Note: Descriptions are shown in the official language in which they were submitted.
PATENT APPLICATION
FOR
INTERNALLY SWITCHED FEMALE RECEPTACLE OR CONNECTOR
WITH PLUG-LATCHING SAFETY INTERLOCK
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of provisional patent application No.
61/722,001, filed November 2, 2012.
FIELD OF THE INVENTION
This invention relates to electrical connectors, in particular to IEC
60309-2 configuration pin-and-sleeve (plug and receptacle) devices, which are
usually offered in amperage ratings 16/20A, 30/32A, 60/63 and 100/125A in
various voltage ratings and in various pin/sleeve configurations. These
products are used worldwide and are built and tested to IEC 60309-1 and -2
standards. They also are UL-Listed for North American applications under UL
standards 1682 and 1686.
BACKGROUND OF THE INVENTION
Standard pin and sleeve devices typically are comprised of a male plug
having "pins" and a female connector or receptacle (connected to a power
source) having mating sleeve-like contacts ("sleeves"). Some form of plug-to-
receptacle latching usually is provided at least to prevent accidental
separation
of those components. The electrical connection is made through the
mechanical insertion of the plug pins into the receptacle sleeves.
For safety reasons, the receptacle's sleeves must not be energized or
accessible unless a mating plug is properly and fully inserted. Several types
of
arrangements afford such protection:
Type I: These devices employ an apertured, plug-displaceable safety disc
that covers the "live" sleeves when no plug is present.
Type II: In these devices the sleeves are internally switched with respective
"live" inner contacts and are kept open when no plug is present to
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automatically provide an exposed "dead face" (see, e.g., U.S. Patent Nos.
4,659,160 and 4,488,765).
Type III: These devices add to the Type II arrangement an external actuator
for manually closing and opening the internal (sleeve and inner) switch
contacts only when the plug and the receptacle are joined and for
preventing their separation when the switch contacts are closed (see, e.g.,
U.S. Patent Nos. 4,140,358 and 4,678,254).
SUMMARY OF THE INVENTION
The invention generally concerns the Type II and Type III pin and sleeve
devices referred to above. As used in this application, the term "receptacle"
means the female half of a pin and sleeve device regardless of its means of
support or connection to a power source (e.g., surface-mount, in-wall or panel
mount, cable-connected, etc.).
Electrical receptacles according to the invention are for use with a
standard plug having a shroud surrounding a plurality of pins and an external
indexing tab on the shroud. Such a receptacle comprises a housing having a
= longitudinal axis, an axially facing outer end and an axially extending
cavity
open to the outer end for receiving the shroud and the indexing tab of a plug.
A releasable plug latch is carried by the housing and includes a catch movable
transversely of the axis between a capture position and a release position and
vice versa. The release position allows axial insertion and axial withdrawal
of a
plug and the capture position blocks withdrawal of a plug after at least
partial
insertion of the plug into the housing.
The receptacle also has a group of sleeve contacts and a group of inner
contacts. The sleeve contacts extend axially into the housing from its outer
end and are engageable through the outer end by respective pins of a plug.
The inner contacts reside in the housing remote from the outer end. At least
one of the groups of contacts is mounted for relative axial movement toward
and away from the other group to enable the sleeve contacts axially to engage
with and disengage from respective inner contacts.
7
Also included is a plug-activated interlock carried by the housing which
includes
at least one follower in the plug-receiving cavity displaceable by a plug
during its axial
insertion into the housing. The interlock keeps the sleeve contacts and the
inner contacts
disengaged when no plug is present in the housing, and enables engagement of
those
contacts during axial insertion of a plug into the housing only when the pins
of the plug
are substantially fully engaged with the sleeve contacts. Release of the plug
latch
disengages the sleeve contacts from the inner contacts and allows the plug to
be removed
from the receptacle.
The following features are combined in one embodiment. The sleeve contacts are
held in a carrier that is movable relative to the fixed inner contacts. The
catch is spring-
loaded toward its capture position, free-floating and configured to be
temporarily
displaced by an incoming plug tab, after which it snaps back to its capture
position
behind the rear end of the tab. A pass-through ground conductor ensures that
the primary
circuit is grounded even before the sleeve contacts and the inner contacts are
engaged.
An LED circuit powered through the sleeve contacts and the inner contacts
provides a
visual indication of the status of the device. A modular clocking design
having
peripheral knockouts enables variable angular positioning of the inner contact
support for
a variety of configurations.
In a broad aspect, the present invention pertains to an electrical receptacle
for use
with a plug having a shroud surrounding a plurality of pins and an external
indexing tab
on the shroud having a front end and a rear end. The receptacle comprises a
housing
having a longitudinal axis, an axially facing outer end, and an axially
extending cavity
open to the outer end for receiving the shroud and the indexing tab of the
plug. A
releasable plug latch carried by the housing includes a catch movable
transversely of the
axis, between a capture position and a release position and vice versa, the
release position
allowing axial insertion and axial withdrawal of the plug. The capture
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position blocks withdrawal of the plug after at least partial insertion of the
plug into the
housing. A group of sleeve contacts extends axially into the housing from the
outer end
and is engageable through the outer end by respective pins of the plug. A
group of inner
contacts in the housing is remote from the outer end, at least one of the
group of contacts
being mounted for relative axial movement toward and away from the other of
the groups
of contacts to enable the sleeve contacts axially to engage with and disengage
from
respective inner contacts. A plug-activated interlock carried by the housing
includes at
least one follower in the plug-receiving cavity displaceable by the plug
during axial
insertion thereof into the housing. The interlock keeps the sleeve contacts
and the inner
contacts disengaged when no plug is present in the housing, and enables
engagement of
the sleeve contacts and the inner contacts during axial insertion of the plug
into the
housing only when the pins of the plug are substantially fully engaged with
the sleeve
contacts.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention are described in detail below, purely by way of
example, with reference to the accompanying drawing figures, in which:
Fig. 1 is an exploded perspective view of a first receptacle embodiment
according
to the invention shown with a standard male plug;
Fig. 2 is a perspective view of the assembled receptacle and plug of Fig. 1;
Figs. 3 and4 are longitudinal sectional views thereof showing the sequence of
insertion of the plug into the receptacle of Fig. 1;
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Fig. 5 is a perspective view of a retaining mechanism of the receptacle of
Fig. 1;
Fig. 6 is a detail perspective view of the retaining mechanism of Fig. 5;
Fig. 7 is a detail sectional view of the retaining mechanism of Fig. 5;
Fig. 8 is a perspective view of the receptacle and plug of Fig. 1 with parts
removed showing the sequence of removal of the plug from the receptacle;
Fig. 9 is a longitudinal sectional view of the receptacle and plug of Fig. 1
showing the sequence of plug removal;
Fig. 10 is a bottom perspective view of the terminal retainer in the upper
housing of the receptacle of Fig. 1;
Fig. 11 is a perspective view of the receptacle and plug of Fig. 1 with
parts removed showing the status indicator circuit;
Fig. 12 is a longitudinal sectional view through the sleeve carrier
housing, sleeve carrier and terminal retainer of the receptacle of Fig. 1
showing
the sleeves separated from the pressure contacts;
Fig. 13 is a longitudinal sectional view of the receptacle of Fig. 1 similar
to Fig. 12 showing the sleeves engaging the pressure contacts;
Fig. 14 is a side elevational view of the receptacle of Fig. 1 with parts
removed showing details of the ground sleeve terminal;
Fig. 15 is an exploded perspective view of a second receptacle
embodiment according to the invention shown with a standard male plug;
Fig. 16 is a perspective view of the assembled plug and receptacle of Fig.
15;
Fig. 16A is a perspective view of the partially engaged plug and receptacle
of Fig. 15 with housing parts removed to reveal a retaining mechanism;
Fig. 17 is a detail perspective view of the retaining mechanism as seen in
Fig. 16A;
Fig. 17A is a longitudinal sectional view of the retaining mechanism as
seen in Fig. 17;
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Figs. 18A-18E are detail views of portions of the receptacle of Fig. 15
showing the sequence of insertion of the plug into the receptacle;
Figs. 19A-19C are detail views of portions of the receptacle of Fig. 15
showing the sequence of removal of the plug from the receptacle;
Fig. 20 is an exploded perspective view of a third receptacle embodiment
according to the invention shown with a standard male plug;
Figs. 21A-21C are detail views of portions of the receptacle of Fig. 20
showing the sequence of insertion of the plug into the receptacle;
Figs. 22A and 22B are detail views of portions of the receptacle of Fig. 20
showing the sequence of removal of the plug from the receptacle;
Fig. 23 is an exploded perspective view of a fourth receptacle
embodiment according to the invention shown with a standard male plug;
Figs. 24A-24G are detail views of portions of the receptacle of Fig. 23
showing the sequence of insertion of the plug into the receptacle;
Figs. 25A-25C are detail views of portions of the receptacle of Fig. 23
showing the sequence of removal of the plug from the receptacle;
Fig. 26 is an exploded perspective view of a fifth receptacle embodiment
according to the invention shown with a standard male plug;
Fig. 27 is a partial sectional view of the receptacle of Fig. 26;
Fig. 28 is a partial perspective view of the receptacle of Fig. 26 with some
parts removed;
Figs. 29-35 are detail views of portions of the receptacle of Fig. 26
showing the sequence of insertion of the plug into the receptacle;
Figs. 36 and 37 are detail views of portions of the receptacle of Fig. 26
showing the sequence of removal of the plug from the receptacle;
Fig. 38 is an exploded perspective view of a sixth receptacle embodiment
according to the invention shown with a standard male plug;
Fig. 39A is an cicvational view of the assembled receptacle of Fig. 38 and
a standard male plug;
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Figs. 39B-39E are detail views of portions of the receptacle of Fig. 38
showing the sequence of insertion of the plug into the receptacle;
Figs. 40A-40C are detail views of portions of the receptacle of Fig. 38
showing the sequence of removal of the plug from the receptacle;
Fig. 41 is an exploded perspective view of a seventh receptacle
embodiment according to the invention shown with a standard male plug;
Fig. 42A is an clevational view of the assembled receptacle of Fig. 41 and
a standard male plug;
Figs. 42B-42E are detail views of portions of the receptacle of Fig. 41
showing the sequence of insertion of the plug into the receptacle;
Figs. 43A-43C are detail views of portions of the receptacle of Fig. 41
showing the sequence of removal of the plug from the receptacle;
Fig. 44 is an exploded perspective view of a Type III embodiment
according to the invention shown with a standard male plug;
Figs. 45-47 are detail views, partly in section, of the actuator portion of
the receptacle of Fig. 44 in different states;
Figs. 48A-48E are detail views of portions of the receptacle of Fig. 44
showing the sequence of insertion of the plug into the receptacle;
Fig. 48F is a longitudinal sectional view through the partially mated plug
and receptacle of Fig. 44;
Figs. 49A-49E are detail views of portions of the receptacle of Fig. 44
showing the sequence of removal of the plug from the receptacle; and
Fig. 49F is a longitudinal sectional view through the fully mated plug and
receptacle of Fig. 44.
DETAILED DESCRIPTION OF IN THE INVENTION
As used in this application, terms such as "front," "rear," "side," "top,"
"bottom," "above," "below," "upwardly" and "downwardly" are intended to
facilitate the description of the invention and are not to be construed as
limiting the structure of the invention to any particular position or
orientation.
TYPE II EMBODIMENTS
6
Common Features
Reference is made by way of example to figures that show the first
embodiment. The same reference numbers denote the same or similar items in
figures that show the other embodiments. Referring to Figs. 1 and 2, a
standard male plug 1 for mating with receptacles according to the invention
has a cylindrical front safety shroud la surrounding a plurality of contact
pins
lb (four in the disclosed examples), which are adapted to mate respectively
with four contact sleeves ("sleeves" or "sleeve contacts") in the receptacle.
The
shroud has an integrally formed, radially projecting indexing rib or tab 1 c
at its
front end (referred to in IEC 60309 as part of the "major keyway") and a
rotatable locking ring ld having two lugs (not shown) adapted to mate with two
standard ramped locking flanges 2a at the front end of the receptacle's upper
housing 2. A standard butted rubber gasket (not shown) seals the interface
between the receptacle and the plug when they are fully mated. Each
receptacle embodiment also has a lower housing 36 secured by screws 38 to its
upper housing 2 with an interposed sealing gasket 35 (see Fig. 1). The lower
housing 36 shown is configured for connection to a cable. Upper housing 2 of
any embodiment can be mated instead to various adapters (not shown), using
screws 38, to enable mounting of the receptacle on a surface, in a wall, in a
panel, etc.
Referring to Figs. 1 and 12, three of the sleeves 8 (four in other
embodiments) have inwardly facing silver tips 8a and are axially movable into
and out of engagement respectively with the silver tips 18a of an equal number
of braided, spring-loaded contact terminals 18 (hereinafter "pressure
contacts"
or "inner contacts"). Referring to Figs. 1 and 10-13, the pressure contacts 18
are supported in a terminal retainer 15 by a terminal retainer cap 19 fastened
to retainer 15 by screws 20. Terminal retainer 15 is fixed to housing 2 by
screws 21. The pressure contacts are conventional: U.S. Patent No. 4,176,905,
which may be referred to for further details, shows a typical pressure contact
of
this type.
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First Embodiment (Figs. 1-14)
Referring to Figs. 1 and 12-14, the silver-tipped sleeves 8 of this
embodiment are fixed in a sleeve carrier 10, which is axially movable within a
carrier housing 3. The carrier housing is fixed in place by the abutting
terminal retainer 15 and its mounting screws 21. Two helical carriage springs
11 interposed between the sleeve carrier 10 and the terminal retainer 15 bias
the sleeve carrier away from the pressure contacts 18. Referring to Figs. 5-7,
sleeve carrier 10 has two diametrically opposed windows 40 that join
respective
narrower longitudinal slots 41 extending toward the terminal retainer. Two
inwardly deflectable, resilient retaining clips 7 are anchored near their
upper
ends in respective recesses 42 in the sleeve carrier (see Fig. 7). Each
retaining
clip 7 has an inclined, ribbed ramp portion 43 and a pair of lateral wings or
shoulders 44. When the retaining clips are in a relaxed state (not deflected),
their ramp portions 43 project outward through their respective windows 40 in
the carrier housing and their shoulders 44 engage the lower edges of their
respective windows, as shown in Figs. 5-7. In this state, the retaining clips
7
prevent downward movement of the sleeve carrier 10, keeping the sleeves 8
separated from the pressure contacts 18; and they project into the path
traveled by a plug shroud la.
Referring to Figs. 1-4, the upper housing 2 carries a latching mechanism
that interacts with the male plug's indexing rib (tab) lc during coupling and
uncoupling. The latching mechanism controls relative movement of the mating
parts and provides positive and audible engagement of the mating plug. The
latching mechanism includes a latch housing 30 and a latch housing cover 34
that house a "floating" latch or catch 32 biased inwardly by springs 33 toward
a latched or plug-capture position. In the capture position (see Fig. 4) the
catch projects into an indexing channel 47 (the other part of the IEC 60309
"major keyway") in which a plug pin 1 c travels. Catch 32 has a beveled
leading
surface (ramp) 45 and a flat trailing surface (shoulder) 46. When pressed, a
spring-loaded pushbutton (25, 26) acts against the lower end of a forked,
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medially pivoted toggle release lever 31 in latch housing 30 to pull catch 32
back, away from its capture position.
The pushbutton assembly is sealed to the housing by a button seal cup
27 and a button lip seal 28 and is surrounded on three sides by a U-shaped
rim 48 integrally formed with the upper housing 2. Rim 48 protects the
pushbutton assembly from damage yet provides sufficient space in the recess
around the pushbutton to keep dust and debris from accumulating in that
region. That feature and the sleek and watertight nature of the housing should
qualify such a receptacle as a NEMA 4X type enclosure, making it well-suited
for use in the food service industry and in other applications where moisture
and particulates are present.
Complete mechanical and electrical coupling of a plug and the receptacle
is accomplished by simple axial plug insertion, which triggers a sequence of
movements of the internal parts. Initial plug insertion yields mechanical
coupling only. The pins of the plug are mated with and pressed into the
respective sleeves of the receptacle, but the sleeves 8 and their carrier 10
are
held fast by the retaining clips 7 even as the leading edge (rim) of the plug
shroud la starts to deflect them radially inward (see Fig. 7). When the plug
pins are substantially fully seated in the sleeves 8 the retaining clips 7,
which
act as followers, have been deflected by the plug rim to the point that their
shoulders 44 have cleared the edges of the windows in the carrier housing 3,
freeing the carrier 10 to move downward.
Further insertion of the plug pushes the carrier 10 and its sleeves 8
toward the pressure contacts 18, compressing the carriage return springs 11.
As this occurs, the plug tab 1c contacts the ramp 45 of catch 32, displacing
the
catch until it audibly snaps back behind the plug tab with its trailing
shoulder
46 confronting the trailing end of the plug tab (see Fig. 3 and 4) to keep the
plug and the receptacle fully mated and to block plug withdrawal until the
catch is manually released. In this state, the pins are fully seated in the
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sleeves and the sleeves are in electrical contact with the tips of the
pressure
contacts, providing power to the plug and the primary electrical circuit.
The plug unlatching and removal sequence is illustrated in Figs. 8 and 9.
To remove the plug, the release (disconnect) pushbutton 25 is pressed to
release the catch 32, which then allows the return springs 11 to retract the
sleeve carrier 10. This action separates the sleeves 8 from the pressure
contacts 18 and at least partially ejects the plug, allowing complete plug
withdrawal. In the event the sleeves and the pressure contacts weld while
energized, they can be separated safely by holding the latch pushbutton in its
released state and pulling the plug and the receptacle apart.
This embodiment features a modular clocking design that enables
variable angular positioning of the terminal retainer 15 so that a variety of
terminal (pressure contact) configurations can be achieved during receptacle
manufacture without having to stock differently configured terminal retainers.
Referring to Fig. 10, upper housing 2 has a clocking key 50 facing the
periphery of terminal retainer 15, which has a plurality of peripheral
clocking
knockouts 51. The appropriate knockout 51 is broken out during receptacle
assembly depending on the terminal configuration specified for the unit. This
modular clocking feature is suitable for use in any of the type II embodiments
disclosed herein.
This embodiment also features a continuous ground design that ensures
grounding of the primary electrical circuit throughout plug insertion and
withdrawal. Referring to Figs. 1, 5, 11 and 14, one of the sleeves is in the
form
of a pass-through ground sleeve assembly 17 that, unlike sleeves 8, is not
supported in or moved by sleeve carrier 10 and has no silver tip on its inner
end. Instead, the ground sleeve assembly 17 is fixed in terminal retainer 15
and extends freely through sleeve carrier 10 where its distal (outer) begins
to
mate with a plug's ground pin upon initial plug insertion before the other
sleeves are engaged by their respective plug pins. Upon plug withdrawal, the
ground sleeve assembly is the last sleeve to disengage from its respective
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pin. Thus, the sleeve carrier moves along the fixed ground sleeve assembly the
ground connection does rely on a pressure contact. This continuous ground
feature is suitable for use in any of the embodiments disclosed herein.
This embodiment also features a plug/receptacle status indicator using
the primary circuit to power a low-current lighting control circuit. Referring
to
Figs. 1 and 11-14, two bridge connectors 9 transmit current from two line
sleeves 8 through top (4) and bottom (16) connection clips to respective top
and
bottom cylindrical contact rings 13 (each ring has two halves). Those rings
are
held in place on terminal retainer 15 by a contact ring holder 14. Two plug-in
printed circuit board (PCB) assemblies 12 with integral LEDs or other lighting
elements and lighting circuits are connected to and supported by the contact
rings, and each supports an LED lens 24 and an interposed lens gasket 23.
Closure of the primary electrical circuit upon full plug engagement with the
receptacle also closes the lighting control circuit, energizing the LED lamps.
The illuminated LED lamps are visible through observation windows 52 on
opposite sides of upper housing 2 (see Figs. 1 and 2), providing a visual
indication that power has been supplied to the plug. This status indicator
feature is suitable for use in any of the Type II embodiments disclosed
herein.
Second Embodiment (Figs. 15-19C)
The embodiment of Figs. 15-19C has essentially the same components as
the first embodiment, except for differences in the plug latching arrangement.
In this second embodiment, the receptacle upper housing has two latches 60,
61 instead of one, and they act tangentially rather than radially. Each latch
of
this embodiment similarly is spring-biased toward a latched position and has a
beveled leading surface (ramp) 62 and a flat trailing surface (shoulder) 63.
Each also has a release shaft and an external release button, which when
pressed moves the shaft and its latch against the spring force away from a
capture position. During plug insertion (see Figs. 16A-18E) the retaining
clips
function in the same way to temporarily hold the sleeves back from the
pressure contacts, but the two-latch design provides an intermediate retaining
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position. As a result, complete mechanical and electrical coupling of the plug
and the receptacle is accomplished in two stages through seamless, strictly
axial translation.
The first stage involves mechanical coupling only. On initial plug
insertion, the plug becomes parked and retained after passing the first latch
60, and the retaining clips 7 continue to immobilize the sleeves to prevent
them
from energizing. The second stage involves electrical coupling to energize the
sleeves and the mated plug pins. Specifically, further insertion of the plug
deflects the retaining clips 7, freeing the carrier housing 10 to move
downward
until the fully seated plug pins are energized through the fully displaced and
energized sleeves. The second stage is concluded when the second latch 61
springs back to capture the plug tab and the receptacle is fully mated.
The sequence of removal is also a two step process and is shown in Figs.
19A-19C. In the first step, depressing the second latch button 61 releases the
plug and partially ejects it to its intermediate parked position, where the
plug is
retained by the first latch 60 in a non-energized state. In the second step,
the
first button is depressed to release the first latch 60, allowing complete
withdrawal of the plug. Intermediate retention of the plug by the first latch
keeps the plug from inadvertently dropping to the floor during unplugging. In
the event the sleeves and the pressure contacts weld while energized, they can
be separated safely by holding the second latch in its released state and
pulling
the plug and the receptacle apart until the first latch arrests the
withdrawal.
Third Embodiment (Figs. 20-2213)
The embodiment of Figs. 20-22B has essentially the same components as
the second embodiment, but only one latch 64 (instead of two) that operates
tangentially. The latch is spring-biased toward a latched position and has a
beveled leading surface (ramp) 65; a flat trailing surface (shoulder) 66; a
release
shaft; and an external release button, which when pressed moves the shaft and
its latch against the spring force tangentially of the body and the plug.
During
plug insertion (Figs. 21A-21C), the retaining clips 7 function in the same way
to
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temporarily hold the sleeves back from the pressure contacts, but the single
latch does not retain the plug until the fully seated plug pins are energized
through the fully displaced and energized sleeves. During plug removal (Figs.
22A and 22B), depressing the latch button releases the plug, which is at least
partially ejected by the return springs to separate the sleeves from the
pressure
contacts.
Fourth Embodiment (Figs. 23-25C)
As compared to the second embodiment, this fourth embodiment has the
same pressure contact arrangement, but it has a different sleeve carrier and
sleeve carrier housing arrangement, which nevertheless function in a similar
manner. This third embodiment also has two spring-loaded, button-actuated
latches 70, 71 that control plug movement, but they operate in a somewhat
different manner as compared to the first embodiment. Referring to Figs. 24A-
24D, the first (upper) latch 70 has the same type of beveled leading surface
(ramp) and is automatically displaceable by the plug tab, but it does not
latch
over (capture) the plug tab during the initial phase of plug insertion. The
second (lower) latch 71 has fiat top and bottom surfaces 72, 73.
Referring to Fig. 23, the sleeve carrier 76 of this embodiment has two
integral, diametrically opposed arms 78 that project laterally through
respective axial guide slots 79 in the sleeve carrier housing 77. A single
large
helical carriage return spring 80 biases the sleeve carrier 76 away from the
pressure contacts 18. Referring to Figs. 23-24G, an L-shaped, axially movable
safety plunger is biased by a helical spring 83 toward the front end of the
receptacle upper housing. The safety plunger has a plug-engageable upper leg
84 and a lower leg 85 that blocks lateral actuating movement of the second
latch until the rim of the inserted plug has moved past the first latch and up
to
the second latch, which blocks further insertion of the plug. At this point
the
plug pins are fully engaged with the sleeves and the plug rim has displaced
the
safety plunger so that its lower leg no longer blocks the second latch (see
Fig.
24D). Actuation of the now freed second latch 71 (Fig. 24E) unblocks the plug
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and allows its rim to engage the sleeve carrier arms 78. During final
insertion
of the plug (Figs. 24F and 24G), the carrier and its sleeves are forced toward
the pressure contacts, compressing the carriage return spring and bringing the
sleeves into electrical contact with the tips of the pressure contacts. At
this
point the second latch 71 snaps over the plug tab, locking the plug to the
receptacle in the energized state (see Figs. 24F and 24G).
The sequence of removal (unplugging) is a two-step process and is shown
in Figs. 25A-25C. First, the second button is pressed to release the second
latch 71, which allows the return spring 80 to retract the sleeve carrier,
separating the sleeves from the pressure contacts and partially ejecting the
plug to the point where it is retained by the first latch 70 in a non-
energized
state. In the second step, the first button is pressed to release the first
latch
70, allowing complete withdrawal of the plug.
Fifth Embodiment (Figs. 26-37)
This embodiment has the same pressure contact arrangement as the
second embodiment (see Fig. 26). It also has essentially the same two-latch
arrangement as the second embodiment, except that the external actuators are
toggle buttons pivoted to the receptacle housing (see Fig. 33) instead of
wholly
shaft-supported round boots. It mainly differs from the other embodiments in
that the individual sleeves move, in unison, relative to a fixed sleeve
carrier 91
during plug insertion and removal. Also, unlike the other embodiments, the
internal components of this fifth embodiment (see Fig. 26) are mated to the
upper receptacle housing 88 through its open front end, rather than to its
underside.
Referring to Figs. 26-28, each contact sleeve 90 is part of an assembly
that includes a sleeve holder 92 and a leaf spring-loaded (94), outwardly
biased
wedge 93. The bottom of the wedge normally abuts blocking shoulders 97 near
the sleeve carrier's outer edge, the wedges thus positively holding the sleeve
holders and their sleeves at the sleeve carrier's front (mating) end. The
sleeve
holders are coupled together by an anti-tamper ring 95 - which also ensures
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their simultaneous movement when released - and they are biased toward the
front end of the sleeve carrier by a common encircling coil return spring 96.
Complete mechanical and electrical coupling of the male plug and the
receptacle is accomplished in two stages through seamless, strictly axial
translation of those parts. The first stage involves mechanical coupling (see
Figs. 27, 28 and 33) whereby the pins of the plug are mated with and pressed
into the respective sleeves of the receptacle. About half way through
pin/sleeve
engagement the rim (leading edge) of the plug contacts the sleeve-holding
wedges 93 (see Fig. 29). As the engagement continues, the plug shroud rides
over the tapered outer surfaces of the wedges, displacing the wedges radially
inward until they clear the blocking shoulders of the sleeve carrier (see Fig.
30).
Meanwhile, the plug tab has engaged the ramp of the first latch, deflected the
latch sideways and moved past it, whereupon the first latch has snapped back
audibly so that its trailing shoulder blocks the trailing end of the plug tab
(see
Fig. 34). Thus, at the end of the first stage, the first latch retains the
male plug
in the body with the pins and the sleeves fully engaged (see Fig. 30); but the
sleeves remain spaced from the pressure contacts, leaving the assembly
physically coupled but with the plug in a non-energized state.
The second stage involves electrical coupling to energize the plug. With
the sleeve-holding wedges 93 now clear of the blocking shoulders 97, further
axial mating of the plug with the receptacle drives the sleeve holders 92 and
their sleeves inward within the fixed carrier and along grooves 98 on the
outside of the terminal carrier 99, bringing their silver tips into engagement
with the silver tips of the pressure contacts (see Figs. 31 and 32).
Meanwhile,
the coil return spring 96 has been compressed; and the plug tab has engaged
the ramp of the second latch, deflected that latch sideways and moved past it,
whereupon the second latch has snapped back audibly so that its trailing
shoulder blocks the trailing end of the tab (see Fig. 35). Thus, at the end of
the
second stage, the second latch retains the plug in the body with its pins in
an
energized state.
CA 02832065 2013-11-01
Uncoupling (removal) is a two-step process. First, the second button is
pressed to release the second latch, which allows the coil return spring (not
shown in Figs. 33-37) partially to eject the plug to the point where it is
retained
by the first latch (see Fig. 36). In this position the silver contact tips are
separated, leaving the plug in a non-energized state. In the second step (see
Fig. 37), the first button is pressed to release the first latch, allowing
complete
withdrawal of the plug.
Sixth Embodiment (Figs. 38-40C)
This embodiment is substantially identical to the second embodiment in
structure and operation except for the latching arrangement, which can be
used in any embodiment that requires two latches. Referring to Figs. 38, 39A
and 39B, the latches are arranged for operation from only one side of the
device
by means of a three-position toggle 102 pivoted at its center to the side of a
latching module 100, which is mounted to the receptacle housing and includes
the latches, latch springs, latch guides and a latch cover. Each end of the
toggle 102 bears against the head of a respective toggle actuator screw 104,
the
threaded end of which is connected to a respective latch. Pressing on the
lower
portion of the toggle during plug removal actuates the second latch (see Fig.
40A); pressing on the upper portion of the toggle actuates the first latch
(see
Fig. 40C). The neutral position of the toggle is shown in Fig. 40B. As in the
second embodiment, the latches are actuated automatically during plug
insertion (see Figs. 39B, 39C, 39D and 39E).
Seventh Embodiment (Figs. 41-43C)
This embodiment is substantially identical to the sixth embodiment
except for a slightly different latching module 110, which can be used in any
embodiment that requires two latches. Referring to Figs. 41, 42A and 42B,
external button-headed pistons 112 on the latching module bear against the
end portions of an internal toggle plate 114, the opposite sides of which bear
against the heads of respective actuator screws 116 that are attached to the
respective latches. Pressing on the lower button during plug removal actuates
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CA 02832065 2013-11-01
the second latch (see Fig. 43A); pressing on the upper button actuates the
first
latch (see Fig. 43C). The neutral position of the toggle plate 114 is shown in
Fig. 43B. As in the sixth embodiment, the latches are actuated automatically
during plug insertion (see Figs. 42B, 42C, 42D and 42E).
TYPE III EMBODIMENT (FIGS. 44-49F)
Referring to Fig. 44, this receptacle embodiment includes within its
housing four braided, spring-loaded pressure contacts 18 (as described
previously) supported by a terminal retainer 19 in a terminal housing 15. Four
sleeves 8 are carried in a sleeve contact carrier assembly (top 122 and bottom
123). Also included are an axially movable terminal drive plate 125, a
rotatable
cam wheel 126 and two spring-loaded safety plungers 127. One side of the
receptacle's upper housing has an actuator assembly 130 that includes:
a) An actuator knob 132 with a LOTO (lockout/tagout) hoop feature and a
sealed rotary shaft/pin retaining/drive assembly 134 with a plug locking
feature;
b) Two spring-loaded sliding side rails 136; and
c) A face-sealing gasket 137 and a retainer plate 138 with LOTO feature
and markings with ON & OFF text for intuitive use.
Further structural details and operation of this embodiment are as follows and
as illustrated and described in Figs. 45-49F.
A drive pin of the actuator assembly transmits rotary ON/OFF knob
action in the X-Y plane to the cam wheel, which rotates in the X-Z plane. The
cam wheel has a ramp on the face of an X-Z plane which extends down the Y
axis and interfaces with an opposing ramp on the face of a terminal drive
plate,
also in the X-Z plane. As the cam wheel rotates, the angled surfaces convert
the rotary action into linear Y axis translation of the terminal drive plate,
which
moves the braided, spring-loaded pressure contacts simultaneously, making or
breaking the circuit with the respective sleeve contacts. The ground terminal
always breaks last and makes first. Clockwise rotation of the cam wheel (when
17
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viewed from the plug end) raises the terminal drive plate; counterclockwise
rotation of the cam wheel lowers the terminal drive plate.
The bottom sleeve contact carrier is a fixed component that contains a
center spline, which provides dielectric insulation between adjacent contacts
and linear Y-axis guiding and bearing surfaces between the spline and mating
features on the terminal drive plate. Bearing surfaces on the terminal drive
plate are optimized to minimize cocking potential and sliding friction.
Surface
contact area between the spline and the terminal drive plate is limited to the
mid-plane of the terminal drive plate thickness, where a radius and clearance
reliefs define hourglass sections in Y-Z and X-Z planes.
The two safety plungers, when actuated by the rim of a plug, allow cam
wheel rotation. When no plug is present, the plungers restrict any cam wheel
or knob rotation by filling respective slots in the cam wheel. The plungers
ensure that the receptacle cannot be turned "ON" until the mating plug has
been fully inserted. Plug insertion pushes the plungers to a depth along the Y
axis where they no longer block the slots in the cam wheel.
The knob-driven rotary shaft assembly consists of a shaft and a plate
with the drive pin at its lower end (which engages the cam wheel) and a U-
shaped latching/locking feature (hook or catch) at its upper end. When the
plug is fully inserted in the housing, a turn of the knob to the "ON" position
moves the catch transversely of the Y-axis to capture the trailing end of the
plug tab (see Fig. 49C).
The rotary ON/OFF knob drives an actuating cam, which is attached to
the receptacle housing on an X-Y plane and rotates about the Z-axis. The
actuating cam has a 4-pointed star-shaped profile that interfaces with
movable, spring-loaded side rails contained in the housing that slide along
the
X-axis. As the knob turns, the larger pointed cam features contact and
displace the spring-loaded side rails outwardly; then the smaller features
between the points allow the rails to move inwardly again. This cam profile,
when combined with the side spring loading, creates a torsional loading that
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CA 02832065 2013-11-01
accelerates the final rotation of the knob past the center point of the rotary
deflection, resulting in a snapping over or "over-center" knob action. The
over-
center knob action also provides resistance to vibration and inadvertent knob
rotation. The torsional spring loading about the Z-axis is transmitted to the
cam wheel and the terminal drive plate to provide quick Y-axis
loading/unloading of the butt contacts to make/break the circuit quickly,
minimizing arcing potential.
While exemplary embodiments have been chosen to illustrate the
invention, it will be understood by those skilled in the art that various
changes,
modifications, additions, and substitutions are possible, without departing
from the scope and spirit of the invention. Additions could include additional
or other types of arrangements that provide an indication of the status of the
device. For example, the receptacle could have an LED lead frame assembly
including resistors that reduce the line voltage to equal the operating
voltage
and load of the LED and maximize its life expectancy. Leads from the resistors
would be terminated to terminals of the braided pressure contacts on one end
and terminated to sleeves on the opposite end. An LED indication would occur
in any of the following scenarios:
(I) LIGHT CHANGES COLOR: Power applied and internal switching
mechanism de-energized, LED indicator displays "Green" or similar for "all
clear" indication. Internal switching mechanism then energized, LED
indicator displays "Red" for "hot" indication.
(2) LIGHT CHANGES STATE FROM DARK TO ILLUMINATED: Power
applied and internal switching mechanism de-energized, LED indicator
displays no light (similar to when main power is disconnected). Internal
switching mechanism then energized, LED indicator displays "Red" for "hot"
indication or "Green" to indicate circuit is active.
All indicator schemes would be supported by icons or text on the receptacle
housing to facilitate communication of the product function to the user. The
LED indication provides product users with immediate feedback on the power
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status of the switched connector, including whether the contacts weld while
energized, which would require prompt corrective action. The indication would
be visible from a distance, facilitating maintenance and start-up.
Alternatively or in addition, status indication could be accomplished in a
mechanical fashion. For example, the receptacle could have a visual indicator
such as a sliding or rotating colored panel or a colored sleeve collar riding
over
a colored drum or sphere. Where a movable colored outer panel or surface
covers an inner panel or surface, a contrasting color could be used to
designate
the changing state of power.
