U.S. patent number 3,854,107 [Application Number 05/303,713] was granted by the patent office on 1974-12-10 for filtered connector.
This patent grant is currently assigned to The Bunker-Ramo Corporation. Invention is credited to Eugene S. Joseph, Jeff Tuchto.
United States Patent |
3,854,107 |
Tuchto , et al. |
December 10, 1974 |
FILTERED CONNECTOR
Abstract
Electrical connector including low-pass filter contact units
formed by inductance means of ferromagnetic material and
capacitance sleeve means of dielectric material on a central
conductive portion; the capacitive sleeve means is preferably
approximately the same diameter as the end portions of the contact
unit to provide a relatively thin unit while obtaining highly
effective filtering. The units are readily assembled and each unit
is independently removable from and re-installable in a contact
passage of a support body. Curved tines extend inwardly from
openings in a common ground plate to wipingly engage arcuately
spaced portions of an outer conductive sleeve during installation
and removal, insuring excellent electrical contact. Preferably, the
contact plate is of a thin resilient metal and is engaged by one or
two backing plates.
Inventors: |
Tuchto; Jeff (Don Mills,
Ontario, CA), Joseph; Eugene S. (Scarboro, Ontario,
CA) |
Assignee: |
The Bunker-Ramo Corporation
(Oak Brook, IL)
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Family
ID: |
26734785 |
Appl.
No.: |
05/303,713 |
Filed: |
November 6, 1972 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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55939 |
Jul 17, 1970 |
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860175 |
Sep 19, 1969 |
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584745 |
Oct 16, 1966 |
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Current U.S.
Class: |
333/183;
439/586 |
Current CPC
Class: |
H03H
1/0007 (20130101) |
Current International
Class: |
H03H
1/00 (20060101); H03h 007/04 (); H01r 013/66 () |
Field of
Search: |
;333/79
;339/59M,147R,21M,27R |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
Rowlands et al., "Suppressing Noise at the Connector," Electronics,
5-17-65, pp. 65-67..
|
Primary Examiner: Lawrence; James W.
Assistant Examiner: Punter; Wm. H.
Attorney, Agent or Firm: Bair; David R. Arbuckle; F. M.
Parent Case Text
This application is a continuation of our prior applications Ser.
Nos. 55,939, filed July 17, 1970; 860,175, filed Sept. 19, 1969;
and 584,745, filed Oct. 16, 1966, all abandoned.
Claims
What is claimed is:
1. In an electrical connector having a plurality of individually
removable and replaceable filtered contact units, a main support
body comprising a pair of blocks of insulating material secured to
each other and having a plurality of aligned contact passages
therethrough; and electrical ground contact means comprising a
planar layer of conductive material sandwiched between said pair of
blocks and having openings aligned with the passages in said
blocks; each of said filtered contact units including an elongated
contact pin and filter means including a cylinder of fragile
dielectric material, said contact pin having a first end portion
adapted for connection with a mating connector member, a second end
portion adapted for connection with an electrical conductor, and an
elongated central portion interconnecting said end portions; said
cylinder of fragile dielectric material having an outer diameter
only slightly less than the diameter of a corresponding one of said
support body passages and is positioned wholly within said support
body passage for protection against damage; means securing each of
said contact pins individually in said support body but allowing
removal in the direction of said second end portion and reinsertion
of each contact pin individually without requiring separation of
the blocks of insulating material; said cylinder of dielectric
material having a relatively thin foil conductive sleeve on the
outer surface thereof and a central through bore surrounding said
contact pin central portion; said electrical ground contact means
having surfaces extending into each of said passages and yieldingly
engaging the conductive sleeve on said filter means; said
cylindrical filter means having opposite ends retained inside said
support body when inserted for use and being removable without
requiring separation of the blocks of insulating material.
2. The electrical connector of clalim 1 wherein said electrical
ground contact means comprises a metal contact plate having
resilient tines extending into each of the openings therein and
slidingly engaging the conductive sleeve on said filter means.
3. An electrical connector comprising:
a main support body of insulating material having a plurality of
parallel contact passages therethrough;
a contact pin comprising an elongated conductive body having first
and second end portions adapted to meet with another contact pin
and to be secured to a wire conductor respectively, and an
elongated central portion interconnecting said first and second end
portions and being located within a support body passage;
impedance means including a cylindrical body of fragile dielectric
material surrounding the elongated central portion of said contact
unit and an outer relatively thin foil conductive sleeve on the
outer surface of said dielectric body; said cylinder of fragile
dielectric material having an outer diameter only slightly less
than the diameter of a corresponding one of said support body
passages and is positioned wholly within said support body passage
for protection against damage;
said contact pin being installable within said body means by
inserting said first end portion into one end of a passage to move
through said passage and to partially project from the opposite end
thereof and being removable by withdrawal in the reverse
direction;
means mounting said impedance means for insertion into and removal
from said support body;
ground contact means in said body mounted in surrounding,
contacting relationship with said outer conductive sleeve, and
making wiping contact with said outer conductive sleeve during
installation and removal of said impedance means; and
means for releasably locking said contact pin upon insertion of the
pin in said passage, said locking means being releasable to permit
withdrawal of said contact pin in said reverse direction.
4. The electrical connector of claim 3 wherein said body includes a
pair of blocks having aligned openings defining said passages, and
said ground contact means comprises a metal contact plate
sandwiched between said pair of blocks, said contact plate having
openings aligned with said passages in said pair of blocks, and a
plurality of angularly spaced, radially inwardly extending tines in
each of said openings thereof, said tines being curved for wiping
engagement with angularly spaced portions of the outer surface of
said outer conductive sleeve.
5. The electrical connector of claim 3 wherein said impedance means
has a central bore into which the elongated central portion of said
contact pin extends, and said contact pin further includes a pair
of collars located at opposite ends of said central portion, said
collars having diameters larger than the bore of said impedance
means.
6. The electrical connector of claim 5 wherein the diameter of said
outer conductive sleeve is approximately the same as the diameter
of said collars and only slightly less than the diameter of said
support body passage, and both of said collars are located in and
positioned by the walls of said support body passage when said
contact pin is locked in said passage.
7. In an electrical connector half that is useful in a two-part
connector system having a plurality of individually removable and
replaceable filtered contact units, said connector half including a
main support body comprising a pair of blocks of insulating
material secured to each other and having a plurality of aligned
contact passages therethrough; and electrical ground contact means
comprising a planar layer of conductive material sandwiched between
said pair of blocks and having openings aligned with the passages
in said blocks; each of said filtered contact units including an
elongated contact pin and filter means including a cylinder of
fragile dielectric material, said contact pin having a first end
portion adapted for connection with a mating connector in the other
part of said connector system, a second end portion adapted for
connection with an electrical conductor, and an elongated central
portion interconnecting said end portions; said cylinder of fragile
dielectric material having an outer diameter only slightly less
than the diameter of a corresponding one of said support body
passages and is positioned wholly within said support body passage
for protection against damage; means securing each of said contact
pins individually in said support body but allowing removal in the
direction of said second end portion and reinsertion of each
contact pin individually without requiring separation of the blocks
of insulating material, said cylinder of dielectric material having
a relatively thin foil conductive sleeve on the outer surface
thereof and a central through bore surrounding said contact pin
central portion; said electrical ground contact means having
surfaces extending into each of said passages and yieldingly
engaging the conductive sleeve on said filter means; said
cylindrical filter means having opposite ends retained inside said
support body when inserted for use and being removable without
requiring separation of the blocks of insulating material.
8. In an electrical connector half that is useful in a two-part
connector system having a plurality of individually removable and
replaceable filtered contact units, said connector half
comprising:
a main support body of insulating material having a plurality of
parallel contact support passages therethrough;
a contact pin comprising an elongated conductive body having first
and second end portions adapted to meet with another contact pin in
the other connector system part and to be secured to a wire
conductor, respectively, and an elongated central portion
interconnecting said first and second end portions and being
located within a support passage;
impedance means including a cylindrical body of fragile dielectric
material surrounding the elongated central portion of said contact
unit and an outer relatively thin foil conductive sleeve on the
outer surface of said dielectric body; said cylinder of fragile
dielectric material having an outer diameter only slightly less
than the diameter of a corresponding one of said support body
passages and is positioned wholly within said support body passage
for protection against damage;
said contact pin being installable within said body means by
inserting said first end portion into one end of a passage to move
through said passage and to partially project from the opposite end
thereof and being removable by withdrawal in the reverse
direction;
means mounting said impedance means for insertion into and removal
from said support body;
ground contact means in said body including a plurality of
angularly spaced, radially inwardly directed tines of conductive
material mounted in surrounding, contacting relationship with said
outer conductive sleeve, and making wiping contact with said outer
conductive sleeve during installation and removal of said impedance
means; and
means for releasably locking said contact pin upon insertion of the
pin in said passage, said locking means being releasable to permit
withdrawal of said contact pin in said reverse direction.
9. In an electrical connector having a plurality of individually
removable and replaceable filtered contact units, a main support
body comprising a pair of blocks of insulating material secured to
each other and having a plurality of aligned contact passages
therethrough; and electrical ground contact means comprising a
planar layer of conductive material sandwiched between said pair of
blocks and having openings aligned with the passages in said
blocks; each of said filtered contact units including an elongated
contact pin and filter means including a cylinder of fragile
dielectric material, said contact pin having a first end portion
adapted for connection with a mating connector member, a second end
portion adapted for connection with an electrical conductor, and an
elongated central portion interconnecting said end portions; means
securing each of said contact pins individually in said support
body but allowing removal in the direction of said second end
portion and reinsertion of each contact pin individually without
requiring separation of the blocks of insulating material; said
cylinder of dielectric material having a conductive sleeve on the
outer surface thereof and a central through bore surrounding said
contact pin central portion; said electrical ground contact means
having surfaces extending into each of said passages and yieldingly
engaging the conductive sleeve on said filter means; said
cylindrical filter means having opposite ends retained inside said
support body when inserted for use and being removable without
requiring separation of the blocks of insulating material, said
electrical ground contact means comprises a metal contact plate
having resilient tines extending into each of the openings and
slidingly engaging the conductive sleeve on said filter means; and
said contact pin securing means includes an enlarged, resilient,
bulbous member and an annular collar member spaced therefrom by a
predetermined distance, both of said members being located between
said first end portion and said central portion of said contact
pin; and said passageways have a first bore section having a first
diameter sufficiently large to pass said bulbous and collar members
and said cylindrical filter unit, and a second bore section of
reduced diameter sufficiently large to pass the first end portion
of said contact pin and to allow forced passage of said bulbous
member but not said collar member, said second bore section
extending along said predetermined distance between said bulbous
and collar members.
10. The electrical connector of claim 9 wherein the diameter of
said collar member is substantially the same size as the diameter
of the first bore section, the second end section of the contact
pin has a second collar member which has a diameter substantially
the same size as the diameter of the first bore section so that the
contact pin can be easily inserted and removed by hand, but not
wobbling therein or having appreciable play; and the filter means
is positioned between said collar members to be thereby removable
and insertable concomitantly with removal and insertion of the
associated contact pin.
11. The electrical connector of claim 10 wherein said fragile
cylindrical dielectric body has an outer diameter only slightly
less than the diameter of said support body passage and is
positioned wholly within said support body passage for protection
against damage.
12. In an electrical connector having a plurality of individually
removable and replaceable filtered contact units, a main support
body comprising a pair of blocks of insulating material secured to
each other and having a plurality of aligned contact passages
therethrough; said support body being enclosed within a metallic
housing comprising forward and rearward portions each having a
mounting flange formed integrally with both of said portions; an
electrical ground contact means comprising a planar layer of
conductive material sandwiched between said pair of blocks and
having openings aligned with the passages in said blocks; each of
said filtered contact units including an elongated contact pin and
a cylindrical filter means, said contact pin having a first end
portion adapted for connection with a mating connector member, a
second end portion adapted for connection with an electrical
conductor, and an elongated central portion interconnecting said
end portions; means securing each of said contact pins individually
in said support body but allowing removal in the direction of said
second end portion and reinsertion of each contact pin individually
without deleterious effects on said connector; said cylindrical
filter means having a conductive sleeve on the outer surface
thereof and a central through bore surrounding said contact pin
central portion; said electrical ground contact means comprising a
metal contact plate having resilient tines extending into each of
said passages and slidingly and yieldingly engaging the conductive
sleeve on said filter means; said metal contact plate having outer
peripheral edges which are clamped between the flanges of said
metallic housing to establish a low resistance electrical grounding
connection between the metal contact plate of the connector and the
mounting flange of said housing; said cylindrical filter means
having opposite ends retained inside said support body when
inserted for use and being removable without deleterious effects on
said connector.
13. In an electrical connector having a plurality of individually
removable and replaceable filtered contact units, a main support
body comprising a pair of blocks of insulating material secured to
each other and having a plurality of aligned contact passages
therethrough; an electrical ground contact means comprising a
planar layer of conductive material sandwiched between said pair of
blocks and having openings aligned with the passages in said
blocks; each of said filtered contact units including an elongated
contact pin and a cylindrical filter means, said contact pin having
a first end portion adapted for connection with a mating connector
member, a second end portion adapted for connection with an
electrical conductor, and an elongated central portion
interconnecting said end portion means securing each of said
contact pins individually in said support body but allowing removal
in the direction of said second end portion and reinsertion of each
contact pin individually without deleterious effects on said
connector; said cylindrical filter means having a conductive sleeve
on the outer surface thereof and a central through bore surrounding
said contact pin central portion; said electrical ground contact
means comprising a metal contact plate having resilient tines
extending into each of said passages and slidingly and yieldingly
engaging the conductive sleeve on said filter means, and a pair of
metal backing plates which are both thicker than said metal contact
plate, each of said backing plates having a large surface area
abuttingly engaged with opposite sides of said contact plate and
the abutting surfaces extending into close proximity to said tines;
the metal backing plates of the ground contact means extending
radially outwardly around the entire periphery of the insulating
material; and the connector further including an outer casing
having a surface portion of electrically conductive material
generally in a plane transverse to said contact passages and in
parallel facing and abutting relation to surface portions of at
least one of said metal backing plates which extend beyond the
periphery of the insulating material, and means establishing a low
resistance electrical connection between said metal backing plates
and said outer casing; said cylindrical filter means having
opposite ends retained inside said support body when inserted for
use and being removable without deleterious effects on said
connector.
Description
The present invention relates to a filtered connector.
A broad object of the invention is to provide a filtered connector
utilizing poke-home or removable contacts.
The connector is used in various installations such as, for
example, in instruments enclosed in a case or cabinet of conductive
material, such as aluminum. An external conductor or cable leads to
the cabinet and connects with the filtered connector and other
conductor or conductors lead from the connector to components
within the case. The case is grounded, and means are provided for
connecting the connector with the case and thus grounding it. The
connector filters out high frequency noise which is diverted to
ground, allowing only the direct current and low frequency
alternating current signals to pass through the connector.
Heretofore there has not been a successful and practical filtered
connector utilizing removable contacts.
Another and broad object of the invention is to provide a filtered
connector of poke-home character which has extremely good
electrical characteristics.
Another object is to provide a filtered connector of the foregoing
general character including pin contacts which can be easily and
quickly inserted in place and removed therefrom, and which can be
so inserted a great number of times without deletrious effects on
the connector.
Other objects of the invention are to provide a filtered connector
which is extremely small and inexpensive.
Other objects and advantges of the invention will appear from the
following detail description taken in conjunction with the
accompanying drawings in which:
FIG. 1 is a diagrammatic illustration of an instrument in which the
filtered connector of the present invention is incorporated, this
figure also showing the filtered connector itself;
FIG. 2 is a diagram of a filtering means of known kind and which is
incorporated in its essentials in the filtered connector of the
present invention;
FIG. 3 is a diagram of the same filtering means of FIG. 2 but
showing a modified arrangement of the elements and the specific
arrangement incorporated in the connector of the present
invention;
FIG. 4 is a perspective view of the main support structure of the
filtered connector;
FIG. 5 is also a perspective view of the main support structure but
taken from the side opposite that of FIG. 4;
FIG. 6 is a large scale sectional view taken at line 6-6 of FIG. 4
and also including a fragment of the cabinet in which the connector
is mounted; and
FIG. 7 is a face view of the contact plate incorporated in the
connector.
Referring now in detail to the drawings, attention is directed
first to FIG. 1 which shows the connector of the invention
incorporated in an instrument, at least portions of which are shown
diagrammatically. The connector is indicated as a whole at 10
mounted in a case or cabinet 12 of conductive material such as
aluminum, and grounded as indicated at 14. An external conductor 16
which is usually in the form of a cable detachably connects with
the connector through a plug 18 in a known manner. Other conductors
20 are connected with the pin contacts of the connector, as
referred to below, and lead to various instrumentalities in the
case 12.
The connector of the invention includes filtering means
incorporating the essentials represented in FIG. 2 where the
conductor 16 leads to an inductance means 24 and then to the
conductor 20 in the case. Capacitor means 25 are provided,
including capacitors 26 and 28 connected with the conductors 16 and
20 and then to a common conductor 30 representing the case 12, and
thereby to ground 14.
The filtering means shown in FIG. 3 is essentially the same as that
of FIG. 2 but includes rearranged elements according to their
arrangement in the connector of this invention. In the present
instance, the capacitor 26 includes a first plate 32, the capacitor
28 includes a first plate 34, and the two capacitors together have
a second and common plate 36, these plates being identified in the
connector in the description hereinbelow.
FIGS. 4, 5 and 6 show the details of the construction of the
connector. For convenience the connector will be identified as
including a main support structure 38 and a plurality of pin
contacts 40 removably mounted therein. The structure 38 includes an
outer block 42 and an inner block 44 of dielectric material of
known kind, preferably polycarbonate. Between the blocks is a
central plate or foil 46 of good conductive material and preferably
beryllium copper and of about .003 inches in thickness. This plate
or foil is interposed between a pair of other plates 48 preferably
of the same material but of substantially greater thickness, such
as about .010 inch. The blocks 42, 44 and the plates 46, 48 are
secured together in rigid assembly, as by housings or casings 50,
52 surrounding the peripheries of the respective blocks and having
flanges 54, 56 extending beyond the housings and secured together
as by rivets for securing the elements mentioned together. The
plates 46, 48 also extend beyond the blocks 42, 44 and preferably
to the edges of the flanges 54, 56 and are gripped therebetween.
The support structure 38 is mounted in an aperture 58 (FIG. 6) in
the case 12 and secured therein as by bolt-nut means 60 with the
adjacent flange 56 in good electrical contact engagement with the
wall of the case 12 so as to effectively ground the plate 46. Thus
the plates 48 minimize the electrical impedance and increase the
mechanical support.
The housing 52 preferably extends beyond the block 42 and forms a
socket 62 for receiving the plug 18 of the cable, in the usual
manner.
The structure 38 is provided with a plurality of through bores
which serve as apertures or pin cavities 64 removably receiving the
pin contacts 40, as well as other bores such as 65A, the following
description however referring to the through bores 44 which are
relatively large in number and of uniform size. The central through
bores extend perpendicular to the lamination and of course form
holes through all of the laminated elements. The size of the bores
64 relative to the pin contacts 40 are of importance and will be
referred to again hereinbelow. The bore 64 in the block 42 includes
a radially inwardly extending portion 67 and a counter-bore 68 at
the front side of the block opening to the front, forming a
forwardly facing shoulder 70. Inwardly of the portion 67 is another
counter-bore 72 forming an inwardly facing shoulder 74. The hole
has still another counter-bore 76 at its inner end extending to the
adjacent plate 48 which also has a hole, 78, preferably of the same
diameter as the counter-bore 76.
The hole in the block 44, designated 80, is of uniform diameter and
of the same diameter as the counter-bore 72. The adjacent plate 48
has a hole 82 of the same diameter as the hole 80, and thus of
smaller diameter than the hole 78 in the opposite plate 48. The
central plate 46 also has a hole, 84, which is best shown in FIG. 7
which also shows the face of the central plate or foil 46. It also
has holes 83 and 83A aligned with holes of the blocks 42, 44 to
form the aperture 67 of the apertures 66. Referring to the holes 84
these are formed by initially cutting or punching them in the form
of crosses, forming tines 86 which are then depressed or bent out
of the plane of the plate, and they assume a shape calculated for
producing a wiping action referred to below. That shape preferably
is as indicated in FIG. 6 which is generally arcuate and preferably
of a relatively long dimension in arcuate direction. It has been
found that the greater the number of tines, the greater will be the
effectiveness of the electrical contact between the tines and the
pin contact.
The pin contact 40, removably disposed in each of various and
selected ones of the apertures 64, as indicated, cooperates with
the various dimensions of the holes making up the aperture 64. The
pin contact 40 is made of good conductive material such as copper,
which for manufacturing purposes is made of two parts. The body
includes a central reduced portion 90 and end portions 98 and 94.
The end portion 98, or front end, is adapted for engagement with
the plug on the conductor 16 while the end portion 94, which may
also be considered to be a collar is connected with the conductor
20. The rear end portion 94 has a hole or socket 95 into which the
conductor 20 is inserted and is then crimped thereon for securement
thereto.
The pin contact 40 at its forward end includes an enlargement or
collar 96 forwardly of which is another reduced portion 98 forming
a pin received in the plug 18. A retainer clip 100 is fitted on the
pin 98 and secured thereto, adjacent to radially inwardly extending
portion 67, having a radially yieldable, outwardly biased
enlargement or bulbous portion 102.
After securing the conductor 20 to the pin contact 40, as
indicated, the pin contact is inserted into the aperture from rear
to front (right-to-left, FIG. 6), the retainer clip 100 collapsing
or contracting in the portion 67 of the aperture, this movement
continuing until the collar 96 engages the shoulder 74, whereupon
the bulbous portion 102 passes by this restricted portion of the
hole and expands, normally and yieldably retaining the pin contact
in the aperture. Such a structure serves as a means for the
insertion and removal of the pin contact and the impedance elements
from the passageway in the blocks 42 and 44 of insulating material
without separation of the blocks.
The inductance means 24 identified in FIGS. 2 and 3 is shown in
FIG. 6 in the form of a ferrule 104 of ferrite, preferably made up
of a plurality of sections butted end-to-end. This ferrule
surrounds the reduced central portion 90 and confined endwise
between the collar 96 and the rear end portion 94 which is secured
to central portion 90 in any suitable manner such as by crimping.
This ferrite ferrule produces an inductance in a known manner.
Outwardly of the ferrule 104 is a the capacitor means 25 identified
above which includes the plates 32, 34, and 36 and a dielectric
sleeve or cylinder 106 that has a central through bore and is made
of a rigid ceramic material that is quite fragile. The plates are
preferably of silver and may be a thin foil or coating applied to
the inner and outer surfaces of the dielectric cylinder 106, the
inner plates 32, 34 being spaced apart as indicated at 107 with end
flanges 108 and 110 engaging the body of the pin and specifically
the collar 96 and rear end portion 94. The outer plate 36 is of
substantial length and forms an outer exposed contact element for
engagement with the tines 86.
The physical construction of the pin contact is such that, from the
collar 96 inwardly or rearwardly, it is substantially and
effectively of uniform diameter. The dimensions of certain of the
elements represented in FIG. 6 are exaggerated, the plates 32, 34,
36 being of insignificant thickness from a physical standpoint
although however, of complete and uniform electrical integrity. The
diameter of this inner or rearward large portion of the pin contact
is only slightly less than the diameter of holes 80, 72 and in fact
so dimensioned that the pin can be easily inserted and removed by
the hand, but not wobbling therein or having appreciable play. As
an example of the dimensions involved, the pin contact at its
greatest diameter may be on the order of .085 inch, and .880 inch
long.
The tines 86 extend inwardly beyond the diameter of the pin and
upon insertion of the pin into the aperture, the outer capacitor
plate 36 engages the tines with complete electrical contact
therewith and to ground. The dimensions of the holes 80, 72 are
important from the standpoint of physically positioning the pin
contacts so that the pin element 98 is received in the plug 18
readily and without bending or distortion; it has the further
advantage of establishing good electrical contact between the outer
capacitor plate 36 and the tines 86. The counter-bore 76 provides
space for yielding of the tines, but this counter-bore is of
relatively small dimension axially. The tines 86 being biased
radially inwardly constantly engage the outer capacitor plate 36 at
all times; they produce a good wiping action thereon for good
contact engagement, and the plurality of them circumferentially
aids to the effectiveness of the contact engagement. The gripping
of the central plate or foil 46 between the plates 48, and
particularly the fact that they do so throughout the entire area
thereof, has been found to produce an exceptional electrical
conductive condition.
While a preferred form of the invention has been disclosed herein,
it will be understood that changes may be made therein within the
spirit and scope of the appended claims.
* * * * *