• 专利附录
  • 专利说明
  • 权利要求
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    • 专利摘要:
    FLUID FLOW METER The present invention relates to a fluid flow meter and methods for measuring different aspects of fluid flow with a non-contact sensor. In some cases, a gear fluid flow meter is provided with a fluid chamber that is sealed with a cover portion carrying the non-contact sensor. An optional separating member can be located between the cover portion and the chamber to seal the chamber. In some cases the cover portion and / or separation member are configured to transmit visible light to allow visualization of the fluid chamber, through the selection of the material and / or the presence of the viewing cavities within the material. The flow meter is optionally configured to prevent or reduce the transmission of ambient radiation within the flow meter to reduce the likelihood that it will adversely affect an optical non-contact sensor used to detect the movement of gears within the chamber.
    公开号:BR112013001236B1
    申请号:R112013001236-6
    申请日:2011-08-01
    公开日:2020-12-29
    发明作者:Anatoly Skirda；Richard Mehus；William M. Christensen；Scott Limback
    申请人:Ecolab Usa Inc；
    IPC主号:
    专利说明:

    Field of the Invention
    [001] The present invention relates to a positive displacement fluid flow meter. More specifically, the present invention relates to a gear flow meter that incorporates a non-contact sensor and methods of using said devices. Background
    [002] Positive displacement fluid measurement systems can be used to measure a fluid flow coefficient or volume. For example, dispensing systems can use feedback from a positive displacement fluid meter to control the volume of fluid dispensed. These control systems can be used in place of time controls to more precisely dispense precise amounts of fluid.
    [003] One type of positive displacement fluid measurement system is a gear flow meter, for example, an oval gear or a lobe meter. A traditional oval gear meter provides a pair of oval gears positioned within an oval gear chamber so that the gears rotate accordingly. A lobe meter provides a pair of lobe elements within the chamber that interlock and rotate on the respective axes. In each case, fluid enters the chamber through a fluid inlet and causes the gears to rotate, allowing fluid to pass around the gears to the fluid outlet into precisely measured pockets. In an oval gear gauge, pockets are defined between the rotating oval gears and the inner chamber wall. On a wolf meter, the spaces between the wolves provide the pockets. Ideally, in each case, none of the fluid being measured passes directly between the gears themselves, so that the volume of fluid that leaves the chamber during each rotation is known. Thus the volume of fluid flowing through a gear gauge can be measured by measuring the number of rotations of the gears. Likewise, the flow coefficient can be determined from the speed with which the gears rotate.
    [004] To measure gear rotation, gear gauges often include additional gears. For example, an oval gear meter may include gear timing control systems located outside the chamber to translate the number of rotations of the oval gears into an appropriate signal. Oval gear and other positive displacement flow meters using gear time control systems generally have a gear chamber that includes one or more shaft openings for the shafts by coupling the gears to the external time control gears. Using the latest developments, some gear meters instead use a non-contact sensor disposed outside a substantially sealed chamber to determine the movement of the gear within the chamber. For example, magnetic and optical sensors have been incorporated into the gear flow meters to measure the movement of the gear without the need for passages or openings inside the gear chamber.
    [005] Gear fluid flow meters are used in a variety of applications where it is desirable to measure the flow of small volumes of fluids. Thus, gear gauges can be exposed to different types of fluids, require different measurement capabilities, and be arranged in different environmental conditions depending on the particular application. Gear gauges can also employ one or more of the variety of measurement technologies. Therefore, the configuration of the fluid flow meter must consider a large number of conditions that change between different applications. summary
    [006] Modalities of the present invention provide devices and methods for measuring different aspects of fluid flow, such as a flow volume, direction, and / or flow coefficient.
    [007] According to one aspect of the present invention, an embodiment of the present invention provides a flow meter for measuring fluid. The flow meter includes a housing that defines a chamber with a fluid inlet and a fluid outlet. The housing also has a cover portion and a separating member positioned between the cover portion and the chamber. The separating member has a continuous internal surface that provides the chamber wall. The flow meter also includes two gears installed inside the chamber that are rotatable on axes of rotation in response to the flow of fluid through the chamber. The flow meter also includes a non-contact sensor that is carried by the cover portion and located outside the chamber. The non-contact sensor is configured to detect the movement of at least one of the gears.
    [008] In accordance with another aspect of the present invention, a flow meter is provided for measuring fluid. The flow meter includes a housing that defines the chamber with a fluid inlet and a fluid outlet. Installed inside the chamber are first and second gears that are rotatable on the respective first and second axes of rotation in response to fluid flow through the chamber. A non-contact sensor that is configured to detect the movement of at least one of the first and second gears is located outside the chamber. The housing includes a cover portion with an outer surface and an inner surface that forms the wall of the chamber. The cover portion includes a cavity that extends within the cover portion from the outer surface, but not through the inner surface. The cavity allows the first and second gears to be discerned through the cover portion from outside the housing.
    [009] According to another aspect of the present invention, one embodiment provides a flow meter for measuring fluid that includes a housing, first and second gears, an optical sensor, and an optical filter. The housing includes a base portion that defines a chamber with a fluid inlet and a fluid outlet. The housing also includes a separating member adjacent to the base portion which includes a continuous inner surface forming the chamber wall. In addition, the housing includes a cover portion adjacent an external surface of the separating member. The first and second gears are installed inside the chamber and are rotatable on the respective first and second axes of rotation in response to the flow of fluid through the chamber. The cover portion carries the optical sensor, which includes an emitter configured to emit radiation in a wavelength range of the sensor and a detector configured to detect radiation in the wavelength range of the sensor. At least a portion of the separation member is substantially transparent to the wavelength range of the sensor to allow radiation from the sensor wavelength to pass through the separation member. The optical filter includes a material that is substantially opaque to the sensor's wavelength range. The optical filter is positioned to limit radiation within the sensor's wavelength range from the chamber entrance from outside the flow meter. In addition, the separating member includes a first material and the cover portion includes a different second material from the first material. The separating member and the covering portion transmit a sufficient amount of visible light so that the first and second gears are discernible through the covering portion and the separating member.
    [0010] In accordance with another aspect of the present invention, a method for measuring a fluid is provided. The method includes providing a flow meter provided with a chamber in fluid communication with a fluid source. The flow meter includes an optical sensor outside the chamber. The chamber includes a fluid inlet, a fluid outlet, first and second gears, and a wall with at least the portion of the wall being substantially transparent over a wavelength range of the sensor. The method additionally includes dispensing the fluid through the chamber, thereby causing the first and second gears to rotate as the fluid passes through the chamber from the fluid inlet to the fluid outlet. The method also includes reducing transmission from outside the flow meter into the radiation chamber in the sensor's wavelength range, emitting radiation in the sensor's wavelength range into the chamber with the optical sensor, and detecting radiation in the wavelength range of the sensor from the camera with the optical sensor. Rotation of the first and / or second gear is measured based on the detected radiation, and a fluid measurement is calculated based on the measured rotation.
    [0011] Some embodiments of the present invention may provide one or more of the following additional features and / or advantages. Certain modalities employ an optical sensor that measures the rotation of one or more gears. In some cases, an optical filter is provided to filter ambient radiation from the surrounding environment. This capability can improve the performance of the optical sensor. The optical filter is in some cases located on an external surface of the flow meter housing, but it can also or instead of being located on an internal surface. For example, in some cases the optical filter is located in a separating member that forms the wall of the chamber housing.
    [0012] Certain modalities provide a gear meter that can be modified depending on the contemplated application. For example, in certain cases, a flow meter is provided with a removable or interchangeable separating member. The separating member can form a wall of the fluid chamber and in some cases separates the fluid chamber from a non-contact sensor adapted to measure the rotation of one or more gears within the fluid chamber. In some cases, an external cover portion secures the separation member to the housing. In said cases the composition of the separating member can be selected to achieve a desired compatibility with a particular fluid flowing through the chamber without necessarily requiring certain physical characteristics that can, instead, be provided by the outer covering portion. In some cases a separation member currently in use can be replaced by one in a series of interchangeable separation members. Said capacity can be useful, for example, to replace a degraded or worn part, or to adapt the flow meter for a different application.
    [0013] Certain modalities of the present invention allow the direct visualization of one or more gears of the meter from outside the meter housing. Said capability can be useful, for example, to allow a visual inspection of the operation of the device and / or to confirm information from the sensors. In some cases the material for a fluid flow meter housing is chosen so as to at least allow an operator to discern the movement of the gear meters within the chamber. For example, one or more parts of the meter housing can be formed from a translucent or transparent material. In some cases visibility is increased by one or more cavities in the cover portion of the meter, which provides a thinner section of material to see through.
    [0014] The referred and several other characteristics and advantages will become apparent from the reading of the detailed description below. Brief Description of Drawings
    [0015] The following drawings are illustrative of particular embodiments of the present invention and, therefore, do not limit the scope of the present invention. The drawings are not to scale (unless otherwise stated) and are intended for use in conjunction with the explanations in the detailed description below. The modalities of the present invention will hereinafter be described in conjunction with the accompanying drawings, in which similar numbers denote similar elements.
    [0016] Figure 1 is an exploded perspective view of a flow meter according to an embodiment of the present invention.
    [0017] Figure 2 is a side view in cross section of the flow meter in Figure 1.
    [0018] Figure 3 is a graph of transmission versus wavelength for various materials useful in embodiments of the present invention.
    [0019] Figure 4A is a side view in cross section of a flow meter including an optical filter according to an embodiment of the present invention.
    [0020] Figure 4B is a cross-sectional perspective view of a flow meter including an optical filter according to an embodiment of the present invention.
    [0021] Figure 4C is a perspective cross-sectional view of a separating member including an optical filter according to an embodiment of the present invention.
    [0022] Figure 5 is a side view in cross section of a cover portion including an optical filter according to an embodiment of the present invention.
    [0023] Figure 6 is a graph of transmission versus wavelength for an optical filter useful in embodiments of the present invention.
    [0024] Figure 7 is a perspective view of a flow meter according to an embodiment of the present invention.
    [0025] Figure 8A is a perspective view of a cover portion according to an embodiment of the present invention.
    [0026] Figure 8B is a top view of the cover portion of Figure 8A.
    [0027] Figure 8C is a side view in cross section of the cover portion of Figure 8A. Detailed Description of Preferred Modalities
    [0028] The following detailed description is of an exemplary nature and is not intended to limit the scope, applicability, or configuration of the present invention in any way. Instead, the following description provides some practical illustrations for implementing examples of embodiments of the present invention. Examples of constructions, materials, dimensions, and manufacturing processes are provided for the selected elements, and all other elements employ what is known to those skilled in the art of the present invention. Those skilled in the art will note that many of the examples observed have a variety of suitable alternatives.
    [0029] The term "fluid" is used here to identify any continuous substance that tends to flow or conform to the design of its container. For example, the term fluid encompasses liquids and gases. An application of the modalities of the present invention is for liquids such as liquid products and chemicals used in cleaning, washing, disinfecting, rinsing or the like.
    [0030] Figure 1 is an exploded perspective view of a flow meter 100 according to an embodiment of the present invention. Figure 2 provides a side cross-sectional view of flow meter 100. As shown in the figures, in said embodiment of the present invention the flow meter 100 has a housing that includes a base portion 102 and a cover portion 104. A base portion defines a fluid flow chamber 106 which includes a fluid inlet 108 and a fluid outlet 110. The first and second gears 112, 114 are mounted within the chamber 106 and rotate on respective first and second axes of rotation in response to fluid flowing through chamber 106.
    [0031] The housing also includes a separating member 120 which is positioned adjacent to the base portion 102. The separating member 120 includes a continuous inner surface 128 that forms the wall of the chamber 106. The separating member 120 is positioned between the cover portion 104 and the chamber / base portion. Cover portion 104 is attached to base portion 102 using a series of fasteners such as screws or pins (not shown). Two sealing members 122 (for example, elastomeric O-rings) fit against the inner and outer surfaces 126 of the separation member, between the base portion and the separation member and the cover portion and the separation member, respectively, to additionally seal fluid chamber 106 from cover portion 104. Although not shown in figures 1 and 2, flow meter 100 also includes a non-contact sensor (for example, an optical or magnetic sensor) configured to detect the movement of one or more of the gears. In said example, the non-contact sensor is carried within a cavity 124 of the cover portion 104, outside the fluid flow chamber 106.
    [0032] In general, flow meter 100 can be coupled within a fluid flow stream to quantify one or more fluid flow characteristics. As the fluid enters the chamber 106, the gears 112, 114 (in the said example oval gears) rotate and extend and capture a precise volume, or pocket, of the fluid against an inner wall of the chamber. Because the chamber wall coincides with the arc of the largest apex of the gears through its rotation, the said fluid pocket is captured between the wall of the chamber and the surface of the gear along the minor axis of the gear and rotated from the inlet. fluid 108 to fluid outlet 110. Additionally, because the oval gears 112, 114 are in contact throughout their rotation, no fluid passes between the gears. Thus, by this action, the volume of fluid flowing through the fluid outlet is measured according to the known pocket volume. Features such as total volume, flow coefficient, and flow direction can then be measured based on the rotation of the gears as the pockets are filled and emptied.
    [0033] Each oval gear 112, 114 generally comprises a rigid material such as plastic or metal. Because the gears come into contact with the measured fluid, the choice of gear material may depend on the fluid being measured. A possible consideration may include the durability of the gear material with respect to corrosive fluids. For example, with high-concentration detergents, disinfectants, or rinsing aids, the gears may comprise machined or molded plastic such as Poly-Ether-Ether-Ketone (PEEK) on a ceramic axis. Other potential gear materials include crystallized plastics such as ULTEM, which have high durability, high temperature tolerance, low thermal expansion, low moisture absorption, and are chemically inert. Additional materials may include RYTON and metals such as 316 SS.
    [0034] Of course, a wide variety of gears can be used in different embodiments of the present invention. The selection of gear settings may depend on the properties of the fluid being measured. For example, a high-viscosity fluid is less likely to slip between drive gears, so smooth gears may be appropriate. Differently, low viscosity and / or high lubricity fluids may require the use of mesh gears. In addition, although the specific modalities described here are discussed mainly with respect to flow meters incorporating oval shaped gears, the present invention is not limited to said modalities. Those skilled in the art can observe that the present invention can be practiced with a variety of positive displacements based on flow meters. The modalities of the present invention are readily adaptable by those skilled in the art to any positive displacement flow meter that operates to send discrete pockets of fluid by rotation of a flow meter element. For example, a wolf gauge, which is a positive displacement flow meter that uses interlocking wolf-shaped gear gauge elements to pass pockets of fixed volume fluid through the chamber, can be adapted according to the modalities of the present invention.
    [0035] Several types of non-contact sensors can be incorporated inside the flow meter 100 for reading the movement of the gears 112, 114 from outside the fluid chamber 106. For example, in some cases one or more of the gears they include a permanent magnet (ie, the "trigger gear") and the non-contact sensor is a magnetic sensor (ie, magneto-reactive). An example of a suitable magnetic sensor is described in US patent application No. Commonly assigned No. 7,523,660, the total content of which is incorporated herein by reference. As the trigger gear rotates in response to fluid flow, the magnetic field generated by the permanent magnet also rotates. A magnetic sensor such as a GMR sensor (giant magnet resistance effect sensor) reads the rotation of the magnetic field and generates a corresponding output signal. Thus the movement of the gears and the corresponding fluid flow can be quantified. One or more GMR sensor elements can be used to monitor the rotation of the trigger wheel. An example of a suitable GMR sensor is a GMR swing valve sensor offered by NVE Corporation with identification number NVE AAV 001-11 and AAV 002-11. This is, of course, a brief overview of the operation of said magnetic sensor and those skilled in the art will note that a number of details are omitted here for the sake of clarity. In addition, other types of magnetic sensors known in the art can also be employed with the flow meter 100.
    [0036] In some embodiments, the non-contact sensor is provided as an optical sensor. An example of a suitable non-contact optical sensor is described in US patent application No. commonly assigned serial number 12 / 369,501, filed on February 11, 2009, the entire contents of which are hereby incorporated by reference. In some cases at least the portion of the separation member 120 is substantially transparent to a wavelength range of the sensor used by an optical sensor positioned adjacent an external surface 126 of the separation member, providing a view of the rotating gears through the member of separation 120. The optical sensor can see an optical characteristic of one or both gears, and based on said data, fluid volume, flow coefficient, and / or flow direction can be determined.
    [0037] The optical sensor can be any sensor capable of detecting the optical property of the gears used to determine the rotational position of the gears. Sensors adapted to measure in general any optical property can be used including, for example, reflectance or transmission. In some preferred embodiments, the optical property is reflectance. Reflectance can be measured by an optical sensor including an emitter, which emits light energy in one or a range of wavelengths and a detector that is positioned to receive reflected light from all or a portion of the emitted wavelength range. The light energy can be electromagnetic radiation in general of any wavelength, for example, UV, visible, infrared and other light can be used. In some preferred embodiments, infrared light can be used. For example, in some embodiments, reflectance is measured with a 940 nm QRB 1114 offered by Fairchild Semiconductor International, Inc. Other suitable reflective sensors include a 950 nm EE-SY125 sensor, a 920 nm EE-SY310 / SY410 sensor sensor, and a 940 nm EE-SY171 sensor, all offered by Omron Electronic Components LLC. Other suitable reflective sensors include an OPB609GU sensor offered by OPTEC, a QRE1113GR sensor offered by Fairchild Semiconductor, and a CNBIOOI sensor offered by Panasonic. In principle, higher resolution sensors can be achieved with shorter wavelengths and more focused light energy. Using an ultraviolet (UV) and / or laser emitter, you can provide that enhanced resolution.
    [0038] In cases where an optical sensor is employed, one or more of the gears 112, 114 can include a distinct optical characteristic capable of being seen by the sensor through the separating member 120. For example, the distinct optical characteristic can be located on the top surface of the gears, adjacent to an internal surface 128 of the separation member 120. The distinct optical characteristic can be any indication that results in the optical sensor registering a different reading from when the characteristic is not seen. For example, the top surface of each gear may have a different optical reflectance pattern at the sensor's wavelength due to the use of different colors, materials of different reflectivity, or the use of one or more different points on the surface of the sensor. (s) gear (s).
    [0039] For embodiments employing an optical sensor, the separating member 120 preferably comprises a material that is substantially transparent to radiation within the wavelength range of the sensor. For example, in some cases the entire separating member 120 may be substantially transparent in the wavelength range of the sensor. In certain embodiments, only the portion of the separating member 120 (e.g., a window or lens) can be substantially transparent in the wavelength range of the sensor. The separation member 120, optical sensor, and gears / chamber are preferably aligned to provide the optical sensor with an unobstructed view of at least part of the gears through the portion of the separation member substantially transparent to the sensor wavelength range. The sensor wavelength range includes wavelengths of radiation transmitted by the sensor emitter and detected by the sensor detector. For example, an optical sensor that operates in a sensor wavelength range including near-infrared radiation can use wavelengths ranging from about 700 nm to about 1100 nm or more. Of course, it will be noted that other wavelength bands can also be used.
    [0040] The term "substantially transparent" is used here to describe a material for the separation member 120 that allows the transmission of radiation into and out of the fluid chamber 106 to a sufficient degree so that the optical sensor is able to properly detect the movement of the gears based on the emitted and reflected radiation. Therefore, the material does not need to transmit all or almost all radiation within the sensor's wavelength range, although in some cases it may approach this limit. In certain applications a material with a lower transmission coefficient may be sufficient to allow adequate performance of the sensor, and said material is considered to be substantially transparent in the wavelength range of the sensor for the purposes of the present description.
    [0041] Figure 3 is a graph 300 showing the transmission characteristics of various materials that can be useful for separation member 120 when the sensor's wavelength range is between about 700 nm and about 1100 nm or more . Most materials exhibit a transmission of at least 50% in that range, a few at least 60%, and others at least 80%. Examples of materials that may be suitable for transmitting radiation in the range 700 nm to 1100 nm include glass, sapphire, borosilicate, polymethylpentene, polysulfone, polyetherimide, polypropylene, polycarbonate, polyester, PVC and acrylic glass. Of course, varying levels of transmission may be necessary or permitted due to the performance characteristics of the optical sensor, and it is possible that even lower transmission ranges may be sufficient for extremely sensitive optical sensors and higher transmission ranges may be necessary for less effective sensors.
    [0042] The separating member 120 can be formed from a series of materials depending on one or more configuration factors for a particular modality. Just as a few examples, some criteria that may affect the choice of material for separation member 120 include the particular fluid that passes through the chamber 106, the fluid flow pressure, cost factors, and / or, in cases using a optical sensor, transparency criteria for the optical sensor wavelength range. For example, separation member 120 must be produced from one or more materials that are compatible and sufficiently chemically inert with respect to fluids flowing through the chamber. For applications involving chemicals with a high pH content, a low pH content or strong oxidizers, the separation member 120 can, for example, be produced from a very inert material such as clear sapphire or grade borosilicate commercial. An example of a commercially available material is Borofloat, offered by Precision Glass and Optics. In some cases the separating member may be formed solely or partially from one or more of the materials noted above, including glass, sapphire, borosilicate, polymethylpentene, polysulfone, polyetherimide, polypropylene, polycarbonate, polyester, PVC and acrylic glass. Other materials known in the art can also be used.
    [0043] The design of the separating member 120 may also vary depending on the application. Factors that affect the thickness of the separation member 120 can include the pressure of the fluid flowing through the chamber, the inherent resistance of the material itself, and the support provided by the cover portion 104 that secures the separation member 120 in the base portion 102 In some cases, for example, the separating member 120 is a plate having a thickness of less than about 15 millimeters. In certain embodiments the thickness is between about 1 millimeter and about 2 millimeters. Of course, it will be noted that other thicknesses may be appropriate depending on the transmission of the material, the strength of the material and other factors.
    [0044] Returning to figures 1 and 2, the cover portion 104 is attached to the base portion 102 and encapsulates the separation member 120 between the cover portion and the base portion. Thus the cover portion 104 provides a structural housing on the separation member, fixing the separation member against the base portion 102 and the chamber 106 without the need to directly fix the separation member to the base portion (for example, with screws, pins, etc.). The cover portion 104 can be formed from the same material as the separating member or a different material. For example, a cover portion 104 may comprise a material such as glass, sapphire, borosilicate, and / or acrylic glass. In some cases the cover portion 104 is formed from a moldable plastic material such as polymethylpentene, polysulfone, polyetherimide, polypropylene, polycarbonate, polyester and / or PVC.
    [0045] In some cases the cover portion 104 preferably provides a strong structural housing over the separation member, allowing the separation member to be formed from different materials that may be weaker or more brittle, for example. The separation member 120 provides a separate seal for the fluid flow chamber 106, thereby preventing fluids from flowing through the chamber from the contact cover portion 104. Therefore, the cover portion and the separation member can be formed from different materials. For example, the separating member can comprise a material that is compatible with the fluids flowing through the chamber, while the cover portion 104 can comprise a material that is structurally strong, although not necessarily compatible with the fluids. In some cases, for example, the separating member is formed from a first material that is more resistant to fluids flowing through the chamber than a second material used to form the cover portion.
    [0046] In some cases the cover portion 104 is removably coupled to the base portion with, for example, screws, pins, or other removable fixing means. Thus, the cover portion 104 can be removed from the base portion 102 to provide access to the separation member 120. This can be useful for cleaning or replacing the separation member. In some cases the flow meter 100 can be adapted to handle different fluids by removing a separating member and replacing it with another separating member without the need to replace the entire cover portion 104. For example, a separating member can be exchanged for one with a more desirable operating capacity (eg chemical resistance, pressure resistance, etc.) suitable for the particular application. Thus, the use of a distinct covering portion from the separation member provides a degree of adaptability or interchangeability with respect to the separation member. It should be appreciated, however, that the cover portion need not be removable in all cases, and can instead be permanently attached to the base portion on the separation member (for example, with an adhesive, screws, pins, etc.).
    [0047] The separating member 120 and the cover portion 104 may also exhibit a degree of visible transparency in some embodiments to allow an operator to visually observe the operation of the flow meter 100. For example, the cover portion 104 and the separation member 120 can be formed from a material that transmits a sufficient amount of visible light so that the first and / or second gears are discernible through the cover portion and the separation member. In some cases the cover portion and the separating member are substantially transparent to visible light, although minor degrees of transparency (eg translucency) may also be sufficient in some cases to allow at least one person to discern the movements of the gears . For example, graph 300 in Figure 3 illustrates the transparency of a series of materials that have between about 20% and about 90% transmission in the visible range, from 400 nm to 700 nm, depending on the nature and thickness of the material . In some cases the entire covering portion 104 and / or the separating member 120 may be formed from said material, although it is also contemplated that the covering portion and / or the separating member may include a small transparent portion of the whole (for example, a window) to allow a person to inspect the operation of the gears.
    [0048] Figures 4A and 4B are side and perspective views of a flow meter 400 according to an embodiment of the present invention. Flow meter 400 is similar in many respects to flow meter 100 described with reference to Figures 1 and 2, but Figure 4A also illustrates an optical sensor 402 positioned within cavity 124 of the cover portion 104. Optical sensor 402 is adapted to detect the movement of at least one of the gears 112, 114 by emitting and detecting light in a wavelength range of the sensor in the manner previously described. Flow meter 400 also includes an optical filter 404 positioned to limit radiation entry within the sensor wavelength range into chamber 106 from outside flow meter 400 or prevent it from otherwise interfering with sensor operation optical 402.
    [0049] The optical filter 404 includes a material that is substantially opaque to the sensor's wavelength range and thus selected to block ambient radiation within the sensor's wavelength range. In some cases it is an optical interference filter or an absorption filter. The filter does not need to block all ambient radiation in the sensor's wavelength range, although it may approach that limit in some cases. For example, in some cases the optical filter 404 may filter or transmit a sufficiently low amount of ambient radiation of the sensor's wavelength so that it does not affect the measurements made by the optical sensor 402. The degree of filtration required may change depending on the properties reflectance of the various materials in the flow meter 400 as well as the sensitivity and settings of the optical sensor 402 and associated circuits.
    [0050] Figure 6 is a graph 600 illustrating the degree of filtration offered for an example of a commercially offered filter material called Super HeatBuster Hot Mirror, offered by Deposition Sciences Inc. As shown in graph 600, a 602 sensitivity range for the ranges of photoreflective QRE1113 sensors between about 700 nm and about 1100 nm (ie, infrared radiation in the illustrated mode). The optical filter transmits a minimal response to the infrared wavelengths for both ambient radiation at zero degrees 604 as well as for radiation 606 entering at an angle of about 40 degrees. Said optical filter can be useful to limit the effect of ambient infrared radiation on adjustments with, for example, intense incandescent light or sunlight.
    [0051] As shown in figures 4A-4C, in some cases the optical filter 404 is part of the separation member 120 or deposited directly on the external surface of the separation member 120. In this case, the optical filter 404 is positioned between the chamber 106 and optical sensor 402. To prevent the desired blocking of radiation from the sensor's wavelength from being transmitted to and / or from the sensor, the portion of the separating member 120 may have a viewing port 410 for the optical sensor 402 for look into chamber 106. For example, a central section of separation member 120 may have the optical filter medium masked or physically removed to create the viewing port 410. In some cases the optical filter comprises a thin layer deposited on the separation member although other configurations are possible.
    [0052] Returning to figure 5, in some cases an optical filter 500 is positioned adjacent an external surface of the cover portion 104. For example, the filter 500 can be a thin layer deposited on the cover portion. Thus, the cover portion 104 itself provides some shields against ambient radiation within the wavelength range of the sensor without the need to incorporate the optical filter into the separation member 120. This can help to reduce costs where different types of separation members (for example, as discussed above) can be designed and manufactured without the need for an optical filter on each separation member. Instead of the optical filter 500 being applied once to the outside of the cover portion 104. Of course, it should be appreciated that other positions for the optical filter are possible and that these are just examples of some suitable locations.
    [0053] In some cases the optical filter selectively blocks (for example, reflects and / or absorbs) radiation within the sensor's wavelength range while also transmitting radiation within the visible wavelength range. As shown in Figure 6, for example, the optical filter blocks radiation within the range of about 700 nm to about 1100 nm (the sensitivity region for the optical sensor) but also substantially transmits visible radiation within the length range of 400 nm to 700 nm wave depending relatively on the viewing angle. Accordingly, said optical filter can be combined with a separating member and cover portion which also exhibits a visible degree of transparency to allow an operator to visually observe the operation of the flow meter 100, while also reducing the impact of ambient radiation within the sensor's wavelength range.
    [0054] Figure 7 is a perspective view of a flow meter 700 according to an embodiment of the present invention. Figure 7 illustrates a cover portion 704 of flow meter 700 in partial cross section. The flow meter 700 includes a housing 701 that defines the chamber 706 provided with a fluid inlet and a fluid outlet. The housing 701 includes a base portion 702 and a cover portion 704 mounted on the base portion 702 with a fastener such as, for example, screws or pins (now shown). The cover portion 704 has a continuous inner surface that forms the wall of the chamber 706. The cover portion also has an outer surface 708 opposite the inner surface. The first and second gears 712, 714 are rotationally installed inside the chamber 706 on the axes of rotation and rotate in response to the fluid flowing through the chamber 706. Although not shown, the flow meter 700 generally includes a non-contact sensor located outside the chamber 706 and configured to detect the movement of at least one of the gears within the chamber. For example, the non-contact sensor can be mounted inside a cavity sensor 720 within the cover portion 704.
    [0055] As shown in Figure 7, in some embodiments the cover portion 704 directly attaches to the base portion 702 and provides a wall of the chamber 706 without the use of a separate separation member as described with respect to other embodiments of the present invention. An elastomeric O-ring or other sealing mechanism (not shown) can increase the seal between the base and cover portions. As shown in figures 7 and 8A-8C, the cavity sensor 720 of the cover portion 704 extends within the cover portion from its outer surface 708, but does not extend through the cover portion so as to leave the inner surface 722 of the intact cover portion, thus providing a continuous surface or wall that seals one side of the chamber 706.
    [0056] The cover portion 704 is preferably formed from a material that is compatible not only with the fluids flowing through the chamber 706 but also the non-contact sensor positioned within the cavity sensor 720. For example, the cavity wall sensor 730 should allow the non-contact sensor to properly read the movement of one or both gears 712, 714. In the case of a magnetic sensor, the wall of cavity 730 must adequately transmit magnetic fields (for example, being formed at from a non-magnetic or non-metallic material) so that the sensor can receive and feel the changes in the magnetic field caused by the movement of the gears. In the case of an optical sensor, the cavity wall 730 must substantially transmit radiation within the sensor's wavelength range so that the sensor can adequately emit and receive radiation from the sensor's wavelength. For example, in the case of an optical infrared sensor (such as one of the previously mentioned) the cavity wall 730 must be substantially transparent to the infrared wavelengths in use. In some cases, the cover portion 704 is formed from polypropylene, which is substantially transparent to radiation within the infrared wavelength range.
    [0057] Additionally, the sensor cavity wall 730, along the entire inner surface 722 of the cover portion, must be compatible with fluids flowing through the chamber 706. For example, the inner surface of the cover portion 704 should be produced from one or more materials that are sufficiently chemically inert with respect to fluids flowing through the chamber. This can be useful for a number of applications, including those involving chemicals with a high pH, low pH or strong oxidizers. A range of materials can be selected for the coverage portion depending on the desired fluid resistance and the desired compatibility with the non-contact sensor. Just as an example, the cover portion 704 can be formed from polypropylene when the non-contact sensor is an optical sensor that operates in the infrared range and liquid chemicals are particular types of laundry detergents. In some cases an optical filter, such as that discussed with reference to Figure 5, is also included to block ambient light that can affect the performance of an optical sensor.
    [0058] The cover portion 704 may also exhibit a degree of visible transparency in some embodiments to allow an operator to visually observe the operation of the flow meter 700. For example, the cover portion 704 may include a material that transmits sufficient amount of visible light so that the first and / or second gears are discernible through the cover portion. In some cases it is preferable that the cover portion 704 provides a structurally strong component housing the flow meter 701, while also being resistant (for example, inert) to chemicals flowing through the chamber, as well as visibly transparent to allow an operator to observe the movement of the gears.
    [0059] As shown in figures 7 and 8A-8C, in some embodiments the cover portion includes one or more viewing cavities 750, which allows one or both gears to be discerned within chamber 706. Cavities 750 extend within the covering portion 704 from the outer surface 708, but do not extend across the inner surface 722. The cavities thus form a thin viewing wall 752 adjacent to the inner surface of the covering portion 704. Said thin walls 752 can provide a degree of transparency that allows the first and / or second gears to be discerned through the cover portion from outside the housing 701. For example, a normally translucent material such as polypropylene can normally obscure the view through the thickness of the material. By forming a cavity and a sufficiently thin section in a portion of the polypropylene cover, visualization within the 706 chamber can be allowed as illustrated in Figure 7. Although Figures 7 and 8A-8C illustrate a covering portion with multiple viewing cavities 750, it should be noted that a single viewing cavity can also be used, or that a similar covering portion can be provided without the viewing cavity.
    [0060] Although not shown in the figures, in some embodiments a cover portion provided with one or more viewing cavities may be used in conjunction with a separation member such as the separation member described with reference to Figures 1 and 2. For For example, it may be desirable to form a covering portion of a non-transparent material (for example, a translucent material) for the sake of several design factors such as cost, material strength, etc. In said cases the viewing cavity can be formed by extending within the cover portion from the outer surface. In some cases the cavity may not extend across the inner surface of the cover portion, similar to the example shown in figures 7 and 8A-8C. In some cases, the cavity may extend entirely through the cover portion since the separating member is positioned between the cover portion and the base portion to seal the fluid chamber.
    [0061] Methods for measuring a fluid are also provided according to some embodiments of the present invention. In some cases, a method includes providing a flow meter, such as one described above, provided with a chamber in fluid communication with a fluid source and an optical sensor outside the chamber. The chamber includes a fluid inlet, a fluid outlet, first and second gears, and a wall with at least a portion of the wall being substantially transparent to a wavelength range of the sensor used by the optical sensor. Fluid is dispensed into the chamber, causing the first and second gears to rotate. The method includes reducing (or substantially blocking) radiation transmission in the sensor's wavelength range from outside the flow meter inside the chamber. For example, an optical filter such as one described above can be provided. In addition, the optical sensor emits radiation in the wavelength range of the sensor inside the chamber and detects the reflected radiation back from the chamber. The method additionally includes measuring the rotation of the first and / or second gear based on the detected radiation and calculating a fluid measurement based on the measured rotation. For example, the evaluation of electronics associated with the sensor can calculate a flow coefficient, flow volume and / or flow direction based on the detected radiation. In some cases the method also provides a visible view of the rotation of the first gear and / or the second gear from outside the flow meter.
    [0062] Thus, the modalities of the present invention are described. Although the present invention has been described in considerable detail with reference to certain described modalities, the described modalities are presented for the purpose of illustration and not to limit other possible modalities of the present invention. Those skilled in the art will note that various changes, adaptations, and modifications can be produced without departing from the spirit of the present invention and the scope of the appended claims.
    权利要求:
    Claims (15)
    [0001]
    1. Flow meter (100) for measuring fluid comprising: a housing defining a chamber (106) having a fluid inlet (108) and a fluid outlet (110), the housing comprising a cover portion (104) and a separation member (120) positioned between the cover portion (104) and the chamber (106), the separation member (120) comprising a continuous internal surface (128) forming a wall of the chamber (106); first and second gears (112, 114) installed inside the chamber (106), the first and second gears (112, 114) being rotatable on respective first and second axes of rotation in response to the flow of fluid through the chamber (106) ; and a non-contact sensor carried by the cover portion (104) and located outside the chamber (106), the non-contact sensor configured to detect movement of at least one of the first and second gears (112, 114); wherein the non-contact sensor is an optical sensor comprising an emitter configured to emit radiation in a wavelength range of the sensor and a detector configured to detect radiation in the wavelength range of the sensor, in which at least a portion of the separation member (120) is substantially transparent to the sensor's wavelength range; CHARACTERIZED by the fact that the separating member (120) comprises an optical filter (404) comprising a material substantially opaque to the sensor's wavelength range and substantially transparent to visible light, the optical filter (404) positioned to limit radiation within the wavelength range of the sensor entering the chamber (106) from outside the flow meter (100); and the separating member (120) and the cover portion (104) are removable.
    [0002]
    2. Flow meter according to claim 1, CHARACTERIZED by the fact that the optical filter (404) is positioned adjacent to an external surface of the cover portion (104).
    [0003]
    3. Flow meter according to claim 1 or 2, CHARACTERIZED by the fact that the sensor's wavelength range comprises infrared radiation.
    [0004]
    Flow meter according to any one of claims 1 to 3, CHARACTERIZED by the fact that the optical filter (404) comprises a film.
    [0005]
    Flow meter according to any one of claims 1 to 4, CHARACTERIZED in that the separating member (120) comprises a first material and the cover portion (104) comprises a second material different from the first material.
    [0006]
    Flow meter according to any one of claims 1 to 5, CHARACTERIZED by the fact that the first material is more resistant to fluids flowing through the chamber (106) than the second material.
    [0007]
    Flow meter according to any one of claims 1 to 6, CHARACTERIZED by the fact that the separating member (120) and the covering portion (104) transmit a sufficient amount of visible light so that the first gear (112) and / or the second gear (114) is (are) discernible through the cover portion (104) and the separating member (120).
    [0008]
    Flow meter according to any one of claims 1 to 7, CHARACTERIZED by the fact that the first material and the second material are substantially transparent to visible light.
    [0009]
    Flow meter according to any one of claims 1 to 8, CHARACTERIZED by the fact that the first material and the second material are selected from the group consisting of glass, sapphire, borosilicate, polymethylpentene, polysulfone, polyetherimide, polypropylene, polycarbonate, polyester, PVC and acrylic glass.
    [0010]
    Flow meter according to any one of claims 1 to 9, CHARACTERIZED by the fact that the second material is non-transparent and the cover portion (104) comprises at least one cavity (124) extending within the portion cover (104).
    [0011]
    Flow meter according to any one of claims 1 to 10, CHARACTERIZED by the fact that the at least one cavity (124) extends entirely through the cover portion (104).
    [0012]
    Flow meter according to any one of claims 1 to 11, CHARACTERIZED in that the separating member (120) comprises a plate having a thickness of less than about 15 millimeters.
    [0013]
    13. Flow meter according to claim 12, CHARACTERIZED by the fact that the thickness is between about 1 millimeter and about 2 millimeters.
    [0014]
    Flow meter according to any one of claims 1 to 13, CHARACTERIZED by the fact that the separating member (120) and the cover portion (104) are removable.
    [0015]
    15. Flow meter according to any one of claims 1 to 14, CHARACTERIZED by the fact that the non-contact sensor is a magnetic sensor.
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    同族专利:
    公开号 | 公开日
    ES2727029T3|2019-10-11|
    US8166828B2|2012-05-01|
    AU2011287261B2|2014-12-18|
    CN106017591A|2016-10-12|
    MX2013001231A|2013-03-12|
    CA2803251C|2019-02-05|
    JP2013532837A|2013-08-19|
    EP2601488A4|2016-11-09|
    NZ604799A|2015-03-27|
    CN103052867A|2013-04-17|
    CN103052867B|2016-06-29|
    BR112013001236A2|2016-05-17|
    EP2601488A2|2013-06-12|
    CA2803251A1|2012-02-09|
    EP2601488B1|2019-05-01|
    AU2011287261A1|2013-01-10|
    US20120031195A1|2012-02-09|
    WO2012017380A2|2012-02-09|
    WO2012017380A3|2012-06-07|
    CN106017591B|2019-09-27|
    JP6126001B2|2017-05-10|
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    法律状态:
    2018-12-26| B06F| Objections, documents and/or translations needed after an examination request according [chapter 6.6 patent gazette]|
    2019-08-13| B06U| Preliminary requirement: requests with searches performed by other patent offices: procedure suspended [chapter 6.21 patent gazette]|
    2020-03-10| B06A| Patent application procedure suspended [chapter 6.1 patent gazette]|
    2020-10-13| B09A| Decision: intention to grant [chapter 9.1 patent gazette]|
    2020-12-29| B16A| Patent or certificate of addition of invention granted [chapter 16.1 patent gazette]|Free format text: PRAZO DE VALIDADE: 20 (VINTE) ANOS CONTADOS A PARTIR DE 01/08/2011, OBSERVADAS AS CONDICOES LEGAIS. |
    优先权:
    申请号 | 申请日 | 专利标题
    US12/851,598|US8166828B2|2010-08-06|2010-08-06|Fluid flow meter|
    US12/851,598|2010-08-06|
    PCT/IB2011/053423|WO2012017380A2|2010-08-06|2011-08-01|Fluid flow meter|
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