U.S. patent application number 15/632005 was filed with the patent office on 2018-09-13 for pressure sensor having coplanar meter body with sensor overpressure protection.
The applicant listed for this patent is Honeywell International Inc.. Invention is credited to Ronald E. Beselt, Richard D. Daugert, George Hershey.
Application Number | 20180259413 15/632005 |
Document ID | / |
Family ID | 63444447 |
Filed Date | 2018-09-13 |
United States Patent
Application |
20180259413 |
Kind Code |
A1 |
Hershey; George ; et
al. |
September 13, 2018 |
PRESSURE SENSOR HAVING COPLANAR METER BODY WITH SENSOR OVERPRESSURE
PROTECTION
Abstract
An apparatus includes a sensor body and a sensor configured to
measure differential pressure. The apparatus also includes first
and second coplanar pressure inputs in or on the sensor body, where
the pressure inputs are configured to provide multiple input
pressures to the sensor. Each pressure input includes a barrier
diaphragm configured to move in response to pressure and an
overload diaphragm configured to limit movement of the barrier
diaphragm. First and second fill fluid may be configured to convey
the pressures from the barrier diaphragms of the pressure inputs to
the sensor as first and second input pressures. Passages may be
configured to transport the fill fluid between (i) gaps between the
barrier diaphragms and the overload diaphragms of the pressure
inputs and (ii) the sensor and gaps between the overload diaphragms
and the sensor body.
Inventors: |
Hershey; George; (Blue Bell,
PA) ; Beselt; Ronald E.; (Burnaby, CA) ;
Daugert; Richard D.; (Doylestown, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Honeywell International Inc. |
Morris Plains |
NJ |
US |
|
|
Family ID: |
63444447 |
Appl. No.: |
15/632005 |
Filed: |
June 23, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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62469716 |
Mar 10, 2017 |
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62469954 |
Mar 10, 2017 |
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62470080 |
Mar 10, 2017 |
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62470089 |
Mar 10, 2017 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01L 7/082 20130101;
G01L 19/14 20130101; G01L 19/0618 20130101; G01L 13/026 20130101;
G01L 15/00 20130101; G01L 19/0645 20130101; G01L 19/0663 20130101;
G01L 7/08 20130101; G01L 11/004 20130101 |
International
Class: |
G01L 19/06 20060101
G01L019/06; G01L 13/02 20060101 G01L013/02; G01L 7/08 20060101
G01L007/08 |
Claims
1. An apparatus comprising: a sensor body; a sensor configured to
measure differential pressure; and first and second coplanar
pressure inputs in or on the sensor body, the pressure inputs
configured to provide multiple input pressures to the sensor, each
pressure input comprising: a barrier diaphragm configured to move
in response to pressure; and an overload diaphragm configured to
limit movement of the barrier diaphragm.
2. The apparatus of claim 1, further comprising: a first fill fluid
configured to convey the pressure from the barrier diaphragm of the
first pressure input to the sensor as a first input pressure; and a
second fill fluid configured to convey the pressure from the
barrier diaphragm of the second pressure input to the sensor as a
second input pressure.
3. The apparatus of claim 2, further comprising: at least one first
passage configured to transport the first fill fluid between (i) a
gap between the barrier diaphragm of the first pressure input and
the overload diaphragm of the first pressure input and (ii) the
sensor and a gap between the overload diaphragm of the second
pressure input and the sensor body; and at least one second passage
configured to transport the second fill fluid between (i) a gap
between the barrier diaphragm of the second pressure input and the
overload diaphragm of the second pressure input and (ii) the sensor
and a gap between the overload diaphragm of the first pressure
input and the sensor body.
4. The apparatus of claim 1, wherein the barrier diaphragm and the
overload diaphragm of each pressure input are welded to the sensor
body.
5. The apparatus of claim 1, wherein each pressure input further
comprises: a seal located along a periphery of the barrier
diaphragm and a periphery of the overload diaphragm of that
pressure input.
6. The apparatus of claim 1, wherein the barrier diaphragm of each
pressure input is configured to nest with the overload diaphragm of
that pressure input.
7. The apparatus of claim 1, wherein the sensor comprises one of
multiple sensors.
8. A system comprising: a manifold; and a pressure sensor mounted
to the manifold, the pressure sensor comprising: a sensor body; a
sensor configured to measure differential pressure; and first and
second coplanar pressure inputs in or on the sensor body, the
pressure inputs configured to provide multiple input pressures to
the sensor, each pressure input comprising: a barrier diaphragm
configured to move in response to pressure; and an overload
diaphragm configured to limit movement of the barrier
diaphragm.
9. The system of claim 8, wherein the pressure sensor further
comprises: a first fill fluid configured to convey the pressure
from the barrier diaphragm of the first pressure input to the
sensor as a first input pressure; and a second fill fluid
configured to convey the pressure from the barrier diaphragm of the
second pressure input to the sensor as a second input pressure.
10. The system of claim 9, wherein the pressure sensor further
comprises: at least one first passage configured to transport the
first fill fluid between (i) a gap between the barrier diaphragm of
the first pressure input and the overload diaphragm of the first
pressure input and (ii) the sensor and a gap between the overload
diaphragm of the second pressure input and the sensor body; and at
least one second passage configured to transport the second fill
fluid between (i) a gap between the barrier diaphragm of the second
pressure input and the overload diaphragm of the second pressure
input and (ii) the sensor and a gap between the overload diaphragm
of the first pressure input and the sensor body.
11. The system of claim 8, wherein the barrier diaphragm and the
overload diaphragm of each pressure input are welded to the sensor
body.
12. The system of claim 8, wherein each pressure input further
comprises: a seal located along a periphery of the barrier
diaphragm and a periphery of the overload diaphragm of that
pressure input.
13. The system of claim 8, wherein the barrier diaphragm of each
pressure input is configured to nest with the overload diaphragm of
that pressure input.
14. The system of claim 8, wherein the sensor comprises one of
multiple sensors.
15. A method comprising: conveying multiple input pressures to a
sensor; and measuring a differential pressure using the sensor;
wherein the multiple input pressures are conveyed using first and
second coplanar pressure inputs in or on a sensor body; and wherein
each pressure input comprises: a barrier diaphragm configured to
move in response to pressure; and an overload diaphragm configured
to limit movement of the barrier diaphragm.
16. The method of claim 15, further comprising: conveying, using a
first fill fluid, the pressure from the barrier diaphragm of the
first pressure input to the sensor as a first input pressure; and
conveying, using a second fill fluid, the pressure from the barrier
diaphragm of the second pressure input to the sensor as a second
input pressure.
17. The method of claim 16, further comprising: transporting,
through at least one first passage, the first fill fluid between
(i) a gap between the barrier diaphragm of the first pressure input
and the overload diaphragm of the first pressure input and (ii) the
sensor and a gap between the overload diaphragm of the second
pressure input and the sensor body; and transporting, through at
least one second passage, the second fill fluid between (i) a gap
between the barrier diaphragm of the second pressure input and the
overload diaphragm of the second pressure input and (ii) the sensor
and a gap between the overload diaphragm of the first pressure
input and the sensor body.
18. The method of claim 15, wherein the barrier diaphragm and the
overload diaphragm of each pressure input are welded to the sensor
body.
19. The method of claim 15, wherein each pressure input further
comprises: a seal located along a periphery of the barrier
diaphragm and a periphery of the overload diaphragm of that
pressure input.
20. The method of claim 15, wherein the barrier diaphragm of each
pressure input nests with the overload diaphragm of that pressure
input during an overpressure condition on that barrier diaphragm.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY CLAIM
[0001] This application claims priority under 35 U.S.C. .sctn.
119(e) to the following U.S. provisional patent applications:
[0002] U.S. Provisional Patent Application No. 62/469,716 filed on
Mar. 10, 2017;
[0003] U.S. Provisional Patent Application No. 62/469,954 filed on
Mar. 10, 2017;
[0004] U.S. Provisional Patent Application No. 62/470,080 filed on
Mar. 10, 2017; and
[0005] U.S. Provisional Patent Application No. 62/470,089 filed on
Mar. 10, 2017.
All of these provisional applications are hereby incorporated by
reference in their entirety.
TECHNICAL FIELD
[0006] This disclosure generally relates to pressure sensors. More
specifically, this disclosure relates to a pressure sensor having a
coplanar meter body with sensor overpressure protection.
BACKGROUND
[0007] A differential pressure transmitter generally operates by
providing two pressure values to a sensor. The sensor converts a
difference between the two pressure values into an electrical
signal, which can then undergo additional signal processing. To
achieve optimum sensitivity, the sensor may operate near a
differential pressure that can cause failure of the sensor. To
avoid damage to the sensor, an overpressure mechanism can be
employed to limit the differential pressure that is input to the
sensor.
[0008] Various techniques have been developed for overpressure
protection in differential pressure transmitters. However, these
techniques are typically implemented using a "dual head" package.
In a dual head package, a meter body has two opposing pressure
heads, an overpressure mechanism is positioned between the pressure
heads, and a sensor is mounted within or adjacent to the
overpressure mechanism. While effective, this approach can be
expensive and heavy, due among other things to the unique materials
often required to safely contain high pressure and corrosive
process fluids. Also, multiple pressure heads and their associated
bolts, nuts, gaskets, and other miscellaneous hardware are needed
in this approach to connect to a manifold that carries the process
fluids.
SUMMARY
[0009] This disclosure provides a pressure sensor having a coplanar
meter body with sensor overpressure protection.
[0010] In a first embodiment, an apparatus includes a sensor body
and a sensor configured to measure differential pressure. The
apparatus also includes first and second coplanar pressure inputs
in or on the sensor body, where the pressure inputs are configured
to provide multiple input pressures to the sensor. Each pressure
input includes a barrier diaphragm configured to move in response
to pressure and an overload diaphragm configured to limit movement
of the barrier diaphragm.
[0011] In a second embodiment, a system includes a manifold and a
pressure sensor mounted to the manifold. The pressure sensor
includes a sensor body and a sensor configured to measure
differential pressure. The pressure sensor also includes first and
second coplanar pressure inputs in or on the sensor body, where the
pressure inputs are configured to provide multiple input pressures
to the sensor. Each pressure input includes a barrier diaphragm
configured to move in response to pressure and an overload
diaphragm configured to limit movement of the barrier
diaphragm.
[0012] In a third embodiment, a method includes conveying multiple
input pressures to a sensor and measuring a differential pressure
using the sensor. The multiple input pressures are conveyed using
first and second coplanar pressure inputs in or on a sensor body.
Each pressure input includes a barrier diaphragm configured to move
in response to pressure and an overload diaphragm configured to
limit movement of the barrier diaphragm.
[0013] Other technical features may be readily apparent to one
skilled in the art from the following figures, descriptions, and
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] For a more complete understanding of this disclosure,
reference is now made to the following description, taken in
conjunction with the accompanying drawings, in which:
[0015] FIG. 1 illustrates an example industrial process control and
automation system according to this disclosure;
[0016] FIG. 2 illustrates an example differential pressure sensor
according to this disclosure;
[0017] FIG. 3 illustrates an example protection mechanism in a
differential pressure sensor according to this disclosure;
[0018] FIG. 4 illustrates example operation of a differential
pressure sensor with overpressure protection according to this
disclosure;
[0019] FIG. 5 illustrates an example use of a differential pressure
sensor with overpressure protection according to this disclosure;
and
[0020] FIG. 6 illustrates an example method for overpressure
protection of a pressure sensor having a coplanar meter body
according to this disclosure.
DETAILED DESCRIPTION
[0021] FIGS. 1 through 6, discussed below, and the various
embodiments used to describe the principles of the present
invention in this patent document are by way of illustration only
and should not be construed in any way to limit the scope of the
invention. Those skilled in the art will understand that the
principles of the invention may be implemented in any type of
suitably arranged device or system.
[0022] FIG. 1 illustrates an example industrial process control and
automation system 100 according to this disclosure. As shown in
FIG. 1, the system 100 includes various components that facilitate
production or processing of at least one product or other material.
For instance, the system 100 can be used to facilitate control over
components in one or multiple industrial plants. Each plant
represents one or more processing facilities (or one or more
portions thereof), such as one or more manufacturing facilities for
producing at least one product or other material. In general, each
plant may implement one or more industrial processes and can
individually or collectively be referred to as a process system. A
process system generally represents any system or portion thereof
configured to process one or more products or other materials in
some manner.
[0023] In FIG. 1, the system 100 includes one or more sensors 102a
and one or more actuators 102b. The sensors 102a and actuators 102b
represent components in a process system that may perform any of a
wide variety of functions. For example, the sensors 102a could
measure a wide variety of characteristics in the process system,
such as pressure, temperature, or flow rate. Also, the actuators
102b could alter a wide variety of characteristics in the process
system. Each of the sensors 102a includes any suitable structure
for measuring one or more characteristics in a process system. Each
of the actuators 102b includes any suitable structure for operating
on or affecting one or more conditions in a process system.
[0024] At least one network 104 is coupled to the sensors 102a and
actuators 102b. The network 104 facilitates interaction with the
sensors 102a and actuators 102b. For example, the network 104 could
transport measurement data from the sensors 102a and provide
control signals to the actuators 102b. The network 104 could
represent any suitable network or combination of networks. As
particular examples, the network 104 could represent at least one
Ethernet network, electrical signal network (such as a HART or
FOUNDATION FIELDBUS network), pneumatic control signal network, or
any other or additional type(s) of network(s).
[0025] The system 100 also includes various controllers 106. The
controllers 106 can be used in the system 100 to perform various
functions in order to control one or more industrial processes. For
example, a first set of controllers 106 may use measurements from
one or more sensors 102a to control the operation of one or more
actuators 102b. A second set of controllers 106 could be used to
optimize the control logic or other operations performed by the
first set of controllers. A third set of controllers 106 could be
used to perform additional functions.
[0026] Controllers 106 are often arranged hierarchically in a
system. For example, different controllers 106 could be used to
control individual actuators, collections of actuators forming
machines, collections of machines forming units, collections of
units forming plants, and collections of plants forming an
enterprise. A particular example of a hierarchical arrangement of
controllers 106 is defined as the "Purdue" model of process
control. The controllers 106 in different hierarchical levels can
communicate via one or more networks 108 and associated switches,
firewalls, and other components.
[0027] Each controller 106 includes any suitable structure for
controlling one or more aspects of an industrial process. At least
some of the controllers 106 could, for example, represent
proportional-integral-derivative (PID) controllers or multivariable
controllers, such as Robust Multivariable Predictive Control
Technology (RMPCT) controllers or other types of controllers
implementing model predictive control or other advanced predictive
control. As a particular example, each controller 106 could
represent a computing device running a real-time operating system,
a WINDOWS operating system, or other operating system.
[0028] Operator access to and interaction with the controllers 106
and other components of the system 100 can occur via various
operator consoles 110. Each operator console 110 could be used to
provide information to an operator and receive information from an
operator. For example, each operator console 110 could provide
information identifying a current state of an industrial process to
the operator, such as values of various process variables and
warnings, alarms, or other states associated with the industrial
process. Each operator console 110 could also receive information
affecting how the industrial process is controlled, such as by
receiving setpoints or control modes for process variables
controlled by the controllers 106 or other information that alters
or affects how the controllers 106 control the industrial
process.
[0029] Multiple operator consoles 110 can be grouped together and
used in one or more control rooms 112. Each control room 112 could
include any number of operator consoles 110 in any suitable
arrangement. In some embodiments, multiple control rooms 112 can be
used to control an industrial plant, such as when each control room
112 contains operator consoles 110 used to manage a discrete part
of the industrial plant.
[0030] Each operator console 110 includes any suitable structure
for displaying information to and interacting with an operator. For
example, each operator console 110 could include one or more
processing devices 114, such as one or more processors,
microprocessors, microcontrollers, field programmable gate arrays,
application specific integrated circuits, discrete logic devices,
or other processing or control devices. Each operator console 110
could also include one or more memories 116 storing instructions
and data used, generated, or collected by the processing device(s)
114. Each operator console 110 could further include one or more
network interfaces 118 that facilitate communication over at least
one wired or wireless network, such as one or more Ethernet
interfaces or wireless transceivers.
[0031] At least one of the sensors 102a in FIG. 1 could represent a
differential pressure transmitter. As noted above, a differential
pressure transmitter generally operates by providing two pressure
values to a sensor, which converts a difference between the two
pressure values into an electrical signal. To avoid damage to the
sensor, an overpressure mechanism can be employed to limit the
differential pressure that is input to the sensor.
[0032] Conventional approaches often only provide overpressure
protection in pressure transmitters with "dual head" packages. In a
dual head package, a meter body has two opposing pressure heads,
and an overpressure mechanism is positioned between the pressure
heads. However, in a "coplanar" meter body, the pressure inputs are
generally coplanar. As a result, the conventional approaches cannot
be used without significant modifications.
[0033] In accordance with this disclosure, a differential pressure
sensor having a coplanar meter body with sensor overpressure
protection is provided. This approach allows overpressure
protection to be provided in differential pressure sensors having
coplanar meter bodies. This approach reduces the size of the
pressure sensor compared to conventional pressure transmitters with
"dual head" packages. A pressure sensor with a coplanar meter body
and overpressure protection can achieve the same performance as
pressure sensors with dual head packages, but the coplanar meter
body is smaller and lighter, resulting in easier installation and
reduced cost. Also, a coplanar meter body can be mounted directly
to a manifold and thereby eliminate expensive corrosion-resistant
pressure heads, bolts, and other miscellaneous hardware. This can
again result in easier installation and reduced size and cost.
Moreover, since a coplanar meter body can be mounted directly to a
manifold, this can eliminate the use of two joints with gaskets,
thereby eliminating potential leak paths for toxic or corrosive
process fluids. In addition, providing overpressure protection can
allow multiple piezo-resistive or other sensors to be used on a
single integrated circuit chip or other structure, which allows for
multiple or redundant sensor measurements to be captured. As a
particular example, the same integrated circuit chip could include
sensors that output both differential and static pressure
measurements.
[0034] Additional details regarding a differential pressure sensor
having a coplanar meter body with sensor overpressure protection
are provided below. Note that these details relate to specific
implementations of the differential pressure sensor and that other
implementations could vary as needed or desired.
[0035] Although FIG. 1 illustrates one example of an industrial
process control and automation system 100, various changes may be
made to FIG. 1. For example, industrial control and automation
systems come in a wide variety of configurations. The system 100
shown in FIG. 1 is meant to illustrate one example operational
environment in which a differential pressure sensor could be
used.
[0036] FIG. 2 illustrates an example differential pressure sensor
200 according to this disclosure. For ease of explanation, the
differential pressure sensor 200 may be described as being used in
the industrial process control and automation system 100 of FIG. 1.
However, the differential pressure sensor 200 could be used in any
other suitable system, and the system need not relate to industrial
process control and automation.
[0037] As shown in FIG. 2, the differential pressure sensor 200
includes an adapter 202 and at least one sensor 204. The adapter
202 denotes a portion of the differential pressure sensor 200 in
which wires or other signal conductors can be connected to the
sensor 204. The outer surface of the adapter 202 can also be
threaded or otherwise configured to facilitate attachment of the
differential pressure sensor 200 to a larger device or system. The
adapter 202 could be formed from any suitable material(s) and in
any suitable manner. As a particular example, the adapter 202 could
be formed from metal.
[0038] The sensor 204 denotes a structure that senses multiple
input pressures and outputs a signal indicative of a difference
between the input pressures. For example, the sensor 204 could
output an electrical signal whose voltage or current varies
proportionally with the difference between the input pressures. The
sensor 204 includes any suitable differential pressure sensor, such
as a piezo-resistive or capacitive sensor. As noted above, multiple
sensors 204 could also be used, such as sensors that output both
differential and static pressure measurements. Also, the multiple
sensors 204 may or may not be implemented on a single integrated
circuit chip. Each sensor 204 includes any suitable structure for
measuring pressure.
[0039] The differential pressure sensor 200 also includes a
coplanar body 206, which denotes a portion of the differential
pressure sensor 200 in which multiple pressure inputs are located.
The pressure inputs are generally located on a common plane, which
is why the body 206 is referred to as a "coplanar" body. The
coplanar body 206 could be formed from any suitable material(s) and
in any suitable manner. As a particular example, the coplanar body
206 could be formed from metal. Note that the adapter 202 and the
coplanar body 206 could be formed integrally or as separate pieces
that are connected together, such as by welding.
[0040] The pressure inputs in the differential pressure sensor 200
are implemented using a high-pressure barrier diaphragm 208 and a
low-pressure barrier diaphragm 210. Each of the barrier diaphragms
208 and 210 represents a barrier that allows pressure to be
transmitted into the differential pressure sensor 200 while
preventing process fluid (such as oil, gas, or other high pressure
and corrosive fluid) from entering into the differential pressure
sensor 200. The barrier diaphragms 208 and 210 represent flexible
membranes that can move up or down in FIG. 2 based on the amount of
pressure applied to the barrier diaphragms 208 and 210.
[0041] Each of the barrier diaphragms 208 and 210 denotes any
suitable flexible membrane, such as a metallic membrane. Each of
the barrier diaphragms 208 and 210 could also have any suitable
size, shape, and dimensions. In particular embodiments, the barrier
diaphragms 208 and 210 are small enough and spaced apart to fit
within the established bolt pattern for industry-standard DIN
manifolds. This allows the differential pressure sensor 200 to be
mounted directly to a manifold.
[0042] Pressures from the barrier diaphragms 208 and 210 are
transmitted to the sensor 204 via a fill fluid that travels through
various passages 212. The fill fluid could denote an incompressible
fluid, so pressure applied by the barrier diaphragm 208 or 210 is
conveyed by the fill fluid to the sensor 204. The fill fluid
denotes any suitable fluid for conveying pressure, such as silicone
oil or other suitable fluid. Each passage 212 denotes any suitable
passageway for fill fluid.
[0043] The pressure sensor 200 may optionally contain fluid
expansion compensation elements 214a-214b, which are used to reduce
the thermal expansion effect of the fill fluid. In some
embodiments, it may be necessary or desirable to reduce or minimize
the fluid travel of the fill fluid through the passages 212.
However, this may be complicated by the need to operate the
pressure sensor 200 over a large temperature range. Since the fluid
expansion properties of the fill fluid may greatly exceed those of
the body 206, this results in a larger volume of fluid as the
temperature increases. To help handle this issue, the fluid
expansion compensation elements 214a-214b can be used and denote
cylindrical or other components that encircle or surround various
ones of the passages 212. The fluid expansion compensation elements
214a-214b can be formed using a low thermal expansion material,
such as INVAR (FeNi36 or 64FeNi) or other material with low thermal
expansion as compared to the material of the coplanar body 206.
[0044] Each barrier diaphragm 208 and 210 has an associated
overload or overpressure protection mechanism 216 and 218,
respectively. The protection mechanisms 216 and 218 generally
provide protection against overpressure conditions that can damage
the differential pressure sensor 200. In a typical overpressure
mechanism for a "dual head" package, a center diaphragm is
positioned between and generally parallel to two opposing barrier
diaphragms. This design is effective when the pressure inputs are
on opposite sides of the meter body. However, as can be seen in
FIG. 2, this conventional approach cannot be used cost-effectively
in the differential pressure sensor 200 since the barrier
diaphragms 208 and 210 are coplanar rather than on opposite sides
of the body 206. Instead, the protection mechanisms 216 and 218
implement separate protection for the sensor 204. Each of the
protection mechanisms 216 and 218 includes any suitable structure
for providing structural reinforcement and overpressure protection.
Additional details regarding example operations of the protection
mechanisms 216 and 218 are provided below with respect to FIG.
4.
[0045] A coplanar meter body can be smaller and lighter than a
"dual head" package. The protection mechanisms 216 and 218 are
capable of fitting into the reduced size of a coplanar meter body,
so overpressure protection can be provided in a smaller pressure
sensor. Moreover, a coplanar meter body can be mounted directly to
a manifold that carries a process fluid. Not only does this
approach result in lighter and more easily installed devices, this
approach also saves the cost of corrosion-resistant pressure heads
and associated hardware.
[0046] Although FIG. 2 illustrates one example of a differential
pressure sensor 200, various changes may be made to FIG. 2. For
example, the sizes, shapes, and relative dimensions of the
components in FIG. 2 are for illustration only. Also, other
arrangements of the components in FIG. 2 could be used in a
differential pressure sensor. In addition, the overall form factor
for the differential pressure sensor 200 could vary as needed or
desired.
[0047] FIG. 3 illustrates an example protection mechanism 216, 218
in a differential pressure sensor according to this disclosure. For
ease of explanation, the protection mechanism 216, 218 shown in
FIG. 3 is described with respect to the differential pressure
sensor 200 of FIG. 2. However, the protection mechanism 216, 218
could be used with any other suitable pressure sensor.
[0048] As shown in FIG. 3, the protection mechanism 216, 218 is
implemented as an additional diaphragm that is placed behind one of
the barrier diaphragms 208, 210 between that barrier diaphragm and
the body 206. The protection mechanism 216, 218 could be thicker
than the barrier diaphragm 208, 210. The protection mechanism 216,
218 operates to protect the sensor 204 from damage. For example,
the protection mechanism 216 will move with application of pressure
and allow the barrier diaphragm 210 to move and lay against the
protection mechanism 218, thus stopping the further input of
pressure. In a similar manner, the protection mechanism 218 will
move with application of pressure and allow the barrier diaphragm
208 to move and lay against the protection mechanism 216, thus
stopping the further input of pressure. In this way, individual
operation of each protection mechanism 216, 218 will protect the
sensor 204 from damage due to overpressure from either pressure
input.
[0049] In some embodiments, the protection mechanism 216, 218 is
attached to the body 206 of the differential pressure sensor 200.
The barrier diaphragm 208, 210 is then placed over the protection
mechanism 216, 218 and attached to the body 206 of the differential
pressure sensor 200. In particular embodiments, the protection
mechanism 216, 218 and the barrier diaphragm 208, 210 are attached
to the body 206 using laser welds 302. Moreover, a weld or other
seal ring 304 could be placed around the peripheries of the barrier
diaphragm 208, 210 and the protection mechanism 216, 218. The seal
ring 304 can be used to house a gasket or O-ring 306 that seals an
external manifold or other component that is used to input
pressures to the sensor 200.
[0050] Although FIG. 3 illustrates one example of a protection
mechanism 216, 218 in a differential pressure sensor, various
changes may be made to FIG. 3. For example, the sizes, shapes, and
relative dimensions of the components in FIG. 3 are for
illustration only.
[0051] FIG. 4 illustrates example operation of a differential
pressure sensor with overpressure protection according to this
disclosure. For ease of explanation, the operations shown in FIG. 4
are described with respect to the differential pressure sensor 200
of FIG. 2. However, these operations could occur using any other
suitable pressure sensor.
[0052] As shown in FIG. 4, internal porting is implemented in the
body 206 using the passages 212 to transfer two pressure inputs to
the sensor 204. A high-pressure port 402 provides a higher-pressure
input to the sensor 204, and a low-pressure port 404 provides a
lower-pressure input to the sensor 204.
[0053] A fill fluid 406 fills a gap between the barrier diaphragm
208 and the protection mechanism (overload diaphragm) 216. The fill
fluid 406 is ported via the port 402 to both the high-pressure side
of the sensor 204 and to a gap between the body 206 and the other
protection mechanism (overload diaphragm) 218. Similarly, a fill
fluid 408 fills the gap between the barrier diaphragm 210 and the
protection mechanism (overload diaphragm) 218. The fill fluid 408
is ported via the port 404 to both the low-pressure side of the
sensor 204 and to a gap between the body 206 and the other
protection mechanism (overload diaphragm) 216.
[0054] During the application of high-side pressure, the pressure
is transmitted from the barrier diaphragm 208 to the fill fluid 406
and then to the sensor 204 and to the gap between the other
protection mechanism (overload diaphragm) 218 and the body 206.
This causes the protection mechanism 218 to deflect away from the
body 206, increasing the gap between the body 206 and the
protection mechanism 218. Meanwhile, the gap between the barrier
diaphragm 208 and the protection mechanism 216 is reduced. When
sufficient fill fluid 406 has moved to eliminate the gap between
the barrier diaphragm 208 and the protection mechanism 216, the
barrier diaphragm 208 and the protection mechanism 216 nest
together, and no additional pressure will be transmitted to the
sensor 204, thus providing overpressure protection for the sensor
204.
[0055] In a similar manner, during the application of low-side
pressure, the pressure is transmitted from the barrier diaphragm
210 to the fill fluid 408 and then to the sensor 204 and to the gap
between the other protection mechanism (overload diaphragm) 216 and
the body 206. This causes the protection mechanism 216 to deflect
away from the body 206, increasing the gap between the body 206 and
the protection mechanism 216. Meanwhile, the gap between the
barrier diaphragm 210 and the protection mechanism 218 is reduced.
When sufficient fill fluid 408 has moved to eliminate the gap
between the barrier diaphragm 210 and the protection mechanism 218,
the barrier diaphragm 210 and the protection mechanism 218 nest
together, and no additional pressure will be transmitted to the
sensor 204, thus providing overpressure protection for the sensor
204.
[0056] Although FIG. 4 illustrates one example of operation of a
differential pressure sensor with overpressure protection, various
changes may be made to FIG. 4. For example, the sizes, shapes, and
relative dimensions of the components in FIG. 4 are for
illustration only.
[0057] FIG. 5 illustrates an example use of a differential pressure
sensor 200 with overpressure protection according to this
disclosure. For ease of explanation, the use shown in FIG. 5 is
described with respect to the differential pressure sensor 200 of
FIG. 2. However, the differential pressure sensor 200 could be used
in any other suitable manner.
[0058] As shown in FIG. 5, the differential pressure sensor 200 is
mounted directly to a manifold 502. The manifold 502 denotes any
suitable structure that is configured to transport at least one
process fluid 504. As noted above, the manifold 502 could be
configured to transport one or more corrosive process fluids at
high pressures. The manifold 502 could have any suitable size,
shape, and dimensions and could be formed from any suitable
material(s).
[0059] The differential pressure sensor 200 can be mounted directly
to openings 506 of the manifold 502. The openings 506 could have
any suitable size, shape, and dimensions and could be separated by
any suitable distance. As noted above, for example, the manifold
502 could denote an industry-standard DIN manifold, and the barrier
diaphragms 208 and 210 can be small enough and spaced apart to fit
within the established bolt pattern for the DIN manifold.
[0060] Although FIG. 5 illustrates one example use of a
differential pressure sensor 200 with overpressure protection,
various changes may be made to FIG. 5. For example, the
differential pressure sensor 200 could be used in any other
suitable manner and need not be used with a manifold.
[0061] FIG. 6 illustrates an example method 600 for overpressure
protection of a pressure sensor having a coplanar meter body
according to this disclosure. For ease of explanation, the method
600 shown in FIG. 6 is described with respect to the differential
pressure sensor 200 of FIG. 2 operating as shown in FIG. 4.
However, the method 600 could be used with any other suitable
pressure sensor.
[0062] As shown in FIG. 6, input pressures are received at barrier
diaphragms of a differential pressure sensor at step 602. This
could include, for example, receiving input pressures at the
barrier diaphragms 208 and 210 of the pressure sensor 200. As a
particular example, this could include receiving input pressures at
the barrier diaphragms 208 and 210 of the pressure sensor 200
through openings 506 of the manifold 502. The input pressures are
transferred to at least one pressure sensor at step 604. This could
include, for example, the fill fluid 406 and 408 transferring the
input pressures from the barrier diaphragms 208 and 210 to the at
least one sensor 204 through the ports 402 and 404. One or more
pressure measurements are generated at step 606. This could
include, for example, the at least one sensor 204 generating an
electrical signal whose voltage or current varies proportionally
with the difference between the input pressures. This could also
include different sensors 204 generating multiple pressure
measurements, such as multiple differential pressure measurements
or differential and static pressure measurements.
[0063] If no overpressure condition exists at step 608, the process
returns to step 602 so that additional pressure measurements can be
generated. However, if an overpressure condition on one of the
barrier diaphragms exists at step 608, the process includes
additional steps used to protect the pressure sensor(s) from
damage. For example, during an overpressure condition on a
specified one of the barrier diaphragms, fill fluid is transferred
out of a space between the specified barrier diaphragm and its
associated overload diaphragm at step 610. This could include, for
example, the fill fluid 406 between the barrier diaphragm 208 and
the protection mechanism 216 moving via the port 402 to a gap
between the body 206 and the other protection mechanism 218. This
could also include the fill fluid 408 between the barrier diaphragm
210 and the protection mechanism 218 moving via the port 404 to a
gap between the body 206 and the other protection mechanism
216.
[0064] If enough fill fluid is transferred, the specified barrier
diaphragm eventually nests against its associated overload
diaphragm at step 612. This could include, for example, the barrier
diaphragm 208 contacting and resting against the protection
mechanism 216 or the barrier diaphragm 210 contacting and resting
against the protection mechanism 218. This helps to prevent
additional pressure from reaching the pressure sensor(s) at step
614. This could include, for example, the associated protection
mechanism 216, 218 preventing the specified barrier diaphragm 208,
210 from further movement inward, which could otherwise apply an
excessive pressure via the fill fluid 406, 408 to the pressure
sensor(s) 204.
[0065] Although FIG. 6 illustrates one example of a method 600 for
overpressure protection of a pressure sensor having a coplanar
meter body, various changes may be made to FIG. 6. For example,
while shown as a series of steps, various steps in FIG. 6 could
overlap, occur in parallel, occur in a different order, or occur
any number of times. As a particular example, steps 604-606 could
occur at the same time as steps 608-614 so that overpressure
protection is provided in parallel with the generation of pressure
measurements.
[0066] It may be advantageous to set forth definitions of certain
words and phrases used throughout this patent document. The terms
"include" and "comprise," as well as derivatives thereof, mean
inclusion without limitation. The term "or" is inclusive, meaning
and/or. The phrase "associated with," as well as derivatives
thereof, may mean to include, be included within, interconnect
with, contain, be contained within, connect to or with, couple to
or with, be communicable with, cooperate with, interleave,
juxtapose, be proximate to, be bound to or with, have, have a
property of, have a relationship to or with, or the like. The
phrase "at least one of," when used with a list of items, means
that different combinations of one or more of the listed items may
be used, and only one item in the list may be needed. For example,
"at least one of: A, B, and C" includes any of the following
combinations: A, B, C, A and B, A and C, B and C, and A and B and
C.
[0067] The description in the present application should not be
read as implying that any particular element, step, or function is
an essential or critical element that must be included in the claim
scope. The scope of patented subject matter is defined only by the
allowed claims. Moreover, none of the claims invokes 35 U.S.C.
.sctn. 112(f) with respect to any of the appended claims or claim
elements unless the exact words "means for" or "step for" are
explicitly used in the particular claim, followed by a participle
phrase identifying a function. Use of terms such as (but not
limited to) "mechanism," "module," "device," "unit," "component,"
"element," "member," "apparatus," "machine," "system," "processor,"
or "controller" within a claim is understood and intended to refer
to structures known to those skilled in the relevant art, as
further modified or enhanced by the features of the claims
themselves, and is not intended to invoke 35 U.S.C. .sctn.
112(f).
[0068] While this disclosure has described certain embodiments and
generally associated methods, alterations and permutations of these
embodiments and methods will be apparent to those skilled in the
art. Accordingly, the above description of example embodiments does
not define or constrain this disclosure. Other changes,
substitutions, and alterations are also possible without departing
from the spirit and scope of this disclosure, as defined by the
following claims.
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