CA3115927A1

CA3115927A1 - The rgs-200 siphoning rain gauge

Info

Publication number: CA3115927A1
Application number: CA3115927A
Authority: CA
Inventors: Albert Internicola
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-04-19
Filing date: 2021-04-19
Publication date: 2022-10-19

Abstract

The invention relates to the development and replacement of the siphon used in Canadian Patent 2157943 the RGS-100 Siphoning Rain Gauge. Other critical improvements were also implemented. A microprocessor is used to calibrate the unit after every siphoning cycle. The apparatus and method for measuring the rate and total amount of rainfall, without moving parts, having a measuring chamber such that upon the water reaching a predetermined level it is measured. Unlike the previous siphon used in Canadian Patent 2157943 this siphon will always self purge and will be clear of air bubbles or water droplets. The siphoning process is self-commencing and stopping and repeats indefinitely. The water level is measured incrementally, electronically and converted to a signal representative of the amount of liquid in the measuring chamber. Other sensors may be attached to the measuring chamber so that other water parameters can be measured.

Description

DESCRIPTION AND SPECIFICATIONS
THE INVENTION PROVIDES IMPROVEMENT TO THE SELF SIPHONING
RAIN GAUGE CANADIAN PATENT # 02157943 AND THE SELF PRIMING
INVERTED 'X SIPHON
The inventor of the device in this application, Albert Internicola, is also the inventor and owner of the Canadian patent #2157943.
This invention provides an improvement to inverted 'X siphons. A device that allows the self-siphoning of continuous flowing liquids, inputted into a chamber, where it is measured and or analyzed. At a predetermined level, the aforementioned liquid is then siphoned from the chamber to the outside. The invention's major applications are as a solid-state rain gauge and a low-level flow meter as described in Canadian patent # 02157943. Also, this invention provides improvements to Canadian patent #02157943 known as RGS-100, RGS-10OHL and Alluvion-100. Some methodologies to the use of the invention are also described.
Other applications include where there is a need to analyze a flowing liquid without the disruption to its input flow, and the user does not need or cannot use man-made power equipment such as pumps and the like to analyze this liquid.
The following is a partial copy of Canadian Patent # 02157943 under Specifications. It also applies to this application.
"This invention relates to a device and method for determining the rate and total amount of rainfall and is particularly useful for environmental monitoring.

Presently, there are two ways of measuring rain fall: The Type "B" AES
Manual Rain Gauge and the Tipping Bucket Rain Gauge. The Type "B" AES
Manual Rain Gauges is constructed of ABS and consists of a funnel attached to a clear graduated holding chamber. The funnel and chamber are held in a circular shell. Rain is collected by the funnel and directed into the measuring chamber. To read the results, the funnel is pulled up and the water level is read on the graduated cylinder. After taking a reading, the chamber is emptied, and the funnel replaced in the shell. Atmospheric Environment Canada (AES) has many of these units in use across Canada and volunteers phone AES after every rain fall with the results. This is presently the most accurate device available to measure rainfall and its accuracy remains constant at all rates of rain fall. A screen on the funnel prevents dirt from entering the cylinder.
This method cannot be used for remote sensing because of its dependence on human beings. So, placing it in a remote, hard to access area is impractical. It is imperative that a reading be taken immediately after a rainfall so that evaporation and overfilling do not affect the accuracy of the data.
Volunteers often neglect this duty and either lie about the results or enter no data at all. This unit cannot measure the rate of rainfall, only the total amount.
The Tipping Bucket Rain gauge was designed around the time of the Second World War. The purpose of this unit is to monitor rain at a remote area. The tipping bucket is a teeter totter type device pivoted in its center with a magnet attached to it. Each side of the teeter totter has a small container that collects the rain. A reed switch is extended from the stationary pivotal point so when the magnet passes it, the magnetic field causes the switch to close momentarily. The reed switch is interfaced to a recorder. A funnel collects the rain and diverts it to the tipping bucket. Every time the tipping bucket tips, the

- 2 -water it has collected is dumped and the other bucket lines up bellow the funnel. The only advantage to the unit is that it can easily be placed in any remote location.
The disadvantages of the unit are that it can only be calibrated for one rate of rainfall. The further the rate of rainfall is from the calibrated rate, the greater the error. If any dirt or insects' nests get in the pivotal point or the buckets then the unit is uncalibrated. This usually occurs within 2 weeks of it being in the field. Calibration is expensive and time consuming and cannot be properly done in the field. This unit cannot measure the rate of rain accurately because it is accurate at only one rate of rainfall.
The present invention is a device and method for avoiding the aforementioned problems and has been shown to be capable of accurately measuring the rate of rainfall and the total amount of rainfall.
Rather than rely on mechanical means, a method has been devised to measure the rain incrementally which discards the accumulated rain when it reaches a predetermined level without the use of moving parts. More particularly, a siphon has been employed to empty the chamber at the predetermined level and a solid-state level sensor is used to measure the rain incrementally.
In a regular inverted 'U siphon, suction applied to the longer leg causes liquid to move up the shorter leg, over the bend and down the longer side. The hydrostatic force due to gravity is larger on the longer leg, and keeps the water through it, even though it has to move up the shorter leg against the pull of gravity. Once started, the flow will continue until air enters the lower siphon leg and breaks the hydrostatic force. Under normal circumstances, the suction to begin the process could be provided by a pump but in remote areas this is not possible as power must be conserved. Therefore, the siphoning must be

- 3 -self-commencing. The inverted "U" siphon is placed in chamber such that the top of the bend is at the height at which we want the water siphoned. As the water level rises in the chamber, it rises in the tube until it rises to the top of the outside of the bend in the tube, whereupon any small rise in the level of the liquid causes water to move down the long side of the siphon, beginning the siphoning process. The rate of flow accelerates with time causing a very quick (approximately I second) emptying of the measuring chamber. When the water level in the chamber reaches the bottom of the short leg, air enters it, causing the siphoning action to stop. This cycle repeats indefinitely, and siphoning occurs at the exact same water level each time."
A better understanding of the invention is best described by referring to the following diagrams:
Figure 1 is a side view and detailed illustration of the inverted 'X siphon, Figure 2 is a detailed cross sectional view the inverted 'X siphon, Figure 3 is the overall depiction of the invention showing a detailed application of and an upgrade to Canadian Patent #2157943, Figure 4 is a detailed illustration showing the level sensor and an upgrade to Canadian Patent # 2157943, Figure 5 is a detailed illustration showing the siphon placed in the level sensor and holder and an upgrade to Canadian Patent #2157943, Figure 6 is a detailed illustration showing a cross sectional view of the invention in an application and an upgrade to Canadian Patent #
2157943, Figure 7 is a detailed diagram showing the debubbling tube and an upgrade to Canadian Patent #2157943,

- 4 -Figure 8 is a diagram showing a basic inverted ',I' siphon theory and some common problems. This diagram is used for ease of explanation and is not part of the application.
A copy of Canadian patent #02157943 and its diagrams as listed on the Canadian Patent database is included and will be referred to in this application. In this description when referring to the diagrams in patent #02157943, it is stated as the actual item number and diagram number as described in the original patent, for example "figure 4, item 3 of patent number 02157943", or figure 4¨ 14 of patent # 02157943 or item 4, of figure 5 of patent number 02157943. When the patent number is not mentioned then the reference is to the diagrams in this application as described above figure 1 to figure 8.
BACKGROUND OF THE INVENTION
Inverted V type siphons, also known as inverted `U' siphons, are mostly used in rain gauges for remote data collection. Their biggest strength is their ability to self-siphon. Common material used to make these siphons copper or other metal and ultra-high molecular plastics. An example of plastics used to create a siphon is in Canadian Patent #2157943, by Albert Internicola.
BASIC PRINCIPLE OF OPERATION
Figure 8 shall be used as an aid to better explain the principle of operation as well as issues that were encountered with the rain gauge built as per Canadian Patent # 2157943. References to diagrams in Canadian Patent #
2157943 will also be used.

- 5 -Rain is collected via the funnel, (figure 8 ¨ 17) and figure 1, item 1 of Canadian patent number 02157943. It is routed via the debubbling tube, (figure 8 ¨ 8) and figure 1, item 3 of Canadian patent number 02157943 to the measuring chamber (figure 8 ¨2) and figure 1, item 4 of Canadian patent number 02157943. As more water is inputted into the measuring chamber its volume increases as does its level. This action is sensed and measured by the Level Sensor item 11, of figure 8 (figure 2, item 5 of patent number 02157943), and send via electrical cable (figure 8 ¨ 14, and figure 2, item 10 of Canadian patent #02157943) to the electronics (figure 8¨ 13) where it could be stored or sent to a user chosen storage device (figure 8 ¨ 15). The water also travels up the Inverted J Siphon (item 1, of figure 8) and Figure 2, item 11 of Canadian patent # 02157943. As more fluid enters the measuring chamber it travels up the siphon, around its bend (figure 8 ¨ 5, and figure 4 -17 of Canadian patent # 02157943). The combination of pressure created by more fluid in the measuring chamber as well as the pull of gravity causes the water to travel further down the siphon until it goes past point 16 of figure 8. At this point self-siphoning commences and empties the measuring chamber in approximately a second. This process repeats indefinitely as long as water enters the measuring chamber. If the rain stops prior to the water level in the Measuring Chamber can commence siphoning it does not matter for this rain has been measured by the Level Sensor. A fuller technical explanation will be given later in this application.
PROBLEMS AND ISSUES WITH CANADIAN PATENT # 02157943.
For an application where the liquid, for example rain, is constantly flowing into a measuring chamber and a parameter needs to be measured, these siphons have one or both of two basic weaknesses. The siphoning time is very slow.

- 6 -This would allow an unacceptable amount of liquid to enter the measuring area during siphoning time. All liquid entering the chamber during siphoning cannot be measured. Therefore, the accuracy of the equipment drops dramatically as the rate of liquid input increases. The other weakness is the inability to predict at what level of liquid the siphoning process commences.
The first time the siphon siphons, the level could be somewhat predicted if the said siphon is made of slippery material such as Teflon, ultra-high molecular weight polyethylene (UHMW), or any other fluoropolymer plastics. These products have a percentage water absorption factor of less than 0.05% and a very low friction coefficient. The unpredictability is high if the siphon (item 1, of figure 8) (item 11, of figure 2 of Canadian Patent 02157943) and the measuring chamber (item 2, of figure 8) (item 4, of figure1 of Canadian Patent 02157943) is made of some metal such as brass, copper, aluminum, or steel.
The natural adhesion of the liquid to the metal, combined with unknown amount of oxidation would contribute highly to this unpredictability.
The most significant area of unpredictability is from bubbles (item 3 and 4, of figure 8) created from the siphoned liquid and air, left behind, at times, in the siphon from the previous siphoning cycle. As the siphoning cycle comes to its end, air is introduced into the flow. The air is introduced from the siphon opening (figure 8 ¨ 6) and holes in the siphon, item 16, figure 4 of Canadian patent # 02157943. The mixture of air and liquid as well as the natural adhesion of the liquid to the inner walls of the siphon creates the said bubbles. Observation has shown that depending on the liquid, these bubbles could occur anytime from every siphoning cycle to every third cycle. The bubbles are large enough to cover the inside diameter of the siphon. Also, they may be deposited anywhere in the length of the siphon but most often in

- 7 -the area where the siphon bends (item 5, of figure 8) (item 17, of figure 4 of Canadian Patent 02157943), and somewhere along the long side of the siphon (figure 8 ¨ 10). As more liquid enters the measuring chamber it also enters the entrance to the siphon (item 6, of figure 8) and (item14, of figure 4, of patent # 02157943) creating a suction / pressure between the said liquid and the bubbles (items 3 and 4 figure 8). As the liquid continues to rise the pressure (item 7, of figure 8) causes the bubble (item 3, figure 8) to be pushed past the knee (item 5 figure 8). Eventually gravity will act on the bubbles such that they commence traveling down the long arm of the siphon (item 10 figure

8). Suction is now created in the area in the siphon (item 7 figure 8) between the bubbles and the liquid. As bubble 4, figure 8 continue traveling down the long arm of the siphon (item 10 figure 8) it will draw bubble 3, figure 8 and the liquid in the measuring chamber (figure 8 ¨2 and figure 1 ¨4 of Canadian Patent # 02157943) up the siphon. If bubble 4, figure 8 goes past the self-siphoning point (figure 8 ¨ 16) siphoning will commence. Siphoning will continue if the suction between the bubble and the liquid is maintained or if the liquid reaches the self-siphoning point (figure 8 ¨ 16). The measuring chamber (figure 8 ¨2, and figure 1 ¨4 of Canadian patent # 02157943) is emptied prior to it being filled. The introduction of more siphoning cycles introduces inaccuracies into the system because rain cannot be measured during siphoning. If the suction between the bubbles and the liquid is disrupted such that the bubbles pop, then, siphoning will stop, causing liquid to flow back into the chamber. This liquid may or may not be measured or give wrong data depending on the type of sensor used. In patent #
02157943 incorrect data would be significant due to the nature of the level sensor (item 5 and 6, in figure 2, of patent # 02157943). The level sensor is designed such that metal pins protrude at different heights (item 5 and 6, in figure 2, of patent # 02157943). As the water rises in the measuring chamber (item 4, figure 1, of patent # 02157943) it reaches the different pins and conductivity occurs between that pin and ground. The electronics connected to the unit translates this conductivity as a measurement of level. If the water returns into the chamber, then that water is measured twice.
The rain is collected by the funnel (item 1 figure 1 of patent # 021517943 and figure 8 - 17), travels down the debubbling tube in patent #021517943 (item3, figure 1 of patent # 021517943), (items 8 and 9 of figure 8) falls into the measuring chamber (item 4, figure 1 of patent #021517943), and (item 2, figure 8) causing large disturbances in the previous collected liquid. This disturbance can introduce air into the siphon and prevent proper siphoning.
Also, these disturbances cause small waves. As the water rises in the measuring chamber, the peaks of these waves will touch the level sensor's pin (item 5 and 6, in figure 2, of patent # 02157943) repeatedly, prior to the true level of the water reaching it. The result being false counts sensed by the electronics.
Other problems with the siphon in patent # 021517943 are the lower bend of the knee (item 15, figure 4 of patent # 02157943). This bend is too sharp.
Due to this, at very low flows, siphoning may not occur. As the water reaches this point, instead of continuing such that the full inner diameter of the siphon is full of water, at times, it just drips or trickles on the inner side of the long side of the siphoning tube (item 11 figure 4 of patent # 02157943). When this happens, siphoning does not occur. Therefore, all future incoming rain cannot be measured.

- 9 -During heavy rainfall, water enters the measuring chamber too fast for the siphon to stop siphoning. This is because air cannot quickly be introduced into holes 16, figure 4 of Canadian Patent # 02157943. The siphon will continue sucking all or some of the new rain from the chamber without it being sensed by the level sensor (figure 8 ¨ 11, and figure 2 ¨5 of Canadian patent #02157943). This increases the rain gauge inaccuracies to an unacceptable level.
The level sensor's pins (items 5 and 6 of figure 2, items 6 and 18 of figure 3, of patent # 021517943) are not insulated. Therefore, at times, after a few siphoning cycles, water does collect on the pins and short with each other. As long as they are electrically shorted, they cannot sense any new rain.
SUMMARY OF THE INVENTION
The invention takes advantage of laws of physics as described by Poiseuille and Bernoulli. An overall description of the invention and an application will be given first. Next, the components that make the invention will be described individually. And then the invention will be presented in detail as related to its components. The aims are to show the invention's uniqueness and how it is an improvement to Canadian patent # 021517943. As mentioned above this inventor is the inventor of Canadian patent # 021517943. Figure 3 shows the overall depiction of the invention. For ease of clarification, the level sensor-siphon holder unit (item 4, figure 3) is shown outside of the measuring chamber (item 3, figure 3). This unit (item 4, figure 3) is inserted into the measuring chamber (item 3, figure 3) such that the '0' ring (item 5, figure 3), and the lip of the level sensor-siphon holder (item 6, figure 3) rests on the base (item 7, figure 3) at the bottom of the measuring chamber. And it is held

- 10 -in place with the plastic nut (item 8, figure 3). The plastic nut screws into the measuring chamber via its threads (item 9, figure 3). The liquid being rainwater in the instrument described in Canadian patent #021517943, is collected by the funnel (item 1, figure 3) and routed via the debubbler tube (Item 2, figure 3) to the sides of the measuring chamber (item 3, of figure 3).
At this point the water spreads across and clings to the sides of the measuring chamber and slides to the bottom. This action removes any bubbles and allows the new collected water to be added to previous collected water without causing disturbances or waves to the said collected water. The level sensor consists of a Teflon tube (item 10, figure 3) with 7 stainless steel pins (item 11, figure 3) set at different heights. The height of the pins corresponds to the level of water in the chamber. Stainless steel is used to prevent oxidation. One of the pins (item 12, figure 3) is ground and runs the full length of the tube (item 10, figure 3). The pins are soldered to individual wires (item 8 figure 6) and are incased in the tube with epoxy resin (item 15 figure 6). As the water rises in the measuring chamber, it shorts out the pin corresponding to that height to the ground pin. The level sensor connects to an electronic circuit (item 13 figure 3) that translates the water shorting the level sensor pins to amount of rainfall. The electronics (item 13 figure3) consists of a microprocessor and associated circuitry. The microprocessor has been programed to sense false readings, compensates for different rate of rain fall, and constantly calibrates the unit. This adds to the accuracy of the invention.
Also, with a few changes to the microprocessor program, this action can also be translated to liquid flow and the unit can be used as a low-level flow meter.
As the water (or liquid) rises, it also goes inside the siphon (item 14, figure 3).
Once the water reaches a preset level above the siphon, it causes the siphon to self-siphon. The liquid then siphons out onto the ground. The level where

-11 -the self-siphoning commences is calibrated by moving the siphon up or down and is accomplished by loosening the compression fitting's nut (item 15 figure 3) and moving the siphon (item 14, figure 3) up or down to the proper level.
Items 16 figure 3 are screens, which allow air into the measuring chamber during siphoning. The unit as shown in figure 3 is placed in an outer shell.
The bottom of the siphon tube (item 17 figure 3) sticks out the bottom of the shell so that the water is siphoned outside of it. Other sensors may be applied with or replace the level sensor to measure other characteristics of the liquid.
These characteristics may be ph, turbidity, salinity, conductivity, oxygen content etc... This could be done while measuring its rate and total amount of flow.
The material to make the siphon as shown in figure 1 and 2 is a plastic that has a percentage water absorption factor of less than 0.05% and a very a low coefficient of friction such as Teflon, ultra-high molecular weight polyethylene (UHMW), or any fluoropolymer resin plastics. It was found that the best product to use is Polytetrafluoroethylene (PTFE) Teflon tubing with an inside diameter of 0.635 centimeters and an outside diameter of 1.0 centimeter. But depending on the type of liquid to be measured any plastics with similar or other diameters as described above will be appropriate. The siphon is molded or bent to create what is shown in figures 1 and 2. Diameter 01 in figure 1 must be larger than diameter 02 in figure 1 by a ratio of greater or equal to 1.15:1. Diameter 03, figure 1 shrinks up to 0.8 of its original diameter 02 (item 11 figure 1). This is critical to the operation of the invention. It will be discussed later. Sector 1 of figure 2 and sector 12 of figure 1 should be as deep as possible without damaging the inner melt of the siphon (item 11 of figure 1 and item 3 of figure 2). This sector ends at an

-12-angle of approximately 90 degrees (section 2 of figure 2). This sector (sector 1 of figure 2 and sector 12 of figure 1) is roughed up as shown in detail 1 in figure 2. The inner melt (item 3, figure 2) is rounded so that it curves proportionally with the outside arc (item 4 of figure 2). Item 5 figure 2 is a hole and has a diameter of 0.994mm to 1.0414mm (diameter 04 figure 1) depending on the type of liquid to be siphoned. This hole commences at the very top and center of the inner top curve (item 6 figure 1) of the siphon. It travels at an angle of 25 to 45 towards the longer leg of the siphon as shown in figure1 angle e6. Diameter 05 of figure 1 (and item 6 of figure 2) has a diameter of 0.994mm to 1.0414mm.
Both the siphon and the level sensor are held in place by the Siphon and Level Sensor Holder (figure 5) and it is made of Ultra High Molecular Weight Polyethylene (UHMW). The Siphon and Level Sensor Holder is also shown in item 6 figure 3, item 13 figure 4, item 10 figure 5 and item 39 figure 6. As mentioned above, the measuring level and siphon holder is then placed in the measuring chamber (item 3 figure 3). The measuring chamber is made of clear PVC. All these plastics (virgin Teflon, PTFE Teflon, UHMW
polyethylene, and the clear PVC) have a very low friction coefficient. This eases the flow of the liquid to be measured in and out of the measuring chamber during operation.
The purpose of the debubbling tube (figure 3 - 2, figure 6¨ 16, and figure 7) is to direct the liquid to be measured from the funnel (figure 3 ¨ 1) to the measuring chamber (figure 3 ¨ 3). Also, the debubbling tube removes all bubbles, and dampens the velocity of the liquid; preventing large disturbances in previous collected liquid in the measuring chamber. Threads at the top of

-13-the debubbling tube (item 1, figure 7) allow it to be screwed into the funnel and hold it in place. The water travels down the center of the tube (item 2, figure 7). Its speed is first dampened upon it reaching the 1200 angle, plus or minus 15 , bend (item 3, figure 7) (item 16, figure 6). The liquid reaches the end of the tube (item 4, figure 7) (item 17, figure 6), hits the sides of the measuring chamber (item 18, figure 6), and spreads out. This action removes all bubbles and dampens the speed of the liquid. The liquid then leaves the debubbling tube via its bottom (item 19, figure 6) (item 5, figure 7). The liquid then travels down the side of the measuring chamber (item 20, figure 6). This action allows the liquid to be added to previous collected liquid without causing ripples or bubbles. It is imperative that the end of the debubbling tube (item 17 and 19 figure 6) is far enough away from the level sensor (item 1 figure 6) as to not create electrical interference on the level sensor pins (items 4, 3 and 30 figure 6). It was found that the best location for the end of the debubbling tube (item 17 and 19 figure 6) is directly over the siphon as shown in figure 6.
The operation of the unit and the self-siphoning process is as follows. The liquid is collected by the funnel (item 1 figure 3) and routed via the debubbler tube (item 2 figure 3) to the inside wall of the measuring chamber (item 3 figure 3, and item 20 figure 6). At this point the bubbles are removed, the

-14-liquid spreads around the inner surface of the measuring chamber and travel to its bottom. As the liquid continues entering the measuring chamber, the surface of the said liquid, rises equally into the siphon as well as the chamber.
As the liquid reaches the different pins (item 4 figure 6) it causes conductivity between the said pin and the ground pin (item 30 figure 6). This conduction is sensed and translated into level and volume data by the electronic board (item 13, figure 3). In this case there are 7 pins and a ground pin. Each pin is set to 0.2 mm of rainfall at the funnel or 2 ml of volume of water in the measuring chamber. Therefore, the siphon would be placed at a height where the self-siphoning would occur at 14 ml of volume of liquid. The pins would sense 12 ml as the liquid is rising. The final 2 ml would be sensed by the electronics as the liquid fully exits the measuring chamber, and pin 4 of figure 6 is exposed. Due to this the electronics know siphoning has occurred and records the final 2 ml. As mentioned above other sensors could also be used to measure other characteristics of the said liquid. As more liquid continues to enter the measuring chamber it continues rising equally inside and outside the siphon until it reaches the end of 01 in figure 1 (figure 1 ¨ 12) and the end of sector 1 in figure 2. This is identified as item 2 in figure 2 and item 31 in figure 6. As the liquid continues to rise, the level increases on the outside of the siphon. Due to surface tension of the liquid and natural adhesion to the roughed up (item 1 figure 2 and detail 1 figure 2) inside surface and adhesion

-15-to the surface marked item 2 figure 2, the inside liquid remains at the same height for a very short period of time, even though the liquid outside the siphon continue to rise. As it increases past the top of the outside of siphon the liquid plugs hole 34 figure 6 (item 5 figure 2). A pressure difference between the liquid's two surfaces occurs. The pressure difference will increase until it becomes large enough to cause the liquid at item 31 figure 6 and item 1 figure 2 to dislodge, causing the liquid to move quickly up the siphon into areas 32 and 33 of figure 6 (also 7 and 8 of figure 2) with a kick.
This kick assures siphoning. The level of liquid where this occurs is repeatable within 5%. Bernoulli's Principle states that as the speed of a moving fluid increases, the pressure within the fluid decreases. Also, when non-compressible liquid travels through a large diameter pipe or tube to a smaller diameter pipe or tube the pressure decreases and the velocity increases. The formula is as follows:
2 Pa+ 1 /2pva+pgha=Pb+1/2pvb2+pghb Where, a = the first point along the pipe b = the second point along the pipe P = static pressure in newtons per meter squared

-16-p = density in kilograms per meter cubed v = velocity of liquid (meters / second) g = gravitational acceleration in meters per second squared h = height in meters Therefore, as the liquid travels past item 31 figure 6, into area 32 and the siphon tube becomes smaller causing the liquid to increase in velocity. To that velocity is added the kick the liquid received from the pressure difference in the liquid's surface differences. A small amount of liquid will travel up hole figure 6 (item 5 figure 2) making this hole invisible to the rest of the liquid as it siphons. Hole 35 figure 6 (item 6 figure 2) is so small that it is not sensed or felt by the high velocity liquid as it travels past it. As discussed above Bernoulli's Principle states that any liquid traveling through a pipe or tube abides by the following law:
P+112pv2+ pgh=constant Where, P = the pressure of the fluid, p = density of fluid,

-17-h =its height, v =its velocity, and g = the gravitational acceleration.
This formula assumes that the liquid is incompressible and that it suffers no friction as it moves through the pipe. The use of a single value for v (velocity) in Bernoulli's law indicates that it assumes that every portion of the liquid moves at the same velocity. That is clearly not the case: the part of the liquid that is in direct contact with the inner siphon wall will move slower than the center. This velocity difference is dependent by the said liquid's viscosity.
Poiseuille's law also influences the operation of the siphon. As per Poiseuille's law the flow of all non-turbulent liquids traveling through a tube or pipe will be laminar. The liquid that touches the walls of the siphon, as it travels through it, is most affected by friction. The friction is least at the center of the siphon tube. Therefore, an accumulation of laminas will occur. The liquid in the center lamina travels proportionally faster than the liquid belonging to the lamina touching the inner wall of the siphon. Each lamina will flow through the siphon as described by the Poiseuille's law, stating that the flow rate (F = volume of fluid flowing per unit time) is proportional to the

- 18 -pressure difference Ap between the ends of the siphon and the fourth power of its radius r.
npr 4 F= ________________________________________ Where, 1= the length of the siphon and It = coefficient of viscosity, a constant for the liquid that is being passed.

The areas where the greatest amount of resistance to flow in the siphon, from greatest to least, is the area that is roughed up as per area 1 figure 2, the lip that is created by item 2, figure 2, and item 31 figure 6, and the two holes items 34 and 35 figure 6 (items 5 and 6 figure 2) and the inner walls of the siphon. During siphoning these areas is where the liquid stays the longest time. This phenomenon allows the liquid to pass the two holes (items 34 and 35 figure 6 (items 5 and 6 figure 2)) without affecting the siphoning process at this period in time. As the measuring chamber (item 36 figure 6) empties, air is introduced into the mouth of the siphon (item 37 figure 6). As well, the mouth of the siphon sits inside a cavity (item 7 figure 5, and item 27 figure 6).
This cavity is purposely stepped. As air is introduced into the siphon the cavity's step will initiate and increase turbulent flow into the siphon. The last moment of laminar flow will occur just at the introduction of air. As air travels through the siphon the liquid in front of it is still affected by laminar flow. In this

-19-last cycle of laminar flow, the liquid at the very center of the siphoning tube will exit quicker than that at the inner walls. The liquid in the areas of most resistance will commence collapsing towards the center of the siphon and mixing with the inrush of air. Air will start coming also into the siphoning tube from the two holes items 34 and 35 figure 6 (items 5 and 6 figure 2).
Momentum, and due to the siphon being made of Teflon PTFE which has a very low coefficient to friction, allows most of the liquid left in the siphon to exit from the siphon via opening 38 figure 6. A small amount will flow back into the measuring chamber via opening 37 figure 6, and rest in cavity 27, figure 6. If any bubbles are left behind in the siphon, they will also exit via opening #

and 38 figure 6 due to gravity and air coming from holes # 34 and 35 of figure 6 defusing the pressure / suction between the bubbles and the incoming new liquid. At worst case bubbles would be left behind such that it would obstruct holes 34 and 35 of figure 6. In this situation, in the next siphoning cycle, liquid enters the measuring chamber via the funnel, allowing liquid to travel up the measuring chamber and in the siphon. This would create pressure forcing the bubbles to be pushed past holes 34 and 35 figure 6. Gravity would then pull the said bubbles out from opening 38 figure 6 while holes 34 and 35 figure 6 would allow equalization in pressure, clearing the siphon, and guaranteeing that siphoning will always commence at the same level of liquid in the measuring chamber. Cavity 27 figure 6 is small enough so that the volume of

- 20 -liquid left behind after the first siphoning cycle is still well within a small error and compensated by the microprocessor in the electronics. The low coefficient of friction contributed by the Teflon PTFE siphon tube assists in the siphoning cycle having a high velocity, allowing the measuring chamber to be emptied fast and be able to retain, without the aid of the microprocessor, 95%

or better measuring accuracy. The microprocessor raises the accuracy to above 99%. The limitations to the type of liquid to be analyzed would be if the said liquid were so thick that it cannot flow easily through the siphon or the debubbling tube. The other limitation is liquids that are highly acidic and may damage the material that make up the invention.

- 21 -

Claims

The embodiment of the invention in which exclusive property or privilege is claimed are defined as follows:

1. Apparatus for measuring the rate and amount of rainfall, as well, it can be used to measure rate and amount of any liquid that is passed through it, and the said apparatus is of significant improvement to Canadian patent # 02157943, using a siphon to empty the measuring chamber and having a solid-state level sensing device comprised of:
a) a funnel attached to a bent tube, the latter identified as a debubbling tube, which brings the liquid to be measured to the side and inside of the measuring chamber quickly, while removing any bubbles, and not causing any disturbance to the previous collected liquid.
b) a measuring chamber receives liquid from said debubbling tube where the said liquid is accumulated to a predetermined level, upon which an improved siphon from Canadian patent #
02157943, causes a self-siphoning action, and causes the chamber to empty. The said chamber also houses an improved from Canadian patent # 02157943 liquid level-sensing device.

c) an improved from Canadian patent # 02157943 level sensing device with conductive noncorrosive sensors set at various levels such that the liquid's level can be measured incrementally.
d) a holder able to hold in place the siphon and the level sensor such that it allows the removal and replacement of the said siphon, level sensor and holder as one unit, from the measuring chamber safely and repeatedly without affecting the setup or calibration of the invention and is held in place in the measuring chamber by a nut.
e) an inverted "J" siphon which is an improvement from Canadian patent # 02157943, placed in the above measuring chamber, such that a predetermined level of liquid is repeatedly siphoned.

2. Apparatus as defined in claim 1 such that the tube from the funnel, known as the debubbling tube, has a bend used to dampen the speed of the measured liquid, and directs the said liquid unto the wall of the measuring chamber, and the portion of the said tube touching the wall of the measuring chamber consists of two cuts of different angles, one above and one below, such that where those two angles meet, touch the said measuring chamber walls. This allows the said liquid to spread across an area of the said measuring chamber's wall, so that the said liquid may travel into the said measuring chamber without bubbles and without disturbing previous collected liquid.

3. Apparatus as defined in claim 2 the said debubbling tube is made of material such that liquid flows through it quickly.

4. Apparatus as defined in claim 2, the described debubbling tube, is an improvement to Canadian patent # 02157943, whereas as defined in claim 2, description as well as diagrams of the said Canadian patent # 02157943, the said tube comes straight from the funnel and ends at a distance where incoming liquid will create disturbances and bubbles on previous collected liquid, such that it would disrupt siphoning and give false readings on the level sensor. The tube described in claim 2 of this application effectively eliminates the said problems.

5. Apparatus as defined in claim 1 with a level sensor having stainless steel insulated rods with its tips exposed such that the exposed area touches the liquid in the measuring chamber. The said rods run parallel to the tube but not touching it. The said rods are set at different heights to correspond to different fluid levels to sense that level. This is an improvement to Canadian patent # 02157943 the insulation prevents droplets of water that may accumulate on the pins causing shorting to each other creating false readings.

6. Apparatus as defined in claim 5 having a level sensor connected to an electronic circuit with a microprocessor detecting said water level or / and flow and calibrating the system at every siphoning cycle. This is an improvement to Canadian patent # 02157943, were as the error would accumulate during the period of rainfall and at times carried over to the next period of rainfall.

7. Apparatus as defined in claim 1 with a measuring chamber that has a stepped cavity in its floor whereas two depths are created in the said cavity. Whereas the short leg of the siphon sits on the upper portion of the step in the cavity. This is an improvement to Canadian patent #
02157943 where in this type of cavity more turbulence is created near the end of the siphoning cycle inducing more air into the siphon which is conducive to ending the cycle quick.

8. Apparatus as defined in claim 1 having a siphon such that:
a) improvements to Canadian Patent 02157943 automatically start and stop siphoning process by taking advantage Bernoulli's Principle, Poiseuille's Law, and siphoning principles.

b) apparatus as defined in claim 8a the inside diameter of the siphon is varied at predetermined sections.
c) apparatus as defined in claim 8a where the opening of the short side of the inverted J siphon's diameter is widened, roughed, and comes to an edge.
d) apparatus as defined in claim 8a where the inside curve has been made much rounder than the one in Canadian Patent 02157943 so, as to not impede the siphoning action.
e) after every siphoning cycle the siphon is clear of any bubbles due to small holes placed in predetermined locations on the siphon.
f) the siphoning tube is made of material that has a percentage water absorption factor of less than 0.05% and a very a low coefficient of friction so, as to not impede the siphoning action.

9. An apparatus as defined in claim 7 whereas the material used has a percentage water absorption factor of less than 0.05% and a very a low coefficient of friction.