APPARATUS AND METHODS FOR MAKING BEVERAGES
Field of the Invention The present invention relates to apparatus and methods for making dπnks like espresso, cappuccino, coffee, tea, and filtered water for human consumption and enjoyment More particularly, the invention relates to apparatus and methods for removing water impurities which are oπginated from water itself or the parts of the apparatus in contact with water to produce filtered water either for direct human consumption or for use in preparing other dπnks, and for frothing milk for making milk-containing drinks like espresso, cappuccino and latte
Background of the Invention Water is a increasingly popular dπnk, and is used to brew other dπnks such as coffee, tea and espresso Water vapor or steam is used to heat and froth milk for making cappuccino, latte and other dπnks containing milk Water filtration is known to improve water taste and the taste of dπnks made from the filtered water Water filtration pitchers has been increasingly used to filter water for either direct consumption or for use with automatic dπp coffeemakers in preparing coffee Water filtration have also been integrated into automatic dπp coffeemakers by formmg a cavity at the outlet of the water reservoir for receiving a water filter cartπdge and directing the filtered water to the water heater as soon as it exits the cartπdge Such arrangement has several drawbacks First, it can not provide a supply of filtered water as quickly as required by apparatus like espresso/cappuccino machines and those disclosed in U.S Pat. 5,267,506 Second, it has low filtration efficiency because it can only use relatively large activated carbon particles to achieve the flow rate required by the automatic dπp coffeemakers Third, none of the current coffeemakers can produce filtered water for direct consumption Forth, a partially clogged water filter cartπdge will change the water flow rate through the water heaters of the automatic dπp coffeemakers, thus may cause changes in coffee temperature and taste Fifth, the water filter cartπdge provide a bed for bacteπa growth and may produce foul odor At
last, the water filter cartπdge can not remove the plastic odor and impurities in the water which result from contacting the plastic, rubber and metal parts of the apparatus U S Pat No 5,393,548 discloses a device and method for filtering impurities from the water by positioning a water filtration device between the hot water dπp outlet of an automatic dπp coffeemaker and the ground coffee in a filter This device and method resolved to some degree the fourth and sixth drawbacks mentioned above with the existing water filter systems for automatic dπp coffeemakers, but it caused additional problems including that water may overflow the top of the device and get to the ground coffee unfiltered and that the device may be covered with ground coffee and cause additional cleaning work for the consumers
Currently, none of the commercially available espresso and cappuccino machines have water filter system, although the consumers who dπnk espresso-based beverages like espresso, latte and cappuccino are normally more conscious to coffee quality and taste than the consumers who dπnk only regular coffee There is currently no known water filtration system which can be adapted to the espresso and cappuccino machines and the apparatus disclosed in U S Pat No 5,267,506 without major inventive modifications There is neither known water filtration system for producing puπfied water for producing steam for frothing milks for making milk-contaming dπnks like cappuccino and latte
Cappuccino, latte and other milk-containing dπnks are made by adding espresso into milk, or vice versa Pπor to mixing milk with espresso, the milk is frothed with a jet of steam to produce a foamy head and to heat the milk to a desired temperature The simplest frothing device consists of a steam tube havmg an oπfice at one end for producing a steam jet The espresso machine operators position the orifice just below the surface of milk and bobs the milk container up and down to inject air into the milk After enough foam is produced, the steam tube is inserted down into the milk to further heat the milk without producing more foam Here, expeπence is crucial to obtain satisfactory results because if you have the nozzle too deeply into the milk there will be no foam, if you have it too shallow it will spray milk all over
A first modified form of the frothing device, as disclosed in U S Pat Nos 4,735,133, 4,800,805, 4,945,824, and 5,335,588, has an air tube with a first end next to the oπfice of the steam tube and a second end far above the surface of milk, thus making air available to the milk near the steam oπfice even if the
oπfice is immersed in the milk The air tube is very restrictive to reduce and control the flow of air into the tube One problem aπses with this modified frothmg device in that after the milk container is full of foam or after the desired amount of foam has been produced, it is difficult to further heat the milk without producing more foam Consequently, you may have to either satisfy with a lukewarm milk or suffer a mess caused by milk overflowing A second problem with this device is that the air tube is very vulnerable to clogging by milk, dusts, etc , thus making the frothmg operation inconsistent and frustrating A third problem aπses with this device in that there are vaπous types of milk and they may require more or less air flow to achieve optimum frothing To correct the third problem, the air tube needs a valve to adjust the air flow, which makes the device complex and difficult to use
A second modified form of the frothmg device, as disclosed in U S Pat Nos 4,779,519, 4,949,631, 5,265,519 and 5,330,266, compπses a chamber having a steam inlet, an air inlet, a milk inlet and an outlet for the above three fluids The steam gushing from the steam inlet aspirates and entrains, by the ventuπ effect, the air from the air inlet and the milk from the milk inlet An air-milk-steam mixture is formed in the chamber and discharged from the outlet as an emulsion, which after collected in a container will form a foamy head on the milk There are several critical problems with such modified milk frothing devices First, the air inlet m such modified milk frothing devices must be small and is thus subject to clogging by milk and particles, which greatly reduces the reliability and increase the chance of product returns by the consumers Second, to meet the consumer needs to froth the different types of milks such skim, low fat and regular milks, to obtain different amount of foam, or to achieve different milk temperatures, these modified devices need valves to adjust the air and milk flow mto the chamber, which complicates the device and the operation At last, these modified devices are normally very noise due to the mixing of air, milk and steam in the chamber and release significant amount of steam during the frothing operation, which sometimes intimidates and confuses the operators
A third modified form of the frothing device involves a spinning blade at the end of the steam tube Steam whirls the blade like a immature turbme to break air bubbles into smaller ones to stabilize the resulting
foam This method, however, requires the operators to keep movmg the milk container downward during frothing process to ensure that the air vent in the blade attachment is just at the surface of the milk
The present invention provides apparatus havmg novel and improved means for making filtered water either for direct consumption or for use in preparing dπnks such as espresso, coffee, cappuccino and latte and for automatically frothing milk, and is aimed at solving the problems associated with the existing apparatus for making such dπnks
Summary of the Invention
In accordance with the present invention, there is provided a new apparatus and methods for making cappuccino, latte, espresso, coffee, tea and/or other dπnks for human consumption and enjoyment The apparatus compπses a cold water filter system for preparing puπfied water from a supply of water that may contain impurities either for direct consumption or for use in making dπnks such as espresso, coffee, cappuccino and latte, water heating and delivering means for heating the puπfied water and delivering the hot water and steam, a hot water filter assembly for filtering the impurities which are oπgmated either from the water itself or the parts of apparatus in contact with water, a coffee filter for receiving a supply of flavor- containing mateπal such as coffee and for allowing the extraction of the flavor-containing mateπal by the hot water therein, and/or an automatic milk frothier for automatically producing any amount of foamy head on the milk as desired by the operators of the apparatus
The cold water fiker system compπses a first containing means for receiving a supply of water which may contain impurities, a second containing means for receiving the filtered water, a water flow passageway havmg one end connected to the bottom portion of the first containmg means and the other end extended into the second containmg means, a water filter cartπdge removably mounted in the water flow passageway, an automatic valve located in the water flow passageway for automatically closing the passageway when the first containing means is removed from the second containing means and opening the water flow passageway when the first containing means is placed onto the second containing means, and discharging means such as a spigot and outlet located near the bottom of the second containing means for discharging the filtered water for either
drinking directly or preparing other dπnks The water filter cartπdge compπses a first cylindrical chamber having one end generally open and the other end made of a porous wall, a second cylindrical chamber having one end generally open and the other end made of a porous wall, snap lockmg means formed at the open end of the first cylmdπcal chamber and the porous wall end of the second cylmdπcal chamber, a space formed between the porous wall of the first and second cylmdπcal chambers after the second cylmdπcal chamber is snapped mto the first cylmdπcal chamber, and a predetermined amount of filter mateπals like activated carbon confined in the space In a modified embodiment of the cold water filter system, the first containmg means is permanently attached to the second containing means and the automatic valve is replaced with venting means connected to the second containing means The venting means releases the air trapped m the second containmg means during the water filtration and admits air into the second containing means during the discharging of the filtered water
The hot water filter assembly is located at the outlet of the brew head so that the impurities oπgmated from both water itself and from the parts of the apparatus in contact with water are removed πght before the hot water reaches the flavor-containing mateπal m the coffee filter The hot water filter assembly compπses a water filter cartπdge havmg a cartπdge inlet for receiving the hot water from the outlet of the brew head and a cartπdge outlet for discharging the filtered water mto the coffee filter, a water distπbution chamber formed between the outlet of the brew head and the cartridge inlet and encircled by an elastomer πng member to achieve a water-tight seal between the brew head and the cartridge inlet so that all the hot water from the brew head is directed into the water filter cartπdge, and a fixture for removably receiving the water filter cartπdge and for retammg the cartπdge in position to mamtam the water-tight seal between the brew head and the cartπdge inlet during the operation of the apparatus In one embodiment of the hot water filter assembly, the fixture is a compartment attached to the brew head and compπses a substantially round support base, a support side wall of a predetermined height perpendicular to the support base, and an opening for receiving the cartπdge mto the compartment In another embodiment of the hot water filter assembly, the fixture compπses a bolt formed on the brew head and dimensioned to insert mto a hole formed in the filter cartridge and a nut for lockmg the filter cartπdge in position after the filter cartπdge is inserted into the bolt
The automatic milk frothier is connected to the water heating and delivering means through a steam- supplying conduit It compπses nozzle means for transforming the steam into a steam jet, a chamber havmg an inlet port for receiving the steam jet and a fluid outlet port, means for producmg a vacuum m the chamber by the steam jet, liquid passageway means m communication with the chamber for introducing liquid mto the chamber, liquid jet means for transforming the liquid m the chamber mto a liquid jet, an arrangement that allows the liquid jet to thrust mto the liquid in a containing means thereby producmg fine air bubbles or foam in the containing means, and foam level control means for controlling the amount of foam to be produced The liquid jet means can be a small diameter conduit havmg one end connected to the fluid outlet port of the chamber and the other end directed towards the liquid in the containing means for issuing the liquid jet The foam level control means, in one embodiment of the invention, compnses a hollow cyhndπcal chamber constructed to enclose the liquid jet and adapted to be moved up and down relative to the liquid et means and, in another embodiment of the invention, compπses a fluid mlet for fluid such as air and foam, a fluid passageway for providing communication between the fluid inlet and the liquid jet and positionmg means for the operator of the apparatus to set the fluid mlet at a certam position accordmg to the amount of foam desired pπor to frothmg the liquid The foam level control means selectively introduces air to the liquid jet in the containing means, thus generating foam in the liquid in the containing means, before a desired amount of foam is been produced and introduces foam to the liquid jet, thus regenerating the foam m the liquid in the containing means, after the desired amount of foam is produced
It is an object of the present invention to provide an apparatus for making dπnks such as espresso, coffee, cappuccino, latte, filtered water, or tea for human consumption and enjoyment
It is a further object of the present invention to provide an apparatus which has a cold water filter system for makmg filtered water either for direct human consumption or for use in preparmg other dπnks like espresso, cappuccino, coffee or tea
It is a still further object of the present invention to provide an apparatus which has a cold water filter system that can instantly provide a certam amount of filtered water either for direct human consumption or for use to prepare other dπnks like espresso, cappuccino, coffee or tea
It is a still further object of the present invention to provide an apparatus for makmg dπnks like espresso, cappuccino, filtered water, coffee or tea which has a removable water reservoir and a water passageway connected to the reservoir in which a water filter cartπdge and an automatic flow valve are disposed, thus allowing the operators of the apparatus to remove the reservoir, fill it with water from a water source like a water faucet and replace it mto the apparatus without worrying about water leaking out of the reservoir and filter cartπdge
It is a still further object of the present invention to provide an apparatus which has a hot water filter assembly for removing the impurities onginated from the water itself and parts of the apparatus m contact with the water before the hot water is brought mto contact with flavor-carrymg mateπals like coffee or tea
It is a still further object of the present invention to provide an apparatus for makmg drmks like espresso and cappuccino which has a hot water filter assembly located on the brew head that allows consumers to easily mount and remove the disposable water filter cartridge
It is a still further object of the present invention to provide an apparatus which has a novel device for automatically frothmg milk which requires little maintenance and trouble free
It is a still further object of the present invention to provide an apparatus which has a novel device for automatically frothmg milk which requires no air mlet holes or channels which are easy to be clogged by milk or particles
It is a further object of the present invention to provide an apparatus which has a novel device and method for frothmg milk m an essentially automatic manner so that the quality and quantity of the foam as well as the temperature of the frothed milk are essentially independent of the operator's skill
It is a still further object of the present invention to provide a novel attachment for frothmg milk which does not reqmre small, easy-to-clog holes as seen in existing πulk frothmg attachment m espresso/cappuccmo machines
It is a further object of the present invention to provide an apparatus which has a novel device that can froth milk essentially automatically and can indicate to the operators when the milk temperature is ready
These and other objectives and advantages of the present invention will become apparent from the following descπption of the preferred embodiments, taken together with the accompanying drawings
Descπption of the Drawing
The accompanying drawing illustrates diagramatically non-limitative embodiment of the invention, as follows
FIG 1 is a schematic diagram showing the constitution of an apparatus for makmg dπnks such as espresso, coffee, cappuccmo, or filtered water m accordance with the present invention,
FIG la is a sectional view of the bottom 38 of outlet chamber 23 of the cold water filter system 11 shown in FIG 1 showing the prevention stems 44,
FIG lb is a sectional view of the hot water filter system shown in FIG 1, taken along the hne ll-II,
FIG 2 is a sectional elevation view of another embodiment of the cold water filter system 11 shown in FIG 1,
FIG 3 is a sectional elevation view of another embodiment of the cold water filter system 11 shown in FIG 1,
FIG 4 is a sectional view along line IV-IV of FIG 3,
FIG 5 is a sectional elevation view of another embodiment of the automatic milk frothier 14 shown m FIG 1,
FIG 6 is a sectional view along l e VI-VI of FIG 6,
FIG 7 is a sectional elevation view of another embodiment of the automatic milk frothier 14 shown in FIG 1,
FIG 8 is a sectional elevation view of another embodiment of the automatic milk frothier 14 shown m FIG 1,
FIG 9 is a sectional elevation view of another embodiment of the hot water filter assembly 16 shown in FIG 1
Detailed Descnptiσn of the Preferred Embodiments
FIG 1 shows certam parts of an apparatus 10 for makmg dπnks such as espresso, latte, cappuccmo, coffee, tea, filtered water, or any combination of them which embodies one form of the present mvention Only those parts of the apparatus are shown which are necessary for full understandmg of the mvention For example, the housing for the apparatus 10 and the parts for connecting the energy-consuming units of the apparatus to an energy source such as an electrical outlet have been omitted for the sake of clarity and simplicity All such parts which are not specifically shown but necessary in order to render the apparatus fully operative can be similar, analogous or identical to the corresponding parts heretofore conventionally known and used in existing apparatus for makmg dπnks such as steam espresso machines, pump espresso machines, water filter devices, and automatic dπp coffeemakers
Apparatus 10 compπses a cold water filter system 11, a water heating and delivering system 12 connected to the cold water filter system through conduit 13, an automatic milk frothier 14 connected to the water heating and delivermg system through a steam conduit 15, a hot water filter assembly 16 connected to the water heating and delivermg system through a hot water conduit 17, a flavor extraction system 18 havmg a coffee filter 19 for receiving a supply of flavor-carrying mateπal 32 and a filter holder 20, and a receptacle 26 below said flavor extraction system for receiving the flavor-containing water from the filter holder The water heating and delivermg system 12 can be, but not limited to, the water heater and pump used m pump espresso machines, the water heating and steam pressure generation system m steam espresso machines, the water heating and delivering system used m automatic dπp coffeemakers, and the water heating and delivermg system disclosed m U.S patent 5,267,506 The flavor extraction system 18 can be, but not limited to, the coffee filter assembly m pump espresso machines, steam espresso machines, and automatic dπp coffeemakers
Cold water filter system 11 compπses a first container 21 for receiving unfikered water 34, a second container 24 on which the first container is removably mounted for receiving the filtered water 37, a water flow passageway chamber 23 havmg one end connected to the bottom portion of the first container 21 and another end extended mto the second container 24, a water filter cartridge 22 removably mounted m the chamber 23 for filtering the water in the first coπtamer, an automatic valve 25 located at bottom plate 38 of
the chamber 23 for automatically shutting off the water flow through the water flow passageway chamber when the first contamer is removed from the second contamer and openmg the water flow when the first contamer is mounted on the second contamer, a spigot 27 located near the bottom 28 of the second coπtamer for dispensing the filtered water to a cup or other containers for direct consumption, and an outlet 29 located at bottom 28 for introducing the filtered water to the water heating and delivery system 12 The first contamer 21 is dimensioned to loosely fit onto the second contamer 24 so that there is a gap between the two containers functioning as an air vent to release the air trapped m the second contamer when filtering the water and to admit air mto the second contamer when discharging the filtered water The first contamer 21 has a handle 30 for easy handling of the contamer and an o-πng 31 located at the upper end of the water flow passageway chamber 23 for providing a water-tight seal between the chamber 23 and water filter cartπdge 22
The automatic valve 25 compπses an openmg 43 formed on the bottom plate 38, a sealmg disc 35 for sealmg the openmg 43 when the first contamer 21 is removed from the second contamer 24, a retammg disc 33 for retammg the sealmg disc in position, a connection stem 36 for connecting the sealmg disc and retaining disc, prevention stems 44 (FIG la) formed on the inner peπpheral of the openmg 43 for preventing the retammg disc 33 from bemg pushed out of openmg 43, and a protrusion 45 formed at the bottom 28 of the second contamer 24 The sealmg disc 35, retammg disc 33 and connection stem 36 can be one integral part made of elastomer mateπal The lower end of the retammg disc 33 can be smaller than the upper end of the retammg disc 33 to facilitate the insertion of the retammg disc 33 into the openmg 43 during assembly
The automatic valve for automatically shuts off the water flow through the water flow passageway chamber 23 when the first contamer 21 is removed from the second contamer 24, I e it operates in the "Close" mode m which the sealmg disc 35 covers the openmg 43 on the bottom plate 38 due to the weight of the retammg disc 33, sealmg disc 35 and retammg stem 36 thereby blocking the water flow out of the first contamer, and automatically opens the water flow when the first contamer is mounted on the second contamer, i.e it operates m the "Open" mode m which the sealmg disc 35 is pushed away from openmg 43 by the protrusion 45 thereby allowmg the water to flow out of the first contamer through the filter cartridge 22 into the second contamer To insure that a perfect seal is formed between sealmg disc 35 and bottom plate 38, a
spring (not shown) can be placed between the prevention stems 44 and the retaining disc 33 so that the spring force pulls the sealmg disc 35 towards the openmg 43 to improve the seal between the sealmg disc 35 and the bottom 38 when the automatic valve 25 is m its "Close" mode
The water filter cartπdge 22 compπses a first cylmdπcal chamber 47 havmg a lower end 41 with numerous small openings 42 and an open upper end 48, a second cylmdπcal chamber 49 lnsertable mto the first cylmdπcal chamber havmg a lower end 51 with numerous small openings 52 and an open upper end 53, a space 59 formed between the lower end 41 of the first cyhndπcal chamber and the lower end 51 of the second cyhndπcal chamber, and filter mateπals 46 such as activated carbon contained in the space The openings 42 and 52 are small enough to retain the filter mateπals 46 m the space 59 A tapered internal shoulder 54 is formed on the upper end 48 of the first cylmdπcal chamber and a tapered external shoulder 55 is formed on the upper end 53 of the second cyhndπcal chamber Shoulders 54 and 55 are dimensioned so that the second cyhndπcal chamber 49 can be snapped mto the first chamber 47 to form a locking snap fit A enlarged portion 57 is formed near the upper end of the first cylmdπcal chamber to retain part of water fiker cartπdge 22 above the chamber 23 for easy mounting and removmg of the cartπdge Side water inlet 58 are formed on the peπpheral walls of the first and second cylmdπcal chamber near the lower end of the enlarged portion 57 to allow the water below the upper end of water filter cartπdge 22 m the first contamer 21 to enter the cartπdge The first and second cylmdπcal chambers are dimensioned so that the gap between the outer peπpheral of the second cylmdπcal chamber and the inner peπpheral of the second cylmdπcal chamber is smaller than filter mateπals to prevent the filter mateπals from leaking out of the space 59
A first important advantage of the improved water filter system is that it enables the apparatus to produce filtered water either for direct consumption or for use m makmg other dπnks such as coffee, espresso, cappuccmo and/or tea. A second important advantage of the improved water filter system is that it stores the filtered water 37 m the second contamer 24 that communicates with atmosphere through the gap between the first and second containers, therefore meeting the peπodic high flow-rate need of pump espresso machines and the apparatus disclosed in U.S Pat No 5,267,506, which need has not been met by the existing gravity water filter technology A third important advantage of the improved water filter system is that it allows one to take
only the first contamer 21 to a water faucet for refilling rather than to take the whole water filter system as required by existing dπnk water filter systems like water filter pitchers It is appreciated that the cold water filter system 11 can be constructed either as an independent apparatus for makmg filtered water or as an accessory attached to another apparatus which requires the use of water for makmg dπnks such as espresso, coffee, cappuccmo and latte
FIG 2 shows a modified embodiment of the cold water filter system 11 of FIG 1 , wherem the automatic valve 25 is located at the lower end of the water filter cartπdge 22 rather than at the lower end of the chamber 23 of the first contamer 21 The water filter cartπdge is mounted to the chamber 23 through a pair of O-πng 61 The water filter cartπdge compπses a first cyhndπcal chamber 62 havmg an upper end 63 with small openings 64 an open lower end, a second cylmdncal chamber 65 insertable mto chamber 62 havmg the automatic valve 25 formed at its lower end a porous sheet mateπal 66 sandwiched between the open lower end of the first cylmdncal chamber 62 and the open upper end of the second cylmdπcal chamber 65, filter mateπals 46 contamed m the cylmdncal space between the porous sheet mateπal 66 and the upper end 63 of the first cylmdncal chamber 62, and snap attachment details 67 formed at the open lower end of the first cylmdncal chamber 62 and the open upper end of the second cyhndπcal chamber 64 for attaching m a snappmg manner the first cylmdπcal chamber to the second cylmdncal chamber This modified cold water filter system can avoid the dπpping of water when replacing the filter cartπdge, m addition to all the advantages of the cold water filter system 1 of FIG 1
Another modified embodiment of the cold water fiker system 11 of FIG 1 is specified, which, as illustrated m FIGS 3 and 4, compπses a first containmg chamber 68 havmg a generally open upper end 69 for receiving a supply of unfikered water 70 and an outlet port 71, a second containmg chamber 72 connected to said outlet port 71 for receiving a water fiker cartπdge 22 and storing fikered water 73, and a vent conduit 74 in communication with said second containing chamber 72 through a passageway 75 for both venting the air trapped m said second containing chamber below said water fi er cartπdge during filtration and for admitting air into said second containing chamber during the discharging of the filtered water The water fiker cartπdge 22, which is identical to the water fiker cartπdge 22 of the cold water fiker system 11 of FIG 1, is removably
mounted in the upper portion of said second chamber 72 and sealed agamst said outlet port 70 of said first containing chamber through O-πng 31 The second containing chamber 72 is generally smaller than the first containing chamber 68, but it is sufficiently large to hold at least one cup of fikered water 73 The fikered water 73 can be discharged through either spigot 27 or outlet 29, both of which are located at the bottom portion of said second containing chamber 72 This modified cold water fiker system reduces the bacteπa growth m the system by maintaining the majority of the water in said first containmg chamber 68 as unfikered water, which still contains the disinfecting agent like chlorine for inhibiting bacteπa growth This modified cold water system also has all the advantages of the cold water fiker system 11 of FIG 1 except that unlike the first and second containers of the cold water fiker system of FIG 1, the first and second containing chambers are not removable from each other It is appreciated that this modified cold water fiker system can be constructed either as an independent apparatus for makmg fikered water or as an accessory connected to another apparatus which requires the use of water for makmg dπnks
Refer now to the automatic milk frothier 14 of FIG 1, the milk frothier compnses nozzle means 80 havmg a thread 81 for connecting with the steam-supplying tube 15 and an oπfice 82 for generating a steam jet, a cylmdncal chamber 83 positioned below orifice 82 havmg a steam inlet port 84 for receiving the steam jet, an mlet port 86 for the fluids such as milk to enter the chamber 83 and an outlet port 85 which is conceπtnc or lme with orifice 82 so that the steam jet can cause a vacuum m at least part of the chamber 83, hqmd passageway means 87 such as a flexible tube 93 connected to the inlet port 86 for introducing the fluid such as milk into the chamber 83, a liquid jet conduit 88 havmg a first end connected to the outlet port 85 and a second end positioned substantially downwards for transforming the hqmd such as milk which is drawn mto the chamber 83 by the vacuum m the chamber mto a hqmd jet, a contamer 89 which is positioned directly below the hqmd jet conduit to allow the hqmd jet to thrust into the hqmd m the contamer thereby producmg fine air bubbles or foam in the contamer, and a hollow cylmder 90 adapted to be moved up and down along the liquid jet conduit for controlling the amount of foam to be produced on the liquid m contamer 89 The cyhndπcal chamber 83 may conveniently be fπctionally attached and sealed to the lower part of nozzle tube 80
by means such as elastic sealing rings 91 fitted to the nozzle means 80. The hollow cylinder 90 may be slidably attached and sealed to the liquid jet conduit 88 by means such as a pair of O-rings 92.
It is prefened that the orifice 82, liquid jet conduit 88, and hollow cylinder 90 are concentric or in line with each other to increase the speed of the liquid jet into the liquid in container 89, thus increasing the quality of the foam on the liquid formed in the container. The inner diameter of the liquid jet conduit is approximately 0.7 mm to 7 mm, and preferably 1 to 3 mm for the milk frothier 14 to be attached to a pump or steam espresso machine. The length of the liquid jet conduit can be approximately 1 to 120 mm, and preferably 2 to 50 mm, depending on the diameter of the liquid jet conduit chosen. Although the liquid jet conduit used in this exemplary embodiment is of straight tubular structure, it is appreciated that the liquid jet conduit may be of a curved tubular structure. The liquid passageway means 87 is dimensioned and structured to reduce the liquid flow resistance to the cylindrical chamber 83. The orifice 82 has a diameter that is normally smaller than the diameters of the outlet 85 and liquid jet conduit 88, in order to increase the speed of the steam jet and subsequently the speed of the liquid jet. The distance between the orifice 82 of the nozzle means 80 and the outlet 85 or the liquid jet conduit 88 is small enough that the majority of the speed energy of the steam jet from nozzle means 80 is transferred to the liquid jet issuing from the liquid jet conduit 88.
It is appreciated that hollow cylinder 90 may not be needed for the production of foam by the liquid jet from liquid jet conduit 88. For the milk frothier 14 without the hollow cylinder 90, the amount of foam or foam level to be produced in the container 89 may be controlled by moving up and down either the milk frothier 14 or the container 89. It is also appreciated that there are other means, such as a support member having a cylindrical hole of predetermined diameter and length, for transforming the liquid such as milk which is drawn into said cylindrical chamber 83 into a liquid jet. It is also appreciated that a liquid jet passageway such as a chamber and tubular body may be formed at or connected to the second end of the liquid jet conduit 88 for allowmg the liquid jet to pass freely through the liquid jet passageway without touching the wall of the liquid jet passageway (not shown in FIG. 1). The liquid jet passageway is significantly larger than the liquid jet conduit 88 and helps reducing milk splashing and overflow, especially at the end of the frothing operation. It is also appreciated that the hollow cylinder 90 helps reducing the splash of milk after the milk is heated to
above certam temperature It is also appreciated that the flexible tube 93 can be immersed mto a supply of liquid such as milk contamed m a vessel other than the contamer 89, and m such arrangement the coπtamer 89 is used for receiving the hqmd jet and forming foam
To froth milk usmg the milk frothier 14 disclosed above, pour a desired amount of cold milk into contamer 89 and place the flexible tube 93 mto the hqmd in the contamer Adjust the position of the hollow cylmder 90 with the understandmg that the distance between the lower end of the hollow cylmder and the surface of milk m the contamer will be approximately equal to the thickness of the foam to be produced on the milk
Turn on the steam A steam jet is issued from oπfice 82 of the nozzle means 80 and causes a vacuum m the chamber 83 The vacuum in chamber 83 draws liquid into the chamber through the liquid passageway means 87 The steam jet then forces the qmd m the chamber 83 out of the chamber through outlet 85 and mto liquid jet conduit 88 After entering the hqmd jet conduit, the hqmd is transformed mto a thin stream and is subsequently issued at the end of the hqmd jet conduit as a hqmd jet of high speed The hqmd jet brings the surroundmg air with it as it thrusts into the milk in the contamer 89, therefore producmg foam m the contamer The surface of the foam keeps nsmg as more foam is produced m the contamer After the foam level reaches or covers the lower end of the hollow cylmder 90 as illustrated m FIG 4, the foam m the vicinity of the hq d jet rather than air is brought into the milk m the coπtamer by the hqmd jet The foam which is brought mto the milk m the contamer is regenerated, and normally at higher quality Since little additional foam is now produced, the foam level will stay at about the level of the lower end of the hollow cylmder 90 or πse very slowly In case that the surface of foam falls below the lower end of the hollow cylmder, thus makmg the surroundmg air available to the hqmd jet, additional air will be brought into the milk As a resuk, more foam will be produced until the surface of foam reaches the lower end of the hollow cylmder again
After the foam level reaches the lower end of the hollow cylmder, the mam effect of the steam is to heat up the milk After the milk is heated to a certam temperature, which is usually a httle below the boihng pomt and is the temperature just πght for makmg milk containing dπnks like cappuccmo and latte, rt is discovered that the hqmd jet in most cases disappeared and the rate at which the milk is introduced into the
chamber cylmdncal 83 is decreased It is also discovered that significantly more steam comes out of the hqmd jet conduit 88 and the milk frothier produces significantly more noise It is noticed that m some cases, especially when the lower end of the hqmd jet condurt 88 from which end the hqmd jet issues is close to the foam level m the contamer, the foam level m the contamer may start to increase quickly Any of these signs, especially the mcreases m the steam quantity, noise level and foam level, can be used as the indicators to show the operators that the milk has been heated to the nght and is ready for use m makmg cappuccmo or latte As the operator notice any of these signs, he/she should turn off the steam
If the hollow cylmder 90 is removed from the milk frothier 14, the foam level m the contamer may continue to πse until it reaches the lower end of the hqmd jet conduit 88 from which end the hquid jet issues In this case the foam level is close the lower end of the liquid jet conduit after the certam milk temperature is reached the foam level will most likely increase quickly and may cause milk overflow
It is appreciated that m some cases the milk may be heated to the certam temperature, l e the frothed milk may become ready, before the foam level in the contamer reaches the lower end of the hquid jet conduit 88 if the milk frothier does not have the hollow cylmder or the lower end of the hollow cylmder 90 if the milk frothier has the hollow cylmder In such cases, the operator can turn off the steam when the steam becomes visible around the hqmd et or the noise from the milk frothier starts to increase significantly
A unique feature of the automatic milk frothier 14 as disclosed above is that after turning on the steam, the espresso machine operators can leave the milk frothier alone and do whatever else they want to do The milk frothier will then mform the operators that the frothed milk is ready by either visible appearance of steam or audible increase m frothmg noise Besides giving the espresso machine operators great freedom, such an automatic frothmg operation makes the quantity and quality of foam on the top of the frothed milk as well as the milk temperature very consistent and essentially independent of the skill of the operators
FIGS 5 and 6 show a modified embodiment of the automatic milk frothier 14 of FIG 1, wherein the hqmd jet from the hqmd jet means 88 thrusts into the hqmd maintained in a containmg chamber 94 attached to the hqmd jet conduit 88 A circular retammg wall 95 is formed on the bottom plate 96 of said cσπtammg chamber 94 to define a space 97 directly below liquid jet conduit 88 During the operation, a certam amount
of liquid can be maintained m the space 97 of containing chamber 94 An air inlet 98 is formed at the upper portion of containing chamber 94 for air to enter the containing chamber The modified milk frothier 14A may further compnse foam level control means 99 for controlling the amount of foam to be produced on the milk m contamer 89 Foam level control means 99 compnses a fluid mlet 100 for air and foam, a flmd passageway 101 such as a flexible tube connected to air mlet 98 for providing communication between the fluid inlet 100 and the containing chamber 94, and positionmg means 102 havmg a fixture 103 attached to the penpheral wall of the containing chamber 94 and an aperture 104 into which the flexible tube 101 fπctionally fit Openings 105 are formed on the bottom plate 96 of containmg chamber 94 to discharge the hquid and foam A drammg hole 107 is formed on the bottom plate wrthm the retammg wall 95 to dram the liquid m the space 97 at the end of each frothmg operation
It is appreciated that the modified milk frothier 14A may be akered by removmg the bottom plate 96 and the parts formed on the bottom plate and by mcreasmg the length of containmg chamber 94 so that the hqmd jet from qmd jet conduit 88 is substantially encircled by the containing chamber 94 and becomes normally not visible to the operator (not shown) It is also appreciated that the modified milk frothier 14A may be akered by removmg the bottom plate 96 and the parts formed on the bottom plate, by usmg a hqmd inlet hole formed on the chamber 83 and adapted to be dipped mto the milk in contamer 89 as the hqmd passageway means to replace the flexible tube 93, and by relocating the positionmg means 102 of the foam level control means 99 so that the fluid inlet 100 can be set a certam distance above the hqmd inlet hole formed on the chamber 83 In both the alternatives for milk frothier 14 A, the containing chamber 94 is generally open at its lower end and therefore allows the hqmd jet from the hqmd jet condurt 88 to thrust directly mto the milk m coπtamer 89 thereby producmg foam m the coπtamer
To froth milk usmg the modified milk frothier 14A disclosed above, pour a desired amount of cold πulk mto contamer 89 and place the flexible conduit 93 mto the hqmd the contamer 89 Adjust the position of the fluid mlet 100 of the foam level control means 99 with the understandmg that the distance between the flmd mlet and the surface of milk will be approximately equal to the thickness of the foam to be produced on the milk
Turn on the steam A steam jet is issued from oπfice 82 of the nozzle means 80 and causes a vacuum m the chamber 83 The vacuum in chamber 83 draws liquid mto the chamber through the hquid passageway means 87 The steam jet then forces the liquid m the chamber 83 out of the chamber through outlet port 85 and mto hqmd jet conduit 88 After entering the hqmd jet conduit, the liquid is transformed into a thm stream and is subsequently issued as liquid jet at high speed from the lower end of the hqmd jet conduit 88 The hqmd jet bπngs the surroundmg air with it as it thrusts into the milk maintained in the space 97 of the containmg chamber 94, therefore producmg fine air bubbles m the containmg chamber The milk and fine air bubbles overflow the circular retammg wall 95 and exit the containing chamber 94 through openings 105 mto the coπtamer 89, in which the fine air bubbles accumulate on the milk surface and form a layer of foam The foam level continues to nse m the contamer 89 as the frothmg operation continues After the foam level reaches the flmd inlet 100 as illustrated m FIG 5, the foam, rather than air, is introduced mto the containmg chamber 94 As a resuk, httle additional foam is produced and the foam level in contamer 89 will nse very slowly or stay at around the level of the flmd mlet 100 In case that the foam level falls below the flmd inlet 100, additional air will be introduced to the liquid jet in the containing chamber 94 As a resuk, more foam will be produced until the foam reaches or covers the flmd mlet 100 again
After the foam level reaches the flmd mlet, the mam effect of the steam is to heat up the πulk After the milk is heated to a certam temperature, which is usually a little below the boihng pomt and is normally the nght temperature for makmg milk containmg drinks like cappuccmo and latte, it is discovered that the liquid jet in most cases disappeared and the rate at which the milk is introduced mto the chamber cylmdncal 83 is decreased It is also discovered that significantly more steam comes out of the containmg chamber 94 and the milk frothier produces significantly more noise Any of these signs, especially the mcreases in the steam quantity and noise level, can be used as the indicators to show the operators that the milk has been heated to the πght temperature and is ready for use m makmg cappuccmo or latte As the operator notices any of these signs, he/she should turn off the steam
Compared to the automatic πulk frothier 14, the modified milk frothier 14A reduces the πsk of milk splashing smce the liquid jet does not thrust mto the open contamer 89 directly In addition, the modified πulk
frothier 14A reduces the πsk of milk or foam overflow at the end of the frothmg operation smce the liquid jet, which contains significant amount of steam after the milk is heated above the certam temperature, thrusts into the milk m the containing chamber 94 wherein the steam is separated from the milk The overheated milk will then flow out of outlet 105 and into contamer 89, while the steam, which now has much decreased speed, will flow out of the outlet 105 and mto the surroundmg atmosphere The modified milk frothier 14 A, however, is more complex than the milk frothier 14 and is more subject to clogging and mal-function smce the foam level control means 99 may be clogged by the milk But it is appreciated that unlike the air introduction means m the milk frothmg attachments as disclosed in U S Pat Nos 4,735,133, 4,800,805, 4,945,824, 5,335,588, 4,779,519, 4,949,631, 5,265,519 and 5,330,266, the fluid passage way m the foam level control means 99 of milk frothier 14A can be made large enough to reduce the chance of clogging without impacting the performance of the milk frothier
Another modified embodiment of the automatic milk frothier 14 of FIG 1 is specified which, as illustrated m FIG 7, produces fine air bubbles or foam by drawing both air and milk mto the chamber 83 and mix g the air and milk therein The modified automatic milk frothier 14B compπses milk passageway means 107 compnsing a flexible tube 108 havmg one end connected to the inlet port 86 of chamber 83 and the other end free to move, foam level control means 109 compnsing a flmd mlet hole 110 formed on the flexible tube 108 for mtroducmg air and foam into the chamber 83 and the positionmg means 102 which is similar the positionmg means 102 for the modified milk frothier 14A of FIG 5, a porous chamber 111 havmg exit holes 112 formed on the wall of the chamber, and a discharging chamber 114 formed around the porous chamber for collecting the mixture of milk and fine air bubbles from the exit holes 112 and discharging the mixture through a mixture outlet 115 into the coπtamer 89
To froth πulk usmg the modified milk frothier I4B disclosed above, pour a desired amount of cold milk mto contamer 89 and place the flexible condurt 87 mto the hqmd m the coπtamer Adjust the position of the flmd mlet 110 of the foam level control means 109 with the understandmg that the distance between the fluid mlet 110 and the surface of milk m the contamer 89 will be approximately equal to the thickness of the foam to be produced on the milk m the contamer
Turn on the steam A steam jet is issued from orifice 82 of the nozzle means 80 and causes a vacuum m the chamber 83 The vacuum in chamber 83 draws milk from the contamer 89 and air from the fluid inlet 110 mto the chamber through the flexible tube 87 The air, milk and steam are mixed in chamber 83 and forced out of the chamber 83 by the steam jet into the porous chamber 111 The air-milk mixture then enters the discharging chamber 114 and exits through discharge outlet 115 mto contamer 89 where the fine air bubbles accumulate on top of the milk thereby producmg a layer of foam More foam is produced as the frothmg operation continues After the foam level m the contamer 89 reaches the flmd inlet 110 as illustrated m FIG 7, the foam, rather than air, is drawn mto the chamber 83 As a resuk, httle additional foam is produced and the foam level m contamer 89 will nse very slowly or stay at around the level of the flmd inlet 110 In case that the surface of foam falls below the fluid mlet 110, additional air will be brought mto the milk As a result, more foam will be produced until the foam reaches or covers the fluid mlet 100 agam
After the foam level reaches the flmd inlet 110, the mam effect of the steam is to heat up the milk After the milk is heated to a certam temperature, which is usually a little below the boiling point and is normally the nght temperature for makmg milk contammg dπnks like cappuccmo and latte, it is discovered that significantly more steam comes out of the mixture outlet 115 and the milk frothier produces significantly more noise Both the signs can be used as the indicators to show the operators that the milk has been heated to the πght temperature and is ready for use m makmg cappuccmo or latte As the operator notices any of these signs, he/she should turn off the steam
Compared to the automatic milk frothier 14, the modified milk frothier 14B reduces the πsk of milk splash and foam overflow at the end of the frothmg operation The modified πulk frothier 14B, however, is more subject to clogging and mal-function smce the fluid inlet 110 must be small, produces more noise durmg the frothmg operation, and is more complex
FIG 8 shows another modified embodiment of the automatic milk frothier 14 of FIG 1 The modified milk frothier 14C, like the modified frothier 14B, produces foam or fine air bubbles m the milk by drawing both air and milk into the chamber 83 and mixing the air and milk therein The modified automatic milk frothier 14C compnses at least one openmg 117 formed on the chamber 83 as the milk passageway into the
chamber, an air mlet 118 formed on the chamber 83, and foam level control means 99 connected to the air inlet 118 for regulating the introduction of air or foam mto the chamber The foam level control means is similar to that illustrated in FIGS 5 and 6 The openmg 117 and air mlet 118 are located sufficiently close to the onfice 82 so that the steam jet from the onfice can draw milk through openmg 117 and air through fluid inlet 100, flmd passageway 101 and air mlet 118 into the chamber To froth milk usmg the modified milk frothier 14C of FIG 8, pour an amount of cold milk into contamer 89 and insert the milk frothier mto the contamer so that the openmg 117 is immersed m the hqmd Adjust the position of the flmd mlet 100 of the foam level control means 99 with the understandmg that the distance between the flmd inlet 100 and the surface of milk in the coπtamer 89 will be approximately equal to the thickness of the foam to be produced on the milk the contamer Turn on the steam A steam jet is issued from oπfice 82 of the nozzle means 80 and causes a vacuum in the chamber 83 The vacuum m chamber 83 draws milk from the coπtamer 89 through the openmg 117 and air from the flmd inlet 100 through the flexible tube 101 mto the chamber 83 The air, milk and steam are mixed m chamber 83 and forced out of the chamber by the steam jet into contamer 89 In the contamer 89 the air bubbles from the milk-air mixture accumulates on top of the milk and forms a layer of foam The foam layer thickness mcreases as the frothmg operation continues After the foam level m the contamer 89 reaches the fluid mlet 100 as illustrated m FIG 8, the foam, rather than air, is drawn mto the chamber 83 As a resuk, httle additional foam is produced and the foam level in contamer 89 will πse very slowly or stay at around the level of the fluid mlet 100 At the same time as foam is bemg produced, the milk is bemg heated After the milk is heated to a certam temperature, which is usually a httle below the boihng pomt and is normally the πght temperature for makmg πulk contammg drinks like cappuccmo and latte, it is noticed that significantly more steam appears around the milk frothier and the foam level m the contamer 89 starts to πse quickly Both the signs, especially the rapid πse in foam level, can be used as the indicators to show the operators that the πulk has been heated to the πght temperature and is ready for use m makmg cappuccmo or latte As the operator notices any of these signs, he/she should turn off the steam
Compared to the automatic milk frothier 14, the modified milk frothier 14C is more subject to milk splash and milk overflow smce the milk frothier 14C is immersed m the milk, is more subject to clogging and
mal-function smce the foam level control means 99 must be small and can be easily clogged by the milk, is more difficuk to clean, and produces frothmg more
Refer now to the hot water fiker assembly 16 as illustrated m FIGS 1 and lb, the assembly compπses a brew head member 120 compnsing a hot water mlet 122 connected to hot water condurt 17 and a hot water outlet 123, a water filter cartndge 128 havmg a hot water mlet 129 and a fikered water outlet 130, a compartment 124 compnsing a substantially round support base 121 with openings 125, a side support wall 127 and an openmg 126 for allowmg the water fiker cartndge 128 to be inserted mto and removed out of the compartment 124, and a water distribution chamber 132 formed between the hot water outlet 123 of the brew head member 120 and the hot water mlet 129 of the water fiker cartndge 128 The compartment 124 is attached to the brew head member 120 by attachment means 133 A circular slot 134 is formed around the hot water outlet 123 on the brew head member 120 to receive a sealmg O-nng 135
The water fiker cartndge 128 is dimensioned to fit mto the compartment 124 and to form a watertight seal between the hot water inlet 129 and the O-πng 135 The water fiker cartndge compπses a first member 137 havmg a substantially cylmdπcal side wall 138, a generally flat upper end wall 140 on which the hot water mlet 129 is formed, a generally open lower end with an internal shoulder 141 with a bevel edge 148, a second member 142 havmg a substantially cylmdncal side wall 143, a generally flat lower end wall 144 on which the fikered water outlet 130 is formed, an external shoulder 145 with a bevel edge 149 formed at the lower end wall 144, a generally open upper end and a space 147 formed between the upper end wall 140 of the first member 137 and the lower end wall 144 of the second member 142 for containmg a predetermmed amount of water filtration matenals such as activated carbon 146 A handle 136 is located on the side wall 138 of the first member 137 for assisting in mounting and removmg the water fiker cartπdge 128 into and out of the compartment 124
The hot water inlet 129 on the upper end wall 140 compπses numerous holes 150 which are small enough to prevent the filter mateπal from leaking out of the cartridge 128 The holes 150 are all located a certam distance away from the side wall 138 so that a peπpheral ring area 152 where no holes are present is formed below the sealmg O-πng 135 The fikered water outlet 130 on the lower end wall 144 of the second
member 142 compnses numerous holes 151 winch are small enough to prevent the fiker mateπal from leaking out of the water fiker cartπdge 128
The internal shoulder 141 of the first member 137 and the external shoulder 145 of the second member 142 are so constructed that the second member can be snapped mto the first member The bevel edge 148 of the mtemal shoulder 141 and the bevel edge 149 of the external shoulder 145 are so formed to facilitate the snappmg action The cyhndπcal side wall 143 of the second member 142 is located a certam distance away from the bevel edge 149 and is sufficiently tall that it can cause certam tension between the internal shoulder 141 and the external shoulder 145 after the cartπdge 128 is assembled The tension between the internal and external shoulders provides a water-tight seal between the first member 137 and second member 142
It is appreciated that the hot water fiker assembly can be slightly modified by removmg the circular slot 134 and the sealmg O-nng 135 from the brew head member 120 and placing them on the penpheral πng area 152 of the upper end wall 140 of the first member 137 (not shown) It is also appreciated that the compartment 124 can be formed as an integral part of the brew head member 120 (not shown)
A modified embodiment of the hot water fiker assembly 16 of FIG l and FIG la is shown m FIG 9 Unlike the fiker assembly 16 which uses the compartment 124 to receive and retain the water fiker cartπdge 128 m place, the modified hot water fiker assembly 16A uses a bok 156 formed on the brew head member 120 and a nut 158 to receive and retam the modified water fiker cartndge 128 A in place The cartπdge 128 A has a cylmdπcal central hole 157 formed by extendmg downwards both the upper end wall 140 of the first member 137 and the lower end wall 144 of the second member 142 for receiving the bok 156 When mounting the cartπdge 128A onto the brew head member 120, one simply pushes the cartπdge upwards so that bok 156 is received m the central hole 157 and the first member 137 is received by a recession 155 formed on the brew head member 120, and then tightens the nut 158 through thread 159 onto the bok 156
The scope of the mvention is obviously not restncted to the embodiments descnbed by way of examples and depicted in the drawmgs, there bemg numerous changes, modifications, additions, and applications thereof imaginable within the purview of the claims