WO2002014800A1

WO2002014800A1 - Batteryless electronic register

Info

Publication number: WO2002014800A1
Application number: PCT/US2001/041743
Authority: WO
Inventors: David Hamilton
Original assignee: Schlumberger Resource Management Services Inc
Current assignee: Atos Origin IT Services Inc
Priority date: 2000-08-17
Filing date: 2001-08-16
Publication date: 2002-02-21
Anticipated expiration: 2003-02-17
Also published as: AU2001287184A1

Abstract

A batteryless flow meter (20) has a rotatable element (32) responsive to fluid flow and renewable power source. In particular, a solar cell (46) is used to provide power to the flow meter's digital display and its associated electronics (44). As part of the power system, there is a capacitor capable of providing enough power to operate the flow meter should there be a temporary interruption in the supply of energy from the solar cell (46).

Description

A Solar Cell Powered Flow Meter.

BACKGROUND OF THE INVENTION

This invention generally relates to an apparatus for measuring fluid flow. More specifically, the present invention relates to a device for providing power to an apparatus for measuring fluid flow. Still further, the present invention relates to a device for providing power to both a display and that portion of a memory associated with such display, all associated with an apparatus for measuring fluid flow. Conventional devices for fluid measurement are known. Various such devices may be limited to measuring the flow rate of a fluid or may be configured for totalizing the volume of a fluid flow. In general, such devices function by placing a rotatable element in the path of fluid flow. The energy of the moving fluid is utilized to cause the rotatable element, such as a turbine, to rotate on a shaft. Means are provided for detecting the rotational speed of the element and, in some devices, to determine the total (i.e. , for totalizing) number of revolutions. Base on predetermined calibrations, the volume of fluid passing through the associated passageway during one revolution is known. Simple mathematical calculations can then be performed to determine the total volume of fluid flow during a given period.

In order for such flow meters to be of any informational value to utility, oil, and/or other industries, such meters must be capable of displaying their measured values. As is well known to those of ordinary skill in the art, some meters have used (and some still do use) a series of rotating geared discs which are directly or indirectly connected to the shaft on which the rotatable element is located. These geared discs have measurement indicia printed directly on them. By taking two readings of the discs, separated in time, the total volumetric flow over a period can be determined by the difference in the two readings .

More advanced flow meters utilize solid-state digital electronics to determine the flow characteristics (e.g. , direction, rotation, partial flow, pulse flow, etc.), the volume of the flow, the flow rate, and even to perform diagnostic checks on the meter ' s measurement systems . Additionally, such meters typically use solid-state digital displays, including microprocessors and non-volatile memory, and a non-volatile totalizer to replace the prior art rotatable geared discs .

Prior art flow meters typically rely on a long-life battery as their power source for making measurements and for displaying their readings.

Several examples of flow meters utilizing battery- powered circuitry and displays are disclosed in U.S. Patent No. 4,787,253, issued November 29, 1988 to deFasselle et al . ; U.S. Patent No. 4,848,164, issued July 18, 1989 to Ouarve et al . ; U.S. Patent No. 4,945,754, issued August 7, 1990 to issman, Jr . et al . ; and U.S. Patent No. 5,659,300, issued August 19, 1997 to Dresselhuvs et al . ; the disclosures of all of which are fully incorporated herein by reference.

While useful for their purposes, such meters may suffer complete failure when there is a loss of power due to tampering or should there be depletion of the battery. In such cases, the flow meter fails to properly record the consumption or transfer of a fluid until such time as the battery is replaced. As a result, such a meter becomes of little or no use to the user (i.e. , the company which relies on the meter for consumption-based revenues) until the meter's failure is known and acted upon. It is, therefore, desirable to provide an effective self-sustaining and/or renewable power source that will allow the storage of enough power to maintain the functionality of a flow meter (i.e. , the measurement of a value, its storage into non-volatile memory, and the display of that value to a user) for a short period of time despite an otherwise catastrophic interruption in the power supply to the display and its associated memory and electronics . SUMMARY OF THE INVENTION

The present invention recognizes and addresses various of the foregoing limitations and drawbacks, and others, concerning the storage of measured flow data into non-volatile memory and the display of that data. Therefore, the present invention provides a new device for supplying electrical power to a display and the associated electronics that interface with such display on a fluid flow meter. It is, therefor, a principle object of the subject invention to provide a new source of power to a fluid flow meter. More particularly, it is a principle object of the subject invention to provide such a source of power for operation of a display of such a meter.

Another more particular object of the subject invention is to provide a power source (separate from a typical main power source) sufficient to allow operation of a display of a fluid flow meter and all of the associated electronics which store the meter's measurements. It is a further general object of the subject invention is to provide a power source sufficient to allow operation of a display of a fluid flow meter, all of the associated electronics, and that portion of a non-volatile totalizer that interfaces with such a display. In such context, it is still a further general object of the present invention to provide a power source comprising energy collection-conversion and energy storage devices capable of providing enough energy to operate a display, all the associated electronics and that portion of a non-volatile totalizer that interfaces with such a display of a fluid flow meter despite a temporary interruption in a main power source. Additional objects and advantages of the invention are set forth in, or will be apparent to those of ordinary skill in the art from, the detailed description as follows. Also, it should be further appreciated that modifications and variations to the specifically illustrated and discussed features and materials hereof may be practiced in various embodiments and uses of this invention without departing from the spirit and scope thereof, by virtue of present reference thereto. Such variations may include, but are not limited to, substitutions of equivalent means, features, and materials for those shown or discussed, and the functional or positional reversal of various parts, features, or the like. Still further, it is to be understood that different embodiments, as well as different presently preferred embodiments, of this invention, may include various combinations or configurations of presently disclosed features, elements, or their equivalents (including combinations of features or configurations thereof not expressly shown in the figures or stated in the detailed description) . These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the principles of the invention. In one exemplary embodiment of the present invention a fluid flow meter comprises a residential utility meter with an electronic display. One of ordinary skill in the art would recognize that other embodiments of the present invention could include exemplary flow meters for use with oil, gas, chemicals, and/or any other fluid (herein referring to a fluid in its broadest sense to include both liquids and/or gases) where accurate measurement of fluid flow is required. The flow meter in such an exemplary embodiment may include a first housing having an inlet and an outlet and a second housing. Between such inlet and such outlet preferably is an intermediate chamber. Within such chamber may be a turbine or equivalent which rotates in response to the fluid flow. The first housing., second housing, intermediate chamber and turbine share a common central vertical axis. Such turbine may be mechanically connected to a magnet which rotates about the common vertical axis in conjunction with the turbine .

A sensor, located in the second housing, detects the rotation of such magnet and sends such information to a totalizer. One of ordinary skill in the art would recognize that any form of detection, including for example, magnetic field fluctuation, optical detection, and/or mechanical tallying, may be utilized to determine either a partial or full rotation of such magnet.

The totalizer, located with the primary circuitry of such meter in the second housing, may maintain a running count of the indicators it receives of the magnet's rotation. The measured totalizer value may then be converted to a total volumetric flow and/or flow rate and may be recorded in non-volatile memory and/or displayed. Power is supplied to the display from a solar cell. In another exemplary embodiment, the flow meter comprises a first housing defining an inlet, an outlet, and an intermediate chamber, and a second housing. Within such intermediate chamber is a rotating disc which is responsive to the fluid flow. Mechanically connected to the rotating disc is a first magnet . Located in the second housing is a second magnet in magnetic communication with the first magnet. Such rotating disc, first and second magnets share a common axis of rotation. As the first magnet rotates the second magnet rotates in precise coordination with the first magnet. A sensor may detect the number of revolutions or portions thereof of the second magnet and a non- volatile circuit totalizes the number of rotations which may then be converted to either flow rate or volumetric flow data. Such data may then be sent to a display. The display, its associated electronics and that portion of such a non-volatile totalizer which interfaces with the display are powered by a solar cell .

One of ordinary skill will recognize that an exemplary solar cell, alone or in combination with, a power-generating sensor, a flow-powered turbine and/or a separate electrical connection, would be capable of powering any individual or even all features of such a flow meter. An exemplary meter, in accordance with the present invention, may have a main power source for operating the non-volatile totalizer and an exemplary solar cell to power such a display and its associated electronics. In certain other embodiments, such a solar cell may additionally power a portion of the non-volatile totalizer.

In yet another exemplary embodiment, a flow meter comprises a first housing with an inlet, an outlet, an intermediate chamber, and a second housing. Within the intermediate chamber may be a nutating disc which is responsive to the fluid flow. Such nutating disc is in mechanical communication with a magnet. One of ordinary skill will recognize that any number of magnets may be used . The first housing, second housing, intermediate chamber, and nutating disc share a common central vertical axis.

Such magnet is located on the outer perimeter of such nutating disc. A sensor, located in the second housing, detects the passage of the magnet by detecting magnetic field fluctuations. A nonvolatile circuit totalizes the number of rotations or portions thereof detected by such sensor and may convert that into either flow rate or volumetric flow data. The totalized data is then available for showing on the flow meter's display. In addition to the sensor, the non-volatile totalizer circuitry and the display are located in the second housing. The display, its associated electronics and that portion of the non-volatile totalizer circuitry which interfaces with the display may be powered by a solar cell . In the event of an interruption of the solar cell provided power, a capacitive device is included to store a temporary power charge to operate the display and that portion of the non-volatile totalizer circuitry that interfaces with such display's electronics. BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:

FIG. 1 is a perspective and partial cross- sectional view of an exemplary flow meter for use with an exemplary embodiment in accordance with the subject invention, and showing a nutating disc for measuring fluid flow;

FIG. 2 is a schematic diagram of an exemplary fluid flow meter system incorporating the present invention representing an exemplary solar power collection cell associated with a capacitor for operating both some display electronics and its associated portion of the non-volatile totalizer's memory; and

FIG. 3 is a top plan view of a conventional external view placement of a typically battery- powered flow meter display.

FIG. 4 is a top plan view of the conventional battery-powered flow meter of FIG. 3 including the solar cells of the present invention.

Repeat use of reference characters throughout the present specification and appended drawings is intended to represent the same or analogous features or elements of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to presently preferred embodiments of the invention, examples of which are fully represented in the accompanying drawings. Such examples are provided by way of an explanation of the invention, not limitation thereof. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention, without departing from the spirit and scope thereof. For instance, features illustrated or described as part of one embodiment can be used on another embodiment to yield a still further embodiment. Still further, variations in selection of materials and/or characteristics may^¬ be practiced, to satisfy particular desired user criteria. Thus, it is intended that the present invention cover such modifications and variations as come within the scope of the present features and their equivalents.

As referenced above, the present invention is particularly concerned with a fluid flow meter including a self-sustaining and renewable power source for operating at least the display and its associated electronics. Figure 1 depicts a fluid flow meter 20 representing an exemplary embodiment of the present invention. Flow meter 20 includes a first housing 22 detachably connected to a second housing 24. Detachability allows for the second housing 24 to be readily substituted during the life of the fluid meter 20 and thereby facilitates replacement or changes in features or repairs. For example, the second housing 24 may provide a chamber or interior for including a register to provide mechanical recording and display of fluid measurements. Alternatively, the second housing 24 may be substituted so as to include solid-state digital electronics, including a totalizer for recording fluid measurements and a digital display. Detachability is not required by the present invention; the first housing 22 and second housing 24 may also be relatively permanently connected (i.e. , not intended to be separated for normal service purposes) . The first housing 22 provides an inlet 26 and an outlet 28 for fluid flow, as well as, an intermediate chamber 30 for a fluid flow responsive rotating element 32 that converts the kinetic energy of the moving fluid into a measurable rotation or other measurable movement. For example, by nutating about axis A-A, the rotating element 32 translates the kinetic energy of fluid flowing through the meter 20 into the rotation of an element, such as a first magnet 34. However, the present invention is not limited to the particular rotating element 32 depicted in Fig. 1, and may include any mechanism that can translate the kinetic energy of a flowing fluid into a measurable movement. By way of example only, the rotating element 32 may also be constructed from a rotatable member, such as a turbine, rotor, disc, or other such mechanisms. For the embodiment shown in Fig. 1, the rotating element 32 is encased within a cartridge 36.

Within the second housing 24 of the exemplary embodiment is a second magnet 38 in magnetic communication with the first magnet 34. As such first magnet 34 rotates in response to its mechanical connection to the rotating element 32, the second magnet 38 exactly mimics the motions of the first magnet 34. One of ordinary skill in the art would recognize various other methods for translating the rotational motion of a rotating element into a measurable motion, any of which could also be utilized and remain within the spirit and scope of the present invention. For example, a magnetically activated reed switch could be placed so as to open and close with the passage of a magnet affixed to an outer periphery of the rotating element 32. The opening or closing of the reed switch may be used as a signal of a completed rotation of the rotating element 32.

As best seen in Figure 2 , located within such second housing 24 is a sensor 40 configured to detect the magnetic field of the second magnet 38. Any sensor 40 capable of detecting changes in the magnetic field of a magnet may be utilized. One such particular sensor that may be applied is referred to generally as a "Wiegand" wire. Specifically, the sensor 40 detects the rotation of the magnetic field or magnetic flux of the second magnet 38. For each complete revolution of the second magnet 38, a pulse indicating one revolution is sent to the non-volatile totalizer 42. One of ordinary skill in the art would realize that such pulses could also be used to represent partial rotations of the second magnet 38 and thus the value maintained within the non-volatile totalizer 42 would represent portions of a rotation. The non-volatile totalizer 42 or register may be used to maintain a real-time running count of the total number of revolutions or partial revolutions of the rotating element 32. In accordance with the present invention, prior calibration of the rotating element 32 and the known volume of the intermediate chamber 30 would allow for direct calculation of the flow rate or total volume of fluid flow through the flow meter 20. The non-volatile totalizer 42 is in electrical communication with the display 44. The display electronics and display 44 are preferably solid- state digital electronics including a microprocessor and a liquid crystal display (LCD) (not shown) . The display 44 of the present invention is not limited to an LCD as specified and may include any other (preferably low power) display technology sufficient to exhibit the measured or calculated values of the meter 20. Figure 3 shows an exemplary prior art placement of a display 44 of a flow meter 20. If practiced in accordance with the present invention, such display 44 would be located at the top of the second housing 24 near a solar cell 46 (see Figure 2) .

In accordance with the present invention, a solar cell 46 may be provided to power the display electronics 44 and that portion of the non-volatile totalizer 42 that communicates with the display 44. One of ordinary skill in the art will recognize that any solar cell 46 capable of providing sufficient power for short periods of time in ambient light conditions would be satisfactory in the present invention.

The inclusion of such a solar cell 46 obviates the need for an internal battery or external power connection as is required by typical prior art flow meters. The elimination of the need for a battery or external power connection allows for the life of the flow meter 20 to be enhanced significantly. The limiting factor in the life of the flow meter 20 then becomes the life of the electronics within the second housing 24.

Such a solar cell 46 may be attached in any known manner to the exterior of the flow meter's first 22 or second 24 housings. In particular, the solar cell 46 need only be placed in such a location as would allow ambient light sufficient to power the display 44 to act upon the solar cell 46. Such placement, however, must consider the need to protect the solar cell 46 from the environment. More precisely, the solar cell 46 must be protected from prolonged or continuous exposure to the elements. Such protection may be achieved through the use of a clear covering over the solar cell 46 or by any other of the known manners of protection for solar cells 46. Such a cover would allow passage of the solar radiation necessary to power the solar cell 46 without directly exposing such a cell to the ravages of nature (i.e. , wind, rain, snow, ice, etc . ) .

In addition to the solar cell 46, the power management system of the flow meter 20 may include a capacitive device 48, preferably a relatively large capacitance capacitor which can store power as needed or eliminate excess power to ground. The capacitive device 48 may act to power the display electronics 44 and that portion of the non-volatile totalizer 42 which interacts directly with the display electronics 44 in the event that the solar cell 46 temporarily lost its direct line of sight to the sun.

Although a preferred embodiment of the invention has been described using specific terms and devices, such description is for illustrative purposes only. The words used are words of description rather than of limitation. It is to be understood that changes and variations may be made by those of ordinary skill in the art without departing from the spirit or the scope of the present invention, which is set forth in the following claims. In addition, it should be understood that aspects of various other embodiments may be interchanged both in whole or in part. Therefore, the spirit and scope of the appended claims should not be limited to the description of the exemplary preferred version or versions contained herein.

Claims

WHAT IS CLAIMED IS:

1. A flow meter, comprising: a) a first housing having an inlet, an outlet and an intermediate chamber, configured to allow fluid flow to enter said inlet, pass through said intermediate chamber, and exit through said outlet; b) a rotating member responsive to said fluid flow within said intermediate chamber; c) a second housing having a sensor for detecting indications of a partial or complete revolution of said rotating member; d) a totalizer for maintaining a count of said indications detected by said sensor; e) a display for exhibiting a value based upon the count maintained by the totalizer; and f) a power source for providing power to said display.

2. A flow meter as in claim 1, wherein said power source comprises a solar cell .

3. A flow meter as in claim 2, wherein said power source further comprises a capacitive element for storing power and for either releasing said stored power when any interruption of power from said solar cell is detected or grounding excess power .

4. A flow meter as in claim 3, wherein said solar cell further powers that portion of said totalizer that interfaces with said display.

5. A flow meter as in claim 1, wherein said totalizer is non-volatile.

6. A flow meter as in claim 1, wherein said first housing is non-magnetic.

7. A flow meter as in claim 6, wherein said first housing further comprises a magnet in mechanical communication with said rotating member.

8. A flow meter as in claim 7, wherein said rotating member is a nutating disc.

9. A flow meter as in claim 8, wherein said sensor is a Wiegand sensor.

10. A flow meter as in claim 1, wherein said non-volatile totalizer is located within and said display is located on said second housing.

11. A flow meter as in claim 1, wherein said totalizer comprises a microprocessor and a nonvolatile memory.

12. A resource flow conductor, comprising: a) a first housing with a central vertical axis having an inlet, an outlet, and further having an intermediate chamber, said first housing configured to allow fluid flow to enter said inlet, pass through said intermediate chamber, and exit through said outlet; b) a rotating member responsive to said fluid flow within said intermediate chamber; c) a second housing having a sensor for detecting indications of a partial or complete revolutions of said rotating member; d) a non-volatile totalizer for maintaining a count of the number of said indications detected by said sensor; e) a display for exhibiting a value based upon the count maintained within said non-volatile totalizer; and f) a power source for collecting and storing power to operate said display.

13. A resource flow conductor as in claim 12, wherein said power source comprises a solar cell .

14. A resource flow conductor as in claim 13, wherein said power source further comprises a capacitive element for storing power and releasing said stored power when any interruption in power from said solar cell is detected.

15. A flow meter as in claim 12, wherein said display and said solar cell are located on said second housing.

16. A flow meter as in claim 12, wherein said non-volatile totalizer is located within said second housing.

17. A resource flow conductor as in claim 12, wherein said first and said second housings are non-magnetic .

18. A resource flow conductor as in claim 17, further including a first magnet in said first housing and a second magnet in said second housing, said first magnet being in mechanical communication with said rotating member, said second magnet being in magnetic communication with said first magnet, said second magnet rotating in direct relation to the rotation of the first magnet.

19. A resource flow conductor as in claim 18, wherein said sensor is a Wiegand sensor.

20. A resource flow conductor as in claim 19, wherein said sensor detects the number of rotations or partial rotations of said rotating element by detecting corresponding rotations or portions thereof of said second magnet .

21. A resource flow conductor as in claim 12, wherein said fluid flow responsive rotating member is a nutating disc.

22. A fluid flow meter, comprising: a) a first housing having a central vertical axis, an inlet, an outlet, and an intermediate chamber, said intermediate chamber encompassing a portion of said central vertical axis, said first housing configured to allow fluid flow to enter said inlet, pass through said intermediate chamber, and exit through said outlet; b) a fluid flow responsive nutating disc within said intermediate chamber, said nutating disc having an axis of rotation coincident with said central vertical axis; c) a second housing having a Wiegand sensor for detecting indications of a revolution or portion thereof of said nutating disc; d) a non-volatile totalizer for maintaining a count of the number of indications detected by said sensor; e) a display for exhibiting a value based upon said count maintained within said totalizer; and f) a power source including a solar cell for collecting and storing power to operate said display.

23. A fluid flow meter as in claim 22, wherein said power source further comprises a capacitive element for storing power sufficient to operate said display when an interruption in power from said solar cell is detected.

24. A fluid flow meter as in claim 22, wherein said housing is non-magnetic.

25. A fluid flow meter as in claim 22, wherein said first housing further comprises a magnet in mechanical communication with said nutating disc.

26. A fluid flow meter as in claim 22, wherein said non-volatile totalizer is located within said second housing.

27. A fluid flow meter as in claim 22, wherein said display and said solar cell are located on said second housing.