Abstrict An ultrasonic gas meter housing member is configured to provide
an associated multi-configuration ultrasonic gas meter assembly.
The housing member is installable in an ultrasonic gas flow meter
which includes an internal flow measurement tube along which gas
travels for flow measurement, the tube having an inlet end and an
outlet end. The ultrasonic gas meter housing member includes a closed
back portion and a front portion spaced from the back portion to
define a space for receiving the internal flow measurement tube
such that the tube extends across the internal space of the housing
member. At least one wall portion extends between the back portion
and the front portion, the wall portion having a first opening and
a second opening therethrough for connection of the housing member
to a gas inlet pipe and a gas outlet pipe. The gas meter housing
member is symmetrical about a plane which divides the housing member
into a first portion and a second portion. The symmetrical configuration
enables the housing member to receive the flow measurement tube
in both a first orientation in which the first and second opening
face in a first direction and the inlet end of the flow measurement
tube is positioned in the first portion of the housing member and
the outlet end is positioned in the second portion, and a second
orientation in which the first and second opening face in a second
direction substantially perpendicular to the first direction and
the inlet end of the flow measurement tube is positioned in the
second portion of the gas meter housing member and the outlet end
is positioned in the first portion. The first and second orientations
are particularly useful in enabling the housing member to be used
both in gas meter installation sites where the gas pipes extend
downward and in gas meter installation sites where the gas pipes
extend upward.
Claims What is claimed is:
1. A multi-configuration ultrasonic gas meter assembly having at
least first and second assembly configurations, comprising: a first
housing member including a back enclosure portion, a front portion
spaced from the back enclosure portion to define an internal space,
and wall portions extending between the back enclosure portion and
the front portion, one of the wall portions having a first opening
and a second opening therethrough for connection to a gas inlet
pipe and a gas outlet pipe; a flow tube assembly including a gas
flow measurement tube for positioning at least partially within
the internal space of the first housing member and having a gas
inlet end and a gas outlet end; at least one ultrasonic transducer
positioned proximate the gas flow measurement tube for directing
an ultrasonic signal along at least a portion of a length of the
gas flow measurement tube; and wherein the first assembly configuration
includes the gas flow measurement tube positioned within the internal
space of the first housing member such that the first and second
openings each face in a same first direction and gas travels in
the first opening, through the gas flow measurement tube from the
gas inlet end to the gas outlet end, and out of the second opening,
and the second assembly configuration includes the gas flow measurement
tube positioned within the internal space of the first housing member
such that the first and second openings each face in a same second
direction which is substantially opposite the first direction and
in which gas travels in the second opening, through the gas flow
measurement tube from the gas inlet end to the gas outlet end, and
out of the first opening.
2. The multi-configuration ultrasonic gas meter assembly of claim
1 wherein the first housing member includes a first plurality of
attachment apertures and the flow tube assembly includes a second
plurality of attachment apertures, the flow tube assembly being
attached to the first housing member by alignment of the first plurality
of attachment apertures with the second plurality of attachment
apertures, the first plurality of attachment apertures aligning
with the second plurality of attachment apertures in both the first
assembly configuration and the second assembly configuration.
3. The multi-configuration ultrasonic gas meter assembly of claim
1 wherein the flow tube assembly further includes a plate member
on which the second plurality of attachment apertures are located,
the gas flow measurement tube being attached to the plate member.
4. The multi-configuration ultrasonic gas meter assembly of claim
3 further comprising openings in the plate member, and wherein
the at least one ultrasonic transducer comprises a first transducer
positioned toward the inlet end of the gas flow measurement tube
and a second transducer positioned toward the outlet end of the
gas flow measurement tube, the first and second transducers extending
through respective ones of the openings in the plate member.
5. The multi-configuration ultrasonic gas meter assembly of claim
3 further comprising: a second housing member including a third
plurality of attachment apertures; extensions on the plate member
with a fourth plurality of attachment apertures, wherein the third
plurality of attachment apertures are positioned for alignment with
the fourth plurality of attachment apertures for attachment of the
second housing member to the plate member.
6. The multi-configuration ultrasonic gas meter assembly of claim
1 further comprising a divider plate extending across the internal
space of the first housing member and dividing the housing into
first and second portions, the divider plate including an externally
facing edge with at least one recessed portion for receiving the
gas flow measurement tube.
7. The multi-configuration ultrasonic gas meter assembly of claim
6 further comprising a first plurality of attachment apertures positioned
on the first portion of the first housing member and a second plurality
of attachment apertures positioned on the second portion of the
first housing member, wherein the second plurality of attachment
apertures are symmetrically oriented relative to the first plurality
of attachment apertures about a plane defined by the divider plate.
8. The multi-configuration ultrasonic gas meter assembly of claim
1 wherein the first direction is a substantially downward direction
such that at least one of the first and second openings of the first
housing member permits drainage of fluid from the first housing
member in the first assembly configuration.
9. A multi-configuration ultrasonic gas meter assembly, comprising:
a first housing member including a back enclosure portion, a front
portion spaced from the back enclosure portion to define an internal
space, and wall portions extending between the back enclosure portion
and the front portion, one of the wall portions having a first opening
and a second opening therethrough for connection to a gas inlet
pipe and a gas outlet pipe; a gas flow measurement tube for positioning
at least partially within the internal space of the first housing
member and having a gas inlet end and a gas outlet end; at least
one ultrasonic transducer positioned proximate the gas flow measurement
tube for directing an ultrasonic signal along at least a portion
of a length of the gas flow measurement tube; and a divider plate
defining a plane and extending across the internal space of the
first housing member and dividing the internal space into first
and second portions having perimeter shapes, the perimeter shape
of the first portion of the internal space comprising a mirror-image
of the perimeter shape of the second portion of the internal space
about the plane defined by the divider plate.
10. The multi-configuration ultrasonic gas meter assembly of claim
9 wherein the divider plate includes an externally facing edge
portion having at least one recess for receiving a portion of the
gas flow measurement tube.
11. An ultrasonic gas meter assembly for installation in both gas
meter systems in which a gas inlet pipe and a gas outlet pipe extend
substantially downward and gas meter systems in which the gas inlet
pipe and gas outlet pipe extend substantially upward, the gas meter
assembly comprising: a first housing member including a back enclosure
portion and wall portions extending from the back enclosure portion
and defining an internal space thereof, one of the wall portions
including a first opening therethrough and a second opening therethrough
for connecting the first housing member to the gas inlet pipe and
gas outlet pipe, a divider plate extending across the internal space
and dividing the internal space into first and second portions;
a gas flow measurement tube for positioning at least partially within
the internal space of the first housing member and having a gas
inlet end and a gas outlet end; at least one ultrasonic transducer
positioned proximate the gas flow measurement tube for directing
an ultrasonic signal along at least a portion of a length of the
gas flow measurement tube; and means for attaching the first housing
member to the gas flow measurement tube in a first orientation in
which the inlet end is positioned in the first portion of the internal
space and the outlet end is positioned in the second portion of
the internal space, and for attaching the first housing member to
the gas flow measurement tube in a second orientation in which the
inlet end is positioned in the second portion of the internal space
and the outlet end is positioned in the first portion of the internal
space.
12. The ultrasonic gas meter assembly of claim 11 wherein the divider
plate includes an externally facing edge portion having at least
one recess for receiving a portion of the gas flow measurement tube.
13. An ultrasonic gas meter housing member installable in an ultrasonic
gas flow meter which includes an internal flow measurement tube
along which gas travels for flow measurement, the tube having an
inlet end and an outlet end, the ultrasonic gas meter housing member
comprising: a back panel portion; a front portion spaced from the
back panel portion to define a space for receiving the internal
flow measurement tube; wall portions extending between the back
panel portion and the front portion, at least one of the wall portions
having a first opening and a second opening therethrough for connection
to a gas inlet pipe and a gas outlet pipe; and wherein the gas meter
housing member is configured to receive the internal flow measurement
tube when oriented in at least two different positions relative
thereto, including a first position in which the first and second
openings face in a first direction and gas travels in the first
opening, through the internal flow measurement tube from the inlet
end to the outlet end, and out of the second opening, and a second
position in which said first and second openings face in a second
direction which is substantially opposite the first direction and
in which gas travels in the second opening, through the internal
flow measurement tube from the inlet end to the outlet end, and
out of the second opening.
14. An ultrasonic gas meter housing member installable in an ultrasonic
gas flow meter which includes an internal flow measurement tube
along which gas travels for flow measurement, the tube having an
inlet end and an outlet end, the ultrasonic gas meter housing member
comprising: a closed back portion; a front portion spaced from the
back portion to define a space for receiving the internal flow measurement
tube such that the tube extends substantially along at least a portion
of a longitudinal axis of the housing member; first, second, third,
and fourth wall portions extending between the back portion and
the front portion, the first wall portion having a first opening
and a second opening therethrough for connection of the housing
member to a gas inlet pipe and a gas outlet pipe, the first and
second openings facing in substantially the same direction; and
wherein the gas meter housing member is symmetrical about a plane
which divides the gas meter housing member into a first half and
a second half, the plane being perpendicular to the longitudinal
axis, such symmetrical configuration for receiving the flow measurement
tube in both a first orientation in which the first and second opening
face in a first direction and the inlet end of the flow measurement
tube is positioned in the first half of the gas meter housing member
and the outlet end is positioned in the second half of the gas meter
housing member, and a second orientation in which the first and
second opening face in a second direction substantially perpendicular
to the first direction and the inlet end of the flow measurement
tube is positioned in the second half of the gas meter housing member
and the outlet end is positioned in the first half of the gas meter
housing member.
15. The ultrasonic gas meter housing member of claim 14 further
comprising a divider plate which defines said plane and extends
across the internal space of the housing member, the divider plate
including an outwardly facing edge having at least one recessed
portion shaped to receive a flow measurement tube.
16. An ultrasonic gas meter housing member installable in an ultrasonic
gas flow meter which includes an internal flow measurement tube
along which gas travels for flow measurement, the tube having an
inlet end and an outlet end, the ultrasonic gas meter housing member
comprising: a closed back portion; an open front portion spaced
from the back portion to define a space for receiving the flow measurement
tube such that the tube extends substantially along at least a portion
of a longitudinal axis of the housing member; at least one wall
portion extending between the closed back portion and the open front
portion and having a first connection opening and a second connection
opening therethrough, one of the first and second connection openings
for taking in gas and the other of said connection openings for
exhausting gas, the first and second openings facing in substantially
the same direction; a divider plate defining a plane and extending
across the internal space of the housing member and dividing the
space into first and second portions; and a plurality of attachment
apertures on the front portion for connecting the flow measurement
assembly to the front portion, including a first plurality of attachment
apertures positioned to a first side of the divider plate and a
second plurality of apertures positioned to a second side of the
divider plate, an orientation of the second plurality of attachment
apertures being symmetrical relative to the first plurality of attachment
apertures about the plane defined by the divider plate.
Description FIELD OF THE INVENTION
The present invention relates to ultrasonic gas flow meters and,
more particularly, to an ultrasonic gas flow meter housing which
facilitates interconnection with other gas flow meter components
to provide a multi-configuration system.
BACKGROUND OF THE INVENTION
Ultrasonic gas flow meters are generally well known. Such meters
commonly utilize a technique in which the difference between the
time of travel of an ultrasonic wave upstream in a flowing gas and
the time of travel of an ultrasonic wave downstream in the flowing
gas is used to determined the flow rate of the gas. However, other
techniques are also known and used.
Accumulation of liquids in the housings of ultrasonic gas flow
meters can occur with sufficient frequency and in sufficient quantity
to interfere with accurate gas flow measurement. In such instances
the excessive liquid presents a service and maintenance problem
for the gas utilities which maintain such meters, and therefore
acts as a potential deterrent to successful widespread introduction
and use of ultrasonic gas flow meters. The standard attachment position
for residential size gas meters is with the inlet and outlet piping
connections positioned on the top of the meter case or housing.
In this position, the meter housing can become an accumulator for
any liquids that are being transported by the flowing gas. In such
ultrasonic gas flow meters if the liquid enters the area through
which ultrasonic signals pass, the gas flow volume will tend to
be measured inaccurately.
Thus, in certain applications there is a need for positioning the
inlet and outlet piping connections on the bottom of the meter housing
in order to permit the connections to effectively act as drains
for any liquids that may enter the meter. However, this housing
configuration presents a problem in many areas where the majority
of gas meter installation sites still include downwardly extending
inlet and outlet piping positioned for entry into the top of a gas
meter housing. Utilizing two different gas meter housing configurations,
one with top openings and one with bottom openings, would increase
manufacturing costs and would be less well received by the gas utilities.
Accordingly, it would be desirable to provide a gas meter housing
configured to reduce liquid accumulation therein when installed.
It would also be desirable to provide a gas meter housing adapted
for installation in at least two different positions within ultrasonic
gas meter systems, thereby providing a single housing useful in
multiple installation schemes.
SUMMARY OF THE INVENTION
The present invention is an ultrasonic gas meter housing member
configured to provide an associated multi-configuration ultrasonic
gas meter assembly. In a preferred embodiment of the invention the
housing member is installable in an ultrasonic gas flow meter which
includes an internal flow measurement tube along which gas travels
for flow measurement, the tube having an inlet end and an outlet
end. The ultrasonic gas meter housing member includes a closed back
portion generally rectangular in shape and a front portion spaced
from the back portion to define a space for receiving the internal
flow measurement tube such that the tube extends substantially along
at least a portion of a longitudinal axis of the housing member.
First, second, third, and fourth wall portions extending between
the back portion and the front portion, the first wall portion having
a first opening and a second opening therethrough for connection
of the housing member to a gas inlet pipe and a gas outlet pipe,
the first and second openings facing in substantially the same direction.
The gas meter housing member is symmetrical about a plane which
divides the housing member into a first half and a second half,
the plane being perpendicular to the longitudinal axis. The symmetrical
configuration enables the housing member to receive the flow measurement
tube in both a first orientation in which the first and second opening
face in a first direction and the inlet end of the flow measurement
tube is positioned in the first half of the housing member and the
outlet end is positioned in the second half, and a second orientation
in which the first and second opening face in a second direction
substantially opposite to the first direction and the inlet end
of the flow measurement tube is positioned in the second half of
the gas meter housing member and the outlet end is positioned in
the first half. The first and second orientations are particularly
useful in enabling the housing member to be used both in gas meter
installation sites where the gas pipes extend downward and in gas
meter installation sites where the gas pipes extend upward, so that
two different housing configurations need not be provided. Further,
in installations where the gas pipes extend upward, the first and
second openings through the housing member will face downward and
will prevent the build up of liquids within the meter by allowing
them to drain.
In another aspect of the invention, a multi-configuration ultrasonic
gas meter assembly is provided and includes a first housing member
having a back enclosure portion, a front portion spaced from the
back enclosure portion to define an internal space, and at least
one wall portion extending between the back enclosure portion and
the front portion, at least one wall portion having a first opening
and a second opening therethrough for connection to a gas inlet
pipe and a gas outlet pipe. A gas flow measurement tube is provided
for positioning at least partially within the internal space of
the first housing member and has a gas inlet end and a gas outlet
end. At least one ultrasonic transducer is positioned proximate
the gas flow measurement tube for directing an ultrasonic signal
along at least a portion of a length of the gas flow measurement
tube. An orientation between the first housing member and the measurement
tube is selectable between at lest two configurations as necessary
for attachment of the gas inlet pipe and the gas outlet pipe, and
includes a first assembly configuration in which the first and second
openings face in a first direction and gas travels in the first
opening, through the gas flow measurement tube from the inlet end
to the outlet end, and out of the second opening, and a second assembly
configuration in which the first and second openings face in a second
direction which is substantially opposite the first direction and
in which gas travels in the second opening, through the gas flow
measurement tube from the inlet end to the outlet end, and out of
the first opening. As above, the two assembly configurations facilitate
installation of the gas meter assembly both in gas meter installation
sites where the gas pipes extend downward and in gas meter installation
sites where the gas pipes extend upward.
Accordingly, it is an object of the present invention to provide
an ultrasonic gas meter housing member configured for attachment
to both downwardly extending gas pipes and upwardly extending gas
pipes; a multi-configuration ultrasonic gas meter assembly; an ultrasonic
gas meter housing positionable to permit drainage of fluid therefrom;
and a method of manufacturing an improved ultrasonic gas meter housing
member. Other objects and advantages of the present invention may
be ascertained from a review of the following description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B show front perspective views of an ultrasonic gas
meter housing member in accordance with one embodiment of the present
invention;
FIG. 2 shows an exploded view of a multi-configuration ultrasonic
gas meter assembly incorporating the housing member of FIGS. 1A
and 1B in a first assembly configuration; and
FIG. 3 shows an exploded view of the multi-configuration ultrasonic
gas meter assembly of FIG. 2 in a second assembly configuration.
DETAILED DESCRIPTION
Referring to the drawings, FIGS. 1A and 1B show front perspective
views of an ultrasonic gas meter housing member 10 according to
a preferred embodiment of the invention, FIG. 1A showing gas pipe
connection openings 12 and 14 of the housing member 10 facing in
a generally upward direction and FIG. 1B showing openings 12 and
14 facing in a generally downward direction. Three reference planes
A, B, and C are shown in shadow with plane A extending generally
parallel to a front portion 16 of the housing member 10 plane B
extending vertically across a central portion of the housing member
10 and plane C extending horizontally across a central portion
of the housing member 10. As shown, housing member is symmetrical
about plane B and partially symmetrical about plane C. With this
symmetry about the central planes, the internal features of the
housing member are the same, relative to the remaining meter components,
whether the body is oriented with the connection openings 12 and
14 facing upward or downward. Such remaining meter components are
shown in the exploded views of FIGS. 2 and 3 and generally include
a flow tube assembly 18 one or more ultrasonic transducers 20
and a front housing member 22. The flow tube assembly 18 includes
a gas flow measurement tube 24 having an inlet end 26 and an outlet
end 28 along which gas travels for flow measurement.
Referring again to FIGS. 1A and 1B, the housing member 10 includes
a closed back portion 30 which, in the preferred embodiment, is
generally rectangular in shape. The front portion 16 being spaced
from the back portion 30 defines an internal space 32 for receiving
the gas flow measurement tube such that the tube extends substantially
along at least a portion of a longitudinal or horizontal axis of
the housing member, which axis extends within plane C. First, second,
third and fourth wall portions 34 36 38 and 40 extend between
the back portion 30 and the front portion 16 of the housing member.
The first wall portion includes opening 12 and opening 14 therethrough
for connection of the housing member to a gas inlet pipe and a gas
outlet pipe. The openings 12 and 14 preferably face in substantially
the same direction as shown.
As noted above, the housing member 10 is symmetrical about plane
B which divides the housing member into a first portion 42 and a
second portion 44. Such symmetrical configuration enables the housing
member 10 to receive the flow measurement tube in both a first orientation
in which the openings 12 and 14 face upward and the inlet end 26
of the flow measurement tube 24 is positioned in portion 42 of the
housing member and the outlet end 28 is positioned in portion 44
of the housing member 10 and a second orientation in which the
openings 12 and 14 face generally downward and the inlet end 26
of the gas flow measurement tube 24 is positioned in portion 44
of the gas meter housing member and the outlet end 28 is positioned
in portion 42. The housing member 10 also includes a divider plate
46 which extends across internal space 32 in alignment with and
defining plane B. The divider plate 46 includes an outwardly facing
edge 48 having at least one recessed portion 50 shaped to receive
a portion of the flow measurement tube 24. Preferably, an internal
perimeter shape of portion 42 and an internal perimeter shape of
portion 44 are the same such that the perimeter shapes are mirror
images of each other about plane B. This similarity of internal
configuration facilitates receipt of the remaining gas meter assembly
components within either portion as necessary.
Front portion 16 also includes a plurality of attachment apertures
52A and 52B arranged thereabout for connecting the gas flow measurement
tube assembly thereto. Attachment apertures 52A are positioned to
a first side of the divider plate 46 on portion 42 of the housing
member 10 and attachment apertures 52B are positioned to a second
side of the divider plate 46 on portion 44 of the housing member
10. Notably, the symmetrical nature of the housing member extends
to the positioning of the apertures 52A and 52B about plane B of
the housing member 10. As will be explained in greater detail below,
the symmetry of the positioning of such attachment apertures 52A
and 52B facilitates attachment of the housing member 10 to the remaining
components of the ultrasonic gas meter assemblies in an orientation
in which openings 12 and 14 extend upward and an orientation in
which openings 12 and 14 extend downward.
Referring to FIG. 2 one configuration for an ultrasonic gas meter
assembly incorporating the housing member 10 is shown in which the
housing member 10 is positioned with openings 12 and 14 facing substantially
upward for connection to downwardly extending gas inlet pipe 54
and gas outlet pipe 56. Any known gas pipe connection arrangement
can be used with the present invention. The flow tube assembly 18
includes gas flow measurement tube 24 and a connection plate 58
to which the gas flow measurement tube 24 is attached by fasteners
60. Thus, the gas flow measurement tube 24 secures to plate 58 and
the plate 58 is then secured to the housing member 10. In this regard,
plate 58 is provided with a plurality of apertures 61 for attaching
the flow tube assembly to the housing member 10 via alignment with
the attachment apertures 52A and 52B thereof. The mounting apertures
61 align with the attachment apertures 52A and 52B. Fasteners 62
are then inserted within the aligned apertures. Importantly, the
apertures 61 of plate 58 align with apertures 52A and 52B of housing
member 10 both when the housing member 10 is positioned with openings
12 and 14 extending upward as shown in FIG. 2 and when the housing
member 10 is positioned with openings 12 and 14 extending downward
as shown in FIG. 3. In this regard, FIG. 3 shows a second configuration
for the assembly. The recessed portion 50 of divider plate 46 is
shaped and configured to receive a central portion of the gas flow
measurement tube 24 when the flow tube assembly 18 is attached to
the housing member 10.
Also shown in FIGS. 2 and 3 are transducers 20 which extend through
openings 64 in the plate 58 so that they are positioned proximate
the gas flow measurement tube 24 to direct ultrasonic signals along
the length of the tube for gas flow measurement purposes. A battery
66 is provided for powering the transducers 20 and their associated
electronics which are included on circuit board 68. In a preferred
embodiment, the transducers 20 include a first transducer positioned
toward the inlet end 26 of the gas flow measurement tube 24 and
a second transducer positioned toward the outlet end 28 of the gas
flow measurement tube 24. A third transducer may also be provided
as is known in the art for speed of sound measurement. Front housing
member 22 also includes a plurality of attachment apertures 70 which
are positioned for alignment with a corresponding plurality of attachment
apertures 72 which are also positioned on plate 58 particularly
on projections 74 which extend from plate 58.
In the first assembly configuration shown in FIG. 2 when assembled
the gas flow measurement tube 24 is positioned with inlet end 26
within portion 42 of the housing member 10 and with outlet end 28
positioned in portion 44 of the housing member 10. During operation
in this configuration gas flows in inlet pipe 54 through opening
12 into inlet end 26 of gas flow measurement tube 24 and along
the length thereof to outlet end 28 out of opening 14 and into
gas outlet pipe 56. In the second assembly configuration shown in
FIG. 3 the gas flow measurement tube 24 is positioned with inlet
end 26 within portion 44 of housing member 10 and with outlet end
28 within portion 42 of housing member 10. In this configuration,
during operation gas flows in gas inlet pipe 54 through opening
14 of housing member 10 into gas inlet end 26 of gas flow measurement
tube 24 and along the length thereof to outlet end 28 through opening
12 of housing member 10 and into gas outlet pipe 56. In both configurations,
the components of the gas meter assembly, other than the housing
member 10 remain in a single configuration which is adapted for
flow measurement from left to right relative to the front of the
assembly. The housing member 10 is simply rotated 180 degrees as
necessary to attach to either downwardly extending pipes 54 and
56 of FIG. 2 or upwardly extending pipes 54 and 56 of FIG. 3. Thus,
the housing member 10 and its manner of connection to the remaining
components of the system facilitates a multi-configuration gas meter
assembly which can be used in both types of installations. This
multi-configuration assembly therefore eliminates the need for manufacturing
two different gas meter assemblies and the related cost which would
be associated therewith.
Housing members 10 and 22 and plate 58 may be formed from any
suitable material such as a molded plastic, or other materials commonly
used in the art.
While the forms of the apparatus herein described constitute preferred
embodiments of the invention, it is to be understood that the invention
is not limited to these precise forms of apparatus, and changes
may be made therein without departing from the scope of the invention.
For example, slight differences between the internal perimeter
shape of portions 42 and 44 of the housing member 10 could exist
where such differences do not interfere with connection to the remaining
components of the ultrasonic gas meter assembly. Further, while
attachment apertures are provided on both housing member 10 and
plate 58 for alignment in both assembly configurations, it is recognized
that housing member 10 could instead be provided with similarly
positioned threaded extensions which would pass through the attachment
apertures of plate 58 with nut-type members then being threaded
onto the threaded extensions. Still further, while a generally rectangular
shaped housing is shown in the preferred embodiment, it is contemplated
that other housing shapes could be provided without departing from
the scope of the invention. |