WO2015008298A1

WO2015008298A1 - Device for measuring fluid level in a container

Info

Publication number: WO2015008298A1
Application number: PCT/IN2014/000466
Authority: WO
Inventors: Ravi Ranjan
Original assignee: Kpit Technologies Ltd.
Priority date: 2013-07-15
Filing date: 2014-07-14
Publication date: 2015-01-22

Abstract

The present invention discloses a device for measuring fluid level in a container (601). The device comprises three or more guiding rods (401, 602) mounted at base of the container, a float (301, 603), and at least one resistive band (402, 604). The float configured to be supported by the three or more guiding rods in such a way that movement of the float being restricted to one degree of freedom thereby providing resistance to sloshing during the fluid level measurement, at least one resistive band attached inside the container in such a way that electrical connection being established with the float. The float moves vertically along with the guiding rods only when equal magnitude of force is applied vertically along with the three or more guiding rods in the same direction and the vertical movement of the float establishes electrical connection with the at least one resistive band and thereby determining quantity of fluid available in the container.

Description

DEVICE FOR MEASURING FLUID LEVEL IN A CONTAINER

FIELD OF THE INVENTION The present invention generally relates to field of measurement system, and more particular relates to a device for measuring fluid level in a container.

BACKGROUND OF THE INVENTION A fluid level measurement unit is a device employed in a fluid tank for indicating amount of fluid in the fluid tank. Figures 1A and 1B illustrate an exemplary conventional fluid level measurement unit. Typically, the fluid level measurement unit houses a fulcrum type arrangement, where a longer arm holds a float and a shorter arm connects to resistive bands. The float rests on the surface of the fluid in the fluid tank. With variation in the amount of fluid in the fluid tank, the position of float attached to the longer arm also varies. As the^' position of float varies, position of a switch connecting with resistive bands also varies. Based on the position of switch connecting to a particular band in response to the position of the float, the amount of fluid is displayed on a fluid level indicator. The shorter arm connects to 30 to 40 resistive bands, hence the fluid meter can display up to 40 values between a tank full to tank empty condition.

If the fuel tank is static and does not experience any motion, then fluid level measurement is easy and accurate by using the existing mechanisms. But in condition when either the tank is moving or experiences motion or any type of movement due to any other reason e.g. a fuel tank in automotive is in motion, then the phenomenon of sloshing is prominent. Due to sloshing, the fluid is not at a uniform level and keeps on abruptly changing at any given measurement point in the tank. To avoid this, the conventional fluid level indicator displays average values corresponding 4 to 5 bands out of 40, especially when the fluid in the fluid tank l experiences any type of motion. Consequently, the fluid level indicator fails to accurately display the amount of fluid in the fluid tank due to sloshing and any other movements of the fluid. Therefore there is a need of a device for measuring fluid level in a container (such as tank)that can accurately detect a fluid in the container under various circumstances. Additionally, there is a need for a low cost solution for measuring the amount of fluid in a precise unit so as to be able to display the accurate amount of fluid in a numeric quantity in various scenarios and conditions.

SUMMARY OF THE INVENTION

An embodiment of the present invention describes a device for measuring fluid level in a container. The device comprises three or more guiding rods mounted at base of the container, a float configured to be supported by the three or more guiding rods in such a way that movement of the float being restricted to one degree of freedom, at least one resistive band attached inside the container in such a way that electrical connection being established with the float, the float moves vertically along with the guiding rods only when equal magnitude of force being applied vertically along with the three or more guiding rods in the same direction and the vertical movement of the float establishes electrical connection with the at least one resistive band and thereby determining quantity of fluid available in the container. The guiding rod is made up of at least one material from a group comprises aluminum, steel, and plastic.

In an aspect of the present invention, the device comprises one of an analog meter and a digital display for displaying the specific quantity of the fluid, wherein the digital display displays the quantity of fluid in a numeric value. The float comprises three or more holes allowing the three or more guiding rods to pass through the three or more holes, having three or more corresponding bushes in order to restrict the movement of the float to one degree of freedom thereby maintaining the three or more holes on the same plane. In one aspect, the float is attached with a connector or a spring loaded connector, which slides over the resistive band corresponding to the fluid level in the container. The float is either a one piece element or multiple pieces connected together. The shape of the float is either regular shape or irregular shape. The regular shape is selected from a group comprising of a triangle, square, rectangle, pentagon, hexagon, heptagon, octagon, and circle. The float is preferable made up of a plastic material or any other suitable material known in the art.

The resistive band is placed on a vertical strip/plate in such a way that the vertical movement of the float establishes electrical connection with the resistive band. The vertical strip may be placed along the inner circumference or the outer circumference of the float or any other suitable position inside the container such that the vertical movement of the float establishes electrical connection with the resistive band. The fluid level measurement device of the invention is compatible to be installed at the time of manufacturing or be retrofitted into any application machine/device, for example, inside a vehicle.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS illustrates a conventional fluid level measurement unit.

illustrates resistive bands in the conventional fluid level measurement unit.

illustrates a top view of a device for measuring fluid level in a container according to an embodiment of the present invention, illustrates a perspective view of a device for measuring fluid level in a container according to an embodiment of the present invention. illustrates condition for change in float position according to an embodiment of the present invention.

illustrates the position of the resistive bands inside the fluid container according to an exemplary embodiment of the present invention, illustrates a float to be used in a device for measuring fluid level in a container according to an exemplary embodiment of the present invention.

illustrates guiding rods attached at the base of a container according to an exemplary embodiment of the present invention,

illustrates a process to measure the quantity of fluid in the container according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION The embodiments of the present invention will now be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the present embodiments. The size, shape, position, number and the composition of various elements of the device of the invention is exemplary only and various modifications are possible to a person skilled in the art without departing from the scope of the invention. Thus, the embodiments of the present invention are only provided to explain more clearly the present invention to the ordinarily skilled in the art of the present invention. In the accompanying drawings, like reference numerals are used to indicate like components.

The specification may refer to "an", "one" or "some" embodiment(s) in several locations. This does not necessarily imply that each such reference is to the same embodiment(s), or that the feature only applies to a single embodiment. Single features of different embodiments may also be combined to provide other embodiments.

As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless expressly stated otherwise. It will be further understood that the terms "includes", "comprises", "including" and/or "comprising" when used in this specification, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features integers, steps, operations, elements, components, and/or groups thereof. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may be present. Furthermore, "connected" or "coupled" as used herein may include operatively connected or coupled. As used herein, the term "and/or" includes any and all combinations and arrangements of one or more of the associated listed items.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The present invention describes a device for measuring level of fluid accurately in a container in various circumstances such as in a moving container e.g. fuel level measuring device in an automobile. The device for measuring fluid level comprises three or more guiding rods, a float, a vertical flat strip/plate and at least one resistive band. The float used may be of various shapes such as regular shape and irregular shape. The regular shape includes, but not limited to, triangle, square, rectangle, pentagon, hexagon, heptagon, octagon, and circle. The float can be a one piece element or multiple pieces connected together, as per the ease of assembly. The given disclosure details a two piece float, as illustrated in Figure 7, which assembles inside the container as a single float. The guiding rods have threaded ends and sit at a bottom adapter, brazed at the floor of the fluid container. The float houses bush on all four holes such that it slides on the guide together. The clearance of bush is maintained such that all the four points of the float lie in same plane at all times and in various conditions. A strip of resistive band is etched onto a vertical strip/plate. The vertical strip/plate with the resistive bands is positioned along either the inner circumference of the float or the outer circumference of the float, as illustrated in Figure 6. The vertical strip/plate with the resistive band is attached in either position either by pasting, snap or any other known mechanism.

The float houses a spring loaded connector which slides over the resistive band corresponding to the fluid level. The spacing in the consecutive resistance bands is maintained such that connector touches only one band at a time. The designed mechanism allows the travel of float only when equal force is applied on all four sides along the guiding rods and in the same direction, as illustrated in Figure 5. Due to this mechanism, the movement of float happens only in ideal and appropriate conditions when the overall fluid level rises or falls. This provides for an accurate measurement of the fluid level in a container. In all other cases, like, sloshing, irregular movement of the fluid in the container resulting in a gradient or any kind of disturbance, will not result in equal force on all the guides and in the same direction at the same time. This avoids the erroneous and inaccurate measurement of the fluid in the container. Due to the movement of the float, the connector connects to the resistance strip on resistive band and completes a circuit and the corresponding value is displayed either on an analog meter or digital display. The mechanism of the invention provides accurate measurement of the fluid and displaying it in a 'numeric value' in case a digital display is used. The meter is pre-calibrated for the fluid level corresponding to each resistive band and hence displays the numeric value of the fluid inside the container. The device of the invention can be used to measure different types of fluids, like, but not limited to, water, gasoline, fluid mixtures, etc. and the fluids placed in any container.

Figure 3 illustrates a top view of a device for measuring fluid level in a container and Figure 4 illustrates a perspective view of the device according to an embodiment of the present invention. In this embodiment, the figure discloses four guiding rods 401, a float 301 having a rectangular shape and a vertical flat strip/plate402 passing through the center of the float. The float 301 moves upward or downward based on the change in level of fluid in the container. For example, the float 301 moves upward when the fluid exerts equal force and in the same direction on the four corners of the rectangular float as shown in Figure 5. Figure 5 illustrates change in the position of the rectangular float either upward or downward according to an embodiment of the present invention. This embodiment illustrates the change in position of the float which is possible only when equal magnitudes of forces are applied in the same direction along the guiding rods. Since the shape of the float is rectangular and the numbers of guiding rods are four, the four directional forces F1 , F2, F3, and F4 are required to be applied with equal magnitude and in same directional along the four guiding rods to change the position of the float either upward or downward. During the upward and downward motion, the rectangular float is guided by the four guiding rods. Thus, the movement of rectangular float is restricted to only one degree of freedom. The one degree of freedom restricts angular movement of the rectangular float, thereby making the fluid level measurement unit resistant to sloshing phenomenon and providing for an accurate fluid level measurement.

In any other condition i.e. either one or all three forces are either of different magnitude or applied in different directions, then the float would experience a moment along the centreline which restricts the travel of float. In case of sloshing or when the container is placed at a gradient in certain conditions, the float experiences a moment and no change in position is possible until the fluid level changes. Figure 6 illustrates the position of the resistive bands inside the fluid container according to an exemplary embodiment of the present invention. In this embodiment, a device for measuring fluid level in a container is illustrated with a float 603having circular shape. Figure 6a shows a top view of the device having circular float mounted on base of a tank supported by four guiding rods 602. The figure 6a also shows a vertical stripe/p!ate604having one or more resistive band to enable the float 603 to establish electrical connection during upward or downward movement. In this figure, the vertical strip/plate with the resistive bands is positioned along the height of the inner circumference of the fluid container.

Figure 6b shows a perspective view of the device which includes a circular float 603 and four guiding rods 602 inside a container601 according to one embodiment.

Figure 6c shows the inner circumference of the float and the outer circumference of the float where the vertical strip/plate with the resistive bands may be placed and enables the float to establish electrical connection during upward or downward movement. In one embodiment, the vertical strip having resistive bands can be placed at any point along the inner circumference of the float and along the height/depth of the fluid container such that a connector on the float makes sliding contact with the resistive bands. In another embodiment, the vertical strip having resistive bands can be placed at any point along the outer circumference of the float and along the height/depth of the container such that a connector on the float makes sliding contact with resistive bands. Figure 6d shows the vertical strip/plate with the resistive bands is positioned along the height/depth of the fluid container.

In one exemplary embodiment, as the fluid level lowers, the float moves downwards, and the change in the position of the float in turn establishes connection with a different resistive band based on the level of the fluid. Each resistive band on the central rod has a different resistance value; thus, the amount of current passing through the circuit changes corresponding to each resistive band. The device is pre-calibrated for the fluid level corresponding to each band. The circuit measures the current value and provides the position of band and thus the corresponding fluid level. Accordingly, the level of fluid in a container is displayed on a fluid level indicator.

In another exemplary embodiment, the fluid level measurement device of the invention is used in an automobile to measure the amount of fuel in a fuel tank. When the fuel level lowers, the float lowers and hence, connects to a resistance band at that fluid level. The corresponding value of current is displayed either in an analogue or digital display in terms of fluid volume. Additionally, with the present device/system the fluid level can be displayed either in a continuous or a discrete format. For example, for automotive, the fuel level is pre-calibrated for different fuel tanks/vehicle models and look up tables are prepared. Based on the indication provided by the device/system, an exact amount of fluid available in the tank is displayed, whereas the conventional measuring device in the existing automobile just displays the bands or a range of fuel available in the tank. However, the device of the present invention provides for measuring fluid level and displaying the quantity of fluid in terms of the specific number of units of fuel available in the tank. For example, in a vehicle, the display unit of the device will display, number '3', when 3 liters of fuel is available in the tank, number '4.2' when 4.2 liters of fuel is available in the tank, etc. Thus, the present invention provides a low cost and accurate fluid level measuring device for measuring the amount of fluid as opposed to the existing systems. Being low cost, the device can be mounted affordably in low end and mid end cars. Additionally, this device can be installed at the time of vehicle manufacturing or may also be retrofitted into the existing vehicles. Being a low cost and an accurate measurement device, it can be conveniently retrofitted into the existing vehicles and would be especially beneficial for the low end and mid end cars. In one embodiment, the float can be either a one piece element or a multiple pieces element, connected together, as shown in Figure 7. Figure 8 shows the guiding rods fixed by tapped sleeve brazed at bottom/floor of container.

Figure 9 illustrates a process to measure the quantity of fluid in a container according to an embodiment of the present invention. At step 901 , there is a change in the level of fluid. At step 902, the float position is changed due to a change in the level of fluid. At step 903, a connector or spring loaded connector attached with the float establishes electrical connection with a resistive band corresponding to the current level of fluid. At step 904, the amount of electrical current passing through the circuit is determined. At step 905, quantity of fluid is displayed in the specific number of unit based on the determined flow of electrical current. Although the invention of the device and method has been described in connection with the embodiments of the present invention illustrated in the accompanying drawings, it is not limited thereto. It will be apparent to those skilled in the art that various substitutions, modifications and changes may be made thereto without departing from the scope and spirit of the invention.

Claims

1. A device for measuring fluid level in a container, comprising three or more guiding rods mounted at base of the container;

a float configured to be supported by the three or more guiding rods in such a way that movement of the float being restricted to one degree of freedom; and

at least one resistive band attached inside the container in such a way that electrical connection being established with the float, the float moves vertically along with the guiding rods only when equal magnitude of force being applied vertically along with the three or more guiding rods in the same direction, and

the vertical movement of the float establishes electrical connection with the at least one resistive band and thereby determining quantity of fluid available in the container.

2. The device as claimed in claim 1 further comprising one of an analog meter and digital display for displaying the specific quantity of the fluid, wherein the digital display displays the quantity of fluid in a numeric value.

3. The device as claimed in claim 1 , wherein the float comprises three or more holes allowing the three or more guiding rods to pass through the three or more holes, having three or more corresponding bushes in order to restrict the movement of the float to one degree of freedom thereby maintaining the three or more holes on the same plane.

4. The device as claimed in claim 1, wherein the resistive band is placed on a vertical strip in such a way that the vertical movement of the float establishes electrical connection with the resistive band.

5. The device as claimed in claim 1, wherein the vertical stripe with the resistive band is placed along the circumference of the float in such a way that the vertical movement of the float establishes electrical connection with the resistive band.

6. The device as claimed in claim 1 , wherein the float is attached with a connector or a spring loaded connector, which slides over the resistive band corresponding to the fluid level in the container.

7. The device as claimed in claim 1 , wherein the guiding rod is made up of at least one material from a group comprises aluminum, steel, and plastic.

8. The device as claimed in claim 1 , wherein the float is a single piece element or a multiple pieces element.

9. The device as claimed in claim 1, wherein shape of the float is one of a regular shape and irregular shape,

the regular shape is selected from a group comprises triangle, square, rectangle, pentagon, hexagon, heptagon, octagon, and circle.

10. The device as claimed in claim 1 , wherein the float is made up of a plastic material.

11. The device as claimed in claim 1 , wherein the device is compatible to be installed at the time of manufacturing or be retrofitted into an existing machine.

12. The device as claimed in claim 1 , wherein the fluid includes but not limited to water, gasoline, and fluid mixtures.