The present invention generally relates to the field of collecting and measuring rainfall and other precipitation with a self-emptying precipitation gauge. More specifically, embodiments of the present invention are directed to a precipitation gauge apparatus for measuring rainfall based on weight as the rain is collected.
Instruments and apparatus systems that are used for collecting and measuring rainfall and the rate of rainfall often require a receiving bucket or cup oriented toward the sky that collects rainfall and other precipitation. For such known instrumentation, concerns for properly measuring and analyzing the collected rainfall and precipitation include the size of the receiving vessel, sensitivity of any coupled sensor, and consistent drainage of collected rain water or other precipitation. Typically, in known rainfall gauge devices, some of which are referred to as “tipping” gauges, a rainfall collector includes a bucket, spoon, or cup apparatus that accumulates a volume of rainwater and then tips, signaling that a known amount of rain has fallen. However, in such instrumentation, errors may be generated simply due to the physical construction and operation of the rain gauge.
Accordingly, there remains a need to provide rain gauge instrumentation that accurately measures rainfall without errors associated with the physical construction and operation of tipping bucket rain gauges known in the field.
The following presents a simplified summary of some embodiments of the invention in order to provide a basic understanding of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key or critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some embodiments of the invention in a simplified form as a prelude to the more detailed description that is presented later.
Embodiments of the invention are directed toward a precipitation gauge that includes a base assembly; a base adaptor coupled to the base assembly; a collection vessel having a collection arm and a counterweight arm configured to receive fluid in the collection arm, mounted to the base adaptor via a pivot rod, and operable between a collection and measurement position and a fluid discharge position; a magnet located on the collection arm; an armature configured to magnetically couple to the magnet and hold the collection vessel in the collection and measurement position; and a load cell electrically coupled to the armature and configured to transmit signals corresponding to tension on the armature. The precipitation gauge collection arm can be configured to collect fluid where the collection vessel is oriented at the collection and measurement position, where an increase in weight of the collection vessel due to the collected fluid increases tension on the armature. The weight of the collection arm and fluid held in the collection arm can exerts a torque around the pivot rod greater than the combination of an opposing torque the counterweight arm exerts around the pivot rod and an attractive force of the magnetic coupling between the armature and magnet, such that the collection vessel rotates around a rotational axis of the pivot rod to the fluid discharge position. In some aspects, the torque the counterweight arm exerts around the pivot rod is greater than the torque the collection arm collection arm exerts around the pivot, such that the collection vessel rotates around a rotational axis of the pivot rod to the collection and measurement position. The precipitation gauge can further include a housing above and around the base assembly and base adaptor, configured to receive precipitation and direct fluid into the collection vessel. The precipitation gauge can further include a debris filter mounted within the housing configured to prevent detritus from falling onto the precipitation gauge. The housing can have an opening configured to have a shape and area to regulate the amount of precipitation directed toward the collection vessel. The precipitation gauge can further include a non-transitory computer-readable medium (such as a microprocessor) that is electrically connected with the load cell, that is configured to receive, store, and transmit data corresponding to the signals transmitted by the load cell. The precipitation gauge load cell can transmit signals proportional to increases in tension on the armature, where the increase in tension on the armature can be generated by increases in weight due to fluid collected in the collection arm to which the armature is magnetically coupled via the magnet. Further, the precipitation gauge can be collection vessel is symmetric, such that the lever arm length of precipitation remains constant as precipitation accumulated in the collection vessel.
Embodiments of the invention are directed to a method of measuring precipitation including collecting precipitation in a collection vessel in a collection and measurement position; sensing a tensile force caused by the weight of precipitation collected with at least one load cell coupled to the collection vessel; correlating the tensile force sensed by the at least one load cell with a precipitation measurement; discharging precipitation collected in the collection vessel once a threshold volume of precipitation has been collected by pivoting the collection vessel to a fluid discharge position; and returning the collection vessel to the collection and measurement position. In some aspects of the method, correlating the tensile force sensed by at least one load cell can include sensing positive increments in weight. In other aspects of the method, correlating the tensile force sensed by at least one load cell can include not sensing negative increments in weight. Where at least one load cell is coupled to an armature, and where the armature is configured to magnetically couple with a magnet on a collection arm of the collection vessel, precipitation collected in the collection arm can increase tension on the load call via the armature magnetically coupled to the magnet. In some aspects, the collection vessel can be positioned within a housing, where the housing having an opening with a shape and an area regulating the amount of precipitation collected by the collection vessel. In other aspects of the method, at least one load cell can relay data corresponding to the weight of precipitation to a microprocessor to calculate a precipitation measurement. A counterweight arm of the collection vessel can provide torque, urging the collection vessel toward the collection and measurement position. Precipitation discharged from the collection vessel can be directed toward a drain positioned below the collection vessel. Further, after discharging precipitation, the microprocessor can re-zero the measurement of the weight of precipitation in the collection vessel.
Embodiments of the present invention are directed to a precipitation gauge including a collection vessel which is coupled to a pivot mount via a mounting shaft, mounting rod, or pivot shaft, where the collection vessel has a collection arm and a resistance arm positioned on opposing sides of the pivot mount, the collection vessel being movable between a first position and a second position, the collection vessel further having an armature counterweight mechanically coupled to the end of the resistance arm distal from the pivot mount, a force gauge capable of sensing and signaling compressive and tensile forces, and a magnet mechanically coupled to the force gauge magnetically coupled with the armature counterweight. When the collection vessel is in the first position, the collection arm receives and holds fluids that are received from above the collection vessel, and the armature counterweight is held in close proximity to, or in contact with, the magnet. As the collection arm receives and holds increasing amounts of fluid, the force gauge senses increases in weight through compressive and tensile forces transmitted from the collection arm through the receiving arm and magnet. When the weight of the fluid held by the collection arm exerts or generates sufficient or threshold torque, the magnetic coupling of the magnet and armature counterweight does not hold the magnet and armature counterweight in close proximity, and the collection vessel rotates along a rotational axis of the pivot shaft to the second position such that fluid held within the collection arm is discharged.
Further embodiments of the precipitation gauge include a collection vessel which is coupled to a gauge frame via a pivot shaft (which may be alternatively referred to as a mounting rod or mounting shaft), where the collection vessel has a collection arm and a resistance arm positioned on opposing sides of the pivot shaft, the collection vessel being movable between a first position and a second position, the collection vessel further having an armature counterweight mechanically coupled to the end of the resistance arm distal from the pivot shaft, at least one load cell capable of sensing and signaling compressive and tensile forces, and a magnet mechanically coupled to the gauge frame magnetically coupled with the armature counterweight. When the collection vessel is in the first position, the collection arm receives and holds fluids that are received from above the collection vessel, and the armature counterweight is held in close proximity to, or in contact with, the magnet. As the collection arm receives and holds increasing amounts of fluid, the at least one load cell senses increases in weight through compressive and tensile forces transmitted from the collection arm through the receiving arm and magnet. When the weight of the fluid held by the collection arm exerts or generates sufficient or threshold torque, the magnetic coupling of the magnet and armature counterweight does not hold the magnet and armature counterweight in close proximity, and the collection vessel rotates along a rotational axis of the pivot shaft to the second position such that fluid held within the collection arm is discharged
In some embodiments of the precipitation gauge, following the discharge of fluid from the collection arm, the torque exerted by the armature counterweight and magnet causes the collection vessel to rotate back to the first position. In some aspects, the magnetic attraction between the armature counterweight and magnet causes the collection vessel to rotate back to the first position. In other aspects, when the armature counterweight and magnet are in close proximity, the armature counterweight and magnet are flush and in direct contact with each other. In some embodiments, the force gauge is a cantilever beam gauge.
In some embodiments, the precipitation gauge is contained within a housing above and around the collection vessel which directs fluid into the collection vessel. In many embodiments, a debris filter is mounted within the housing configured to prevent detritus or debris from falling onto the precipitation gauge. In aspects, the precipitation gauge further includes a splash shield configured to prevent fluid collected in the collection arm from splashing onto any other element of the precipitation gauge. In many aspects, the precipitation gauge is coupled to a microprocessor, and can be electrically connected to a microprocessor via a force gauge. In other aspects, the precipitation gauge can be coupled to a microprocessor via at least one load cell.
Alternative embodiments of the precipitation gauge include a collection vessel, coupled to a gauge frame via a pivot shaft, having a collection arm and a resistance arm positioned on opposing sides of the pivot shaft, the collection vessel being movable between a first position and a second position, having a counterweight mechanically coupled to the end of the resistance arm distal from the pivot shaft, an armature positioned in proximity to the end of the collection arm distal from the pivot shaft, the armature being coupled to a force gauge, and a magnet mechanically coupled to the end of the collection arm distal from the pivot shaft, and magnetically coupled with the armature. When the collection vessel is in the first position, the collection arm receives and holds fluids that are received from above the collection vessel, and the armature is held in close proximity to, or in contact with, the magnet. As the collection arm receives and holds increasing amounts of fluid, the force gauge senses increases in weight through compressive and tensile forces transmitted from the collection arm through the magnet. When fluid held by the collection arm exerts or generates sufficient or threshold torque, the magnetic coupling of the magnet and armature does not hold the magnet and armature in close proximity, and the collection vessel rotates along a rotational axis of the pivot shaft to the second position such that fluid held within the collection arm is discharged.
Embodiments of the invention include a method of measuring precipitation rate, where the method includes collecting precipitation in a collection vessel in a collection and measurement position, sensing a compressive or tensile force caused by the weight of precipitation collected with a force gauge and/or at least one load cell coupled to the collection vessel, discharging precipitation collected in the collection vessel once a sufficient or threshold volume of precipitation has been collected by pivoting the collection vessel to a position that discharges the precipitation, and returning the collection vessel to the collection and measurement position. In aspects, the method further includes having a force gauge and/or at least one load cell configured to sense positive increments in weight. In aspects, the method further includes having a force gauge and/or at least one load cell configured to not report negative increments in weight. In embodiments, the measurement of rainfall and other precipitation as it is collected reduces errors typical to other tipping rain gauges known in the field.
These and other features, aspects, and advantages are described below with reference to the following drawings, and will become better understood when the following detailed description is read with reference to the accompanying drawings.
Throughout this description for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the many embodiments disclosed herein. It will be apparent, however, to one skilled in the art that the many embodiments may be practiced without some of these specific details. In other instances, well-known structures and devices are shown in diagram or schematic form to avoid obscuring the underlying principles of the described embodiments.
While the many embodiments disclosed herein are generally directed to the collection and measurement of rainfall and other precipitation, the weight-based measurement gauge described herein can be used for any application where the regular collection and measurement of fluids and/or fluid flow would be appropriate or advantageous. The inventor herein has recognized sources of error in known precipitation collection and measurement instrumentation. In particular, each tip of a rain collecting bucket has errors associated with (1) variation in the volume at the tipping point of the bucket, (2) incoming water that is not accounted for during the tipping of the bucket, (3) residual water that fails to drain and remains in the bucket thus affecting the next measurement, and (4) residual water that remains in the bucket when rainfall ceases and then evaporates.
The debris filter 108 can reside within the interior volume of the collection cone 102 and secure to the interior walls of the collection cone 102 by fitting into and/or resting on a ledge or shelf 118 formed into the interior of the collection cone 102. More specifically, the lower filter section 110 can have a width or diameter that is designed to couple with the ledge 118, and thus rest upon that ledge 118, preventing the debris filter 108 from resting or settling any lower within the collection cone 102 or within the lower interior volume 116 of the collection cone 102. In alternative embodiments, there may be no shelf 118 formed into the interior of the collection cone 102, and the debris filter 108 may simply rest where the diameter of the open area within the collection cone 102 fits and couples with the diameter of the lower filter section 110. The protrusion 114 provides a gripping point that allows an operator to remove, replace, clean, and/or otherwise manipulate the debris filter 108 without adversely affecting the upper filter section 112 or lower filter section 110. Material collected and blocked by the debris filter 108 should be cleaned out and emptied on a regular basis, for proper operation of the gauge.
In alternative embodiments, the debris filter 108 may include engaging members which are configured to couple with and secure to an engagement anchor mounted in the interior of the collection cone 102. In some embodiments, the engagement anchor can be a bar inserted into and extending across the diameter of the collection cone interior. In other embodiments, the engagement anchor can be a groove in the wall of the collection cone 102.
In operation, rainfall or other precipitation that enters the collection cone 102 and the upper interior volume 106 through the precipitation opening 104 is funneled to and passes through the debris filter 108 into the lower interior volume 116. The precipitation fluid is then directed by the walls of the lower interior volume 116 of the collection cone 102 to a delivery port 120, which is an opening at the base of the collection cone 102. Accordingly, the size of pores, holes, or slits of the grate of the debris filter 108 should be smaller than the size of the delivery port 120 opening or orifice. Fluid falls from the delivery port 120 out of the collection cone 102 volume and into the internal space or volume 122 of the collection station 100. The size of the delivery port 120 may be limited in area to regulate and limit the rate of fluid flowing through the opening from the collection cone 102.
Referring to
In embodiments, wires (not shown) can connect a sensor to a microprocessor or other controller unit located within the collector. In some embodiments, the connection between the sensor and controller unit can be wireless. The controller unit can be configured to send out a pulse for each positive increment of water, so that to any connected device or observing user the signal received is the same as from a conventional tipping-bucket or similar collector. The controller unit can also send additional data, such as the rate of collection, the absolute weight of water held, the identity of the collector, and other relevant metrics or identification data. The controller can send some of the information, such as precipitation rate or intensity of precipitation, in the form of an analog voltage or current.
The collection vessel 103 is shown to have a collection arm 128 (alternatively referred to as a bucket, spoon, or cup), rotation tabs 130 constituting the center of rotation in the central portion of the collection vessel 103, a pivot shaft 132, and a resistance arm 134. In some aspects, the resistance arm 134 can have, in a position distal from the rotation tabs 130, an “armature counterweight” 136 which is designed to magnetically couple with a magnet 138 (the armature counterweight in this context referring to the single structure that can function as both an armature and a counterweight). In other aspects, the resistance arm 134 may be a solid piece of material, may be a partially hollow framework, or may have more than one arm, depending on the desired weight for the resistance arm 134. The collection vessel 103 has its pivot shaft 132 coupled to, or extending through a hole in, the rotation tabs 130. There can be two rotation tabs 130 along the width of the collection vessel 103, which allows for the pivot shaft 132 to evenly support the collection vessel. The pivot shaft 132 rests within holes or receiving cavities within the pivot mount 124 on either side of the pivot shaft 132. Thus, the collection vessel 103 is mounted on the pivot mount 124 via the pivot shaft 132 and can rotate (i.e. pivot or tip) around the axis defined by the length of the pivot shaft 132, or in other words, around the center of rotation. As shown in
The collection arm 128 can be shaped and/or tapered to have a pour lip 148 toward the end of the collection arm 128 distal from the pivot shaft 132, such that fluid held in the collection arm 128 is directed to flow out of the collection arm 128 via the pour lip 148, when the collection vessel 103 is in a position to discharge fluid held within the collection arm 128. In embodiments, when fluid is collected in the collection arm 128 and/or when fluid is discharged by the collection vessel 103, a splash shield 126 is positioned to partially surround the collection arm 128 such that fluids entering or exiting the collection arm 128 do not cause any fluid that may splash to fall into or onto other elements of the measurement assembly 101 or collection station 100. In particular, the splash shield 126 may have a ridge that is level with an upper rim of the collection arm 128 when the collection vessel 103 is in a fluid collection and measurement position. In some embodiments, the splash shield 126 ridge can be higher than the upper rim of the collection arm 128, and in other embodiments the splash shield 126 ridge can be lower than the upper rim of the collection arm 128. In such embodiments, the splash shield 126 defines an area or volume where the collection arm 128 will tilt or descend into when the collection vessel 103 is in a discharge position. Fluid that is discharged from the collection arm 128 may pass out of the collection station 100 through a drain 146 in the base of the collection station 100. The drain 146 is configured to be the bottom surface below the collection arm 128 surrounded by the splash shield 126.
The resistance arm 134 of the collection vessel 103 can be configured to hold an armature counterweight 136 on the end of the resistance arm 134 distal from the pivot shaft 132. In embodiments, the end of the resistance arm 134 distal from the rotation tabs 130 can be molded to securely hold the armature counterweight 136. The armature counterweight 136 can magnetically couple with a magnet 138, which in turn is in physical contact with a force gauge 140. In some embodiments, the armature counterweight 136 and magnet 138 may be held in close proximity to each other, but not necessarily in direct contact, in order to control and regulate the attractive force of the magnetic coupling between the two components. The armature counterweight 136 may be a steel element, or other ferrous component, such that the magnet 138 is magnetically coupled with the armature counterweight 136, and provides resistance to any mechanical force (i.e. torque generated by the weight of the collection arm 128 and any fluid therein) acting on the armature counterweight 136 pulling the armature counterweight 136 in a direction away from the magnet 138. When the armature counterweight 136 and magnet 138 are in physical contact with each other (i.e. when the collection vessel 103 is in a collection and measurement position), the armature counterweight 136 and magnet 138 are shaped to be flush against each other as the magnetic attraction holds the armature counterweight 136 and magnet 138 together. As shown in
In one exemplary embodiment, the collection arm 128 can hold an amount of liquid roughly equivalent to about 0.15″ or 4 mm of rainfall or other precipitation. The collection arm 128 can hold a volume of rainfall or other precipitation of about sixty-five to ninety milliliters (65 mL-90 mL). In some embodiments, the collection arm 128 can hold a volume of rainfall or other precipitation of about one hundred eighty milliliters (180 mL). In some embodiments, the collection arm 128 may hold a volume of up to about two hundred milliliters (200 mL). In particular embodiments, the collection arm 128 may hold a volume of up to about two hundred twenty milliliters (220 mL) while being configured to tip once the volume in the collection arm 128 reaches about one hundred eighty milliliters (180 mL). In various embodiments, the collection arm 128 can hold a volume of fluid greater than or less than the volume and ranges considered above. In many embodiments, the collection arm 128 has a symmetrical shape that can be spoon-like, U-shaped, or V-shaped, such that as fluid fills the collection arm, the center of gravity moves along a vertical direction but not to either side of the line of symmetry of the collection arm 128. Accordingly, the length of the lever arm (or “moment”) of collection fluid does not change. The collection arm 128 and/or pour lip 148 may be further shaped to facilitate a rapid discharge of fluid when the collection vessel 103 is in a fluid discharge position.
During operation, the principal forces acting on the collection vessel 103 as it fills with fluid are the torque (alternatively referred to as leverage) generated by the collected fluid and the force of magnetic attraction between the magnet 138 and armature counterweight 136. The torque that acts on the collection vessel 103 is generated by the weight of the fluid collected in the collection arm 128, where the magnitude of the torque is equal to the weight of the fluid multiplied by the distance (i.e. moment arm) from the center of gravity of the fluid to the center of rotation of the collection vessel 103; as used herein, this is referred to as the “collection arm torque”. The weight of the collection arm 128 can also contribute to the collection arm torque. In many embodiments of the measurement assembly, the center of rotation of the collection vessel 103 is along the axis of the pivot shaft 132. The magnetic attraction between the magnet 138 and armature counterweight 136 acts as a holding force in a direction opposite to the amplitude of the torque around the center of rotation; as used herein, this is referred to as the “resistance arm torque”. The weight of the armature counterweight 136 can also significantly contribute to the resistance arm torque.
As shown in
As vibrations from the collection vessel 103 transmit and exert force on the force gauge 140, or as the collection vessel 103 returns to a measurement and collection position as described below, the force gauge 140 itself may experience damage and/or trauma from the shock of the forces and related movement of the resistance arm 134 and/or armature counterweight 163. Accordingly, in some embodiments, a first cushion 142 may be located below the force gauge 140 to prevent the force gauge 140 from moving too far, or over-travelling, in a direction away from the resistance arm 134 and toward the force gauge support mount 144. In such embodiments, the first cushion 142 may be adjustable in relation to its distance from the force gauge 140. Further, in some embodiments, a second cushion 158 may be located between the force gauge 140 and the magnet 138 to prevent trauma or damage to the force gauge 140 as the resistance arm 134 vibrates or exerts a shock or compressive force onto the force gauge 140. The first cushion 142 can have an area that is less than, equal to, or greater than the surface area of the force gauge support mount 144 on which the first cushion 142 rests. The force gauge support mount 144 further provides a stable reference body for the measurement of force.
Once the torque of the fluid F and collection arm 128 sufficiently exceeds the torque of the attractive magnetic force between the armature counterweight 136 and the magnet 138, the negative force (i.e. tension) on the resistance arm 134 and armature counterweight 136 will overcome the strength of the magnetic field coupling the armature counterweight 136 and the magnet 138. Accordingly, the armature counterweight 138 will break free from its physical connection to and/or close proximity with the magnet 138, and the collection vessel 103 will pivot, along the center of rotation defined by the pivot shaft 132 resting on the pivot mount 124, toward the side of the collection arm 128. In an aspect, the amount of fluid F and corresponding weight of the fluid F necessary to generate a collection arm torque sufficient to overcome the resistance arm torque generated by the magnetic attraction between the armature counterweight 136 and the magnet 138 can be an amount of fluid F that completely fills the collection arm 128 volume. In other aspects, the collection arm torque necessary to overcome the resistance arm torque can be generated by an amount of fluid F that only partially fills the collection arm 128 volume. The magnet and armature are configured to separate and allow the collection vessel 103 to pivot and tip before the collection arm 128 fills to the point of fluid F overflowing out of the collection arm 128. In various embodiments, the collection arm 128 can hold a volume of about two hundred milliliters (200 mL) or more. In particular embodiments, the collection arm 128 may hold a volume of up to about two hundred twenty milliliters (220 mL) while being configured to tip once the volume in the collection arm reaches about one hundred eighty milliliters (180 mL). In various embodiments, the collection arm 128 can hold a volume of fluid greater than or less than the volume and ranges considered above. In other words, due to the collection of fluid, the collection arm torque can overcome a threshold force, exceeding the resistance arm torque, at which point the collection vessel 103 can rotate around the axis of rotation defined by the pivot mount 124.
In many embodiments, the collection vessel 103 tips once the weight of the collected fluid F increases collection arm torque sufficiently such that the negative force (tension) on the resistance arm 134 overcomes the resistance arm torque. The weight of the armature counterweight 136 continues to provide a resistance arm torque such that once fluid F is discharged from the collection arm 128, the collection vessel 103 rotates back into a measurement and collection position. In some aspects, the magnetic attraction between the armature counterweight 136 and magnet 138 also contributes to the rotation of collection vessel 103 back into a measurement and collection position. A stream of fluid falling from the delivery port 120 and striking the collection arm 128 exerts a force which resists the return of the collection arm 128 to a collection and measurement position. To limit this force, the diameter of the delivery port 120 can be configured to be made small enough to limit the amplitude of the fluid stream, and the collection arm 128 is positioned such that the delivery port 120 orifice is close to the pivot point of the rotation tabs 130, thus reducing the length of the moment arm of the force. Thus, the collection vessel 103 goes through a periodic cycle of collection and measurement and then discharge. The collection vessel 103 can be designed to pivot and tip, thereby discharging the fluid, before the collection arm 128 overflows. Unlike “tipping bucket’ rainfall gauges known in the art, because the collected fluid F has been measured during its accumulation, the volume at the time of tipping is not significant to record or to base a calculation on for calculating or otherwise determining rainfall or precipitation. Accordingly, any error associated with variation in the volume of fluid F at the tipping point of the bucket, as seen in rain gauges known in the art, does not occur.
In embodiments, the presence of the fluid F collected in the collection vessel 103 is continuously measured and recorded as it is received from the delivery port 120 in the collection arm 128. In such embodiments, measurements are recorded for positive increments of collected fluid weight. Accordingly, when fluid is discharged from the collection vessel 103, as described below, any fluid that fails to drain from the collection arm 128 does not adversely affect or create error in the subsequent collection and measurement of rainfall or precipitation. Rather, the measurement of rainfall or other precipitation is simply based on the sum of the positive increments of fluid F collected between the return of the collection vessel 103 to its collection and measurement position and the next discharge of fluid. In other words, the measurement and recording of weight is zeroed (or re-zeroed) to a new baseline. Thus, error due to remnant or residual fluid, as seen in rain gauges known in the art, is eliminated. Similarly, any remnant or residual fluid in a collection vessel 103 that evaporates after precipitation ceases does not create any error in measurement, because negative incremental changes in weight are ignored and only positive increments of collected fluid weight are the basis for sensing and calculations, thus the microprocessor connected to the force gauge 140 can be configured to not record the decline in weight. Such measurements, configuration, and data processing can be applied with all embodiments of precipitation weight gauge assemblies as disclosed herein.
As considered in the present disclosure, in further contrast with rain tipping gauges known in the art, the volume of fluid that can be held by embodiments of the collection vessel as disclosed herein are greater than the volumes that trigger recording events in known tipping bucket rain gauges. Thus, a collection vessel of the presently-disclosed device may tip to a fluid discharge position less frequently, which depending on the volume of the collection arm, may be five times (5×), fifteen times (15×), thirty times (30×), forty times (40×), or even up to two hundred times (200×) less frequently than tipping bucket rain gauges known in the art. Embodiments of the measurement assembly may collect from about 0.01″ to about 2″ of rainfall or precipitation before discharging the collected fluid. The decreased frequency of fluid discharge thereby reduces the opportunity for errors stemming from missing the measurement of incoming precipitation while the collection vessel is tipping or in the fluid discharge position. Further, any error that does result from rainfall or other precipitation that is missed or not measured during the period the collection vessel is in a fluid discharge position can be corrected for by calculating the precipitation loss based on the measured rate of precipitation and tip duration.
In further embodiments, the resistance arm 134 may be connected to the force gauge 140, or other anchoring point, by a mechanical latch (not shown) in lieu of or in addition to a magnet 138. In such embodiments, the latch may transmit changes in weight to the force gauge 140, and may hold the collection vessel 103 in a measurement and collection position up until the point that the weight of fluid held by the collection arm 128 overcomes the strength of the latch between the resistance arm and the force gauge 140, or between the latch and another anchoring point.
In some embodiments, the weight gauge frame 216 includes a portion referred to as the magnet frame 226, which can project in a direction downward from the plane in which the weight gauge frame 216 is oriented. The magnet frame 226 can further be configured to carry and support a magnet 222. The armature counterweight 212 mounted at the end of the resistance arm 210 distal from the rotation tabs 220 can be a steel element, or any other ferrous component, and can magnetically couple with the magnet 222. The attractive magnetic force between the armature counterweight 212 and the magnet 222 generates a resistance arm torque that provides resistance to any mechanical force (i.e. collection arm torque generated by the weight of the collection arm 208 and any fluid therein) acting on the armature counterweight 212 pulling the armature counterweight 212 in a direction away from the magnet 222. The resistance arm torque thus operates to hold the collection vessel 203 in a position where the collection arm 208 collects and holds any fluid that drops into the collection arm 208. As the collection arm 208 collects fluid, the compressive force resulting from the increased weight is transmitted through the collection vessel 203 and weight gauge frame 216 to the one or more load cells 206 which then emits a signal that can be measured and used to calculate the increase of fluid. As more fluid is collected, the weight of the fluid increases the collection arm torque acting on the collection vessel 203, pushing the collection arm 208 portion downward into the interior volume 201 of the splash enclosure 204. When the collection arm torque is sufficient to overcome the resistance arm torque, the collection vessel 203 will rotate around the pivot shaft 214 to a fluid discharge position. In other words, due to the collection of fluid, the collection arm torque can overcome a threshold force, exceeding the resistance arm torque, at which point the collection vessel 203 can rotate around the axis of rotation defined by the pivot shaft 214.
The collection arm 208 can, in some aspects, hold an amount of rainfall or other precipitation of about 0.15″ or 4 mm in depth. In terms of volume, the collection arm 208 can hold a volume of rainfall or other precipitation of about sixty-five to ninety milliliters (65 mL-90 mL). In some embodiments, the collection arm 208 can hold a volume of rainfall or other precipitation of about one hundred eighty (180 mL). In alternative embodiments, the collection arm 208 can hold a volume of up to about two hundred milliliters (200 mL) or more. In particular embodiments, the collection arm 128 may hold a volume of up to about two hundred twenty milliliters (220 mL) while being configured to tip once the volume in the collection arm 208 reaches about one hundred eighty milliliters (180 mL). In various embodiments, the collection arm 208 can hold a volume of fluid greater than or less than the volume and ranges considered above. The collection arm 208 may be further shaped to facilitate a rapid discharge of fluid when the collection vessel 203 is in a fluid discharge position. Fluid can pass out of the apparatus through a drain positioned along the bottom surface surrounded by the splash enclosure 204.
In such embodiments, the collection vessel 303 is designed to have a collection arm 308, a resistance arm 310, an armature counterweight 312, and rotation tabs 320. In such embodiments of the precipitation gauge measurement assembly 300, the collection vessel 303 is not coupled to a support shaft or pivot mount directly connected to the base of the overall station. Rather, the collection vessel 303 is suspended by a pivot shaft 314 which extends through holes in the rotation tabs 320, and which further extends through holes, or into a cavity, of mounting tabs 328 which are part of the weight gauge frame 316. The mounting tabs 328 can extend from an upper surface of the weight gauge frame 316 and can be configured to align with the holes of the rotation tabs 320. Thus, the collection vessel 303 is suspended on the pivot shaft 314 such that the collection vessel 303 can rotate (i.e. pivot or tip) around the axis defined by the length of the pivot shaft 314. Further, the weight gauge frame 316 is suspended over the splash enclosure 304 by the load cell 306 and the weighing support rod 334, such that the weight gauge frame 316 can rotate around the axis of the weighing support rod 334. In embodiments, the collection arm 308 is positioned on one side of the rotation tabs 320 and pivot shaft 314 while the resistance arm 310 is positioned on the opposing side of the rotation tabs 320 and pivot shaft 314. The pivot shaft 314 can be generally cylindrical, such that it can freely rotate within receiving cavities or holes within the rotation tabs 320 and mounting tabs 328. Fluid that falls from a delivery port above the precipitation gauge measurement assembly 300 is collected in the collection arm 308.
In this embodiment, the weight gauge frame 316 includes a portion referred to as the magnet frame 326, which can project in a direction downward from the horizontal plane in which the weight gauge frame 316 is oriented. The magnet frame 326 can further be configured to carry and support a magnet 322. The armature counterweight 312 mounted at the end of the resistance arm 310 distal from the rotation tabs 320 can be made of steel, ferrous, or any other magnetically permeable material, and can magnetically couple with the magnet 322. The attractive magnetic force between the armature counterweight 312 and the magnet 322 and weight of the armature counterweight 312 generates a resistance arm torque that operates to hold the collection vessel 303 in a position where the collection arm 308 collects and holds any fluid that drops into the collection arm 308. As the collection arm 308 collects fluid, the compressive and/or tensile force resulting from the increased weight is transmitted through the collection vessel 303 and weight gauge frame 316 to the load cell 306 which then emits a signal that can be measured and used to calculate the increase of fluid. Further, as fluid is collected, the weight of the fluid acts on the collection vessel 303 increases the collection arm torque, pushing the collection arm 308 portion downward into the interior volume 301 of the splash enclosure 304. When the collection arm torque is sufficient to overcome the resistance arm torque, the collection vessel 303 will rotate around the pivot shaft 314 to a fluid discharge position. In other words, due to the collection of fluid, the collection arm torque can overcome a threshold force, exceeding the resistance arm torque, at which point the collection vessel 303 can rotate around the axis of rotation defined by the pivot shaft 314. In some aspects, the armature counterweight 312 can be separate elements, an armature and a counterweight, where the armature is magnetically permeable.
In embodiments, the collection arm 308 can hold an amount of rainfall or other precipitation of about 0.15″ or 4 mm in depth. In terms of volume, the collection arm 308 can hold a volume of rainfall or other precipitation of about sixty-five to ninety milliliters (65 mL-90 mL). In some embodiments, the collection arm 508 can hold a volume of rainfall or other precipitation of about one hundred eighty (180 mL). In alternative embodiments, the collection arm 308 may hold a volume of up to about two hundred milliliters (200 mL) or more. In many embodiments, the collection arm 308 has a symmetrical shape that can be spoon-like, U-shaped, or V-shaped, such that as fluid fills the collection arm, the center of gravity moves along a vertical direction but not to either side of the line of symmetry of the collection arm 308. Accordingly, the length of the lever arm of the collection fluid does not change, and length measurements are linear with the volume of collected precipitation. The collection arm 308 may be further shaped to facilitate a rapid discharge of fluid when the collection vessel 303 is in a fluid discharge position. Fluid can pass out of the apparatus through a drain positioned along the bottom surface surrounded by the splash enclosure 304.
In such embodiments, the collection arm 402 is positioned to collect fluid from above the measurement assembly. The collection vessel is held in a collection and measurement position by the weight of the counterweight 408 and attractive magnetic force between the magnet 412 and armature 416. In embodiments, the armature 416 and magnet 412 can be in physical contact with each other when the collection vessel 400 is in a collection and measurement position, and are shaped to be flush against each other as the magnetic attraction holds the armature 416 and magnet 412 together. In other embodiments, the armature 416 and magnet 412 can simply be in close proximity to each other when the collection vessel 400 is in a collection and measurement position. The force gauge 420 is connected to a microprocessor (not shown) which records signals from the force gauge 420. The magnet 412 on the distal end of the collection arm 402 can be in physical contact and/or close proximity with the armature 416 such that any vibration, tension, compression, or other change in force resulting from the addition of fluid to the collection arm 402 is transmitted through the magnet 412 and armature 416, and is sensed by the force gauge 420. The force gauge 420 accordingly detects the tension and/or compression caused by the weight of the water in the collection arm. Thus, the force gauge 420 detects increases in the weight of the fluid held in the collection arm 402 as the fluid is collected. Accordingly, in some embodiments, a cushion 418 may be located below the force gauge 420 between the armature 416 and the force gauge 420 to prevent and shock or trauma on the force gauge 420 resulting from the collection arm 402 and coupled magnet 412 moving too far, or over-travelling, in a direction toward the force gauge 420.
Further, as fluid accumulates in the collection arm 402, the weight of the fluid adds to the collection arm torque pushing the collection arm 402 downward around the center of rotation defined by the pivot shaft 410. The weight of the counterweight 408 and the magnetic attraction between the magnet 412 and the armature 416 generate a resistance arm torque in the direction opposite to the collection arm torque. As in other embodiments, the resistance arm torque operates to hold the collection vessel in a collection and measurement position, while the collection arm torque operates to move the collection vessel to a fluid discharge position.
In embodiments as illustrated, the weight gauge frame 516 is suspended by a support shaft 511 which extends through holes in weighing rotation tabs 513 and weighing rotation mounts 515. The weight gauge frame 516 can include magnet frame 526, which can project in a direction downward from the plane in which the weight gauge frame 516 is oriented. The magnet frame 526 can further be configured to carry and support a magnet 522. The armature counterweight 512 mounted at the end of the resistance arm 510 distal from the tipping rotation tabs 520 can be a steel element, or any other ferrous component, and can magnetically couple with the magnet 522. The attractive magnetic force between the armature counterweight 512 and the magnet 522 generates a resistance arm torque that provides resistance to any mechanical force acting on the armature counterweight 512 pulling the armature counterweight 512 in a direction away from the magnet 522. The resistance arm torque thus operates to hold the collection vessel 502 in a position where the collection arm 508 collects and holds any fluid that drops into the collection arm 508. Fluid that drops into the collection arm 508 causes the weight gauge frame 516 to rotate around the axis of the weighing support shaft 511, which can cause a projection tip 523 to apply increased force upward, toward a force sensor 519. As more fluid is collected, the weight of the fluid increases the collection arm torque acting on the collection vessel 502, pushing the collection arm 508 portion downward into the interior volume of the splash enclosure 504. When the collection arm torque is sufficient to overcome the resistance arm torque, the collection vessel 502 will rotate around the pivot shaft 514 to a fluid discharge position, as shown in
The weight gauge frame 516 can further include the forward cover 517 that extends over and covers at least a portion of the collection arm 508 and provides rigidity to the weight gauge frame 516. In some aspects, the forward cover can prevent loss of fluid held in the collection arm due to splashing or other mechanical agitation of the collection vessel 502. In some aspects, the forward cover 517 can be shaped to have a flat or converging front end which can be configured to come into contact with the force sensor 519. In other aspects, the forward cover 517 can include the projection tip 523 which can directly contact and transmit force to the force sensor 519. The force sensor 519 can be supported on a mounting structure 521 extending from the splash enclosure 504. In particular, the force sensor 519 can detect increments of weight increase as the collection arm 508 collects fluid. When the collection vessel 502 tips and empties fluid held by the collection arm 508, the weight gauge frame 516 can return to a balanced position about the axis of the weighing support rod 511, exerting an amount of force through the projection tip 523 onto the force sensor 519 indicative of an empty collection arm 508, thereby allowing the force sensor 519 to reset and assume a zero value in order to again begin measuring increments of weight. In aspects, the force sensor 519 can also measure the force generated by the armature counterweight 512 contacting the magnet 522 when the collection vessel 502 rotates back to the collection position.
Further illustrated in
The collection arm 606, resistance arm 618, and armature counterweight 614 collectively hang from the support frame 604, attached at two pivot points by the pivot mount 616. As noted in other embodiments, when the collection arm 608 is empty, the collection arm 608 is held in a substantially horizontal position by two forces, the weight of the armature counterweight 614 and the attractive magnetic force between the armature counterweight 614 and the magnet supported by the support frame 604. The collective weight of the collection arm 606, resistance arm 618, and armature counterweight 614, as well as the weight of the support frame 604 itself, cause a rotational force on the support frame 604 about the weighing pivots 652. In aspects, the weighing pivots 652 can have an edge (optionally referred to as “knife-edged”) so as to provide for a minimum-friction, minimum-stiction bearing for transfer of weight to the load cell 610. The weight of the support frame 604 and rotation is counteracted by the force exerted by the load cell 610 on the support frame 604 via the load pad 656. The load cell force 610 causes generation of an electrical signal by the load cell 610, the amplitude of that signal providing for a measure of the weight of the support frame 604, collection arm 606, resistance arm 618, and armature counterweight 614.
As liquid is collected in the collection arm 606, the increases of weight cause increases the amplitude of the load cell 610 output signal. These incremental increases are a measure of the liquid collecting in the collection arm 606. During a given collection period, the signal increments are monitored by a microcomputer in the control circuitry and reported as output signals indicating increments of rainfall. Increments of precipitation that can be detected and measured can be about 0.01″ of rainfall, 0.1 mm of rainfall, or both. Other data, such as rate of rainfall, can also be detected and reported.
As in other embodiments, as the weight of collected liquid increases, the rotational force about the tipping pivot (i.e. pivot mount 616) increases the force tending to pull an armature counterweight 614 away from a magnet. When the force of the weight exceeds the retention force of the magnetic field, the collection arm 606 and resistance arm 618 assembly will be released to rotate about the tipping pivot axis, and dump the collected liquid. In some aspects, the weight exceeding the retention force can be about 180 grams of collected precipitation, which is approximately equivalent to about one-third (⅓″) of an inch of rainfall. Similarly, when the collection arm 606 has emptied, the weight of the armature counterweight 614 causes rotation of the collection arm 606 and resistance arm 618 back to a horizontal collection position, and the detecting of incremental weight increases is resumed. In aspects, a microprocessor or computer can perform an auto-zeroing or re-zeroing after each dump of fluid, such that only positive increments of weight are recorded. Accordingly, no errors result from water remaining in the collection 606 arm after a dump of liquid, or from evaporation between rainfall events.
The base adaptor can further include a module 705 that can house a circuit board containing a microprocessor and other interface electronics for communicating with non-transitory computer-readable mediums coupled to the precipitation gauge measurement assembly 700. In some aspects, the securing points can be threaded apertures for screws to secure the base adaptor 704 to the base assembly 702. The base adaptor can further include an adaptor roof 708 constructed to span the width of the base adaptor 704 and, in some aspects, provide structural strength and rigidity to the base adaptor 704. The adaptor roof 708 can further include a passage 712 through which precipitation can pass through, so as to fall into the collection vessel 703. In further aspects, the adaptor roof 708 can in part prevent fluid that falls into the collection arm 714 from splashing or scattering outside of the space defined between the collection arm 714 and the adaptor roof 708.
The collection vessel 703 can include a collection arm 714 and a counterweight arm 706, where the counterweight arm 706 is configured to hold a counterweight 716. In some aspects, the counterweight arm 706 can be molded to have an articulated beam extending across the width of the collection vessel 703 and connecting two extensions forming part of the counterweight arm 706. The articulated beam of the counterweight arm 706 can provide for structural strength and rigidity to the counterweight arm 706, and can further be molded to have spaces or openings so as to have the counterweight arm 706 meet a target weight. The collection vessel 703 is mounted to the base adaptor 704 via a pivot rod 722, where the collection vessel 703 can rotate around the axis defined by the pivot rod 722. The pivot rod 722 can be supported by rotation tabs that are part of the structure of the base adaptor 704, where the collection vessel 703 is suspended on the pivot rod 722 such that the collection vessel 703 can rotate around the axis defined by the length of the pivot rod 722. The collection arm 714 and counterweight arm 706 of the collection vessel 703 hang from the base adaptor 704, attached at two pivot points via the pivot rod 722. The pivot rod 722 can be generally cylindrical, such that it can freely rotate within receiving cavities or holes within the rotation tabs of the base adaptor 704.
Similar to other embodiments herein, when the collection arm 714 is empty, the collection vessel 703 is held in a substantially horizontal position by two forces, the weight of the counterweight 716 and the attractive magnetic force between the magnet 718 and the armature unit 724, which is attached to a load cell 710 such that force exerted upon the armature unit 724 is sensed by the load cell 710. The counterweight 716 applies a force that urges the collection vessel 703 toward the collection and measurement position where the counterweight arm 706 is urged downward at least in part by the weight of the counterweight such that the collection arm 714 of the collection vessel is urged upward toward the plane of the base adaptor. In some aspects, the base assembly 702 can have a curved ramp positioned along the rotation path of the collection arm 714. The curved ramp can be cylindrical in shape and can function to retain water in the collection arm 714 until the collection arm moves past a base point of the curved ramp and the collection vessel 703 is in the fluid discharge position. The structure of the curved ramp in combination with the rotation path of the collection arm 714 provides for a steep tip angle, such that when the weight of the water carries the tip of the collection arm 714 past the base point of the curved ramp, the steep tip angle ensures that the discharge of fluid from the collection arm 714 is complete, discharging all, or almost all, fluid held in the collection arm 714.
The base adaptor 704 is further configured to support the load cell 710 located proximate to the tip of the collection arm 714, when the collection vessel 703 is in a collection and measurement position. The load cell 710 can be further supported on a support plate 720, where either or both of the load call 710 and the support plate 720 can be constructed of a metal such as aluminum. The load cell 710 and support plate 720 can be machined to mechanically couple with each other, such that the load cell 710 has an area within or equal to the perimeter of the support plate 720. In some aspects, the support plate 720 prevents the load cell 710 from over-extending or over-stressing in a downward direction due to the strain from the weight of the collection vessel 703 and fluid held within the collection arm 714, applying force on the load cell 710 through the magnet 718 and armature unit 724 or any other external force. In further aspects, the load cell 710 can rest on top of and be coupled to the support plate 720. In other aspects, the load cell 710 can fit into and mechanically couple with a recess of the support plate 720.
As seen in
As liquid is collected in the collection arm 703, the increases in weight cause increases in the amplitude of the load cell 710 output signal. These incremental increases are a measure of the liquid collecting in the collection arm 703. During a given collection period, the signal increments are monitored by a microcomputer in the control circuitry and reported as output signals indicating increments of rainfall. Increments of precipitation that can be detected and measured can be about 0.01″ of rainfall, 0.1 mm of rainfall, or less. Other data, such as rate of rainfall, can also be detected and reported.
Optionally, as shown in
As in other embodiments, the magnet on the a collection arm lip is held to the armature fixture 810 as the collection arm collects water. The collection arm is released when the weight of the water overcomes the magnet field's retentive force; the collection arm then tips. When the collection arm returns to the collection position, either or both of the first cushioning pad 808 and the second cushioning pad 814 acts as a cushion to absorb a portion of the shock and vibration caused by the impact of the collection arm magnet on the armature fixture 810. Moreover, the ceiling of the channel in the support plate 802 prevents excessive upward movement of the load cell 804 past horizontal.
In many aspects, the data measured by load cells in embodiments of the present disclosure can be representative of the weight of fluid in a collection vessel, a precipitation rate, a precipitation intensity, electrical signals analogous to clicks of a tipping bucket as the collection vessel collects fluid, and variations and combinations thereof. In other aspects, load cells as disclosed herein can be machined metal components, cut to allow for flexibility in the metal structure, and coupled with one or more wires to a differential amplifier, further connected to a non-transitory computer readable medium that is local to the rain gauge and/or remote from the rain gauge. In further aspects, data from a load cell can be continuously transmitted to a non-transitory computer readable medium through wired or wireless communication elements. In yet further aspects, data from a load cell can be transmitted or read in increments or batches to a non-transitory computer readable medium.
Further alternative embodiments of the precipitation weight gauge measurement assemblies discussed above can be configured to transpose the positions of the magnet and armature and/or armature counterweight. In other words, in embodiments of the measurement assemblies, each paired magnet and armature can be swapped in terms of how and where the magnet and armature are mechanically coupled to the structure of the measurement assembly.
As provided herein, the force gauge and/or load cells which sense compressive and/or tensile forces are electronically coupled with non-transitory computer readable mediums, such as microprocessors or processors connected for transmission to the Internet. A force gauge and/or load cell can be electrically coupled to a microprocessor (or equivalent) by wires or by wireless means and thereby send sensory signals to the microprocessor. The coupled microprocessor which collects the sensory data from the force gauge and/or load cell can further relay sensed information to other non-transitory computer readable mediums, and/or run calculations on collected data and relay the calculated result to a user-operable and/or user-readable display. The signals detected by the force gauge and/or load cells can be filtered by the microprocessor (either through hardware or software) to base calculations only on signals that indicate positive increment of weight or force.
As provided herein, the collection vessel can be considered a lever, where the fulcrum of the lever is positioned at the rotation section and pivot mount (i.e. at the middle of the lever), between the collection arm and the resistance arm; thus the collection vessel can be considered a Class 1 lever. In such embodiments, the resistance on the lever, the torque that acts on a collection vessel toward a collection and measurement position, is provided by the magnetic coupling of the magnet and the armature and/or armature counterweight and the weight of the counterweight. Conversely, the effort force on the lever, the torque that acts on a collection vessel toward a fluid discharge position, is primarily provided by the weight of the fluid F held in the collection arm. However, in alternative embodiments, the fulcrum of the lever may be positioned at an end of the lever, such that either the effort torque or the resistance torque may be located in the middle of the lever; i.e. as a Class 2 or a Class 3 lever, respectively.
The above description is illustrative and is not restrictive, and as it will become apparent to those skilled in the art upon review of the disclosure, that the present invention may be embodied in other specific forms without departing from the essential characteristics thereof. Further, throughout the foregoing description, for the purposes of explanation, numerous specific details were set forth in order to provide a thorough understanding of the invention. It will be apparent, however, to persons skilled in the art that these embodiments may be practiced without some of these specific details. These other embodiments are intended to be included within the spirit and scope of the present invention. Accordingly, the scope of the invention should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the following and pending claims along with their full scope of legal equivalents.
The present patent application claims the benefit of priority to U.S. Provisional Patent Application No. 61/969,511 filed on Mar. 24, 2014, which is hereby incorporated by reference.
Number | Date | Country | |
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61969511 | Mar 2014 | US |