Coffee grinder

Abstract

A coffee grinder is described, the grinder comprising: a machine body; a grinding chamber; the first grinding disc and the second grinding disc can move relative to each other so as to grind coffee beans; and a discharge conduit for receiving ground coffee exiting the grinding chamber and for transporting ground coffee towards the container, where the discharge conduit is connected to the machine body by means of a magnetic attraction force, and where the total magnetic attraction force is greater than the weight of the discharge conduit. For example, the total magnetic attraction force is equal to the weight of the discharge conduit plus at least 50 grams, such as 50-150 grams.

Description

Technical Field

[0001] The present invention relates to a machine for grinding coffee beans. The machine for grinding coffee beans can be a stand-alone machine or can be incorporated into an at least partially automated machine for producing coffee-based beverages. Such a machine is also referred to simply as a "coffee grinder," "coffee grinder," or "grinding mill." Background Art

[0002] Two types of coffee grinders are known: those that use volumetric dosing and have a storage container, and those that are of the "on-demand" type, i.e. with instantaneous dosing but without storage of the ground coffee. The present invention relates to both types of machines, but preferably to coffee grinders of the on-demand type, with instantaneous dosing but without storage of the ground coffee.

[0003] Known coffee grinders comprise a body housing housing two superposed grinding burrs, one of which is rotationally operated by an electric motor and the other of which is axially movable relative to the first upon operation of a threaded ring engaging the interior of the burr housing body.

[0004] Once the coffee is ground, it is typically transported from the grinding chamber through a tunnel to a discharge conduit.

[0005] Typically, the discharge duct has a converging form for properly directing the ground coffee toward the container. Typically, the container is a filter that is inserted into the interior of a filter holder. As is known, the filter holder, with the filter filled with ground coffee, reversibly engages with a dispensing group of an espresso machine for preparing espresso coffee.

[0006] US 9,066,629 B1, US 2018 / 199750 A1 and US 2021 / 113020 A1 describe coffee grinders. Summary of the Invention

[0007] The applicant has noticed that coffee grounds tend to accumulate on the inner walls of the discharge duct of a coffee grinder (as well as in other areas). Clearly, the coffee grounds that accumulate on the discharge duct walls must be removed for various reasons. The first reason is that the coffee deposited on the walls deteriorates and can lead to the formation of mold and bacteria, which are then transferred to the coffee grounds used to prepare the espresso. Due to these molds and bacteria, the quality of the prepared beverage is significantly deteriorated from both a sensory and hygienic perspective.

[0008] Coffee grinder manufacturers recommend regular removal and careful cleaning of the discharge duct to avoid the aforementioned drawbacks. Unfortunately, however, some coffee grinder users neglect to maintain and clean the discharge duct, only taking action when the situation becomes noticeably worse. For example, some users may only remove the discharge duct when there are problems with the discharge of ground coffee, when the amount of ground coffee discharged is significantly less than desired, or when the user detects an unpleasant odor emanating from the coffee grinder and the ground coffee.

[0009] Another problem could be clogging of the discharge duct. Indeed, if the discharge duct is blocked in any way, the coffee, unable to drain, could return upwards towards the grinders and clog them. Coffee compressed in this way is extremely difficult to remove and may require disassembly of some components for cleaning.

[0010] The Applicant has defined the object of providing a solution to the above-mentioned problems and of providing a system for coupling a drain pipe which forces or at least encourages the user to frequently remove the drain pipe in order to prevent it from becoming blocked, even if only partially. Advantageously, the coupling system according to the invention also achieves the object of allowing maintenance and cleaning.

[0011] The Applicant has observed that the accumulation of coffee grounds on the inner wall of the discharge duct results in an insignificant increase in the weight of the discharge duct.

[0012] According to the present invention, there is provided a coffee grinder comprising a system configured to disengage the discharge duct and prevent the machine from operating when a preset weight of the discharge duct is exceeded.

[0013] In particular, a magnetic system is provided for connecting the discharge duct and the body of the coffee grinder together, and the magnetic attraction force is set to hold the discharge duct connected to the machine body up to a certain weight, which takes into account the dry weight of the discharge duct and the weight of the discharge duct with a predetermined amount of coffee grounds (considered to be acceptable and not excessive) on the inner wall. If a certain amount of coffee grounds, which is considered to be excessive, is deposited on the inner surface of the discharge duct, the magnetic attraction force will no longer be sufficient to hold the discharge duct in place and firmly connected. The separation of the discharge duct interrupts the circuit or otherwise interrupts the power supply to the machine and forces the user to disassemble the discharge duct in order to remove the grounds accumulated on the inner wall or other parts of the discharge duct.

[0014] A safety device is preferably provided to prevent the discharge pipe from falling and becoming completely separated from the rest of the machine.

[0015] According to a first aspect, the present invention provides a grinder comprising: a machine body; a grinding chamber; a first grinding disc and a second grinding disc that can move relative to each other to grind coffee beans; and a discharge duct for receiving the ground coffee leaving the grinding chamber and for conveying the ground coffee towards a container, wherein the discharge duct is connected to the machine body by means of a total magnetic attraction force, and wherein the total magnetic attraction force is greater than the mass (weight) of the discharge duct.

[0016] According to some embodiments, the total magnetic attraction force is greater than the mass (weight) of the discharge conduit by a predetermined amount corresponding to the amount of coffee grounds deposited on the components of the discharge conduit after a predetermined number of coffee bean grinding cycles.

[0017] According to some embodiments, the total magnetic attraction force is substantially equal to the mass (weight) of the discharge pipe after a predetermined number of hours or working days.

[0018] According to some embodiments, the discharge conduit comprises an engagement ring.

[0019] According to some embodiments, the engagement ring comprises two radially projecting lugs, and

[0020] Each radially projecting lug comprises a magnet, and the machine body comprises a ferromagnetic material or a ferromagnetic plate fixed to the machine body, or

[0021] Each radially projecting lug comprises a ferromagnetic material, and the machine body comprises at least one magnet at each lug.

[0022] According to some embodiments, the coffee grinder according to claim further comprises a mechanical safety device for preventing the discharge duct from falling due to excessive accumulation of coffee powder or accidental causes.

[0023] According to some embodiments, each protruding lug includes a through hole, and the machine body includes a threaded hole at each of the two lugs, wherein the mechanical safety device includes a screw that is screwed into each threaded hole so that a portion of the screw shank protrudes relative to the lug, when the discharge pipe is detached from the machine body, the portion of the shank constitutes a falling path for the discharge pipe.

[0024] According to some embodiments, the coffee grinder further comprises a micro switch for interrupting power supply to the coffee grinder when the discharge conduit is not engaged.

[0025] According to some embodiments, the discharge duct includes a chute, and the chute includes a tongue, wherein the tongue is configured to keep the microswitch depressed in a configuration in which the discharge duct is engaged with the machine body by magnetic force.

[0026] According to some embodiments, the total magnetic attraction force is equal to the weight of the discharge pipe plus at least 50 grams. In other words, the total magnetic attraction force is at least 50 grams greater than the weight of a clean (no coffee deposits) discharge pipe.

[0027] According to some embodiments, the amount by which the total magnetic attraction force exceeds the weight of a clean (coffee deposit-free) discharge conduit is between 50 grams and 200 grams, such as in the range of 50-100 grams or 50-150 grams.

[0028] According to some embodiments, the total magnetic attraction force is equal to the weight of the discharge pipe plus at least 100 grams. In other words, the total magnetic attraction force is at least 100 grams greater than the weight of a clean (coffee-free) discharge pipe. According to some embodiments, the amount by which the total magnetic attraction force exceeds the weight of a clean (coffee-free) discharge pipe is between 100 grams and 200 grams, such as in the range of 100-180 grams or 120-160 grams. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The invention will become more clearly apparent upon reading the following description, given by way of non-limiting example, with reference to the accompanying drawings, in which:

[0030] - Figure 1.1 An example of a coffee grinder according to the invention is shown;

[0031] - Figure 1.2 Shown according to Figure 1.1 A longitudinal section of the machine;

[0032] - Figure 2.1 and Figure 2.2 is a view of a coffee grinder with the discharge or output duct shown in exploded form;

[0033] - Figures 3.1 to 3.5 shows the coffee grinder according to FIG. 1 in a grinding configuration with the discharge duct in an engaged state;

[0034] - Figures 4.1 to 4.4 The coffee grinder according to FIG. 1 is shown in a configuration in which no grinding can take place, with the discharge duct being in a disengaged state. DETAILED DESCRIPTION

[0035] Figure 1.1 A coffee grinder 1 according to the invention is shown purely by way of example. Figure 1.2 yes Figure 1.1 A longitudinal section of the machine shown in FIG, showing some of the main components. Obviously, the machine according to the invention can also take completely different Figure 1.1 and Figure 1.2Since the present invention relates to only some components of the machine, other components that are not necessary for understanding the invention will not be described and / or illustrated.

[0036] The machine 1 according to the invention comprises a hopper 2 for receiving a quantity of coffee beans to be ground, a grinding chamber 3 with grinding burrs 4, 5 for grinding the coffee beans received from the grinding chamber, and a discharge duct 20 for conveying the ground coffee towards a collecting container. Figure 1.2 Also shown is a motor 6 with a drive belt for rotating one of the two grinding discs 4, 5 relative to the other.

[0037] Typically, the collecting container is a filter 30 of a filter holder 32 for an espresso machine. The coffee grinder 1 may comprise means 9 for modifying the mutual distance between the grinding discs 4, 5 and thereby adjusting the fineness of the coffee powder leaving the grinding chamber.

[0038] Advantageously, the coffee grinder 1 may comprise a machine body 8 housing the various components. The machine body 8 may be made at least partially of metal.

[0039] The coffee grinder 1 may comprise a support 10 for supporting the filter holder 32 in a correct position such that the ground coffee is directed towards the filter 30 supported by the filter holder 32 .

[0040] The discharge duct 20 preferably has a converging form for conveying the ground coffee from a larger cross-section corresponding substantially to the cross-section of the grinding chamber to a smaller cross-section compatible with the diameter of the filter 30 .

[0041] like Figure 2.1 and Figure 2.2 As shown in FIG, the discharge duct 20 according to the invention comprises an inner cone 22 for suitably conveying the ground coffee leaving the grinding chamber, a chute 23 and an engagement ring 24 for removably securing the chute 23 to the body 8.

[0042] The inner cone 22 is generally funnel-shaped. According to some embodiments, the inner cone 22 has a protruding edge 221 at the larger diameter opening.

[0043] The inner cone 22 may be made of metal, but is preferably made of a thermoplastic material.

[0044] The chute 123 has the function of receiving the ground coffee from the inner cone 22 and guiding it towards the receiving container 30. Advantageously, part of its surface can be open. In other words, it is not a closed tube (or cone). It can be made of metal or any thermoplastic material.

[0045] The chute 23 is integrally or detachably connected to the coupling ring 24. Internally, the coupling ring 24 is shaped substantially complementary to the edge 221 of the inner cone 22. In other words, when the coupling ring 24 is connected to the machine body 8, it supports the inner cone 22 and the chute 23.

[0046] The coupling ring 24 is detachably connected to the machine body 8. According to the present invention, the coupling ring 24 is connected by means of magnetic force. For example, the coupling ring 24 includes at least one magnet 28 and at least one ferromagnetic material 82 at the location on the body 8 of the coffee grinder 1 where the coupling ring 24 is connected, for example Figure 3.4 In other embodiments, the engaging ring 24 includes at least one ferromagnetic material (or is essentially formed of a ferromagnetic material) and includes one or more magnets, such as magnetic plates, at the location on the body 8 of the coffee grinder 1 where the engaging ring 24 is connected.

[0047] Alternatives to the solutions described above are obviously possible. For example, the coupling system, which is currently magnetic, could also be obtained by means of fixing elements of the mechanical type, ie lateral springs or snap-fit ​​pushers.

[0048] The magnet 28 may be a single magnet, or a plurality of magnets 28 .

[0049] According to some embodiments, the magnets 28 are in the form of small cylinders and are preferably arranged at equal angular intervals.

[0050] In one embodiment, the engagement ring 24 includes one or more radially outwardly projecting lugs 25. For example, two radially projecting lugs 25 may be provided. Each protruding lug 25 includes a magnet 28 configured to generate a magnetic attraction force with the ferromagnetic plate 82 or any corresponding ferromagnetic portion of the body 8 of the machine 1.

[0051] According to the invention, the total magnetic attraction force between the coupling ring 24 and the machine body 8 is the sum of the magnetic forces of the individual magnets.

[0052] Typically, during use of the coffee grinder, coffee grounds are deposited inside the discharge duct 20, for example, on the walls of the inner cone 22 and / or on the surface of the chute 23. If the discharge duct 20 is not cleaned regularly, the coffee grounds form a layer, and the weight of the coffee grounds deposited inside the discharge duct may be as high as 100-120 grams or more. Obviously, the amount of coffee grounds that can be deposited inside the discharge duct varies greatly and depends on, for example, the type of coffee compression and particle size, as well as environmental conditions (particularly humidity).

[0053] According to the invention, the total magnetic attraction force is calculated to be greater than the weight of the discharge duct alone. In particular, the total magnetic attraction force is substantially equal to the sum of the weight of the discharge duct and the weight of the allowed amount of deposited ground coffee powder, i.e.

[0054] TMF=MDC+MWP+THR

[0055] in:

[0056] TMF is the total magnetic force, defined by the sum of the magnetic forces of the individual magnets;

[0057] MDC is the weight of a clean discharge pipe, free of deposited coffee grounds; and

[0058] The MWP is the permissible weight of coffee grounds lost due to deposition on the wall (and / or other parts) of the discharge duct 20. The permissible weight of coffee grounds corresponds to the maximum amount of coffee grounds, if exceeded, the discharge duct 20 should be cleaned and the coffee grounds removed.

[0059] THR is a term used to describe the thrust exerted by the ground coffee exiting the grinding chamber. As the ground coffee accumulates, it eventually comes into contact with moving parts and is pushed by them. Furthermore, in the event of a blockage, the exiting particles encounter stationary particles and are stopped, starting to increase in density and pushing in all directions. While this force cannot be precisely quantified, it represents a significant portion of the force required to cause the discharge pipe to detach. This component increases with the amount of accumulated coffee. With small amounts of accumulated coffee, it is insignificant.

[0060] The permissible weight of coffee powder can be determined by the manufacturer based on experience and the specific form of the discharge duct. In fact, the form of the discharge duct affects the amount of coffee powder that does not reach the filter but remains on the discharge duct wall or in any corner thereof.

[0061] For example, a coffee grinder manufacturer may detect that, during normal daily use (taking into account the number of doses ground at atmospheric pressure and a reference ambient temperature, under predetermined conditions of air humidity), the amount of coffee grounds that tends to be deposited on the discharge duct ranges between x and y grams. Under the same environmental and operating conditions, the amount of coffee grounds deposited on the discharge duct over two days can be estimated to be twice the daily amount. As the number of days increases, the component caused by the thrust becomes more significant.

[0062] If a manufacturer wishes to encourage baristas to remove accumulated coffee to prevent blockages and keep the discharge duct clean on a daily basis, the total magnetic force TMF would be determined to be equal to the weight of the discharge duct MDC plus weight x, or more cautiously, weight y, multiplied by a safety factor if necessary. In this way, baristas can more easily complete a typical workday.

[0063] Similarly, if a manufacturer wants to encourage baristas to clean the discharge pipe weekly, the total magnetic force TMF can be determined to be equal to the discharge pipe's weight MDC plus weight x, or more cautiously, weight y, multiplied by the number of workdays, such as 5, 6, or 7. Advantageously, a safety factor can be envisioned. This way, baristas can more easily define a typical work week. For example, the safety factor could be a 10% increase in the permissible weight MWP.

[0064] Alternatively, the manufacturer may aim to prevent clogging and therefore also calibrate the total magnetic force with a discharge duct on which there is an accumulation of coffee grounds in an amount between about 50g and 200g, or between about 100g and 160g, or between about 110g and about 150g, or between about 120g and 140g, or in any other sub-range.

[0065] By setting the total magnetic force in this way, if the barista does not perform cleaning of the discharge duct after a given period of time, the total magnetic force is no longer able to hold the discharge duct 20 to the machine body 8. In other words, if the weight of the ground coffee deposited in the discharge duct exceeds the permissible weight, the weight of the contaminated discharge duct is too great and the magnets are no longer able to perform their function of keeping the duct stably fixed to the machine body 8.

[0066] For example, if the total magnetic force TMF is equal to MDC+y grams because the manufacturer recommends daily cleaning, further use of the machine without cleaning the discharge duct at the end of the day may (presumably within a short time) cause the discharge duct 20 to become detached, making it impossible to use the machine with a contaminated discharge duct.

[0067] For example, x can be about 2 g, 3 g, or 4 g. For example, y can be about 4 g, 5 g, or 6 g.

[0068] Generally speaking, a blockage can occur suddenly, due to poor machine handling or incorrect use by the user, for example when the user hits the outlet of the discharge cone with the filter holder in an incorrect manner. Alternatively, during normal use, it can occur after several hundred kilograms of coffee (e.g., 300-500 kilograms) have been ground, depending on how much coffee tends to settle on the surface. This is equivalent to at least one or two months of operation in an extremely busy small shop.

[0069] According to some embodiments, the total magnetic force is greater than about 5% of the weight of the discharge conduit.

[0070] According to some embodiments, the total magnetic force is greater than about 10% of the weight of the discharge conduit.

[0071] According to some embodiments, the total magnetic force is greater than about 15% of the weight of the discharge conduit.

[0072] According to some embodiments, the total magnetic force is between about 10% and 30% of the weight of the discharge conduit.

[0073] According to one embodiment of the present invention, a first safety device is provided to prevent the discharge pipe 20 from falling due to an accident or when the weight of the contaminated discharge pipe exceeds the total magnetic force. The first safety device is mechanical and defines a landing point for the detached discharge pipe. The landing point can also be a small distance from the point where the discharge pipe is engaged.

[0074] According to one embodiment, a through hole 26 for a screw 27 is provided in each lug 25 that protrudes radially from the coupling ring 24. A threaded hole 81 for the screw 27 is provided on the machine body 8 to which the coupling ring 24 is connected (for each through hole 26 in the lug). The shank of each screw 27 has a length that is greater than the sum of the thickness of the lug 25 and the depth of the threaded hole. In this manner, even when the screw 27 is fully threaded into the hole, the head 271 of the screw 27 remains spaced apart from the lug 25. If the discharge pipe 20 becomes disengaged, it can only fall through the distance 272 corresponding to the section of the screw 27 shank that protrudes downward relative to the lug 25 when the discharge pipe 20 is connected to the machine body 8.

[0075] Figure 3.1 、 Figure 3.2 、 Figure 3.3 and Figure 3.4 The section of the safety screw 27 and handle 272 is shown, which corresponds to the maximum drop distance if the discharge conduit 20 becomes disengaged. Figure 4.1 、 Figure 4.2 and Figure 4.3 The detached discharge pipe 20 is shown, and it is clear how it "lands" on the head 271 of the screw 27 and rests thereon. The discharge pipe 20 has fallen through the Figure 3.1 、 Figure 3.2 、 Figure 3.3 and Figure 3.4 The distance limited by the section of the screw visible in FIG. 2 (again indicated by 272). The drop path may be a millimeter or in any case a few millimeters, advantageously less than 10 mm, for example about 5 mm.

[0076] According to an embodiment of the invention, the coffee grinder further comprises a micro switch 40 for interrupting the power supply to the motor causing the rotation of (at least) one grinding disc when the discharge duct is in the disengaged configuration. Figure 3.5 The micro switch 40 is shown in a closed circuit configuration, wherein the motor 6 receives power and can rotate at least one of the grinding discs 3 and 4. Figure 4.4 , the microswitch 40 is shown in an open configuration, which corresponds to a configuration in which the discharge conduit 20 is no longer supported by magnetic forces.

[0077] According to one embodiment, a conductive tongue 41 may be provided for closing the microswitch 40, which conductive tongue 41 is connected to the chute 23 of the discharge duct 20. Alternatively, a metal contact switch of the reed sensor type may be used.

Claims

1. A coffee grinder (1), comprising: A machine body (8); a grinding chamber (3); a first grinding disc (4) and a second grinding disc (5), the first grinding disc and the second grinding disc being movable relative to each other for grinding coffee beans; and a discharge duct (20) for receiving ground coffee leaving the grinding chamber (3) and conveying the ground coffee towards a container (30), wherein the discharge duct (20) is connected to the machine body (8) by means of a total magnetic attraction force, and wherein the total magnetic attraction force is greater than the weight of the discharge duct (20).

2. The coffee grinder (1) according to claim 1, wherein The total magnetic attraction force is greater than the weight of the discharge duct (20) by a predetermined amount corresponding to the amount of coffee grounds deposited on the components of the discharge duct (20) after a predetermined number of coffee bean grinding cycles.

3. The coffee grinder (1) according to claim 1, wherein The total magnetic attraction force is substantially equal to the weight of the discharge pipe (20) after a predetermined number of operating hours or days.

4. Coffee grinder (1) according to any one of the preceding claims, wherein The discharge conduit (20) includes an adapter ring (24).

5. The coffee grinder (1) according to claim 4, wherein The engaging ring (24) comprises two radially projecting lugs (25), and wherein Each radially projecting lug (25) comprises a magnet (28), and the machine body (8) comprises a ferromagnetic material or a ferromagnetic plate (82) fixed to the machine body (8), or Each radially projecting lug (25) comprises a ferromagnetic material, and the machine body (8) comprises at least one magnet at each lug (25).

6. The coffee grinder (1) according to claim 4 or 5, further comprising a mechanical safety device (27, 28, 29, 81) for preventing the discharge duct (24) from falling due to excessive accumulation of coffee powder or accidental reasons.

7. The coffee grinder (1) according to claim 6, wherein Each lug (25) comprises a through hole (26), and the machine body (8) comprises a threaded hole (81) at each of the two lugs (25), wherein the mechanical safety device comprises a screw (27) threaded into each threaded hole (81) so that a portion (272) of the shank of the screw (27) protrudes relative to the lug (25), and when the discharge pipe is detached from the machine body (8), the portion (272) of the shank constitutes a falling path for the discharge pipe (20).

8. The coffee grinder (1) according to any one of the preceding claims, further comprising a micro switch (40) for interrupting the power supply to the coffee grinder (1) when the discharge duct (20) is not engaged.

9. The coffee grinder (1) according to claim 8, wherein The discharge duct (20) includes a chute (23), and the chute (23) includes a tongue (41), wherein the tongue (41) is configured to keep the micro switch (40) pressed in a configuration in which the discharge duct (20) is engaged with the machine body (8) by means of the total magnetic force.

10. Coffee grinder (1) according to any one of the preceding claims, wherein The total magnetic attraction force is equal to the weight of the discharge pipe (20) plus at least 50 grams.

11. Coffee grinder (1) according to any one of the preceding claims, wherein The total magnetic attraction force is equal to the weight of the discharge pipe (20) plus at least 50-200 grams or 50-150 grams.

12. The coffee grinder according to claim 10 or 11, wherein The total magnetic attraction force is equal to the weight of the discharge pipe (20) plus at least 100 grams.

13. Coffee grinder (1) according to any one of the preceding claims, wherein The total magnetic attraction force is equal to the weight of the discharge pipe (20) plus 100-200 grams, such as 100-180 grams or 120-160 grams.

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