Tamping bar for compressing coffee grounds in filter basket

Abstract

The utility model relates to a tamper for compressing coffee grounds in a filter basket. A filter basket for a beverage machine includes a side wall and a screen portion. The filter basket forms a brewing chamber into which ground coffee or other products are added. The infusion chamber is defined by a tapered sidewall, a screen surface, and a smooth profile between the tapered sidewall and the screen surface. The tamper is configured with a corresponding tapered side wall that allows the tamper to fit within the infusion chamber to apply pressure to the ground coffee contained in the infusion chamber. The tapered tamper is configured to mimic the shape of the infusion chamber to allow close contact and better match between the tamper head side wall and the infusion chamber side wall to produce a more uniform compact.

Description

[0001] Background

[0002] The field of the present disclosure relates to the extraction of compounds from plant materials such as coffee beans, pods, tea leaves, and any type of powdered or ground comminuted compound. More specifically, the field of the present disclosure relates to a reusable filter basket for use with extraction equipment.

[0003] Existing methods and equipment for extracting compounds can result in suboptimal extraction conditions due to uneven material distribution, uneven pressure, and uneven liquid flow characteristics within the extraction chamber, which lead to inconsistent extracts, material waste, and suboptimal flavor of the extracted compounds.

[0004] While compounds can be extracted from plant materials according to existing equipment and methods, it is desirable to provide improvements in achieving more consistent extractions and other features that will become apparent from the following description.

[0005] Overview

[0006] According to some embodiments, a beverage machine filter basket includes a circumferential rim; a tapered or constant diameter sidewall that hangs down from the rim; a funnel region that hangs down from the tapered sidewall, the funnel region having a first diameter adjacent to the tapered sidewall and a second diameter spaced apart from the first diameter, the second diameter being less than the first diameter; a curved transition between the tapered sidewall and the funnel region; and a filter screen having a plurality of perforations formed therethrough. A tamper having a tapered sidewall can be used to compact coffee within the tapered filter basket. The tapered tamper will cooperate more closely with the filter basket having a tapered sidewall to produce a more compacted coffee prior to extraction.

[0007] In some embodiments, the filter basket has a central axis, and the tapered sidewall forms an angle with respect to the central axis. In some embodiments, the angle can be less than 20 degrees, or less than about 15 degrees, or less than about 10 degrees. The tamper can have the same angle of the tapered sidewall to nest within the filter basket. In some cases, the curved transition between the tapered sidewall and the funnel region has a radius of curvature greater than 0.25 mm and less than 20 mm. In certain cases, the radius of curvature is between approximately 0.25 mm and 4 mm, or can be between 3 mm and 4 mm. In certain cases, the radius of curvature is approximately 1 mm, 1.5 mm, 2 mm, 3 mm, or 4 mm.

[0008] In some embodiments, the filter screen defines a curved surface that can be concave when viewed from the inside of the filter basket. The curved surface can have a radius of curvature greater than the total height of the filter basket. In some cases, a plurality of apertures are arranged within a bounded area that is less than 90% of the surface area of the filter screen. For example, in the case where the filter screen surface forms a circle when viewed from the top, the arrangement of the apertures is adapted to be within an area that is less than 90% of the total surface area of the filter screen. In other words, the apertures are not formed over the entire surface area of the filter screen but are restricted to an area that is less than the entire surface area of the filter screen. In some cases, a plurality of apertures are arranged within a bounded area that is less than the entire area of the filter screen, such as less than 80%, or 70%, or 60%, or 50% of the surface area of the filter screen.

[0009] In some embodiments, the conical sidewall, the funnel region, and the filter screen together form a brewing chamber. In use, a material (e.g., ground coffee beans) can be placed into the brewing chamber. In some examples, the brewing chamber has a diameter that continuously decreases from the top of the filter basket adjacent the rim to the bottom of the filter screen. A tamper can be used to compress or compact the material within the brewing chamber. The tamper can have a conical sidewall to coincide with the sidewall of the filter basket.

[0010] According to some embodiments, a beverage machine filter basket includes a circumferential rim, a conical sidewall hanging down from the circumferential rim, and a filter screen hanging down from the conical sidewall, the filter screen forming a curved surface. The tamper can have a conical sidewall that is configured to fit within the filter basket.

[0011] In some cases, the conical sidewalls of the filter basket and / or the tamper continuously taper from a first diameter to a second diameter, the second diameter being less than the first diameter. A plurality of apertures can be formed within the curved surface of the filter screen. In some cases, the plurality of apertures are arranged in a pattern that has a radius less than 90% of the radius of the filter screen.

[0012] In some embodiments, the conical sidewall and the filter screen form a brewing chamber, and the brewing chamber can continuously narrow from a first diameter adjacent the rim to a point at the center of the filter screen. The tamper can have a corresponding conical sidewall such that the tamper can fit within the brewing chamber. The tamper can further include a handle protruding from the upper surface of the tamper, the handle being configured to allow a barista to grasp the handle and apply a compaction pressure to the coffee beans within the brewing chamber through the tamper.

[0013] The embodiments described herein provide a number of advantages over existing filter designs used in coffee extraction. For example, a significant drawback of current systems is frequent channeling, where high-pressure fluid flow finds or creates the path of least resistance through the coffee puck, resulting in a large amount of pressurized water having little (or no) contact with the ground coffee. The result is uneven extraction, inefficient extraction, and an undesirable beverage. The embodiments described herein reduce some of the internal bends and reverse fluid pressure waves that have a tendency to disrupt the coffee puck and create channeling. The embodiments described herein further smooth the fluid pressure waves and improve the consistency and uniformity of the extracted beverage. Brief Description of the Drawings

[0015] A better understanding of the features, advantages, and principles of the present disclosure will be obtained by reference to the following detailed description of illustrative embodiments and their accompanying drawings, in which:

[0016] Figure 1A and Figure 1B shows a handle for a tamper according to some embodiments;

[0017] Figure 2A and Figure 2B shows a tamper head from a side view according to some embodiments;

[0018] Figure 3 illustrates a perspective view of a tamper showing the tamper handle and the tamper head according to some embodiments;

[0019] Figure 4 illustrates a perspective view of a tamper showing the tamper handle and the tamper head according to some embodiments; and

[0020] Figure 5 illustrates a tamper head according to some embodiments.

[0021] Detailed Description

[0022] The following detailed description provides a better understanding of the features and advantages of the utility model described in the present disclosure according to the embodiments disclosed herein. Although the detailed description includes many specific embodiments, these are provided only as examples and should not be construed as limiting the scope of the utility model disclosed herein.

[0023] According to some embodiments, the systems and methods described herein can be used to extract compounds from plant materials and, in some cases, to extract compounds from coffee beans using water as a solvent.

[0024] Coffee beans are typically roasted to reduce complex sugars and caramelize some of the simple sugars within the coffee beans. In some cases, roasting the coffee beans also breaks down acids in the coffee beans. In some cases, coffee beans are roasted to balance the acidity and sweetness of the beans so that a pleasant aroma and flavor are produced as soon as compounds are extracted from the coffee beans with hot water.

[0025] In some cases, the coffee beans are ground and used in an extraction process to produce espresso, or any one of a number of other coffee or espresso-based beverages, to name a few, such as cappuccino, macchiato, latte, cortado, americano, mocha, and other coffee beverages.

[0026] In a typical espresso-making process, the coffee beans are ground and exposed to near-boiling water (e.g., about 200°F or about 93°C) at a pressure of about 130 psi (9 bar). As the water passes through the ground coffee beans under pressure, the water dissolves some of the compounds in the coffee beans and a dark, rich, hot coffee-based beverage is achieved.

[0027] An espresso machine brews coffee by forcing pressurized water through a "puck" of ground coffee and a filter. The coffee puck is formed by adding a desired amount of ground coffee to a portafilter and tamping the ground coffee to achieve distribution and density within the portafilter. The portafilter is a device with a handle and a filter basket within the handle. The filter basket holds the coffee puck, and the handle is used to attach the portafilter to the espresso machine, thereby forming a brewing chamber within the filter basket.

[0028] The espresso machine heats the water and forces the hot water through the coffee puck and the filter basket and out of the portafilter into a beverage cup. In some embodiments, the filter basket includes a plurality of filter holes through which the pressurized hot water exits the filter basket and is then directed to the beverage cup. The process of extracting an espresso-based beverage in this manner can be referred to as "pulling a shot".

[0029] Multiple factors act together to affect the quality of the extracted beverage. For example, the particle size of the ground coffee beans, the quality of the coffee beans, the roasting of the coffee beans, the heat of the water, the time the water is in contact with the ground coffee, the distribution of the ground coffee within the filter basket, and the compression density of the ground coffee beans within the filter basket, etc. It is worth noting that several of these variables are at least partially affected by the filter basket itself.

[0030] For example, the filter basket is shaped to form a chamber into which ground coffee beans are added and tamped to provide a coffee puck. In addition, the filter basket has a plurality of holes that allow the extraction compounds dissolved in the water to leave the filter basket. The shape of the filter basket controls the pressure distribution of the pressurized water forced through the puck. The holes in the filter basket somewhat control the flow rate of water out of the filter basket, thereby determining the time that the water contacts the ground coffee. Thus, the configuration of the filter basket can play an important role in the quality of the espresso. In addition, the configuration of the tamper may affect the formation of the coffee puck. In some cases, the tamper is shaped to coordinate with the shape of the filter basket.

[0031] The time that the water contacts the puck has an important impact on the taste of the espresso. Typically, the first compounds extracted from the ground coffee are acids and fats, which contribute to the salty - sour taste in the espresso. When the water remains in contact with the ground coffee long enough to continue extraction, next the sugars are extracted, which provide sweetness to the extracted espresso. Finally, if the extraction process is allowed to continue, the plant fibers are broken down and extracted, which provides a dry, bitter taste to the espresso.

[0032] By varying the time that the heated water contacts the ground coffee beans, the taste of the espresso changes along a continuum from sour to sweet to bitter. In most espresso machines, the extraction time is directly related to the pressure of the heated water and the configuration of the filter basket, and more specifically, to the shape of the filter basket, the arrangement and configuration of the holes in the filter basket, and the density of the coffee puck. The particle size of the ground coffee also plays a role in the extraction time, and this is another variable that can be adjusted according to personal preference to change the taste of the espresso.

[0033] An espresso can be defined by the quality of the extraction and the strength of the beverage. In some cases, the strength is related to the amount of compounds dissolved in the beverage. For example, an espresso may contain approximately 7% to 12% dissolved solids and approximately 88% - 93% water. Personal preference can vary the desired dissolved solids, but this range is typical for many espresso - based beverages. The strength of the beverage is also related to the extraction. For example, the volume of water and the extraction time determine the strength of the beverage.

[0034] While each individual consumer can experiment with the above variables to determine their own preferred espresso, there are some characteristics that can be widely applicable to many coffee drinkers. For example, when pulling an espresso shot, an undesirable situation is jetting, where the pressurized water finds the path of least resistance through the coffee puck, and a large amount of water exits the filter basket with very little solids, and jetting from the filter basket is typically visible, indicating that the pressurized water stream has not experienced sufficient time for extraction. This phenomenon can be caused by uneven tamping, uneven grind distribution, or channeling effects where the pressurized water finds or creates a channel through the puck.

[0035] In some embodiments, the filter basket can affect the quality of extraction by changing the flow characteristics of the extraction water. Several advantages will become apparent from the following description of an improved filter basket with a unique and novel barrel shape and configuration. As used herein, the term "pozzetto" refers to the internal shape of the bottom of the filter basket, where the strainer is a recess and can be formed as a recess compared to the internal level of the tamping area. In some embodiments, the pozzetto can be a tall (alto) or relatively shallow strainer, or can be described as low (basso), which refers to a relatively deep strainer. The size and shape of the tamper can similarly conform to the internal shape and dimensions of the pozzetto. In some cases, the filter basket and the tamper cooperate to provide a positive stop that determines the maximum distance the tamper can extend into the filter basket. For example, the filter basket can define a shoulder with a reduced diameter that interacts with the lower surface of the tamper to inhibit further extension of the tamper into the filter basket. The positive stop can help provide a repeatable compression of the coffee grounds within the filter basket.

[0036] Referring Figure 1A and Figure 1B , the handle 102 for the tamper can be formed to have a circular cross-section and define different diameters along the length of the handle. For example, the handle can include a first end 104 and a second end 106. The first end 104 and the second end 106 can have different diameters, and the length between the first end and the second end can have a profile where the handle 102 can be wider or narrower at different regions along its length. The handle can be formed for comfort, for example, by shaping the handle to fit comfortably within the user's hand. The handle can be formed from any suitable material (such as wood, metal, alloy, plastic material, composite material, or any combination of materials). Figure 1A is Figure 1B a cross-sectional view taken along section line 1A-1A of

[0037] Figure 2A and Figure 2B Figure 2B illustrates the head 110 of a tamper according to some embodiments. The head 110 can generally be puck shaped, i.e., having a diameter D1 greater than the thickness t of the head 110. Dimensions such as the diameter D1, thickness t, radius, etc. can be any suitable dimensions that result in a tamper head that fits within the filter basket and can compress the coffee grounds in the filter basket to produce a puck.

[0038] The head 110 can have an upper surface 112, a bottom surface 114, and a thickness t between the upper surface 112 and the bottom surface 114. The thickness t can be defined by a sidewall 116. In some cases, the sidewall 116 is not perpendicular to the bottom surface 114. In other words, the plane defined by the bottom surface 114 and the sidewall form an angle other than 90° between the plane defined by the bottom surface 114 and the sidewall. In other words, the head 110 can have an axis A extending from the upper surface 112 to the bottom surface 114, and the surface of the sidewall is not parallel to this axis.

[0039] Similarly, in some embodiments, the filter basket has an axis, and one or more sidewalls are not parallel to this axis. In some cases, each of the sidewalls of the filter basket is not parallel to this axis. In other words, when viewed from the side, none of the surfaces forming the brewing chamber are vertical, but form an angle greater than zero with respect to the axis. In certain cases, the tamper sidewall is parallel to the filter basket sidewall. The sidewall 116 can be formed with one or more annular grooves 120. The grooves can assist in inserting and removing the tamper head 110 into and from the filter basket.

[0040] In some embodiments, the bottom surface 114 defines a shape other than a plane. For example, the bottom surface 114 need not be flat, but can be convex, concave, stepped, textured, or form some other shape. In some cases, the bottom surface can be formed with an image, text, graphic, or logo that causes an imprint to be pressed or recessed into the coffee puck. For example, a company logo can be formed as a protrusion or recess in the bottom surface 114, and when the tamper head compresses the coffee puck, the company logo remains prominent or recessed in the compressed coffee puck.

[0041] In some examples, the sidewall of the tamper mimics the tapered sidewall of the filter basket. As Figure 2A shown, the outer angle α between the bottom surface 114 and the sidewall 116 can be less than 270°, such as 269°, or 268°, or 267°, or 266°, or 265° or some other suitable angle.

[0042] In some embodiments, the ram head 110 may have a threaded hole 118, which may be a stop hole. The threaded hole 118 may be configured to receive a threaded fastener, such as a bolt. In some cases, the shank 102 has a threaded protrusion protruding from the bottom of the shank, and the threaded protrusion may be received by the threaded hole 118 of the ram head 110 to allow the ram head 110 to be threadedly connected to the shank. In other cases, a threaded fastener may be attached to the ram head 110, and then, as needed, the threaded fastener may be screwed into the shank 102 to attach the ram head 110 to the shank 102. In some examples, the shank 102 is permanently attached to the ram head 110, and in some cases the shank 102 and the ram head 110 may be integrally formed.

[0043] Figure 3 and Figure 4 An example of the ram 100 is illustrated, in which the shank 102 is fixed to the ram head 110. The ram 100 may be formed of any suitable material or combination of materials. In some cases, the ram head 110 may be formed of stainless steel. The shank may be formed of wood, a plastic material, a metal (such as stainless steel), or a combination of materials.

[0044] As Figure 3 shown, the ram head has a diameter D1 near its upper surface 112 and a diameter D2 near its bottom surface 114. In certain cases, the diameter D1 is equal to or approximately equal to the diameter D2. In these embodiments, the ram head 110 may have a vertical sidewall 116. Additionally, in some cases, the sidewall 116 may be smooth, having minimal grooves or protrusions or no grooves or protrusions, as shown.

[0045] As Figure 4 shown, in some embodiments, the upper surface 112 may have a first diameter D1, while the bottom surface 114 may have a second diameter D2, where D2 < D1. In other words, the sidewall 116 is not parallel to the central axis extending through the shank 102 and the ram head 110. Additionally, the sidewall 116 may have a groove formed therein, which may be formed to reduce the surface area in contact with the filter basket.

[0046] Referring Figure 5, the side wall 116 of the tamper head 110 can be uniformly tapered from a first diameter D1 to a second diameter D2 that is less than the first diameter. That is, the side wall 116 can have a first diameter adjacent to the upper surface 112 that is greater than the diameter of the side wall 116 adjacent to the bottom surface 114. The side wall 116 can have a uniform taper, or can have one or more annular grooves 502 around the perimeter of the tamper head. The junction of the side wall 116 and the bottom surface 114 can have a radius 117, and in some cases, the radius 117 is between approximately 0.0025 inches (0.06 mm) and 0.25 inches (6.35 mm).

[0047] In some cases, the tamper head 110 defines a tapered side wall that can be configured to fit within a correspondingly shaped tapered filter basket. The bottom surface 114 can have a radius R1 of curvature 508 such that the bottom surface is not planar. In some cases, the bottom surface 114 can be hemispherical. The radius of the curvature 508 can be approximately 5 inches (127 mm), 10 inches (254 mm) or greater.

[0048] In some embodiments, the tamper head 110 has a first width near its top surface that is greater than the width near the bottom surface. For clarity, the bottom surface is the surface configured to contact the coffee grind for tamping, and the top surface is opposite the bottom surface. In some cases, the side wall between the top surface and the bottom surface is uniformly tapered, while in other cases, the side wall can be curved as it extends from the top surface to the bottom surface. In certain cases, the tamper can have a shape other than circular. For example, the tamper head can have any suitable shape, such as square, rectangular, oval, or any regular polygon shape, such as pentagon, hexagon, heptagon, octagon, or other shapes.

[0049] In some cases, the side wall can be stepped, such as having multiple sections with a constant diameter (or a constant width in the case of a non-circular tamper head), where more than one section has a different diameter.

[0050] In some examples, as described herein, the tamper head can be attached to a handle or can be coupled to a machine. In some cases, the machine can apply a tamping force automatically or manually, and the tamper head can be coupled to the machine to allow the machine to manipulate the tamper head. For example, the machine can include an actuator that moves the tamper head to compress coffee grounds. Alternatively or additionally, the machine can be coupled to the tamper head and can actuate a manual lever to manipulate the tamper head to compress coffee grounds, which can be referred to as a mechanical and / or manually-driven tamping device. In some cases, the tamper head can be coupled to a lever mechanism that can be manually or automatically manipulated to compress coffee grounds with the tamper head. In some embodiments, the tamper head and / or the tamper can be coupled to an electrically-driven mechanical tamping machine that uses electricity and one or more drive elements to drive the tamper to compress coffee grounds.

[0051] The transition from the sidewall 116 to the bottom surface 114 can include a fillet radius 117 that ranges, for example, from about 0.0025 inches (0.06 mm) to 0.25 inches (6.35 mm). The fillet can be convex or concave. In some examples, the transition from the sidewall to the bottom surface forms a sharp corner with a very small or no fillet radius. The tamper head can have any suitable diameter or combination of diameters, which can be approximately about 42 mm, 48 mm, 51 mm, 55 mm, 58 mm, 60 mm or any other suitable size, such as less than 42 mm or greater than 60 mm, or a diameter between about 30 mm and 80 mm. The upper surface 112 can have one diameter, while the bottom surface 114 can have a second diameter different from the first diameter.

[0052] The upper surface 112 of the tamper head can be any suitable shape, such as generally flat, tapered, curved, angled, or have any other suitable surface shape to allow the tamper head 110 to be coupled to a handle, mechanism, or machine.

[0053] One of ordinary skill in the art will recognize that any process or method disclosed herein can be modified in a variety of ways. The process parameters and order of the steps described and / or illustrated herein are given only as examples and can be varied as needed. For example, although the steps described and / or illustrated herein can be shown or discussed in a particular order, these steps do not necessarily need to be performed in the order shown or discussed.

[0054] The various exemplary methods described and / or illustrated herein may also omit one or more of the steps described or illustrated herein, or include additional steps in addition to the disclosed steps. Further, the steps of any method disclosed herein may be combined with any one or more steps of any other method disclosed herein.

[0055] Unless otherwise specified, the terms "connected to" and "coupled to" (and their derivatives) as used in the specification and claims shall be interpreted to allow both direct and indirect (i.e., via other elements or components) connection. Further, the term "a" or "an" as used in the specification and claims shall be interpreted to mean "at least one". Finally, for convenience of use, the terms "comprising" and "having" (and their derivatives) as used in the specification and claims may be interchanged with the word "including" and shall have the same meaning as the word "including".

[0056] As used herein, the term "or" is inclusively used to refer to alternatives and combinations of alternatives. As used herein, characters such as numbers refer to like elements, typically the first number corresponding to the figure number and the remaining numbers corresponding to like elements in other figures.

[0057] Embodiments of the present disclosure have been shown and described as herein described, and are provided only by way of example. Those of ordinary skill in the art will recognize many adaptations, alterations, variations, and substitutions without departing from the scope of the present disclosure. Several alternatives and combinations of the embodiments disclosed herein may be used without departing from the scope of the present disclosure and the present invention. Several alternatives and combinations of the embodiments disclosed herein may be used without departing from the scope of the present disclosure and the invention disclosed herein. Accordingly, the scope of the invention of the present disclosure is defined only by the scope of the appended claims and their equivalents.

Claims

1. A tamper for compressing coffee grounds in a filter basket, characterized in that, the tamper comprises: a handle; and a tamper head connected to the handle, wherein the tamper head includes a continuous first surface connected by a sidewall (116) and a continuous second surface opposite the first surface, the first surface being the upper surface (112) of the tamper head, and the second surface being the bottom surface (114) of the tamper head; and wherein the sidewall (116) tapers from a first diameter (D1) adjacent the first surface to a second diameter (D2) adjacent the second surface, the second diameter (D2) being smaller than the first diameter (D1).

2. The tamper according to claim 1, wherein, the first surface is connected to the handle.

3. The tamper according to claim 1, wherein, the tamper further includes a transition portion between the sidewall and the second surface.

4. The tamper according to claim 3, wherein, the transition portion defines a fillet radius.

5. The tamper according to claim 4, wherein, the fillet radius is between 0.06 mm and 6.35 mm.

6. The tamper according to claim 1, wherein, the sidewall includes one or more annular grooves formed therein.

7. The tamper according to claim 1, wherein, the sidewall taper is constant.

8. The tamper according to claim 1, wherein, the handle is connected to the tamper head by a threaded connection portion.

9. The tamper according to claim 8, wherein, the threaded connection portion is a threaded protrusion integrally formed with the tamper head, and the handle includes a threaded recess for receiving the threaded protrusion.

10. The tamper according to claim 8, wherein, the threaded connection portion is a threaded protrusion formed in the handle, and the tamper head includes a threaded recess for receiving the threaded protrusion.

11. The tamper according to claim 1, wherein, the second surface defines a radius of curvature.

12. The tamper according to claim 1, wherein, the second surface is hemispherical.

13. The tamper according to claim 1, wherein, the tamper is attached to a mechanical tamping device.

14. The tamper according to claim 13, wherein, the mechanical tamping device is electrically driven.

15. The tamper according to claim 13, wherein, the mechanical tamping device is manually driven.

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