Abstract
A liquid dispenser comprising a liquid pump. The liquid pump comprises a first liquid inlet configured to allow the introduction of a first liquid into a mixing chamber; a second liquid inlet configured to allow the introduction of a second liquid into the mixing chamber; an outlet valve configured to regulate the release of a mixed liquid from the mixing chamber, the mixed liquid being a blend of the first liquid and the second liquid; and a reciprocating member configured to effect a reciprocating movement along a longitudinal axis, the reciprocating member being configured to regulate the aperture of the outlet valve. The liquid dispenser comprises a piezoelectric detector arranged in such a way that when the liquid pump generates a shockwave, the shockwave is detected by the piezoelectric detector, the piezoelectric detector generating a voltage peak which is a function of the shockwave.
Claims
1. A liquid dispenser comprising: a liquid pump, comprising: a first liquid inlet configured to allow introduction of a first liquid into a mixing chamber, a second liquid inlet configured to allow introduction of a second liquid into the mixing chamber, an outlet valve configured to regulate release of a mixed liquid from the mixing chamber, the mixed liquid being a blend of the first liquid and the second liquid, a reciprocating member configured to effect a reciprocating movement along a longitudinal axis, the reciprocating movement alternately comprising a first movement and a second movement opposite the first movement, the reciprocating member being configured such that the outlet valve closes when the reciprocating member completes the first movement and such that the outlet valve opens when the reciprocating member completes the second movement, and a liquid outlet configured to allow release of the mixed liquid when the outlet valve is open; and a piezoelectric detector arranged in such a way that when the liquid pump generates a shockwave, the shockwave is detected by the piezoelectric detector, the piezoelectric detector generating a voltage peak which is a function of the shockwave.
2. The liquid dispenser of claim 1, wherein the liquid pump is configured to generate a first shockwave when the reciprocating member completes the first movement, the piezoelectric detector thus generating a first voltage peak, and wherein the liquid pump is configured to generate a second shockwave when the reciprocating member completes the second movement, the piezoelectric detector thus generating a second voltage peak, such that the piezoelectric detector counts a working cycle when it generates either a first voltage peak or a second voltage peak.
3. The liquid dispenser of claim 2, wherein the piezoelectric detector comprises a positive voltage filter configured to filter a positive voltage peak which is equal to or lower than a positive predetermined voltage threshold, the first positive predetermined voltage threshold being a positive number, and where the piezoelectric detector comprises a negative voltage filter configured to filter a negative voltage peak which is equal to or greater than a negative predetermined voltage threshold.
4. The liquid dispenser of claim 3, wherein the positive predetermined voltage threshold is 0.01 Volts and the negative predetermined voltage threshold is −0.02 Volts.
5. The liquid dispenser of claim 3, wherein the positive voltage filter and the negative voltage filter are configured to filter any voltage within a predetermined filtering time triggered by a voltage peak not filtered by the positive voltage filter or the negative voltage filter.
6. The liquid dispenser of claim 5, wherein the predetermined filtering time is 100 milliseconds.
7. The liquid dispenser of claim 5, wherein the piezoelectric detector is configured to count a working cycle when a voltage peak not filtered by the positive voltage filter or the negative voltage filter is generated.
8. The liquid dispenser of claim 1, wherein the piezoelectric detector is disposed substantially perpendicularly to the longitudinal axis.
9. The liquid dispenser of claim 1, wherein the liquid pump comprises a dosage adjuster movable with respect to a mixing chamber outer housing, the dosage adjuster being configured to regulate a distance covered by the reciprocating member along the longitudinal axis in the first movement and the second movement, thereby regulating an amount of liquid released through the liquid outlet during a single reciprocating movement.
10. The liquid dispenser of claim 9, further comprising a printed circuit board (PCB) integral with the mixing chamber outer housing and a coiled target which is configured to move as a function of the movement of the dosage adjuster, the coiled target being configured to determine a relative position between the dosage adjuster and the mixing chamber outer housing, thus determining the amount of liquid released through the liquid outlet during a single reciprocating movement.
11. The liquid dispenser of claim 10, further comprising a controller electrically connected to the piezoelectric detector.
12. The liquid dispenser of claim 11, wherein the controller comprises a display unit configured to display information of the liquid dispenser.
13. The liquid dispenser of claim 11, wherein the controller is configured to be connected to a remote device.
14. The liquid dispenser of claim 11, wherein the controller is electrically connected to the PCB.
15. The liquid dispenser of claim 14, wherein the controller is configured to determine the amount of liquid released through the liquid outlet within a time period based on: a number of working cycles counted by the piezoelectric detector within the time period, and the amount of liquid released through the liquid outlet during a single reciprocating movement determined by the coiled target.
Description
(1) These and other features and advantages of the invention will become more evident in the light of the following detailed description of preferred embodiments, given only by way of illustrative and non-limiting example, in reference to the attached figures:
(2) FIG. 1 shows a cross section of a liquid dispenser during an instant of an initial first movement.
(3) FIG. 2 depicts a cross section of the liquid dispenser during an instant of a second movement.
(4) FIG. 3 illustrates a cross section of a liquid dispenser during an instant of a first movement subsequent to the initial first movement.
(5) FIG. 4 depicts the detection of voltage peaks by a piezoelectric detector during a given time period.
(6) FIG. 5 represents a dosage adjuster for the liquid dispenser of FIGS. 1 to 3.
(7) FIG. 6 is a perspective view of the liquid dispenser of FIGS. 1 to 3 seen from outside.
(8) FIG. 7 shows a smartphone comprising an application to display information of the liquid dispenser and to operate functions of the liquid dispenser.
(9) FIG. 1 illustrates a liquid dispenser 100 which comprises a liquid pump 1. The liquid pump 1 comprises a first liquid inlet 2 configured to allow the introduction of a first liquid 10 into a mixing chamber 4. The liquid pump 1 also comprises a second liquid inlet 3 configured to allow the introduction of a second liquid 11 from a reservoir (not represented in FIG. 1) along a supply nozzle 9 into the mixing chamber 4. The introduction of the first liquid 10 and second liquid 11 through the first liquid inlet 2 and the second liquid inlet 3 are represented with curved arrows in FIGS. 1 to 3.
(10) The reservoir may be provided with a detector configured to determine or estimate the amount of second liquid 11 stored in the reservoir. In an example, the detector comprises a sensor which determines or estimates the amount of second liquid 11 stored in the reservoir as a function of the time taken by a signal emitted by the sensor to be reflected by the second liquid 11. In another example, the detector comprises a floating element configured to float in the second liquid 11, such that the amount of second liquid 11 stored in the reservoir may be determined or estimated as a function of the position of the floating element.
(11) The liquid pump 1 comprises a reciprocating member 5 configured to effect a reciprocating movement along a longitudinal axis 21, the reciprocating movement alternately comprising a first movement and a second movement opposite the first movement, the second movement covering substantially a same distance along the longitudinal axis 21 as the first movement. In the embodiment of FIG. 1, the first movement is an upwards movement represented with arrow 22, according to the references of FIG. 1.
(12) The mixing chamber 4 of FIG. 1 comprises a first sub-chamber 41 in direct fluid contact with the first liquid inlet 2 and the second liquid inlet 3. The reciprocating member 5 is configured in such a way that the introduction of the first liquid 10 into the first sub-chamber 41 exerts a pressure on the reciprocating member 5 to initiate the first movement. The reciprocating member 5 comprises a dosage piston 51 which is configured to control the flow of the second liquid 11 into the first sub-chamber 41 through the second liquid inlet 3. In this embodiment, when the first movement is initiated, the movement of the dosage piston 51 within the supply nozzle 9 allows the introduction of the second liquid 11 into the first sub-chamber 41 through the second liquid inlet 3. In an example, the upwards movement of the dosage piston 51 during the first movement moves a seal (not represented) disposed around the supply nozzle 9 to a position in direct contact with a flange (not represented) disposed in parallel to the seal and also around the supply nozzle 9. This allows the second liquid 11 to be drawn from the reservoir into the supply nozzle 9 and, subsequently, into the first sub-chamber 41. Therefore, the first liquid 10 and the second liquid 11 blend within the first sub-chamber 41, as represented in FIG. 1 with parallel lines 12. In this example, the downwards movement of the dosage piston 51 during the second movement moves the seal to a position without contact with the flange, which allows the second liquid 11 to bypass the supply nozzle 9. Therefore, in this example, the second liquid 11 is introduced into the mixing chamber 4 only during the first movement of the reciprocating movement.
(13) The mixing chamber 4 of this embodiment also comprises a second sub-chamber 42 which is in fluid contact with the first sub-chamber 41 through an mixing chamber inner valve 43. The second sub-chamber 42 is separated from the first sub-chamber 41 by means of movable walls 44 which move integrally with the reciprocating member 5. Therefore, the first sub-chamber 41 and the second sub-chamber 42 are defined by the movables walls 44 and by a mixing chamber outer housing 8 which remains integral relative to the first liquid inlet 2 and the second liquid inlet 3. The mixing chamber inner valve 43 of this embodiment is mechanically connected to the reciprocating member 5 in such a way that the mixing chamber inner valve 43 remains closed during the first movement. FIG. 1 represents an initial first movement of the reciprocating member 5, that is, a first movement immediately after the start of the flow of first liquid 10 through the first liquid inlet 2. Since the mixing chamber inner valve 43 is closed during the first movement, and there was no liquid within the mixing chamber 4 prior to the first movement depicted in FIG. 1, the second sub-chamber 42 contains no liquid in the instant represented in FIG. 1.
(14) The second sub-chamber 42 is in fluid contact with a liquid outlet 7 through an outlet valve 6. The outlet valve 6 is mechanically connected to the reciprocating member 5 in such a way that the outlet valve 6 remains open during the first movement. In other words, the outlet valve 6 is open when the mixing chamber inner valve 43 is closed. Since the second sub-chamber 42 contains no liquid in the instant represented in FIG. 1, there is no release of liquid through the liquid outlet 7 despite the fact that the outlet valve 6 is open.
(15) In the embodiment of FIG. 1, the reciprocating member 5 is mechanically connected to the mixing chamber inner valve 43 and to the outlet valve 6 by means of a spring mechanism 52. The spring mechanism 52 is configured to flip over the mixing chamber inner valve 43 and the outlet valve 6 in the transition between the first movement and the second movement and between the second movement and the first movement. Therefore, when the first movement is completed, the mixing chamber inner valve 43 opens, the outlet valve 6 closes and the second movement starts. In the embodiments of the figures, the reciprocating member 5 comprises a plunger 53 which tops an inner wall of the mixing chamber outer housing 8 in the transition between the first movement and the second movement.
(16) FIG. 2 shows the liquid dispenser 100 at an instant of the second movement. The second movement of the embodiments of the figures is a downward movement of the reciprocating member 5 represented with arrow 23, with reference to the figures. The movable walls 44 move integrally with the reciprocating member 5 such that the volume of the second sub-chamber 42 increases during the second movement. Likewise, the mixing chamber inner valve 43 is open during the second movement, such that the blend of first liquid 10 and second liquid 11 formed in the first sub-chamber 41 during the first movement flows into the second sub-chamber 42 through the mixing chamber inner valve 43, as represented by arrow 24. Hence, in the instant of FIG. 2, both the first sub-chamber 41 and the second sub-chamber 42 contain a blend 12 of first liquid 10 and second liquid 11. In the embodiments of the figures, the diameter of the second sub-chamber 42 is greater than the diameter of the first sub-chamber 41. The resulting differences of pressures enables the downward movement 23 of the reciprocating member 5 and the moving walls 44 during the second movement. The second sub-chamber 42 reaches its maximum volume at the end of the second movement. It can be thus appreciated that the distance covered by the reciprocating member 5 in the second movement determines the volume of liquid that can be stored within the second sub-chamber 42. As depicted in FIG. 2, the spring mechanism 52 maintains the outlet valve 6 closed during the second movement.
(17) When the second movement is completed, the spring mechanism 52 of the reciprocating member 5 flips over the mixing chamber inner valve 43, which closes, and the outlet valve 6, which opens. A further first movement starts, such that the reciprocating movement 5 and the movable walls 44 move upwards as represented by FIG. 2, according to the reference of the figures. The pressure exerted by the movable walls 44 forces the blend 12 of first liquid 10 and second liquid 11 out of the second sub-chamber 42 through the outlet valve 6 during the first movement, as represented by arrow 25 in FIG. 3. The blend 12 of first liquid 10 and second liquid 11 flows along a liquid outlet 7 which enables the release of the mixed liquid from the liquid dispenser, as illustrated by arrow 13. In turn, the flow of first liquid 10 into the first sub-chamber 41 moves the reciprocating member 5 and the movable walls 44 upwards, as explained for FIG. 1, and allows the introduction of the second liquid 11 into the first sub-chamber 41 through the second liquid inlet 3 by means of the movement of the dosage piston 51 within the supply nozzle 9.
(18) In the liquid dispenser 100 of FIGS. 1 to 3, a piezoelectric detector 20 is arranged in such a way that when the liquid pump 1 generates a shockwave, the shockwave is detected by the piezoelectric detector 20. The piezoelectric detector 20 generates a voltage peak which is a function of the shockwave. In the embodiments of the figures, the piezoelectric detector 20 is disposed substantially perpendicularly to the longitudinal axis 21 and, more particularly, on an outer wall of the mixing chamber outer housing 8. Commercially available piezoelectric detectors may be employed, such as a Farnell® 1007374-FS-2513P, 80 Hz.
(19) The liquid pump 1 may generate a shockwave due to the movement or friction of one or more of its components, such as the reciprocating member 5. In particular, it has been found that the flip over of the mixing chamber inner valve 43 and the outlet valve 6 by means of the spring mechanism 52 may generate a shockwave which leads to voltage peaks having a greater absolute value than the voltage peaks generated due to the movement or friction of other components of the liquid pump 1.
(20) FIG. 4 illustrates the voltage peaks generated by the piezoelectric detector 5 within a given period of time. The piezoelectric detector 20 of FIG. 4 comprises a positive voltage filter configured to filter a positive voltage peak which is equal to or lower than a positive predetermined voltage threshold, which in the embodiment of FIG. 4 is 0.01 Volts. The piezoelectric detector 20 also comprises a negative voltage filter configured to filter a negative voltage peak which is equal to or greater than a negative predetermined voltage threshold, which in the case of FIG. 4 is −0.02 Volts. The positive predetermined voltage threshold and the negative predetermined voltage threshold are selected so as to ensure that the voltage peaks generated (i.e. not filtered) by the piezoelectric detector 20 result from the flip over of the mixing chamber inner valve 43 and the outlet valve 6 by means of the spring mechanism 52. For example, the positive predetermined voltage threshold and the negative predetermined voltage threshold filter the voltage peaks resulting from the shockwaves caused when the plunger 53 tops the inner wall of the mixing chamber outer housing 8 in the transition between the first movement and the second movement.
(21) The positive voltage filter and the negative voltage filter of the embodiment of FIG. 4 are configured to filter any voltage within a predetermined filtering time triggered by a voltage peak not filtered by the positive voltage filter or the negative voltage filter. In the embodiment of FIG. 4, the predetermined filtering time is 100 milliseconds. The predetermined filtering time is configured to avoid that the same movement or friction of a component of the liquid pump 1 (e.g. the same flip over between the mixing chamber inner valve 43 and the outlet valve 6) generates two consecutive unfiltered voltage peaks.
(22) The appropriate selection of the positive predetermined voltage threshold, the negative predetermined voltage and the predetermined filtering time may enable the piezoelectric detector 20 to count a working cycle when a voltage peak not filter by the positive voltage filter or the negative voltage filter is generated, without a need for discerning if the voltage peak is actually generated by a transition between a first (or a second) movement and a second (or first) movement (that is, by a flip over between the mixing chamber inner valve 43 and the outlet valve 6) or by any other movement or friction of a component of the liquid pump 1.
(23) In the representation of FIG. 4, the piezoelectric detector 20 detects twelve unfiltered voltage peaks which are associated to twelve working cycles C1 to C12 taking place during a time period TF. Put another way, the reciprocating member 5 executes six complete reciprocating movements during such time period TF, each comprising a first movement and a second movement. In the embodiment of FIG. 4, the reciprocating member 5 changes its speed along the longitudinal axis such that the time needed to complete a working cycle varies accordingly. More concretely, working cycles C1 to C4 are separated by a working cycle time T1; working cycles C4 to C7 are separated by a working cycle time T2; and working cycles C7 to C12 are separated by a working cycle time T3.
(24) FIG. 5 shows a dosage adjuster 30 movable with respect to an outer housing 8 of the mixing chamber 4. In the embodiment of FIG. 5, the supply nozzle 9 forms the dosage adjuster 30. The supply nozzle 9 is configured to regulate the distanced covered by the reciprocating member 5 along the longitudinal axis 21 in the first movement and the second movement in function of the relative position between the supply nozzle 9 and the outer housing 8 of the mixing chamber 4. More concretely, in the embodiment of FIG. 5, the supply nozzle 9 is configured to move helicoidally with respect to a tubular extension 81 which is integral with the outer housing 8. Therefore, the supply nozzle 9 moves linearly with respect to the tubular extension 81 when the supply nozzle 9 rotates with respect to the tubular extension 81. In order to allow for the helicoid relative movement between the supply nozzle 9 and the tubular extension 81, the supply nozzle 9 and the tubular extension 81 are respectively provided with a first thread 93 and a second thread 82.
(25) The relative movement between the supply nozzle 9 and the tubular extension 81 causes a relative movement between a dosage piston cylinder 92, which is in mechanical contact with the supply nozzle 9, and the tubular extension 81. In the example of FIG. 5, the helicoid relative movement between the supply nozzle 9 and the tubular extension 81 gives rise to a linear relative movement between the dosage piston cylinder 92 and the tubular extension 81. When the dosage piston 51 moves along the longitudinal axis 21 within the supply nozzle 9, its movement in the direction opposite the mixing chamber 4 is limited by the position of the dosage piston cylinder 92. Such limitation gives rise to a corresponding limitation in the reciprocating movement of the reciprocating member 5. As the distance covered by the reciprocating member 5 in the second movement determines the volume of liquid that can be stored within the second sub-chamber 42, the adjustment of the distanced covered by the reciprocating member 5 during the second movement enables the regulation of the amount of liquid released through the liquid outlet 7 during the first movement (i.e. when the outlet valve 6 is open) of a single reciprocating movement.
(26) The liquid dispenser 100 of FIG. 5 comprises a planar printed circuit board (PCB) 32 which is integral with the outer housing 8 of the mixing chamber 4. In particular, the PCB 32 is provided on an outer wall of the tubular extension 81. The liquid dispenser 100 of FIG. 5 comprises a coiled target 33 which is configured to move as a function of the movement of the supply nozzle 9. More concretely, the liquid dispenser 100 comprises a circumferential rim 91 which is keyed to the tubular extension 81 and which is integral with the coiled target 33. The circumferential rim 91 is in mechanical contact with the supply nozzle 9 in such a way that the helicoid movement of the supply nozzle 9 with respect to the tubular extension 81 makes the circumferential rim 91 move linearly with respect to the tubular extension 81. Therefore, the coiled target 33 follows the linear movement of the supply nozzle 9 with respect to the tubular extension 81. The coiled target 33 is thus configured to determine the relative position between the supply nozzle 9 and the tubular extension 81, which allows to determine the amount of liquid released through the liquid outlet 7 during a single reciprocating movement, as explained in the previous paragraph. In the embodiment of FIG. 4, the supply nozzle 9 (and, therefore, the dosage piston cylinder 92) is kept at the same relative position with respect to the tubular extension 81 during the time period TF, such that the amount of liquid released through the liquid outlet 7 during a single reciprocating movement is fixed to 114.225 millilitres.
(27) In the embodiment of FIG. 5, the PCB 32 comprises a coiled arrangement. The coiled target 33 and the PCB 32 comprising a coiled arrangement provide an inductive measurement which is a function of the relative position between the coiled target 33 and the PCB 32. Thus, the amount of liquid released through the liquid outlet 7 during a single reciprocating movement can be derived from such inductive measurement.
(28) The liquid dispenser 100 of FIGS. 1 to 5 comprises a controller 40 electrically connected to the piezoelectric detector 20 and the PCB 32. The controller 40 is provided on an outer wall of the outer housing 8, as illustrated in FIG. 6. The controller 40 can determine the amount of liquid released through the liquid outlet 7 within a time period based on the number of working cycles counted by the piezoelectric detector within the time period and the amount of liquid released through the liquid outlet during a single reciprocating movement determined by the relative position of coiled target 33 with respect to the PCB 32. In the example of FIG. 4, the amount of liquid released during the represented period of time is 685.35 millilitres, resulting from twelves working cycles, that is, six reciprocating movements, each reciprocating movement allowing a release of 114.225 millilitres during the first movement of the reciprocating member 5.
(29) The controller 40 may also be configured to operate other functions of the liquid dispenser 100.
(30) In the embodiment of FIG. 6, the controller comprises a display unit 41 configured to display information of the liquid dispenser 100.
(31) The controller 40 of FIGS. 1 to 6 is configured to be connected to a remote device, such as a smartphone 200 or a laptop (not represented in the figures). A screen 201 of the smartphone 200 or laptop may also display the information of the liquid dispenser 100 which can be displayed in the displayed unit 41. Likewise, the smartphone 200 or laptop may be used to operate the functions which are controllable with the controller 40 remotely from the controller 40.
(32) The smartphone 200 may include an application (App) 202 running thereon. The controller 40 may be configured to store, for example on an NFC tag, operational parameters to operate at least some of the functions of the liquid dispenser 100. Upon a user presenting the smartphone 200 to the liquid dispenser 100, the operational parameters may be downloaded to the smartphone 200 using the NFC protocol. The smartphone 200 may be configured to automatically start the App 202 upon pairing with an NFC tag. The controller 40 may be configured to store a unique identifier which corresponds to a specific liquid dispenser 100, of which there may be a large number. The identifier may also uploaded to the smartphone 200.
(33) Once the App 202 is running on the smartphone 200, and the data has been downloaded from the NFC tag, the user may, upon first pairing with the smartphone 200, access the information of the liquid dispenser 100, displayed on the screen 201 of the smartphone 200.
(34) The liquid dispenser 100 of FIG. 6 also comprises a battery 42 integrated into the liquid dispenser 100. The battery 42 is configured to provide a voltage of 5 Volts working in DC. The liquid dispenser 100 further comprises a paddle wheel (not represented) which allows manual generation of energy when no other sources of energy are available. The paddle wheel is provided upstream of the first liquid inlet 2.
