U.S. patent application number 12/639636 was filed with the patent office on 2010-06-17 for housing for sensor interface electronics.
This patent application is currently assigned to K-TEK CORP.. Invention is credited to Eric Fauveau.
Application Number | 20100148643 12/639636 |
Document ID | / |
Family ID | 42239658 |
Filed Date | 2010-06-17 |
United States Patent
Application |
20100148643 |
Kind Code |
A1 |
Fauveau; Eric |
June 17, 2010 |
Housing for Sensor Interface Electronics
Abstract
The invention is an improved housing for storage of an
electronics interface package. The housing is attached to a sensor
adaptor or connector, and rotatable about that sensor adaptor. The
interface package is contained in the interior of the housing, and
is orientatable in the interior to provide different angles of
view.
Inventors: |
Fauveau; Eric; (Baton Rouge,
LA) |
Correspondence
Address: |
JONES, WALKER, WAECHTER, POITEVENT, CARRERE;& DENEGRE, L.L.P.
5TH FLOOR, FOUR UNITED PLAZA, 8555 UNITED PLAZA BOULEVARD
BATON ROUGE
LA
70809
US
|
Assignee: |
K-TEK CORP.
Prairieville
LA
|
Family ID: |
42239658 |
Appl. No.: |
12/639636 |
Filed: |
December 16, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61138004 |
Dec 16, 2008 |
|
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|
Current U.S.
Class: |
312/223.1 ;
220/327; 220/377 |
Current CPC
Class: |
G01F 23/00 20130101 |
Class at
Publication: |
312/223.1 ;
220/327; 220/377 |
International
Class: |
A47B 81/00 20060101
A47B081/00; B65D 45/30 20060101 B65D045/30; B65D 51/24 20060101
B65D051/24 |
Claims
1. A housing comprising a housing body having an exterior surface
and an interior defining a module compartment, said module
compartment having a sidewall, a bottom, and an open top; a cover
for said open top of said module compartment; an electronic module
positioned in said module compartment; a first port in said
housing, said first port connecting said module compartment to the
exterior surface of said housing; a sensor connector connected to
said housing body at said first port; a sensor connected to said
sensor connector; said module operationally connected to said
sensor; said housing having a means to allow said sensor connector
to rotate about said housing body within a predetermined fixed
range.
2. The housing in claim 1 wherein said fixed range is about 360
degrees.
3. A housing comprising a housing body having an exterior surface
and an interior defining a module compartment, said module
compartment having a sidewall, a bottom, and an open top; a cover
for said open top of said module compartment; an electronic module
positioned in said module compartment, a first port in said
housing, said first port connecting said module compartment to the
exterior surface of said housing, a sensor connector connected to
said housing body at said first port, a sensor connected to said
sensor connector, said module operationally connected to said
sensor; said housing having a means to fix the position of the
module in the module compartment at a selected one of several
positions.
4. A housing comprising a housing body having an exterior surface
and an interior defining a module compartment, said module
compartment having a sidewall, a bottom, and an open top; a cover
for said open top of said module compartment; an electronic module
positioned in said module compartment, a first port in said
housing, said first port connecting said module compartment to the
exterior surface of said housing, a sensor connector connected to
said housing body at said first port, a sensor operationally
connected to said sensor connector, said module operationally
connected to said sensor; said module fixedly engagable with said
module compartment at a selected discrete number of positions.
5. The housing compartment in claim 3 further having a module
holder rotatably mounted in said module compartment, said module
mounted in said module holder, said module holder and said module
compartment cooperating to fixedly engage said module compartment
at a selected finite number of positions.
6. A housing comprising a housing body having an exterior surface
and an interior defining a module compartment, said module
compartment having a sidewall, a bottom, and an open top; a cover
for said open top of said module compartment; an electronic module
positioned in said module compartment; a first port in said
housing, said first port connecting said module compartment to the
exterior surface of said housing; a sensor connector connected to
said housing body at said first port; a sensor connected to said
sensor connector; said module operationally connected to said
sensor; said housing rotatable about said sensor connector in a
fixed range.
7. A cover for a explosion proof housing body opening, said cover
comprising an annular threaded ring, said threaded ring having an
opening therethrough and a top rim around said opening, and an
interior surface; said cover including an locking ring having an
outer periphery portion, said outer periphery portion engaging said
interior surface of said threaded ring whereby said engaged locking
ring forms a gap substantially between the circumference of said
inner surface of said cover and said locking ring; a glass portion
sized to fit in said interior surface of said threaded ring and
retained by said rim; said glass portion positioned between said
rim and said locking ring, and said locking ring adapted to retain
said glass adjacent said rim.
Description
[0001] This application claims the benefit of provisional
application for patent Ser. No. 61/138,004 filed on Dec. 16, 2008,
which is incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
[0002] Many field processes use sensors located within the process
environment, such as level sensors. These sensors are generally
directly mounted in a tank or process line, or a portion of a
sensor mounted to the outside of a tank that works in conjunction
with a portion of the sensor in the tank (such as a magnetic level
sensor that operates in conjunction with a magnetic float in the
tank). The sensors are electrically connected to an electronic
interface package which is stored in a housing to protect the
electronics from the ambient environment. In a direct mount
package, the sensor protrudes from the tank, and the housing mounts
via a sensor adaptor or connector to the sensor. In other
applications, a cable may be routed from the sensor through conduit
to the housing holding the electronics. Power is generally provided
to the housing as required for operation of the sensor and
electronics. The housing may need to be mounted in a particular
configuration, for instance, at the top of a process tank, at the
bottom of a process tank, on the side of the process tank or offset
from the process tank by a desired angle. See FIG. 11. Many sensor
interface packages include components that provide manual
interaction with the sensor at the housing, such as a visual
indicator of the sensor readings (display screen or an alpha
numeric display), or an input apparatus (such as a keypad or cable
plug) to operate the sensor in manual mode, enter a calibration
sequence, or invoke other functionality. When the sensor interface
package includes such interactive components, the housing must be
orientable to allow the user to access or view the interactive
components. The most common manner to provide the needed degree of
housing orientation is to have a separate housing model or
construction for each needed orientation or installation. Shown in
FIG. 11 is multiple orientations for the housing/sensor package,
including sensor 100 (here a long probe), the housing 110, and a
connector 120 between the housing and sensor. As shown in FIG.
11a-j, multiple mounting configurations are possible, but many
require a different housing model to provide for bottom mount, top
mount, or left/right side mount. The manufacturer will typically
assemble and ship the unit as a package (sensor/housing/connector)
based upon the customer's ordered configuration, to keep the unit's
inner electronics being unnecessarily disturbed by the
customer.
[0003] The need to account for multiple mounting orientations
requires that the manufacturer stock multiple models of the
housing/adapter. Stocking multiple embodiments for the housing is
inefficient. As can also be seen in FIG. 11, the housing 110
includes a view window 130 to allow an operator to view or operate
the interactive components in the housing, such as a display. As
can be seen, the orientation of that window 130 can be right-side
up, upside down, left or right facing (e.g. sideways), depending on
the mounting configuration. This makes viewing the display, for
instance, difficult.
SUMMARY OF THE INVENTION
[0004] The invention is an improved housing for storage of an
electronics interface package. The housing is attached to a sensor
adaptor or connector, and rotatable about that sensor adaptor. The
interface package is contained in the interior of the housing, and
is orientatable in the interior to provide different angles of
view.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a perspective view of one embodiment of the
housing
[0006] FIG. 2 is a side cross section through the housing of FIG.
1. shows a cross section through one embodiment of the housing of
the present invention.
[0007] FIG. 3 is a cross section through the housing, but a
perspective of the corresponding connector.
[0008] FIG. 3 detail is a view of FIG. 3 showing an alternative
embodiment.
[0009] FIG. 4A is a perspective view of the housing showing the
interior of the module compartment with an L shaped member
installed in the compartment.
[0010] FIG. 4B is a perspective view of the housing showing the
interior of the module compartment with an electronic module holder
installed in the compartment.
[0011] FIG. 5A is a side view of the electronic module holder.
[0012] FIG. 5B is a bottom view of the electronic module
holder.
[0013] FIG. 6A is a perspective view of one embodiment of an
electronic module top.
[0014] FIG. 6B is a bottom view of an electronic module base.
[0015] FIG. 6C is a perspective view of one embodiment of a module
puller.
[0016] FIG. 7 is a cross section through the module compartment
showing the installed components.
[0017] FIG. 8A is a perspective view of one embodiment of viewing
glass cover for the module compartment.
[0018] FIG. 8B is a perspective view of one embodiment of a glass
cover retainer ring
[0019] FIG. 8C is a cross section through one embodiment of a
viewing glass cover for the interface electronic module
compartment.
[0020] FIG. 9 is a perspective view of the interior of the terminal
compartment.
[0021] FIG. 10 is a cartoon depicting movement of the wiring in the
interface component.
[0022] FIG. 11 is a front view of several prior art mounting
orientations of housing/sensor/connector.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Shown in FIG. 1 is a prospective view of one embodiment of
the housing. The housing body will generally be formed from cast
stainless steel or aluminum, if used as an explosion proof housing,
or it may be formed from a cast rigid plastic material that is
non-reactive with the environment otherwise. As shown, the housing
includes a body 1 that contains an interior that is partitioned
into two compartments, an module compartment 10, and a terminal
compartment 30. The two compartments are preferred but are not
necessary. A single compartment could be used if the module
compartment contained a terminal strip or a matching plug or socket
to accommodate incoming wiring, sockets or plugs, or other cable
connector.
[0024] As shown in FIG. 1, both compartments have an opening that
may be closed with removable covers 11 and 31. As depicted in the
housing cross section of FIG. 2, the module compartment 10 and
terminal board compartment 30 are stacked, one above the other,
with the two openings into the compartments orientated at an angle
of about 75 degrees to each other. Other angles may be used
depending of the specific housing design. A first channel 21
connects the two compartments, while a port 22 provides for entry
into the module compartment. Terminal compartment 30 includes one
or more ports 23 providing wiring access to the terminal
compartment via attachable conduit to the port 23.
[0025] Removably mating with the housing 1 is a sensor connector 50
(shown in FIG. 3). As shown sensor adapter is hollow right angle
tube that is threadable into port 22 in the housing. The sensor
connector 50 may be a straight connector or a connector formed with
any desired angle. The sensor will generally directly attach to the
sensor connector at opening 53 (such as a sensor top threading into
opening 53). Alternatively, a conduit may be attached to opening 53
and be routed to the sensor 100. In any event, wiring will
operationally connect the sensor with equipment located in the
housing (such as the module, later described). Located at the
opposite end of the sensor connector 50 is an upstanding finger 51.
As shown, upstanding finger 51 projects upwardly from the rim of
the threads 50A. When the sensor adapter 50 is threaded into the
port 22, the finger 51 projects into module compartment 10 or is
adjacent the interior of the module compartment 10. The sensor
connector 50 also has a slot 50.1 to accommodate a sealing ring,
such as an "O" ring. A set screw may be used through housing 1 to
contact and set the degree of rotation of the sensor connector 50
with respect to the housing 1. However, because the fit of the
sensor connector 50 to the housing 1 is designed to be a tight fit,
a set screw, clamp or other means to fix the position of the sensor
connector may not be required.
[0026] As shown in FIG. 4, positioned on the bottom of the module
compartment 10 are stops 13. Rotatably mounted to the bottom of the
module compartment on cylinder 14 is "L" shaped stop bracket 15.
Stop bracket 15 has a center opening to slide over cylinder 14.
Stop bracket 15 may be retained in place on cylinder 14 with a snap
ring or other suitable retaining device (such as the module mount
next described). The end of the stop bracket 15 includes a
projecting finger 15.1 that couples with finger 51. As shown, the
stops 13 are angled to accommodate the movement of the stop bracket
15 and provide stops to the bracket at a desired angle of bracket
movement or rotation. In use, the sensor connector 50 is first
threaded into the housing 1 and the stop bracket 15 next installed.
After installation of the stop bracket 15, the sensor connector 50
may rotate with respect to the housing 1 until finger 51 contacts
finger 15.1, further rotation of sensor connector (or relatively,
the housing) will rotate stop bracket 15 until bracket 15 contacts
stop 13. In this fashion, the housing is allowed to rotate with
respect to the sensor connector through a fixed angular range, here
through a range slightly greater than 360 degrees. Alternatively,
the interior wall of the port 22 may have a downwardly projecting
insertable finger (e.g. snap inserted in a corresponding groove)
that interfaces with a rotatable ring inserted into a
circumferential groove in the interior of the sensor connector--the
rotatable ring would have an upstanding finger that interfaces with
the port finger, providing almost 360 degrees of relative rotation
(not shown).
[0027] As described, the interaction of the sensor connector finger
51 with the bracket 15 and stops 13 creates a means to allow
rotation of the sensor connector within a fixed range, here the
range is slightly in excess of 360 degrees. The movable stop
bracket allows a minimum of one full 360 degree rotation. Other
means to allow rotation of the sensor connector with respect to the
housing, within a fixed range, may be employed. For instance the
sensor connector 50 may have a finger 50.3 projecting from the base
of the connector adjacent the housing exterior (shown dashed in
FIG. 3 detail). The exterior of the housing could have a slot into
which a downwardly projecting finger 50.2 may be inserted and fixed
(such as by a screw, or snap-in). This downwardly projecting finger
or stop bracket would be inserted after assembly, and act as a stop
to the upward projecting finger. In this fashion, the rotational
motion of the assembled sensor connector/housing may rotate through
a fixed range of about 360 degrees. The 360 degree rotation allows
for great flexibility in setting the orientation of the
housing/sensor for various mounting orientations, but no so great
to allow wiring, for instance between the sensor and housing, to
become tangled within the housing. Alternatively, a pivoting stop
bracket and with stops may be mounted on the exterior of the
housing and interface with a projecting finger such as finger 50.1
(the position of the finger and stop bracket may be interchanged),
however, this is not preferred as the pivoting bracket is exposed
to the external environment and may be damaged.
[0028] As shown in FIG. 4A, the inner sidewall of the compartment
10 contain detents or notches 55 located at various positions on
the sidewall. Their functionality will be described later.
Additionally inner sidewall has threads 54 to accommodate a cover.
Threads could be on the outer sidewall, or another means of
removably covering the opening into the compartment 10 could be
used.
[0029] Shown in FIGS. 5A & B is module holder 40. As shown,
holder 40 is an "U" shaped arm. Located on the bottom of the arm
are shown two inserts 42 (a single insert can be employed) to
retain an electrical plug, connector or socket, and a hollow
cylinder mount 43. Additionally, coaxial cable connectors can be
included in the arm. Module holder 40 is rotatably mounted in the
chamber 10 by sliding cylinder mount 43 onto cylinder 14, and may
be secured to cylinder via screw (threaded into cylinder 14), a
snap ring, or other retaining device. It is preferred that the
module holder 40 be raised from the floor of the compartment 10 to
accommodate wiring to be positioned between the rotatable module
holder 40 and the floor of the compartment 10, later described. For
this reason, the cylinder 14 may be a "stepped cylinder" such as
shown in detail 4C. Each upstanding arm of the "U" shaped module
holder 40 includes an outward facing finger or bump 44, located on
the arms at a height to fit into the notches 55 in the inner wall
of the compartment 10 (a single arm may be so equipped, but it is
preferred to use two arms, both so equipped). The arms are somewhat
flexible, allowing the notches 55 and projecting fingers act as a
"click stop" or detent mechanism to fix the location of the
rotatable module holder 40 with respect to the housing. The inward
facing surface of the upstanding arms contains a projecting finger
or bump 47, designed to interface a similarly positioned notch or
depression in the module to retain the module in the module holder
40 in a click-lock arrangement. Obviously, the bumps and notches
could be interchanged and accomplish the same result. Instead of
bumps on the inner walls of the module holder's arms, the top of
the module holder's arms may have inward projecting flanges
designed to retain a module, next described. An alternative design
is to have an outwardly projecting tab or ear at the top of each
arm of the U shaped module holder (or only on one arm) (not shown).
These tabs would ride on a ledge formed in the sidewall of the
module compartment. The click stop arrangement of bumps and notches
could be employed in the tab/ledge relationship, or alternatively,
the ledge may have cutouts sized to accommodate the tab portion, so
that as the tab rotates, it would fall into a corresponding cutout
to lock the position of the module holder in the module
compartment. All of these arrangements are considered a means to
engage the module holder with the module compartment. The module
holder may also comprise an "L" shaped holder, having only a single
upstanding arm.
[0030] Positioned onto module holder 40 is a electronic module 60
(see FIG. 6). As shown in FIGS. 6A and 6B, module includes a top
66, and a base, 67, and an electronics package that slides into the
cover (not show). Module 60 will contain the electrical components
to allow a user to interact with the sensor, and allow the sensor
to interact with the module. The particular module 60 shown is
designed to interface a level sensor, and contains a screen or
alpha numeric display to display the sensors return signal. For
this reason, module top 66 has a viewing window 61, and interface
buttons 62 to manually interact with the electronics in the module
60, and plugs 62.1 to allow a user to interact via another plug-in
instrument. Located on the bottom of the module (FIG. 6B) are one
or two electrical connectors or sockets 65 (such as a male adapter)
designed to interface a corresponding connector (such as a female
adapter) positioned in the insert 42 on the module holder 40. Two
connectors are preferred, one to connect the module 60 with the
sensor wiring, the other to connect the module 60 to the wiring
from the terminal compartment. When the module 60 is positioned in
the module holder 40, the module 40 will snap into place in the
holder 40, aligning the plugs or pins 65 in the module 60 with
plugs or pins positioned in the inserts 42 in the module holder 40.
Other arrangements of, or multiple connectors, may be used to fit
the particular needs of the level sensor. This includes separate
connectors for wireless antennas or a special communications link,
for example.
[0031] As shown in FIG. 6A, the module 60 has two lengthwise slots
69 to accommodate the arms of the module holder 40. Slots have
notches 69.1 to accommodate the fingers or bumps on the module
holder's arms. Also shown are two lengthwise channels 68. Sliding
in each of these channels is a module puller 90 (see FIG. 6C).
Module pullers 90 have a projecting stop 92 that will retain the
bar 90 in the channel 68, preventing upward removal of the bar.
Module pullers 90 are use to assist removal of a module 60
installed in the module holder 40, when positioned in the
compartment 10. To remove a module 60, the module pullers 90 are
slid upwardly until the stop 92 catches on the module cover 66.
Further upward force on the module pullers 90 will overcome the
click stop frictional arrangement between the module holder's arms
and compartment sidewalls, allowing removal of the module from the
module holder. The module pullers 90 provide a grasping surface,
and other mechanical means can be used, such as a grasp hook
pivotably mounted to the module holder case, finger grip ridges
molded in the module case, etc.
[0032] It is preferred that the fit between the module holder 40,
the module 60, and compartment 10 chamber be close, so that the
insertion of the module 60 into the holder 40 will force the
fingers or bumps 44 of the holder's arms into the notches 55 in the
compartment wall, thereby fixing the position of the interlocked
module 60 and module holder 40 with respect to the compartment 10.
Further rotation of the module/holder is thus prevented. In this
arrangement, the module holder, module and housing are locked into
a desired position, and any change of this relationship requires
removal of the module 60 from the holder 40.
[0033] FIG. 7 is a cross section through the housing showing the
relationship of the assembled parts. A cover 70 is then put over
the opening in the compartment 10, thus enclosing the components
therein. If an explosion proof arrangement is not needed, the cover
may simply be a retaining ring threaded or snapped onto or into the
top of the compartment 30 opening, thus allowing the user to view
and interact with the module.
[0034] The module holder as described is locked into a desired
orientation by the click stop or detent relationship between the
module holder 40 and inner sidewalls of the compartment 10. Other
mechanical means may be used to accomplish this task. For instance,
the module top 66 may have a ridges that snap into channels in the
sidewall of the compartment 10 (or vice versa) in an interlocking
arrangement, such as a dovetail-type joint. These channels in the
sidewall may be placed at various locations on the sidewall, for
instance, at 15 degree intervals, to permit the module to snap in
place at various orientations (0 degrees, 15 degrees, 30 degrees,
etc.). In this arrangement, the module holder 40 may be dispensed
with. A sufficient length wiring harness (attached to the module or
the compartment) may be employed to electrically connect the module
and compartment wiring, and allow the module to be removed form the
compartment before disconnecting the wiring. For instance, the
module may incorporate one or two plugs that connect with matching
plugs or blocks in the housing, with a sufficient length of cable
attached to the plugs to allow the module to be removed, and then
unplugged. Alternatively, each ridge in the module cover may
include a plug that snaps into place in a matching plug located in
the corresponding sidewall channel (each channel preferably having
such a plug to allow for different orientations of the module in
the compartment). Alternatively, the module may have a series of
pins positioned on the module bottom, where each pin is positioned
to touch one of a series of annular conductors mounted on a fixed
plate (e.g. a flat slip ring disk) in the compartment bottom (of
vice versa, e.g., the bottom of the module cover has positioned a
series of annular conductors, etc). Alternatively, other slip ring
or commentator arrangements may be employed between the module and
a module holder. The above embodiments provide the ability to
position the module at a selected orientations within the module
compartment. The cooperation of the module with module compartment,
or the module holder with the module compartment, provides a means
to fix the position of the module in the module compartment at a
select one of several positions. This "means" thus allow the user
to set and fix the position of the module in the module compartment
at a desired orientation.
[0035] Compartment 30 may be closed by a blank cover since this
compartment does not typically provide any display for the user.
For an explosion proof housing, it is preferred that cover for
compartment 10 include a glass window to provide a view port in the
cover 70. A preferred window cover is shown in cross section in
FIGS. 8A, B, and C. Cover 70 includes an annular ring 71, with an
opening therethrough. The ring is threaded, and has a top rim 75 to
retain a glass insert 72. Positioned between top rim surface and
glass 72 is an "O" ring 73. "O" ring 73 is retained in a circular
channel cut in the underside of the ring 71 top. The inside
sidewall of the ring 71 also has a grooves 78.1 into the side wall
to accommodate the flats 77.1 of the locking ring 77 (next
described). A channel(s) in the sidewall 76 enters the bottom
portion of the grooves. The channel 76 may be circumferential, or
each groove 78.1 will have an associated short channel 76 exiting
the bottom of the groove 78.1 to accommodate the flats 77.1 of the
locking ring in a locked position.
[0036] Locking ring 77 may be similar to an open snap ring, or be a
closed circular ring 77. The locking ring 77 depicted in FIG. 8B is
a closed ring and includes projecting flats 77.1, and cutouts 77.2.
To install, the locking ring flats 77.1 are aligned with the
corresponding grooves 78.1, the locking ring 77 is slid down the
interior sidewall 78 of the outer ring 70 until the locking ring is
even with channel 76, and then the locking ring is rotated, placing
the ring flats 77.1 in the channel 76 or short channels 76, thereby
by retaining the locking ring 77 in ring 71. The locking ring's
outer diameter is smaller then the inner diameter of the ring 71,
leaving a gap 79 between the locking ring 77 and inner sidewall 78
of the ring 71. After the cover 70 is assembled, epoxy 80 may be
easily inserted (such as by a syringe though this gap 79) between
the glass 72, the inner sidewall 78, and the top rim 75. This
epoxied fit is needed to comply with standards set by the
International Electrotechnical Commission (IEC) for explosion proof
standards, particularly IEC 60079-1, hereby incorporated by
reference. The cutouts 77.2 are used to manipulate an installed
ring. Projecting flats 77.1 may be inclined at a slight angle with
respect to the locking ring 77 to help retain an installed ring in
the channel.
[0037] The cover may have internal threads or external threads to
intermate with suitably positioned threads on the housing. The
threadable join is needed for explosion proof housings, but other
means of attaching a cover, know to those of skill in the art, may
be used in a non-explosion proof embodiment. The locking ring shown
is a completely closed ring, however, the locking ring may be a
snap ring with projecting flats. If a snap ring is used as a
locking ring, the grooves 78.1 in the sidewall may be dispensed
with, as the locking ring can be compressed to allow the projecting
flats 77.1 to clear the sidewall 78 when installing. Alternatively,
the channel 76 may be dispensed with and the grooves 78.1 retained,
in which event the snap ring should have sufficient expansive
force, when installed, to force the flats in a tight relationship
in the grooves 76 to retain the snap ring.
[0038] Another embodiment includes a two piece snap ring comprising
two co-planar inner and outer rings, offset from each other by a
gap, and joined together at discrete intervals. The outer ring is
sized to be insertable into the channel 76 in the sidewall 78 of
the cover, and the inner ring is sufficiently offset from the outer
ring so that the gap between the inner/outer rings is adjacent the
sidewall of the cover, thereby providing the needed space for
injection of epoxy adjacent the glass. With this dual ring
embodiment, the projecting flanges are not needed. The interior of
the terminal compartment 30 is detailed in FIG. 9. Two ports 23
allow access to the interior of this compartment, while channel 21
allows wiring to be passed from this compartment to the module
compartment. As shown, this compartment has a raised flat flange
32, on which a semicircular terminal block, circuit board or wafer
board may be attached. Wiring (such as for power and
communications) is brought into the terminal compartment through
ports 23 (generally through a single port). One of the ports may be
used for a mounting an antenna to allow for wireless
communications. Wiring from the board (or from the outside through
port 23) travels into the module compartment via port 21 to provide
power/communications to the electronic module in the module
compartment. Generally, once the wiring is in place between the two
compartments, the port 21 will be filled with sealant or epoxy to
environmentally isolate the two compartments. In a single
compartment design, (i.e. no terminal compartment), wiring (such as
power) would be brought directly into the module compartment,
either through port 22, of via a port positioned as needed into the
module compartment.
[0039] Because the module may rotate slightly over 360 degrees, it
is necessary to accommodate the internal wiring in the module
compartment 20 to allow for rotation of the module. Shown in FIG.
10 is the module compartment 10, with center cylinder 14. The
module holder 44 is shown dashed. Also shown are the inserts 42 on
the module holder into which the electrical connectors are
positioned. The wiring 100 connects to the electrical connectors in
the inserts 42. Wiring 100 is preferably a ribbon type cable with
sufficient length within the chamber to accommodate the movement of
the electrical connector in the links 42. A round cable or cable
bundle may also be employed, and posts in the floor of the module
compartment may be used to guide cable movement. For an explosion
proof housing, the cover 70 should include the sealing features
disclosed the provisional application entitled "Explosion Proof
Housing Cover Seal" application No. 61/122,958 filed on Dec. 16,
2008 (hereby incorporated by reference).
* * * * *