Patent Application
20090158836
The present invention relates to measuring materials being dispensed and more particularly to measurements which may not be detectable by the user.
Measurements of materials being dispensed is known in the art. For example, magnets and Hall effect sensors have been used to indicate qualitative dispensing. For example, medication compliance monitoring is shown in US 2003/0089733 A1, dispensing of a predetermined volume of liquid is shown in GB2087839 A, U.S. Pat. No. 4,934,566 shows portion monitoring based upon a slidable control stem, and U.S. Pat. No. 6,360,181 B1 shows toilet tissue usage data collection. Generally, these references rely upon the proximity of the Hall effect sensor and magnet to indicate a change in state or in component operating position. Such a change is then related to the amount of material dispensed.
However, none of these attempts deals with the problems which occur when the amount of material being dispensed changes as a function of time and usage of that dispenser. For example, a pressurized container, such as one containing propellant dispensed air freshener, will dispense less material as depletion of the propellant occurs, due to less pressurization of the material to be subsequently dispensed. Further, a long continuous burst of dispensing will release a different amount of product than several quick bursts having the same cumulative dispensing time.
Additionally, when using a pump-type dispenser, such as a squeeze trigger liquid fabric refresher, partial pulls of the trigger will typically result in only partial dispensing of the pump charge. This causes less material to be dispensed, dependent upon the trigger stroke.
However, accurate measurement of material to be dispensed requires the factors be considered. Furthermore, the measurement should occur in a matter not readily detectable to the user or which does not interfere with normal usage patterns.
In one embodiment the invention comprises a device for quantitatively measuring an amount of a material dispensed. The device comprises a reservoir for holding a material therein, a dispensing orifice for dispensing material contained in said reservoir, and a dispenser for dispensing the material from the reservoir through said orifice. The dispenser has an actuator movable relative to said reservoir and a member which is stationary relative to said dispenser. A Hall effect sensor is disposed on one of said dispenser and said stationary member, and a magnet is disposed on the other of said dispenser and said stationary member, whereby relative movement between said magnet and said Hall effect sensor produces a signal in response to said movement. The signal is correlatable to a quantity of material dispensed from said reservoir. The signal may be correlatable to the quantity of material being dispensed from the reservoir throughout dispensing of substantially all of the material contained in the reservoir.
All patents and patent applications cited herein are incorporated herein by reference.
FIG. 1 is a perspective view of an aerosol container according to the present invention.
FIG. 2 is a sectional view, taken along line 2-2 of FIG. 1
FIG. 3 is a perspective view of a trigger type pump sprayer according to the present invention.
FIG. 4 is a perspective view of the spray head of the sprayer of FIG. 3, shown in cutaway.
FIG. 5 is a perspective view of a screw thread/piston delivery device according to the present invention.
FIG. 6 is a sectional view taken along line 6-6 of FIG. 5.
FIG. 7 is a performance curve showing the relationship between trigger displacement and dispensed material for a commercially available aerosol product.
The device comprises a reservoir for holding a material therein. The reservoir may be fluid tight, if the material to be dispensed is a gas, liquid or is mixed with a gaseous propellant. The reservoir may be mounted in any desired relationship with respect to an dispensing orifice for dispensing the material to its desired end use.
The device further has a dispenser for dispensing the material from the reservoir through the orifice. Various types of dispensers are known, such as threaded screw drives for advancing a piston as occurs with many antiperspirants, a pump as occurs with many cleaners, a pressure release valve as occurs with many air fresheners and shaving creams, a lid which opens to allow manual access to and retrieval the product as occurs with wet wipes, a flexible squeeze package as occurs with toothpaste tubes, a resealingly openable bag as occurs with food storage, a walled container having a slider to open/close a lid as occurs with food storage; etc. Suitable dispensers may be made according to the teachings of commonly assigned patents: U.S. Pat. Nos. 4,122,978; 5,000,356; 4,865,231; Des. 393,999; 6,139,185; 6,149,304; 6,164,821; 6,325,239 B2; 6,394,299 B1; 6,722,520 B2 and 6,981,658 B2.
Referring to FIGS. 1 and 2, a first embodiment of the invention comprises a method and device for measuring propellant dispensed sprays. Exemplary sprays include insecticides, perfumes, paints, cleansers, topical medicaments, antiperspirants, hair sprays, room air fresheners, etc. The specific example below will be described with reference to Febreze Air Effects air freshener, although one of skill will recognize the invention is not so limited.
The dispenser may have an actuator movable relative to the reservoir or other portions of the device and a member which is stationary relative to the movable actuator. The movable actuator may be a trigger which functions as a pump, a dial which advances a piston along a screw thread, a lid which opens by pivoting about hinges, or a trigger or button which functions to open a pressure release valve, as illustrated, etc.
A Hall effect sensor may be disposed on one of the movable actuator or stationary member. The Hall effect sensor measures voltage on the opposite sides of a sheet of conducting or semiconducting material in the form of a Hall element, also referred to as a van der Pauw element. An electric current flows through the Hall element. The electric current is created by a magnetic field applied perpendicular to the Hall element.
The magnet may be disposed on the other of the movable actuator and stationary member, whereby relative movement between the magnet and Hall effect sensor produces a signal in response to movement of the movable actuator. While either the magnet or Hall effect sensor can be mounted on either component, as noted above, it may be desirable to mount the magnet on the moving actuator and the Hall effect sensor on the stationary member. This allows the wires connecting the Hall effect sensor to be held in position without significant movement and potentially becoming loose. For many geometries, this configuration also makes it easier to prevent the use of the measuring device from interfering with the normal product usage and corrupting the data.
The signal produced by the Hall effect sensor is typically correlatable to a quantity of material dispensed from the reservoir and precise. The signal may be correlatable to the quantity of material being dispensed from the reservoir throughout dispensing of substantially all of the material contained in the reservoir, or throughout only the first portion, last portion or any intermediate portion of the material being dispensed. The signal from the Hall effect sensor is related to the quantity, as measured in mass, of material dispensed through a functional relationship. The mass of material dispended may be converted to volume, using the material density, if desired.
The functional relationship may be empirically developed, developed through computer modeling, etc. The device may be set up, as described above to record the output in volts from the Hall effect sensor. The output may be recorded in any convenient format, such as a spreadsheet, as is well known in the art. The material is dispensed and the reservoir weighed after each dispensing incident. The dispensing may include both full and partial actuations of the actuator. For example, in a trigger type dispenser, the measurements may account for both full and partial pulls of the trigger.
The output may be recorded as a function of the resulting weight. A functional relationship may be interpolated from the discrete data points of each dispensing cycle. The relationship may be developed by noting the starting point of the actuator, the ending point of the actuator during a dispensing cycle, then subtracting. The two positions to yield a stroke. It is to be noted that the amount of material dispensed for a particular magnitude of partial stroke may depend not only on the magnitude of the stroke, but also upon the position of the stroke where that magnitude occurs. A partial stroke in one position may cause spritzing, whereas a partial stroke of the same magnitude in a different position may yield a nearly full dose.
Of course, one of skill will recognize the functional relationship may be maintained as a curve, as a lookup table, etc. The functional relationship may be output in graphical or visible form or may be maintained on computer and not seen by the user.
This procedure allows for the functional relationship to be maintained remote from the measuring device. Remote maintenance allows the device to be used in its normal fashion, and the data downloaded later. Such subsequent downloading may allow the functional relationship to be incorporated and the dispensing measurements to be determined at such later time as may be convenient for the user.
Referring to FIG. 7, in operation, as one dispenses material under the pressure differential provided by the propellant, there multiple pulls on the trigger occur. The trigger pulls may be from the fully closed position to the fully open position, from the fully closed position to a partially open position, from a partially open position to the fully open position, from the fully open position to a partially open position, from a partially open position to a fully closed position and various combinations thereof.
The pulls between the various positions may be recorded and thereby correlated to the amount of material dispensed through the functional relationship. Additionally, the duration, time and/or date of the Hall effect actuation responsive to the trigger pull may be recorded or downloaded for later analysis.
Referring to FIGS. 3-4, the invention may be used with a trigger pump sprayer. Such a sprayer may have a pump actuated in known fashion by the trigger. The functional relationship may be derived to yield the amount of material dispensed from the reservoir in response to various full or partial pulls of the trigger, for a particular fill level of the reservoir.
If desired, a tilt sensor may also be incorporated into the device. The tilt sensor may be used to determine if the reservoir was tipped off-center during dispensing. If so, less material may be dispensed from the reservoir and the results may not tally with the functional relationship, as expected. For example, upon tilting at the end of a dip tube, if present, may not be immersed in the material to be dispensed.
One of skill will recognize that the functional relationships derived for the embodiments of FIGS. 1-4 will be tailored to the specific geometry, propellant pressures, size, pump characteristics, etc. of the device under consideration. Additionally, the functional relationship will be specific to a particular, material under consideration. If the rheology or material properties should change, the functional relationship may be adjusted accordingly. Additionally, the functional relationship may be tailored to each specific magent/Hall effect sensor combination, as each component may have its own unique characteristics and to account for any variations in positioning such components on the.
The embodiments shown in FIGS. 1-4 illustrate a magnet incorporated into and disposed beneath the trigger. This provided the advantage that the entire measurement may be conducted invisible to the user. The measuring system is lightweight and small enough that a user may not notice and change the ordinary dispensing habits. Of course, one of skill will recognize the invention is not so limited. The illustrated positions of the magnet and Hall effect sensor may be reversed. Either or both components may be placed in different positions on the device, so long as the relative proximity therebetween, and hence a signal, can be detected in response to dispensing of materials from the reservoir.
Referring to FIGS. 5-6, the invention may be used with a screw thread device used to drive a piston, as is common with antiperspirant/deodorants. The piston is driven axially along a screw. The screw has a longitudinal axis coincident the center of the screw and parallel to the dispensing direction. Relative rotation between the screw and a threaded nut advances the piston in the longitudinal direction.
Longitudinal advance of the piston may dispense the material contained in the reservoir of this device by extrusion through one or more dispensing orifices. Such dispensing may be accomplished by rotating the screw/nut about the longitudinal axis. Rotation of the screw may occur through manually grasping a dial disposed external to the device. The dial is rotated perpendicular to and about the longitudinal axis.
A magnet may be placed on one of the dial and stationary components of the device. If desired, the magnet may be annularly shaped, circumscribe the longitudinal axis and/or be disposed perpendicular thereto. Alternatively, a single magnet disposed radially outboard of the dial may provide a more distinct change in signal strength as it advances towards and away from the Hall effect sensor. Rotation of the magnet with the dial, or Hall effect sensor if mounted on the dial, produces a signal which can be correlated to advance of the piston. Advance of the piston is then correlatable to the amount of material dispensed.
The present invention may also be used to measure opening of and access to storage bags (not shown), as are commonly used for storing food leftovers. Such food storage bags have a seal formed by a track having complementary engaging portions. One of the Hall effect sensor and magnet may be disposed on each side of the bag. Upon opening, a change in proximity therebetween may be noted and one will know the contents of the bag were accessed or additional materials were added to the bag. Thus, the present invention is usable with a reservoir having generally flaccid walls.
Likewise, the present invention may be used with a reservoir having rigid walls (not shown) as are commonly used to contain wipes, tissues, etc. For example, a generally parallelpideally shaped container having a lid may be utilized. The container may be upright, generally flat or of any desired shape/geometry. The container may have a lid which can be closed to seal the contents therein and opened to access the materials therein for dispensing, as illustrated by commonly assigned U.S. Pat. Nos. 4,979,613 and 5,516,001. The lid may be hinged, removable, etc. to reveal the orifice through which materials may be dispensed. A Hall effect sensor and a magnet are placed on the lid and sealing surface, respectively or vice versa. A change in the proximity therebetween will be detected and indicate access to the materials in the reservoir, or restocking of the reservoir, has occurred.
Additionally, the device of the present invention can be used to determine the opening and closing of shades used to cover openings, such as windows. Exemplary shades are opened and closed using a drawstring as shown by commonly assigned U.S. Pat. No. 6,640,867 B1.
One of skill will recognize the invention described and claimed herein may also be used to monitor habits of using household products. For example the magnet/Hall effect sensor combination cited herein may be used for monitoring placement of a toilet seat, opening/closing of a refrigerator door, opening/closing of a medicine cabinet door, or other aspects of a daily routine.
The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value.
All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention. To the extent that any meaning or definition of a term in this written document conflicts with any meaning or definition of the term in a document incorporated by reference, the meaning or definition assigned to the term in this written document shall govern.
While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.
