
inserted into the connector. It is also possible to have an insulating cover
over the
connector to prevent accidental electrocution. The cover would fit over the
entire
connector except, however, that it would have a slot along the top and side
edges
to accommodate entry of a daughtercard. One end of the insulator could be
closed if the power connector was placed in a position such that it made
contact
with power contacts on a far end of a daughtercard. A plurality of contact
springs
are retained in the undercut grooves 60-64 and 70-74.
The daughtercard (not shown) is inserted into the U-shaped area making
contact to the springs.
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As depicted in Figure 4, an undercut 60 is required to accept a latch from
an electrically insulating sheath 70 (see Figure 4A) for retention of the
sheath 70.
The sheath 70 is shaped so as to conform to the exterior surfaces of the U-
shaped
body 20. The sheath 70 can be formed of a glass filled thermoplastic
polyester.
The power handling capability of the power connector can be modified by
changing either the number of pins on the backplane and daughtercard sides of
the
power connector and/or the size of the pins and the plated through-holes on
the
backplane and daughtercard into which the pins are inserted. Also the wide and
length of the base member 24 and corresponding daughtercard portion 112 can be
sized to accommodate different numbers of pins and contacts and voltages and
currents. The pins can either be placed in the backplane and daughtercard by
friction fit into plate through-holes in the respective boards and/or can be
soldered
in place to effect a secure mechanical and electrical connection between
circuits
on the backplane and daughtercard through respective power connector portions.
Figures SA and SB depict a contact spring 300 according to the present
invention. The contact spring 300 is illustrative of the contact springs 80-94
discussed above. The contact springs are preferably formed from beryllium
copper or equivalent material with the appropriate mechanical and electrical
properties and can be stamped in a progressive die. The contact spring 300 has
a
pair of opposed longitudinal sections 301, 302. Joining the longitudinal
sections
are a plurality of spaced apart curved members 310, 336 which extend
transversely relative to the longitudinal sections 300, 302. The longitudinal
sections are retained in opposite undercut portions of the undercut grooves.
Each
of these flexible spring contacts 310, 336 forms an electrical contact point
between the male connector and the female connector. One benefit of the power
connector design utilizing multiple spring fingers of the type shown is to
effect a
tight electrical and mechanical connection between the two power connector
portions even though slight misalignment may occur between the backplane and
daughtercard.
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It should be appreciated that the electrical power connector shown and
described can assist in providing physical mounting rigidity between the
backplane and daughtercards and that multiple power connectors can be used for
one or more daughtercards mounted on a backplane depending on the amount of
power required for the daughtercard and to assist in providing mechanical
rigidity
between the backplane and daughtercard.
It will be readily seen by one of ordinary skill in the art that the present
invention fulfills all of the objects set forth above. After reading the
foregoing
specification, one of ordinary skill will be able to affect various changes,
substitutions of equivalents and various other aspects of the invention as
broadly
disclosed herein. It is therefore intended that the protection granted hereon
be
limited only by the definition contained in the appended claims and
equivalents
thereof.
