Bean grinding device

Abstract

A bean grinding device (2) comprising: a main body (4); a pair of opposed abrasive grindstones (6, 8) mounted in the body (4), including a non-rotating abrasive grindstone (6) and a rotationally driven abrasive grindstone (8), the rotationally driven abrasive grindstone (8) having an axis of rotation; a drive motor (90) operatively coupled via a drive shaft (10) to the rotationally driven abrasive tool (8); an abrasive flow path defined within the body (4); and a discharge nozzle (48) having an outlet and an inlet in communication with the abrasive flow path; the non-rotating grinding grindstone (6) and the rotationally driven grinding grindstone (8) each define a respective substantially flat grinding surface; the grinding surfaces face each other; planes defined by the grinding surfaces of the grinding grindstone are parallel to each other and perpendicular to the rotation axis; the proximal end of the drive shaft (10) is connected to a drive motor (90) via a gearbox (92); and the offset of the rotationally driven abrasive tool (8) relative to the axis of rotation is resisted on one side by a drive shaft (10) supported in a drive shaft bearing and on the opposite side by a support shaft (18) extending from the rotationally driven abrasive tool (8), with the distal end of the support shaft (18) supported in a support shaft bearing assembly carried by the body (4).

Description

Technical Field

[0001] The present invention relates to a bean grinding device, such as a coffee bean grinder. Background Art

[0002] High-quality beverages, such as coffee, are best prepared using precisely metered quantities of freshly ground, roasted coffee beans. To this end, it is desirable to provide a grind flow path that is as close to vertical as possible and free of any areas where grinds can accumulate and become trapped. Mechanically, it is also desirable to drive the rotary-actuated grinder / burr from below and to mount the drive motor as close to the grinder as possible.

[0003] For example, WO 2018 / 211264 and US Pat. No. 2,522,643 disclose conventional bean grinding devices. In such devices, concentric grinding tools are typically used for grinding. Specifically, an inner grinding tool has an outward-facing frusto-conical grinding surface, while an outer grinding tool has an inward-facing frusto-conical grinding surface. The beans are ground between the two adjacent grinding surfaces. For grinding devices using concentric grinding tools, maintaining the concentricity of the inner and outer grinding tools is crucial for consistent grinding.

[0004] However, in some cases it is desirable to grind the beans using a flat burr / disc. When using a flat burr, maintaining a parallel relationship between the opposing grinding surfaces is important to ensure consistent grinding action and a consistent output of fine ground particles. Summary of the Invention

[0005] The object of the present invention is to provide an improved bean grinding device that uses a flat grinder / grinding disc (ie, a grinder with a flat grinding surface).

[0006] According to a first aspect of the present invention, there is provided a bean grinding device comprising: a main body; a pair of opposing grinding tools mounted in the main body, the grinding tools comprising a rotationally fixed / non-rotatable grinding tool and a rotationally driven grinding tool, the rotationally driven grinding tool having a rotation axis about which the rotationally driven grinding tool rotates; a drive motor operatively coupled to the rotationally driven grinding tool via a drive shaft; a ground material flow path defined within the main body; and a discharge nozzle having an outlet and an inlet communicating with the ground material flow path. wherein the non-rotating grinding tool and the rotationally driven grinding tool each define a respective substantially planar grinding surface; the grinding surfaces face each other; the planes defined by the grinding surfaces of the grinding tools are parallel to each other and perpendicular to the rotation axis; the proximal end of the drive shaft is connected to the drive motor via a gear box; and deflection / deflection of the rotationally driven grinding tool relative to the rotation axis is resisted on one side by the drive shaft supported in the drive shaft bearing and on the opposite side by a support shaft extending from the rotationally driven grinding tool, wherein the distal end of the support shaft is supported in a support shaft bearing assembly carried by the body.

[0007] It will be appreciated that in order to maintain the parallel relationship between the opposing planar grinding surfaces, it is important to prevent the rotatably driven grinding tool from lateral movement, displacement or tilting relative to its axis of rotation. Therefore, the rotatably driven grinding tool is supported on opposite sides thereof by spaced-apart bearings disposed within the body.

[0008] The grinding tool is suitably disposed within a grinding chamber defined by the device body.

[0009] In one embodiment of the present invention, a rotationally driven grinding tool is carried by a rotationally driven tool holder, wherein the tool holder includes a main body portion defining a central passageway / bore, and the distal end portion of the drive shaft is located within the central passageway / bore. Suitably, the rotationally driven tool holder is rotationally locked relative to the drive shaft. For example, the rotationally driven tool holder may be keyed to the distal end portion of the drive shaft located within the central passageway, or the drive shaft may form an interference fit with the tool holder, or the drive shaft may be welded or adhesively bonded to the rotationally driven tool holder.

[0010] The support shaft suitably extends axially from the main body of the rotationally driven mold support. The support shaft and the main body of the rotationally driven mold support may be separate components or may be an integral component. For example, the rotationally driven mold support and the support shaft may be a single component formed in one piece or manufactured in another manner.

[0011] In another embodiment of the present invention, the support shaft includes a main body portion and a distal portion. Both the main body portion and the distal portion may be cylindrical. Optionally, the diameter of the distal portion is smaller than the diameter of the main body portion.

[0012] By reducing the diameter of the distal end portion of the support shaft, a smaller sized bearing assembly may be used to rotationally support the support shaft without affecting the overall strength of the support shaft.

[0013] Suitably, the distal end portion of the support shaft is rotatably received within the support shaft bearing assembly.

[0014] In order to reduce the friction between the distal end portion of the support shaft and the support shaft bearing assembly, the distal end portion of the support shaft may include a sleeve. The sleeve may be locked in the rotational direction relative to the distal end portion of the support shaft, in which case the sleeve may rotate within the support shaft bearing assembly; or the distal end portion of the support shaft may rotate within the sleeve (i.e., the sleeve is linked to the distal end portion of the support shaft in the rotational direction), in which case the sleeve may be fixed within the support shaft bearing assembly. It will be understood that the friction between the sleeve and the bearing assembly, or the friction between the sleeve and the distal end portion of the support shaft, is appropriately less than the friction between the distal end portion of the support shaft and the bearing assembly. Therefore, the sleeve may be a friction-reducing sleeve.

[0015] The sleeve is suitably made of a different material than the support shaft. For example, the support shaft may be made of aluminum, while the sleeve may be made of steel or a polymeric material having a relatively low coefficient of friction, such as polytetrafluoroethylene (PTFE).

[0016] In one embodiment of the present invention, the support shaft can extend through the non-rotating abrasive tool but not engage it. In other words, the non-rotating abrasive tool can be carried by a non-rotating tool support, which defines a through hole therethrough, and the support shaft can extend through the through hole defined by the non-rotating tool support and maintain an appropriate spacing therefrom. In this configuration, the support shaft can freely rotate relative to the non-rotating abrasive tool / non-rotating tool support.

[0017] In another embodiment of the present invention, a support shaft bearing assembly includes a central body portion defining a bore therein for rotatably receiving a distal end portion of a support shaft (and optionally a sleeve); an outer retaining ring; and a plurality of connecting arms connecting the central body portion to the outer retaining ring. In this manner, the central body portion can be aligned with the axis of rotation of the drive shaft, while the outer retaining ring can be secured to the device body. The connecting arms maintain the central body portion, and therefore the distal end of the support shaft, in a fixed position relative to the device body. This prevents or reduces lateral movement or displacement of the distal end of the support shaft, thereby maintaining a parallel relationship between the grinding tools.

[0018] In one embodiment of the present invention, each connecting arm is in the shape of an inverted V. That is, the bifurcated end of each connecting arm faces the drive motor and the apex of each connecting arm faces upwards. Suitably, the connecting arms gradually expand / taper outwards from the central body portion to the outer positioning ring. Thus, the width of the connecting arms can gradually increase from the central body portion to the outer positioning ring. In addition to maintaining the central body portion in the desired position, the connecting arms arranged in this way can also have other functions. For example, the connecting arms can prevent or reduce the so-called "bean popping" phenomenon, that is, beans or partially ground beans are pushed upwards and escape from the top of the device during the grinding process. The connecting arms can help deflect these beans or partially ground beans back into the interior of the device, for example towards the grinding chamber of the device where the grinding tool is arranged. In addition or as an alternative, the connecting arms can also reduce the noise during the grinding process by reflecting or deflecting sound waves generated by the device during the grinding process.

[0019] The central body portion of the support shaft bearing assembly may be of tapered configuration. Thus, the central body portion may have a curved upper surface and a base portion, the base portion optionally being of planar configuration. The through hole is suitably formed in the base portion.

[0020] In yet another embodiment of the present invention, the apparatus further comprises a bean hopper having a tapered surface and a bean guide channel surface, the tapered surface being inclined toward the central body portion of the support shaft bearing assembly, wherein the bean guide channel surface is arranged parallel to an outwardly facing surface of the central body portion; and wherein the bean guide channel surface and the outwardly facing surface of the central body portion together define a bean inlet channel, and wherein a gap between the outwardly facing surface of the central body portion and the bean guide channel surface is constant.

[0021] By controlling the flow of beans, the grinding tools are prevented from becoming clogged and the drive motor is prevented from being overloaded. For example, the gap between the bean guide surface and the outwardly facing surface of the central body portion can be between 5 mm and 20 mm, such as 7 mm to 18 mm or 10 mm to 15 mm. Those skilled in the art will appreciate that this gap can be a predetermined gap, depending on the average size of the beans to be ground.

[0022] It will be appreciated that the bean guiding surface may be formed as an undercut of the conical surface of the bean hopper.

[0023] In embodiments where the central body portion is conical, the bean guiding surface may be in the form of an inverted frusto-conical structure, wherein the two conical surfaces are parallel to each other.

[0024] The angled nature of the bean guide surface relative to the outwardly facing surface of the central body portion of the upper bearing means that the bean guide surface can vertically overlap a portion of the central body portion. In such embodiments, the bean inlet passage is angled relative to the vertical plane. This arrangement helps reduce or prevent the risk of "bean popping" while also helping to reduce noise during the grinding process.

[0025] In another embodiment of the present invention, the substantially flat grinding surface of each grinding tool is suitably provided with grinding teeth. It is understood that when the rotationally driven grinding tool rotates relative to the non-rotating grinding tool, the opposing grinding teeth carried by the flat grinding surface can achieve gripping and grinding of the beans.

[0026] In such an embodiment, the non-rotating grinding tool and the rotationally driven grinding tool each have a circular cross-section, wherein the substantially flat grinding surface of each grinding tool is disposed about a peripheral edge portion of the respective grinding tool, for example, a peripheral edge portion of each grinding tool. Thus, beans can enter the grinding chamber defined by the device body at a position radially inward of the grinding surface of the grinding tool and can be directed or pushed radially outward toward the oppositely disposed planar grinding surface.

[0027] In another embodiment of the present invention, the non-rotating grinding tool and the rotationally driven grinding tool each include a pre-grinding portion, the pre-grinding portion being disposed radially inwardly of the grinding surface. Suitably, the pre-grinding portion is tapered toward the grinding surface. For example, the pre-grinding portion may be truncated cone-shaped or trumpet-shaped, such that the pre-grinding portions collectively define a funnel that tapers toward the grinding surface of the grinding tool.

[0028] Thus, the grinding tool and / or the grinding tool holder may jointly define a central cavity for receiving the beans. A conical pre-grinding portion of the grinding tool is provided radially outside the central cavity, wherein the spacing between corresponding portions of the grinding tool decreases; and an oppositely planar grinding surface is provided radially outside the pre-grinding portion of the grinding tool.

[0029] Suitably, the pre-grinding section begins to break up the beans and start the grinding process before the partially ground beans are directed or pushed towards the grinding surface where they are finally ground to a desired grind fineness.

[0030] In an embodiment of the present invention, the pre-grinding portion of the grinding tool includes grinding teeth. Therefore, both the grinding surface and the pre-grinding portion of the grinding tool may include grinding teeth. When the rotationally driven grinding tool rotates relative to the non-rotating grinding tool, the grinding teeth of the pre-grinding portion of the grinding tool can grip and grind the beans.

[0031] The grinding teeth may be constructed or arranged to prevent or inhibit beans that have entered the pre-ground portion of the grinding burr from moving radially inward, for example, back into the central cavity.

[0032] As described above, the beans can be guided or pushed radially outward toward the pre-grinding section. Therefore, the rotationally driven grinder holder can carry the rotationally driven grinding grinder; wherein the rotationally driven grinder holder includes a guide portion disposed radially inwardly of the rotationally driven grinding grinder, wherein the guide portion includes one or more guide ribs that guide unground beans or bean fragments toward the rotationally driven grinding grinder. In such an embodiment, the guide ribs suitably push the beans toward the pre-grinding section of the grinding grinder. Suitably, the guide ribs are curved, such that the rotational motion of the rotationally driven grinding grinder pushes the beans radially outward, i.e., toward the pre-grinding section of the grinding grinder. It should be understood that in such an embodiment, the rotationally driven grinding grinder can be annular, with a central void or cavity defined by the grinding grinder. The guide portion can be disposed within the central void or cavity defined by the rotationally driven grinding grinder.

[0033] To facilitate maintenance or replacement, the rotationally driven grinding tool and / or the non-rotating grinding tool can be arranged as part of a grinding tool subassembly. For example, a rotationally driven grinding tool support, a rotationally driven grinding tool, a support shaft, and an optional guide portion can define a rotating grinding tool subassembly. In such an embodiment, the rotating grinding tool subassembly is suitably rotationally fixed relative to the drive shaft. For example, the rotating grinding tool subassembly can be keyed to the drive shaft, wherein the grinding tool subassembly rotates with the drive shaft. In this arrangement, the rotating grinding tool subassembly can be quickly and easily replaced as a single unit or component.

[0034] In a similar arrangement to the rotationally driven grinding tool, the non-rotating tool holder can carry the non-rotating grinding tool. As with the rotationally driven grinding tool, the non-rotating tool holder can be connected to a support shaft bearing assembly; wherein the non-rotating tool holder, the non-rotating grinding tool, and the support shaft bearing assembly together define a fixed grinding tool subassembly. Again, this allows the fixed grinding tool subassembly to be quickly and easily replaced as a single unit or component.

[0035] Suitably, the non-rotating grinding tool is paired with a specific rotationally driven grinding tool. Thus, for a different pair of grinding tools, both the rotating grinding tool subassembly and the fixed grinding tool subassembly can be quickly and easily replaced together. It will be appreciated that the grinding tools in a pair can have different grinding profiles. For example, the grinding tool in one pair can produce a finer grind (i.e., smaller particles) than the grinding tools in another different pair.

[0036] Because users may wish to vary the fineness of grind they can achieve, it may be desirable to provide a bean grinding device with two independent pairs of grinding grinds. Therefore, the present invention may further include a second rotationally driven grinding grind subassembly and a second fixed grinding grind subassembly. In such an embodiment, the first pair of grinding grinds can be quickly and easily replaced with the second pair of grinding grinds simply by removing the first rotationally driven grinding grind assembly and the first fixed grinding grind assembly, then connecting the second rotationally driven grinding grind assembly to the drive shaft and the second fixed grinding grind assembly to the device body. Therefore, in this embodiment, the present invention may be in the form of a kit comprising a bean grinding device as defined herein; a second rotationally driven grinding grind subassembly; and a second fixed grinding grind subassembly, wherein the second rotationally driven grinding grind subassembly and the second fixed grinding grind subassembly may be as defined herein.

[0037] Each pair of grinding tool subassemblies may include markings to indicate the correct pairing for the grinding tools to avoid pairing a first grinding tool with a second grinding tool.

[0038] In an embodiment of the present invention, the apparatus further comprises a first material guiding element positioned below the grinding tool, wherein the first material guiding element comprises one or more fingers that generate an airflow to sweep the grinding material into a material flow path. Thus, the first material guiding element can be positioned within a grinding chamber defined by the apparatus body. The material flow path is suitably in communication with (i.e., can lead to) the grinding chamber. For example, the apparatus can define a cavity within the grinding chamber below the grinding tool, and the first material guiding element can be positioned within this cavity. In this manner, grinding material that falls into the cavity is subsequently swept or propelled into the material flow path. The first material guiding element can be in the form of an arm carried by the underside of a rotationally driven grinding tool support. The arm can extend from a point near the center of the grinding tool support to a peripheral edge portion of the grinding tool support. Alternatively, the arm can be a linear arm. The arm can sweep backward or be angled from a radius defined by the grinding tool support. In the context of the present invention, the term "rearward" is defined relative to the direction of rotation of the grinding tool support.

[0039] In addition to or as an alternative to the first material guiding element, the apparatus may further include one or more second material guiding elements positioned radially outwardly of the grinding tool, wherein the one or more second material guiding elements include a body that sweeps the grinding material into the material flow path. Thus, within the grinding chamber, an annular channel may be defined between the grinding tool / tool ​​support and the outer wall of the grinding chamber, and grinding material deposited within this annular channel may be swept into the material flow path by the one or more second material guiding elements. In such an embodiment, the body of the or each second material guiding element is shaped so that it tapers outwardly or inwardly from a leading edge or a trailing edge. In other words, the second material guiding element may be wedge-shaped. Suitably, the or each second material guiding element is carried by a rotationally driven grinding tool support. The or each second material guiding element may include a leading edge portion extending outwardly from the outer peripheral wall of the grinding tool support and a trailing edge portion that tapers toward the grinding tool support. It has been found that if the leading edge portion extends radially outward, this can result in grinding material accumulating in front of the leading edge. Thus, the leading edge portion of the or each second article guiding element may be swept rearwardly. For example, the leading edge portion may be angled rearwardly by 10° to 40° relative to the radius of the tool holder. For example, the angle defined between the leading edge portion and the radius may be 15° to 25°. Those skilled in the art will appreciate that, in the context of the present invention, the term "rearwardly" relates to the direction of rotation of the tool holder in use.

[0040] Suitably, the first and / or second material guiding element is driven in rotation by a drive motor. In this way, the first and / or second material guiding element can rotate together with the rotationally driven grinding tool. For example, the first and / or second material guiding element can form part of the rotationally driven grinding tool support.

[0041] The apparatus suitably comprises a bean inlet defined above the grinding burrs and an inlet flow path defined from the bean inlet to the grinding chamber.The bean inlet is suitably defined by a hopper.

[0042] The drive motor is suitably connected to a drive shaft via a gearbox. The gearbox allows the drive shaft to rotate at a different speed than the output shaft of the drive motor. Commercially available drive motors typically have a fixed rotational speed for a given power input, and this rotational speed may not be suitable for the device's drive shaft. It has been found that if the rotationally driven grinding burrs rotate too quickly, the grounds push against the side walls of the grinding chamber and may accumulate there. Furthermore, if the beans are ground at too high a speed, significant heat may be generated in the grinding chamber, causing the grounds to "burn," which degrades the flavor of the ground beans. Finally, the noise and vibration of the device may increase as the rotational speed of the drive shaft increases. Conversely, if the rotationally driven grinding burrs rotate too slowly, the beans may not be properly pushed into the grinding portion of the grinding burrs, which may result in the beans being unground or insufficiently ground in the device. In view of the foregoing, a suitable rotational speed for the drive shaft of the present invention may be 400 to 800 rpm, for example, 450 to 750 rpm or 500 to 700 rpm. Therefore, the gearbox suitably provides the drive shaft with a rotational speed within a desired range.It will be appreciated that the gearbox may be a reduction gearbox which provides the drive shaft with a slower rotational speed than the drive motor.

[0043] In one embodiment of the present invention, the apparatus further comprises a rotationally fixed tool adjustment mechanism that adjusts the axial position of the non-rotating grinding tool relative to the rotationally driven grinding tool. Thus, the rotationally fixed tool adjustment mechanism can change the spacing or gap between the non-rotating grinding tool and the rotationally driven grinding tool. Thus, the fineness of the grinding material can be adjusted by adjusting the axial spacing between the non-rotating grinding tool and the rotationally driven grinding tool. For example, the non-rotating grinding tool can be carried by a non-rotating tool support; the non-rotating tool support can include a first threaded portion; the non-rotating tool support includes the first threaded portion; and the apparatus includes a rotatable second threaded portion threadedly engaged with the first threaded portion, wherein rotation of the second threaded portion (e.g., by a user) causes the non-rotating tool support to be displaced axially relative to the axis of rotation. Suitably, the non-rotating tool support is locked against rotation. In other words, when the second threaded portion is rotated, the non-rotating tool support is prevented from rotating. Since the non-rotating grinder carrier is suitably locked against rotation, it can only move axially in response to rotation of the second threaded portion.

[0044] The tapping nozzle suitably extends downwardly from the body.In addition, the tapping nozzle suitably defines a longitudinal axis.

[0045] In one embodiment of the present invention, an inverted V-shape is formed by the rotation axis of the drive shaft and the longitudinal axis of the discharge nozzle.

[0046] Suitably, the axis of rotation is coaxial with the longitudinal axis of the body, whereby the longitudinal axis of the tap nozzle is at an angle relative to the longitudinal axis of the body.

[0047] The angle defined between the axis of rotation and the longitudinal axis of the tapping nozzle may be 5° to 80°, suitably 10° to 70°, 10° to 60°, 10° to 50°, 15° to 45° or 15° to 30°.

[0048] The axis of rotation may intersect the longitudinal axis of the tap nozzle, with the point of intersection suitably located within the body.

[0049] Both the axis of rotation and the longitudinal axis of the tap nozzle may be at an angle relative to a vertical plane.

[0050] The angle between the axis of rotation and the longitudinal axis of the tap nozzle may have a substantially vertical bisector.

[0051] In one embodiment of the present invention, the apparatus comprises a base member, wherein the body of the apparatus is coupled to one end of the base member, and an opposite end of the base member defines a grounds collector aperture. The grounds collector aperture suitably receives a grounds collector that is removable from the aperture. The grounds collector aperture is suitably located vertically below the outlet of the discharge nozzle.

[0052] It is known that grinding beans, such as coffee beans, can generate relatively high levels of static charge on the resulting finely ground particles, particularly under certain weather conditions. It has generally been found that the finer the grind, the greater the static charge generated. Fine grinds are very lightweight and therefore significantly affected by the applied static charge. This can cause the grind to adhere to surfaces of the grinding device or be pushed away from the grinding device.

[0053] To address this issue, a grounds collector platform can be located on the base member, wherein the grounds collector platform is located below the outlet of the discharge nozzle, defines a grounds collector receptacle, and is formed from wood. The grounds collector platform can define the grounds collector aperture described above. Using a wooden grounds collector receptacle prevents or minimizes the accumulation of static charge.

[0054] In an embodiment of the present invention, the grounds collector platform is spaced apart from the device body.

[0055] The wooden grounds collector platform may be a two-part component comprising a lower portion fixed to the base member and a removable upper portion.

[0056] The discharge nozzle may be formed from a polymeric material or a metallic material.

[0057] The device body may be formed of a polymer material or a metal material.

[0058] The apparatus may include a grounds collector shaped to be received by the grounds collector receptacle. The grounds collector may be formed from a polymeric material or a metallic material.

[0059] The device may further comprise a foot provided on the underside of the base element. The foot is also suitably formed of wood. The foot may comprise a bottom defining a friction surface.

[0060] The use of wood for the grounds collector platform and optionally for the feet greatly reduces or eliminates problems associated with static charging of the grounds.

[0061] According to another embodiment of the present invention, the device further comprises a reservoir (e.g., a bean hopper) in communication with the grinding chamber via an inlet flow path, wherein the grinding tools are located within the grinding chamber, wherein the reservoir is defined by a reservoir body. The grinding device further comprises a lid hingedly coupled to the reservoir body and having a closed configuration in which the reservoir is covered by the lid and access to the reservoir is prevented, and an open configuration in which access to the reservoir is allowed. Additionally, the drive motor comprises a fixed switch having an operating position in which the motor is allowed to operate and a deactivated position in which the motor is prevented from operating. In such embodiments, the lid comprises a switch engagement element, wherein the switch engagement element positions the fixed switch in the operating position when the lid is in its closed configuration.

[0062] In one embodiment of the present invention, the fixed switch is biased to its inoperative position.

[0063] When in its off position, the fixed switch suitably cuts off power to the motor.

[0064] In yet another embodiment of the present invention, the switch engaging member includes a protruding rod, and the stationary switch defines a hole sized and configured to receive the protruding rod therein.

[0065] The reservoir may comprise an opening, and when in its closed configuration, the cover covers the entire opening of the reservoir.

[0066] In order to be able to see the amount of beans in the container, the lid may be transparent.

[0067] In yet another embodiment of the present invention, the lid and / or the reservoir body includes a latch configured to releasably retain the lid in its closed configuration.

[0068] In embodiments where the apparatus comprises a rotationally fixed abrasive tool adjustment mechanism as described above and the adjustment mechanism comprises a rotatable second threaded portion, the cover may cover the rotatable second threaded portion such that the rotationally fixed abrasive tool cannot move axially when the cover is in its closed configuration.

[0069] Those skilled in the art will appreciate that the support shaft may be formed as an extension of the drive shaft rather than as a separate component.

[0070] Therefore, according to a second aspect of the present invention, there is provided a bean grinding device comprising: a main body; a pair of opposing grinding tools mounted in the main body, the grinding tools comprising a non-rotating grinding tool and a rotationally driven grinding tool, the rotationally driven grinding tool having a rotation axis about which the rotationally driven grinding tool rotates; a drive motor operatively coupled to the rotationally driven grinding tool via a drive shaft; a ground material flow path defined in the main body; and a discharge nozzle having an outlet and communicating with the ground material flow path. an inlet of the drive shaft, wherein the non-rotating grinding tool and the rotationally driven grinding tool each define a respective substantially flat grinding surface; the grinding surfaces face each other; the planes defined by the grinding surfaces of the grinding tools are parallel to each other and perpendicular to the axis of rotation; the proximal end (i.e., the first end) of the drive shaft is connected to the drive motor via a gear box; and the device defines a drive shaft upper bearing assembly and a lower bearing, wherein the distal end (i.e., the second end or opposite end) of the drive shaft is rotatably supported in the drive shaft upper bearing assembly and the proximal portion of the drive shaft is rotatably supported in the lower bearing, wherein the lower bearing is in the form of a cylindrical sleeve retained within the housing.

[0071] All optional features defined and described herein in relation to the first aspect of the invention may form part of the second aspect of the invention.Thus, the invention defined in the second aspect of the invention may include one or more optional features defined herein in relation to the first aspect of the invention.

[0072] For example, in one embodiment of the present invention, a rotationally driven lapping tool is carried by a rotationally driven tool holder, wherein the tool holder includes an axially extending main body portion defining a central channel, and a central or middle portion of a drive shaft is positioned within the central channel, such that a distal portion of the drive shaft extends from a first end of the central channel and a proximal portion of the drive shaft extends from a second end of the central channel. It will be appreciated that the rotationally driven tool holder is suitably rotationally secured to the portion of the drive shaft positioned within the central channel of the tool holder. For example, the rotationally driven tool holder may be keyed to the central or middle portion of the drive shaft positioned within the central channel, or the drive shaft may be frictionally engaged with the rotationally driven tool holder or welded or adhered thereto.

[0073] In the context of the present invention, the proximal portion of the drive shaft is suitably the portion of the drive shaft that is closest to the drive motor.

[0074] By having two portions of the drive shaft extending from each end of the central passage, the drive shaft can be rotatably supported on either side of the rotatably driven mold support. This helps minimize lateral movement or displacement of the drive shaft relative to the axis of rotation. Thus, the portion of the drive shaft rotatably supported within the lower bearing can be defined by or form part of the proximal end portion of the drive shaft.

[0075] The lower bearing housing may be disposed between the gearbox and the rotationally driven grinding tool. Suitably, the lower bearing housing extends from the gearbox housing. It will be appreciated that the gearbox housing houses the gearbox. The lower bearing is suitably fixed relative to the lower bearing housing.

[0076] Optionally, the distal portion of the drive shaft includes a main body portion and a distal end portion, wherein the distal end portion has a smaller diameter than the main body portion. By reducing the diameter of the distal end of the drive shaft, a smaller bearing can be used to rotatably support the distal end of the drive shaft without compromising the overall strength of the drive shaft.

[0077] In one embodiment of the invention, the proximal portion and the central portion of the drive shaft have a diameter of 5mm to 20mm, for example 10mm to 15mm. Furthermore, the drive shaft is suitably formed of aluminum.

[0078] In order to reduce friction between the distal end of the drive shaft and the bearing assembly on the drive shaft, the distal end of the drive shaft may include a sleeve, wherein the sleeve suitably has a low coefficient of friction. Suitably, the sleeve is formed from steel, such as stainless steel.

[0079] In one embodiment of the present invention, the drive shaft may also extend through the non-rotating abrasive tool but not engage therewith. In other words, the non-rotating abrasive tool may be carried by a non-rotating tool support that defines a hole therethrough, and the drive shaft may extend through the hole defined by the non-rotating tool support and be suitably spaced therefrom. In another embodiment of the present invention, the rotationally driven tool support includes an axial extension through which the drive shaft extends, and the axial extension of the rotationally driven tool support may also extend through the hole defined by the non-rotating tool support.

[0080] As described above, the upper bearing assembly suitably includes a central body portion defining a bore therein for receiving the distal end of the drive shaft; an outer retaining ring; and a plurality of connecting arms connecting the central body portion to the outer retaining ring. The upper bearing assembly of the second aspect of the present invention may be substantially the same as the support shaft bearing assembly of the first aspect of the present invention.

[0081] Therefore, in one embodiment of the present invention, each connecting arm is shaped like an inverted V. In other words, the spaced-apart ends of each connecting arm face the drive motor, with the apex of each connecting arm facing upward. Suitably, the connecting arms also gradually widen outward from the central body portion to the outer retaining ring. Thus, the width of the arms can increase from the central body portion to the outer retaining ring. Connecting arms arranged in this manner can have other functions besides simply maintaining the central body portion in a desired position. For example, the connecting arms can prevent or minimize the so-called "bean popping," in which beans or partially ground beans are pushed upward and discharged from the top of the device during the grinding process. The connecting arms can help deflect such beans or partially ground beans back into the device, for example, toward the device's grinding chamber, where the grinding tools are located. Additionally or alternatively, the connecting arms can reduce noise from the grinding process by reflecting or deflecting sound waves generated by the device during the grinding process.

[0082] The apparatus may further include a bean hopper having an inverted tapered surface and a bean guide channel surface, the inverted tapered surface being inclined toward the central body portion of the upper bearing, wherein the bean guide channel surface is arranged parallel to the outward-facing surface of the central body portion; and wherein the bean guide channel surface and the outward-facing surface of the central body portion together define a bean inlet channel, and wherein the gap between the outward-facing surface of the central body portion and the bean guide channel surface is constant. Thus, the bean inlet channel may have a substantially constant width, wherein the width is the gap between the bean guide surface and the outward-facing surface of the central body portion. In such an embodiment, the tapered surface of the bean hopper directs beans to be ground toward the center of the hopper, and the bean inlet channel controls the flow of beans from the hopper to the grinding chamber.

[0083] The abrasive tool of the second aspect of the present invention may be as defined in the first aspect of the present invention, including any embodiment or optional feature thereof.

[0084] For example, a non-rotating lapping tool can be carried by a non-rotating tool holder. In another embodiment, the non-rotating tool holder is connected to an upper bearing assembly; wherein the non-rotating tool holder, the non-rotating lapping tool, and the upper bearing together define a fixed lapping tool subassembly. Again, this configuration allows for quick and easy replacement of the fixed lapping tool.

[0085] Aspects of the present invention may be defined according to the following definitions:

[0086] 1. A bean grinding device comprising:

[0087] main body;

[0088] a pair of opposed grinding tools mounted in the body, the grinding tools comprising a non-rotating grinding tool and a rotationally driven grinding tool, the rotationally driven grinding tool having a rotation axis about which the rotationally driven grinding tool rotates;

[0089] a drive motor operatively coupled to the rotationally driven abrasive tool via a drive shaft;

[0090] a grind flow path defined within the body; and

[0091] a discharge nozzle having an outlet and an inlet communicating with the grinding material flow path;

[0092] wherein the non-rotating grinding tool and the rotationally driven grinding tool each define a respective substantially flat grinding surface; the grinding surfaces face each other; the planes defined by the grinding surfaces of the grinding tools are parallel to each other and perpendicular to the rotation axis; the proximal end of the drive shaft is connected to the drive motor via a gear box; and

[0093] Deflection of the rotationally driven grinding tool relative to the axis of rotation is resisted on one side by a drive shaft supported in a drive shaft bearing and on the opposite side by a support shaft extending from the rotationally driven grinding tool, wherein the distal end of the support shaft is supported in a support shaft bearing assembly carried by the body.

[0094] 2. The bean grinding device according to definition 1, wherein the rotationally driven grinding tool is carried by a rotationally driven tool holder, wherein the tool holder includes a main body portion defining a central channel, and the distal portion of the drive shaft is located within the central channel.

[0095] 3. The bean grinding device according to definition 2, wherein the support shaft extends from the main body of the rotationally driven grinder support.

[0096] 4. The bean grinding device according to any one of definitions 1 to 3, wherein the support shaft includes a main body portion and a distal end portion, and wherein the distal end portion has a diameter smaller than a diameter of the main body portion.

[0097] 5. The bean grinding device according to definition 4, wherein the distal end portion of the support shaft is rotatably accommodated in the support shaft bearing assembly.

[0098] 6. The bean grinding device according to definition 5, wherein the distal end portion of the support shaft includes a sleeve fixed thereto.

[0099] 7. The bean grinding device of any one of definitions 1 to 6, wherein the support shaft bearing assembly comprises a central body portion defining a hole therein, the hole rotatably receiving the distal end portion of the support shaft therein; an outer locating ring; and a plurality of connecting arms connecting the central body portion to the outer locating ring.

[0100] 8. The bean grinding device according to definition 7, wherein each of the connecting arms is in an inverted V-shape.

[0101] 9. The bean grinding device according to definition 7 or 8, wherein the device further comprises a bean hopper having a tapered surface and a bean guide channel surface, the tapered surface being inclined toward the central body portion of the support shaft bearing assembly, wherein the bean guide channel surface is arranged parallel to the outwardly facing surface of the central body portion; and wherein the bean guide channel surface and the outwardly facing surface of the central body portion together define a bean inlet channel, and a gap between the outwardly facing surface of the central body portion and the bean guide channel surface is constant.

[0102] 10. The bean grinding device according to any one of definitions 1 to 9, wherein the substantially flat grinding surface of each of the grinding grinds comprises grinding teeth.

[0103] 11. The bean grinding device according to any one of definitions 1 to 10, wherein the non-rotating grinding tool and the rotationally driven grinding tool each have a circular cross-section, wherein the substantially flat grinding surface of each grinding tool is provided around a peripheral edge portion of the corresponding grinding tool.

[0104] 12. The bean grinding device according to definition 11, wherein the non-rotating grinding tool and the rotationally driven grinding tool each include a pre-grinding portion, the pre-grinding portion is arranged radially inward of the grinding surface, and the pre-grinding portion is tapered toward the grinding surface.

[0105] 13. The bean grinding device according to any one of definitions 2 to 12, wherein the rotationally driven grinder holder includes a guide portion provided radially inwardly of the rotationally driven grinding grinder, wherein the guide portion includes one or more guide ribs that guide unground beans toward the rotationally driven grinding grinder.

[0106] 14. The bean grinding device according to definition 13, wherein the guide rib is curved.

[0107] 15. The bean grinding device according to definition 13 or 14, wherein the rotationally driven grinder holder, the rotationally driven grinding grind, and the guide portion define a rotating grinding grind subassembly; and wherein the rotating grinding grind subassembly is keyed to the drive shaft, wherein the rotating grinding grind subassembly rotates together with the drive shaft.

[0108] 16. The bean grinding device according to any one of definitions 1 to 15, wherein the non-rotating grinder support carries the non-rotating grinding grinder.

[0109] 17. The bean grinding device of definition 16, wherein the non-rotating grinder support is coupled to the support shaft bearing assembly; wherein the non-rotating grinder support, the non-rotating grinding grind, and the support shaft bearing assembly together define a fixed grinding grind subassembly.

[0110] 18. The bean grinding device according to any one of definitions 1 to 17, wherein the device further comprises a first grind guide element located below the grinding tool, wherein the first grind guide element comprises one or more finger-shaped portions that generate an airflow to blow the grind into the grind flow path.

[0111] 19. The bean grinding device according to definition 18, wherein the device defines a cavity below the grinding tool, and the first grinding material guiding element is located in the cavity.

[0112] 20. The bean grinding device according to any one of definitions 1 to 19, wherein the device further comprises a second grinding material guide element arranged radially outside the grinding tool, wherein the second grinding material guide element comprises one or more conical protrusions, and the conical protrusions sweep the grinding material into the grinding material flow path.

[0113] 21. The bean grinding device according to any one of definitions 18 to 20, wherein the first grind guide element and / or the second grind guide element is driven in rotation by the drive shaft.

[0114] 22. The bean grinding device according to any one of definitions 1 to 21, wherein the device further comprises a rotationally fixed grinder adjustment mechanism, wherein the grinder adjustment mechanism adjusts the axial position of the non-rotating grinding grinder relative to the rotationally driven grinding grinder.

[0115] 23. The bean grinding device of definition 22, wherein the non-rotating grinding tool is carried by a non-rotating tool holder; the non-rotating tool holder includes a first threaded portion; and the device includes a rotatable second threaded portion threadedly engaged with the first threaded portion, wherein rotation of the second threaded portion causes displacement of the non-rotating tool holder in an axial direction relative to the rotation axis.

[0116] 24. The bean grinding device according to any one of definitions 1 to 23, wherein the discharge nozzle defines a longitudinal axis, and the longitudinal axis of the discharge nozzle is arranged at an angle relative to the rotation axis of the rotationally driven grinding tool.

[0117] 25. The bean grinding device according to definition 24, wherein the rotation axis and the longitudinal axis of the discharge nozzle are both arranged at an angle relative to a vertical plane.

[0118] 26. The bean grinding device according to definition 25, wherein the rotation axis and the longitudinal axis of the discharge nozzle form an inverted V shape.

[0119] 27. The bean grinding device according to any one of definitions 1 to 26, wherein the device further comprises a second non-rotating grinding tool and a second rotationally driven grinding tool, wherein the first non-rotating grinding tool and the first rotationally driven grinding tool are replaceable by the second non-rotating grinding tool and the second rotationally driven grinding tool.

[0120] 28. A bean grinding device comprising:

[0121] main body;

[0122] a pair of opposed grinding tools mounted in the body, the grinding tools comprising a non-rotating grinding tool and a rotationally driven grinding tool, the rotationally driven grinding tool having a rotation axis about which the rotationally driven grinding tool rotates;

[0123] a drive motor operatively coupled to the rotationally driven abrasive tool via a drive shaft;

[0124] a grind flow path defined within the body; and

[0125] A discharge nozzle having an outlet and an inlet connected to the grinding material flow path, wherein the non-rotating grinding tool and the rotationally driven grinding tool each define a corresponding substantially flat grinding surface; the grinding surfaces face each other; the planes defined by the grinding surfaces of the grinding tools are parallel to each other and perpendicular to the rotation axis; the proximal end of the drive shaft is connected to the drive motor via a gear box; and the device defines a drive shaft upper bearing assembly and a lower bearing, the distal end of the drive shaft is rotatably supported in the drive shaft upper bearing assembly, and the proximal portion of the drive shaft is rotatably supported in the lower bearing, wherein the lower bearing is in the form of a cylindrical sleeve retained in the housing.

[0126] 29. The bean grinding device according to definition 28, wherein the rotationally driven grinding tool is carried by a rotationally driven tool holder, wherein the tool holder includes a main body portion defining a central channel, and the middle portion of the drive shaft is located within the central channel, so that the distal portion of the drive shaft extends from a first end of the central channel and the proximal portion of the drive shaft extends from a second end of the central channel.

[0127] 30. The bean grinding device according to definition 29, wherein the distal portion of the drive shaft includes a main body portion and a distal end portion, and wherein the distal end portion has a diameter smaller than a diameter of the main body portion.

[0128] 31. The bean grinding device according to definition 30, wherein the distal end portion of the drive shaft is rotatably received within a bearing assembly on the drive shaft.

[0129] 32. The bean grinding device of any one of definitions 28 to 31, wherein the drive shaft upper bearing assembly comprises: a central body portion defining a hole therein for receiving the distal end of the drive shaft; an outer locating ring; and a plurality of connecting arms connecting the central body portion to the outer locating ring.

[0130] 33. The bean grinding device according to definition 32, wherein each connecting arm is in the form of an inverted V-shape.

[0131] 34. The bean grinding device according to definition 32 or 33, wherein the device further comprises a bean hopper having a tapered surface and a bean guide channel surface, the tapered surface being inclined toward the central body portion of the bearing assembly on the drive shaft, wherein the bean guide channel surface is arranged parallel to the outwardly facing surface of the central body portion; and wherein the bean guide channel surface and the outwardly facing surface of the central body portion together define a bean inlet channel, and a gap between the outwardly facing surface of the central body portion and the bean guide channel surface is constant.

[0132] 35. The bean grinding device according to any one of definitions 28 to 34, wherein the substantially flat grinding surface of each of the grinding tools comprises grinding teeth.

[0133] 36. The bean grinding device according to any one of definitions 28 to 35, wherein the non-rotating grinding tool and the rotationally driven grinding tool each have a circular cross-section, wherein the substantially flat grinding surface of each grinding tool is arranged around a peripheral edge portion of the corresponding grinding tool.

[0134] 37. The bean grinding device according to definition 36, wherein the non-rotating grinding tool and the rotationally driven grinding tool both include a pre-grinding portion, the pre-grinding portion is arranged radially inward of the grinding surface, and the pre-grinding portion is tapered toward the grinding surface.

[0135] 38. The bean grinding device according to any one of definitions 28 to 37, wherein a rotationally driven grinder holder carries the rotationally driven grinding grinder; wherein the rotationally driven grinder holder includes a guide portion provided radially inwardly of the rotationally driven grinder holder, wherein the guide portion includes one or more guide ribs, and the guide ribs guide unground beans toward the rotationally driven grinding grinder.

[0136] 39. The bean grinding device according to definition 38, wherein the guide rib is curved.

[0137] 40. The bean grinding device of definition 38 or 39, wherein the rotationally driven grinder holder, the rotationally driven grinding grind, and the guide define a rotating grinding grind subassembly; and wherein the rotating grinding grind subassembly is keyed to the drive shaft, wherein the subassembly rotates with the drive shaft.

[0138] 41. The bean grinding device according to any one of definitions 28 to 40, wherein a non-rotating grinder support carries the non-rotating grinding grinder.

[0139] 42. The bean grinding device of definition 41, wherein the non-rotating grinder support is coupled to the upper bearing; wherein the non-rotating grinder support, the non-rotating grinding grind, and the upper bearing together define a fixed grinding grind subassembly.

[0140] 43. The bean grinding device according to any one of definitions 28 to 42, wherein the device further comprises a first grind guide element located below the grinding tool, wherein the first grind guide element comprises one or more finger-like portions that generate an airflow to blow the grind into the grind flow path.

[0141] 44. The bean grinding device of definition 43, wherein the device defines a cavity below the grinding tool, and the first grounds guiding element is located within the cavity.

[0142] 45. The bean grinding device according to any one of definitions 28 to 44, wherein the device further comprises a second grind guide element positioned radially outside the grinding tool, wherein the second grind guide element comprises one or more conical protrusions that sweep the grind into the grind flow path.

[0143] 46. ​​The bean grinding device according to any one of definitions 43 to 45, wherein the first and / or second grounds guiding element is driven in rotation by the drive shaft.

[0144] 47. The bean grinding device according to any one of definitions 28 to 46, wherein the device further comprises a rotationally fixed grinder adjustment mechanism that adjusts the axial position of the non-rotating grinding grinder relative to the rotationally driven grinding grinder.

[0145] 48. The bean grinding device of definition 47, wherein the non-rotating grinding tool is carried by a non-rotating tool holder; the non-rotating tool holder includes a first threaded portion; and the device includes a rotatable second threaded portion threadedly engaged with the first threaded portion, wherein rotation of the second threaded portion causes displacement of the non-rotating tool holder in an axial direction relative to the rotation axis.

[0146] 49. The bean grinding device according to any one of definitions 28 to 48, wherein the discharge nozzle defines a longitudinal axis, and the longitudinal axis of the discharge nozzle is at an angle relative to the rotation axis of the rotationally driven grinding tool.

[0147] 50. The bean grinding device according to definition 49, wherein the rotation axis and the longitudinal axis of the discharge nozzle are both at an angle relative to a vertical plane.

[0148] 51. The bean grinding device according to definition 50, wherein the rotation axis and the longitudinal axis of the discharge nozzle form an inverted V shape.

[0149] 52. The bean grinding device according to any one of definitions 28 to 51, wherein the device further comprises a second non-rotating grinding tool and a second rotationally driven grinding tool, wherein the first non-rotating grinding tool and the first rotationally driven grinding tool are replaceable by the second non-rotating grinding tool and the second rotationally driven grinding tool.

[0150] The skilled person will understand that the features described and defined in conjunction with the various aspects of the present invention and its embodiments may be combined in any combination, regardless of whether a particular combination is explicitly mentioned herein. Therefore, all such combinations are considered to be available to the skilled person. BRIEF DESCRIPTION OF THE DRAWINGS

[0151] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0152] Figure 1 is a perspective view of a bean grinding device according to the first aspect of the present invention;

[0153] Figure 2 yes Figure 1 a cross-sectional view of the bean grinding device shown;

[0154] Figure 3 is formed Figure 1 A perspective view of a lower grinder support that is a portion of the bean grinding apparatus is shown;

[0155] Figure 4 yes Figure 3 a perspective view of the lower tool holder shown with the lower lapping tool secured thereto;

[0156] Figure 4a yes Figure 4 a perspective view of the lower grinder support shown with the bean guide elements removed to illustrate the key connection structure;

[0157] Figure 5 It is from Figure 4 A perspective view of the lower mold support shown as viewed from below;

[0158] Figure 6 is a perspective view of the upper mold support and the top mounting member viewed from above, which form Figure 1 A portion of the bean grinding device shown in ;

[0159] Figure 7 yes Figure 6 A perspective view of the upper mold support shown as viewed from below;

[0160] Figure 8 It can be used as Figure 1 A portion of the illustrated apparatus provides a perspective view of two pairs of lapping tools and their associated tool supports;

[0161] Figure 9 is a cross-sectional view through a bean grinding device according to a second aspect of the present invention;

[0162] Figure 10 is formed Figure 9 A perspective view of a lower grinder support that is a portion of the bean grinding apparatus is shown;

[0163] Figure 11 yes Figure 10 a perspective view of the lower tool holder shown with the lower lapping tool secured thereto; and

[0164] Figure 12 It can be used as Figure 9 A portion of the apparatus is shown providing a perspective view of two pairs of lapping tools and their associated tool supports. DETAILED DESCRIPTION

[0165] For the avoidance of doubt, the skilled person will understand that in this specification, the terms "upper", "lower", "front", "rear", "upper", "lower", "width" and the like refer to the orientation in which the components as seen in the examples would be when mounted as shown in the figures for normal use.

[0166] The bean grinding device of the present invention is similar to the grinding device disclosed in WO2018 / 211264. The primary difference between the present invention and the device disclosed in WO2018 / 211264 lies in the grinding devices and how they are supported within the device body. All other features, such as the lid, motor, gearbox, base, etc., are as described in WO2018 / 211264.

[0167] As shown, the bean grinding device 2 comprises a body 4 in which is housed a rotationally fixed / non-rotating upper grinding burr 6 and a complementary rotationally driven lower grinding burr 8. The grinding burrs 6, 8 are commercially available from Italmill Grinding Technology.

[0168] The lower grinding tool 8 is carried on a drive shaft 10 which is rotatably supported in a lower bearing 12. The drive shaft 10 defines the axis of rotation of the lower grinding tool 8. The upper bearing 14 is defined within a top mount 16 which will be described in more detail below.

[0169] like Figure 2 、 Figure 4 and Figure 4a As shown, the lower grinding tool 8 is supported by a lower grinding tool holder 20. The lower grinding tool holder 20 includes a support shaft portion 18 that protrudes axially upward. The support shaft portion 18 includes a proximal cylindrical portion 18a and a distal cylindrical portion 18b, wherein the diameter of the distal cylindrical portion 18b is smaller than the diameter of the proximal cylindrical portion 18a. The distal cylindrical portion 18b is adapted to be rotatably received within the upper bearing 14. However, since the lower grinding tool holder is made of aluminum, a sleeve 22 made of stainless steel surrounds the distal cylindrical portion 18b, as this results in a lower coefficient of friction within the upper bearing 14.

[0170] refer to Figure 2 and Figure 4a, the key element 24 is located in a keyway 26 defined by the proximal cylindrical portion 18a of the support shaft portion 18 and a corresponding keyway 28 defined by the drive shaft 10. In this way, the lower mold carrier 20 is rotationally locked relative to the drive shaft 10.

[0171] To further secure the support shaft portion 18 to the drive shaft 10 , a screw 18 c passes through the distal end of the support shaft portion 18 and is threadedly coupled to an internal thread defined by the distal end portion of the drive shaft 10 .

[0172] The central portion 30 of the top mount 16 is conical in shape and is located within the bean hopper 32. The central portion 30 of the top mount 16 defines three apertures 16b through which beans can exit the hopper 32 and descend under gravity into the grinding chamber 34. The central portion 30 also defines an upper bearing 14 on its underside in which the distal cylindrical portion 18b of the support shaft portion 18 and its associated sleeve 22 are rotatably received.

[0173] The bean hopper 32 has a first inclined portion 32a that slopes downward toward the central aperture defined by the bean hopper 32. The bean hopper also has a second inclined portion 32b that is arranged parallel to the tapered central portion 30 of the top mount 16. The second inclined portion 32b defines an undercut relative to the first inclined portion 32a of the hopper 32. By arranging the second inclined portion 32b of the hopper 32 parallel to the tapered central portion 30 of the top mount, an inclined bean inlet passage is defined between the second inclined portion 32b of the hopper 32 and the tapered central portion 30 of the top mount. The inclined bean inlet passage reduces the risk of "bean popping" (popping) occurring.

[0174] Figure 3 、 Figure 4 and Figure 4a The lower tool support 20 is shown in greater detail. In addition to the axially projecting support shaft portion 18 discussed above, the lower tool support includes a lower tool support platform 36 defining a raised central boss 36a and three threaded holes 36b. The lower grinding tool 8 is supported by the support platform 36 and is secured to the lower grinding tool 8 by three screws 36c ( Figure 4 ) is fixed to the support platform.

[0175] The central portion of the platform 36 carries a bean guide element 38, which in turn defines five curved guide ribs 40. The guide ribs 40 are arranged so that when the lower mold support 20 is rotated (in a clockwise direction) by the drive shaft 10, the upper portions of the guide ribs 40 are leading edges, and the lower portions of the guide ribs 40 are swept back relative to the direction of rotation. In this way, the beans are guided or pushed radially outward from the support shaft portion 18.

[0176] In addition to guiding the beans radially outwards, the bean guiding element 38 also covers the key element 24 and prevents it from escaping from the key slots 26, 28. Therefore, the bean guiding element 38 also secures the key element 24 in place.

[0177] In addition to the bean guide element 38, the lower grinder support 20 also includes three upright, radially projecting first grinder cleaning members / sweepers 42; and a second grinder cleaning member 44 extending axially downward from the bottom surface of the lower grinder support 20 (at Figure 5 ). The second grinding cleaning member 44 includes a rearwardly swept (i.e., rearwardly relative to the direction of rotation) outwardly projecting finger-like portion 44a extending from the second grinding cleaning member 44 toward the peripheral edge portion of the lower grinding tool support 20. The projecting finger-like portion 44a generates an airflow below the lower grinding tool support 20. The generated airflow sweeps outwardly the grinding material entering the lower portion of the grinding chamber 34 (i.e., below the lower grinding tool support 20) and guides it toward an outlet 46 of the grinding chamber 34 and a discharge nozzle 48 that communicates with the grinding chamber 34 via the outlet 46.

[0178] Each first grinding cleaning member 42 includes a leading surface 50 and a trailing surface 52 , wherein the leading surface 50 is inclined backward at an angle of 20° (relative to the direction of rotation) from the radius of the lower grinder support 20 . This angle prevents bean grounds from accumulating on the leading surface 50 .

[0179] Figure 4 The lower tool support 20 is shown, wherein the lower grinding tool 8 is connected thereto by screws 36c. Figure 4 As shown, the lower grinding tool 8 includes a flat grinding surface 54 arranged perpendicular to the rotational axis defined by the drive shaft 10. Radially inwardly of the flat grinding surface, a pre-grinding portion 56 of the lower grinding tool 8 is provided. The pre-grinding portion 56 is frustoconical in shape. The lower grinding tool 8 also defines a central bore 60 in which the bean guide element 38 is disposed. Finally, the lower grinding tool 8 defines three countersunk screw holes 58 that align with the threaded holes 36b defined by the lower tool support 20. The countersunk screw holes 58 allow screws 36c to be inserted to secure the lower grinding tool 8 to the lower tool support 20 without the screw heads interfering with the grinding surface defined by the flat grinding surface 54 and the frustoconical pre-grinding portion 56.

[0180] Figure 4a The lower grinder support 20 is shown with the lower grinding grinder 8 connected thereto but without the bean guiding element. The figure shows the arrangement of the key element 24 and the two aligned keyways 26, 28.

[0181] Figure 6 and Figure 7 The top mount 16 is shown in more detail. An upper tool support 62 is secured to the downwardly facing surface of the top mount 16. The upper grinding tool 6 ( Figure 72) is connected to the downwardly facing surface of the carried upper grinding tool by screws in the same manner as the lower grinding tool 8 is fixed to the lower tool support 20.

[0182] Top mount 16 includes an annular main portion 16c connected to conical center portion 30 by three arms 16a. The gaps between adjacent arms 16a define openings 16b through which beans fall as they are transferred from hopper 32 to grinding chamber 34. Arms 16a are angled so that they form an inverted V-shape when viewed from above. Furthermore, the width of arms 16a gradually increases from conical center portion 30 toward annular main portion 16c. This V-shape of arms 16a minimizes or reduces the "pop" phenomenon, where unground or partially ground beans escape from grinding chamber 34 below top mount 16. This structure also reduces noise generated by the grinding chamber.

[0183] Screws 16d secure the top mounting member 16, the upper mold support 62, and the lower mold support 6 together.

[0184] The top mounting member further includes a positioning lug 16e projecting downwardly from the lower surface of the annular main body portion 16c. The positioning lug 16e passes through a corresponding hole defined by the upper mold support 62 and projects outwardly from the upper mold support. The positioning lug 16e is received by a corresponding groove 70 defined by the main body 4.

[0185] It will be appreciated that the upper grinding tool 6 and the lower grinding tool 8 are identical in structure and are arranged facing each other in the device so that the pre-grinding portions 56 of the two grinding tools 6, 8 face each other and together define a funnel-shaped structure that tapers towards the flat grinding surface 54 that also faces each other.

[0186] As described herein, the upper grinding tool 6 is fixed in the direction of rotation but is adjustable in the axial direction relative to the lower grinding tool 8. The adjustment mechanism is the same as that described in WO2018 / 211264. In summary, the hopper 32 is defined by a rotatable body 64, which is threadedly connected to a portion 66 of the device body 4. When the rotatable body 64 rotates relative to the device body 4, the lower portion 68 of the rotatable body moves upward or downward in a direction parallel to the axis of rotation of the drive shaft 10. The top mounting 16 is pressed against the lower portion 68 of the rotatable body 64 under the action of a spring 70a, which is arranged in a groove 70 defined by the body 4 ( Figure 2Only one groove 70 and corresponding spring 70a are shown. With the above structure, when the rotatable body 64 rotates relative to the main body 4, the lower portion 68 of the rotatable body 64 moves upward or downward, and the top mounting member 16 also moves upward or downward a corresponding distance. Because the upper tool support 62 is fixed to the top mounting member 16 and the upper grinding tool 6 is fixed to the upper tool support 62, when the rotatable body 64 rotates relative to the main body 4, the upper grinding tool moves toward or away from the lower grinding tool 8.

[0187] The grinding material from the upper grinding tool 6 and the lower grinding tool 8 is pushed radially outward and swept into the discharge port 46 by the first grinding cleaning member 42. Any grinding material that falls below the lower grinding tool support 20 is swept into the discharge port 46 by the air flow generated by the second grinding cleaning member 44. Momentum and gravity carry the grinding material from the discharge port 46 to the discharge nozzle 48.

[0188] The discharge nozzle 48 has a longitudinal axis which is angled 10° to the vertical plane in a direction opposite to the direction of the rotation axis defined by the drive shaft 10 (which itself is angled 15° to the vertical plane) so that the longitudinal axis of the discharge nozzle 48 is angled 25° to the rotation axis.

[0189] The discharge nozzle 48 defines a grind flow path from the grinding device. It should be noted that the axis of rotation and the grind flow path form an inverted V shape.

[0190] Below is an overview of the remaining features of the device 2, which are described in more detail in WO2018 / 211264.

[0191] The lower body portion 72 of the body 4 has a base 74 mounted thereunder, which projects forward to be located below the nozzle 48. The base 74 and the body 4 define an inverted figure "7" shape.

[0192] The base 74 has a two-part holder 76, 78 for a grounds collection cup 80. When the cup 80 is seated on the holder 76, 78 below the distal end of the nozzle, it can collect the grounds. The grounds collection cup 80 is described in more detail in WO2022 / 034103.

[0193] To avoid problems with static charge buildup due to abrasive material, the supports 76, 78 are made of wood, and the base 74 is provided with legs 74a, also made of wood. It has been found that by forming the supports 76, 78 and legs 74a of wood, the effects of static electricity that can cause abrasive material to stick to the device 2 or fly away are reduced or completely eliminated.

[0194] Experiments using embodiments of the invention described herein have demonstrated that 10 grams of grounds can be obtained from 10 grams of beans.

[0195] The upper body portion 82 includes a lid 84 that is pivotally mounted to the upper body portion 82 via a hinge 86 so that the lid 84 can cover the bean hopper 32 and the rotatable body 64 in the closed configuration. The lid 84 carries a magnet, and the upper body portion 82 carries a steel insert that aligns with the magnet in the closed configuration. In the closed configuration, magnetic attraction between the magnet and the steel insert latches the lid 84 in the closed configuration.

[0196] The lid 84 also includes a protruding element. In the closed configuration, the protruding element engages the plunger, which in turn is connected to a microswitch, such that in the closed configuration, the microswitch is actuated (i.e., closed), which in turn allows operation of the grinder. When the lid 84 is opened (i.e., hingedly released from its closed configuration), the protruding element disengages from the plunger, which in turn opens the microswitch. Opening the microswitch shuts off power to the motor, and the grinding device 2 is inoperable. This arrangement prevents the grinding device 2 from being operated when the lid 84 is in the open configuration.

[0197] The cover 84 is formed from a transparent polymeric material so that a user can see the amount of beans in the bean hopper 32 .

[0198] An electric motor 90 and a reduction gearbox 92 are disposed within the main body 4. The reduction gearbox 92 is configured to reduce the rotational speed of the electric motor output shaft 94 so that the drive shaft 10, which is operatively connected to the reduction gearbox 92, has a rotational speed of approximately 530 rpm. Experiments have shown that this rotational speed is suitable for operating abrasive tools in terms of grinding efficiency, noise, and vibration of the device 2.

[0199] The gears of the gearbox 92 are housed within a gearbox housing 96. The gearbox housing 96 includes a top cover 98 which in turn defines a lower bearing housing 98a extending axially upwardly from the top cover 98. The lower bearing housing 98a houses the lower bearing 12.

[0200] Figure 8 Two matching pairs of grinding tools 6a, 8a and 6b, 8b are shown. The user of the device 2 can replace the first pair of grinding tools 6a, 8a with a different second pair of grinding tools 6b, 8b. For example, Figure 8 As shown, the first pair of grinding grinds 6a, 8a can produce a finer grind than the grind produced by the second pair of grinding grinds 6b, 8b. Thus, the first pair of grinding grinds 6a, 8a can be used to prepare coffee grinds / coffee powder for, for example, an espresso machine; and the second pair of grinding grinds 6b, 8b can be used to prepare grinds for, for example, a drip coffee machine.

[0201] The process of replacing the grinding tools 6, 8 is relatively simple. The user first unscrews the rotatable body 64 from the main body 4, thereby removing the bean hopper 32 from the device 2 and allowing access to the top mount 16. The top mount, along with the upper tool support 62 and the first upper grinding tool 6a, can then be removed from the device by lifting the top mount upward. As the rotatable body 64 is removed from the main body 4, a spring 70a located in a recess 70 pushes the top mount 16 upward via the detent 16e.

[0202] After the top mount 16 is removed, the screw 18c can be unscrewed and the bean guide member 38 removed, thereby allowing the key member 24 to be removed from the key slots 26, 28. This allows the lower grinder support 20 and associated first lower grinding grinder 8a to slide axially from the drive shaft 10.

[0203] The process for installing the second pair of grinding tools 6 b, 8 b is a reverse of the above steps. Thus, the lower tool holder 20 and associated second lower grinding tool 8 b are slid axially onto the drive shaft 10. The lower tool holder is then keyed to the drive shaft 10 via the key element 24, which is held in place by the bean guide element 38. The lower tool holder is secured to the drive shaft 10 by threaded engagement of the screw 18 c with the internal thread carried by the distal end of the drive shaft 10. The top mount 16 is then positioned in place by placing the locating lugs 16 e in corresponding recesses 70 defined by the main body 4. As described above, the top mount 16 has the upper tool holder 62 and second upper grinding tool 6 b attached thereto. The top mount 16 is then secured in place by screwing the rotating body 64 onto the main body 4. This compresses the spring 70 a located within the recess 70.

[0204] With the top mount 16 coupled to the body 4 , the distal cylindrical portion 18 b and its associated sleeve 22 are rotatably disposed within a bearing 14 defined within a central portion 30 of the top mount 16 .

[0205] In use, the user opens the transparent cover 84, which stops the electric motor 90, as described above. The desired amount of beans is located in the hopper 32 and the cover 84 is closed. Closing of the cover allows the electric motor to be started.

[0206] The motor is activated, rotating the drive shaft 10 through the reduction gearbox 92. This rotation, in turn, rotates the lower grinding burrs 8. Beans fall into the grinding chamber 34 through the inclined bean inlet channel defined between the second inclined portion 32b of the hopper 32 and the conical center portion 30 of the top mounting member 16. The curved ribs 40 of the bean guide member 38 guide the beans toward the pre-grinding portions 56 of the grinding burrs 6, 8. The beans are then ground between the substantially flat grinding surfaces 54 of the grinding burrs 6, 8. The first and second grind sweepers 42, 44 then direct the bean grounds toward the discharge port 46 of the apparatus 2. The bean grounds then enter the discharge spout 48 and fall by gravity into the grounds collection cup 80.

[0207] When all beans placed in the hopper 32 have been ground, the motor can be stopped manually.

[0208] Figures 9 to 12 A second embodiment of the bean grinding device 102 of the present invention is shown. In this second embodiment, the drive shaft 10 and the axially protruding support shaft 18 of the first embodiment are replaced by a single drive shaft 110 passing through a lower grinder support 120.

[0209] like Figure 9 As shown, the upper portion 110a of the drive shaft 110 has a reduced diameter and includes a threaded portion. This allows the axially protruding main body portion 118 of the lower mold support 120 (at Figure 10 and Figure 11 1 and 2) are keyed to the drive shaft 110 via a key element 122. A lower portion of the key element 122 is positioned partially within a keyway 124 defined by the axially projecting body portion 118 of the lower mold holder 120 and partially within a corresponding keyway defined by the drive shaft 110. An upper portion of the key element 122 is positioned within a keyway defined in a cylindrical key element retaining seat 126, which is secured to the upper portion of the drive shaft 110 via a top nut 128 that engages threads carried by the upper portion 110a of the drive shaft 110.

[0210] All other features of the bean grinding device 102 are combined with the above Figures 1 to 8 The corresponding features are the same as those described above, and Figures 9 to 12 The same reference numerals are used for these features.

Claims

1. A bean grinding device comprising: main body; a pair of opposed grinding tools mounted in the body, the grinding tools comprising a non-rotating grinding tool and a rotationally driven grinding tool, the rotationally driven grinding tool having a rotation axis about which the rotationally driven grinding tool rotates; a drive motor operatively coupled to the rotationally driven abrasive tool via a drive shaft; a grind flow path defined within the body; as well as a discharge nozzle having an outlet and an inlet communicating with the grinding material flow path; wherein the non-rotating abrasive tool and the rotationally driven abrasive tool each define a respective substantially planar abrasive surface; The grinding surfaces face each other; planes defined by the grinding surfaces of the grinding tools are parallel to each other and perpendicular to the rotation axis; The proximal end of the drive shaft is connected to the drive motor via a gear box; and Deflection of the rotationally driven grinding tool about the axis of rotation is resisted on one side by a drive shaft supported in a drive shaft bearing and on the opposite side by a support shaft extending from the rotationally driven grinding tool, wherein the distal end of the support shaft is supported in a support shaft bearing assembly carried by the body.

2. The bean grinding device according to claim 1, wherein: The rotationally driven lapping tool is carried by a rotationally driven tool carrier, wherein the rotationally driven tool carrier includes a body portion defining a central passage, and the distal portion of the drive shaft is positioned within the central passage.

3. The bean grinding device according to claim 2, wherein: The support shaft extends from the main body portion of the rotationally driven grinding tool holder.

4. The bean grinding device according to any one of claims 1 to 3, wherein: The support shaft includes a main body portion and a distal end portion, and wherein the distal end portion has a diameter smaller than a diameter of the main body portion.

5. The bean grinding device according to claim 4, wherein: A distal end portion of the support shaft is rotatably received within the support shaft bearing assembly.

6. The bean grinding device according to claim 5, wherein: The distal end portion of the support shaft includes a sleeve secured thereto.

7. The bean grinding device according to any one of claims 1 to 6, wherein: The support shaft bearing assembly comprises: a central body portion defining a bore therein that rotatably receives a distal end portion of the support shaft therein; an outer retaining ring; and A plurality of connecting arms connect the central body portion to the outer retaining ring.

8. The bean grinding device according to claim 7, wherein: Each of the connecting arms is in an inverted V shape.

9. The bean grinding device according to claim 7 or 8, wherein: The apparatus further includes a bean hopper having a tapered surface and a bean guide channel surface, the tapered surface being inclined toward the central body portion of the support shaft bearing assembly, wherein the bean guide channel surface is arranged parallel to an outwardly facing surface of the central body portion; and wherein the bean guide channel surface and the outwardly facing surface of the central body portion together define a bean inlet channel, and wherein a gap between the outwardly facing surface of the central body portion and the bean guide channel surface is constant.

10. The bean grinding device according to any one of claims 1 to 9, wherein: The substantially planar grinding surface of each of the grinding tools includes grinding teeth.

11. The bean grinding device according to any one of claims 1 to 10, wherein: The non-rotating grinding tool and the rotationally driven grinding tool each have a circular cross-section, wherein the substantially flat grinding surface of each grinding tool is disposed around a peripheral edge portion of the respective grinding tool.

12. The bean grinding device according to claim 11, wherein: The non-rotating grinding tool and the rotationally driven grinding tool each include a pre-grinding portion that is provided radially inward of the grinding surface and is tapered toward the grinding surface.

13. The bean grinding device according to any one of claims 2 to 12, wherein: The rotationally driven grinder holder includes a guide portion provided radially inwardly of the rotationally driven grinding grinder, wherein the guide portion includes one or more guide ribs that guide unground beans toward the rotationally driven grinding grinder.

14. The bean grinding device according to claim 13, wherein: The guide rib is curved.

15. The bean grinding device according to claim 13 or 14, wherein: The rotationally driven tool carrier, the rotationally driven grinding tool, and the guide define a rotating grinding tool subassembly; and wherein the rotating grinding tool subassembly is keyed to the drive shaft, wherein the rotating grinding tool subassembly rotates with the drive shaft.

16. The bean grinding device according to any one of claims 1 to 15, wherein: The non-rotating grinding tool support carries the non-rotating grinding tool.

17. The bean grinding device according to claim 16, wherein: The non-rotating tool carrier is coupled to the support shaft bearing assembly; wherein the non-rotating tool carrier, the non-rotating abrasive tool, and the support shaft bearing assembly together define a fixed abrasive tool subassembly.

18. The bean grinding device according to any one of claims 1 to 17, wherein: The apparatus further includes a first article guiding element positioned below the grinding tool, wherein the first article guiding element includes one or more fingers generating an air flow to sweep the article into the article flow path.

19. The bean grinding device according to claim 18, wherein: The apparatus defines a cavity below the grinding tool, and the first grinding article guiding element is located within the cavity.

20. The bean grinding device according to any one of claims 1 to 19, wherein: The apparatus further includes a second grinding material guiding element disposed radially outwardly of the grinding tool, wherein the second grinding material guiding element includes one or more tapered protrusions that sweep the grinding material into the grinding material flow path.

21. The bean grinding device according to any one of claims 18 to 20, wherein: The first grinding material guide element and / or the second grinding material guide element are driven to rotate by the drive shaft.

22. The bean grinding device according to any one of claims 1 to 21, wherein: The apparatus further includes a non-rotating abrasive tool adjustment mechanism that adjusts an axial position of the non-rotating abrasive tool relative to the rotationally driven abrasive tool.

23. The bean grinding device according to claim 22, wherein: The non-rotating abrasive tool is carried by a non-rotating tool holder; the non-rotating tool holder includes a first threaded portion; and the apparatus includes a rotatable second threaded portion threadedly engaged with the first threaded portion, wherein rotation of the second threaded portion causes displacement of the non-rotating tool holder in an axial direction relative to the axis of rotation.

24. The bean grinding device according to any one of claims 1 to 23, wherein: The discharge nozzle defines a longitudinal axis, and the longitudinal axis of the discharge nozzle is angled relative to the rotational axis of the rotationally driven abrasive tool.

25. The bean grinding device according to claim 24, wherein: The rotation axis and the longitudinal axis of the discharge nozzle are both at an angle relative to a vertical plane.

26. The bean grinding device according to claim 25, wherein: The rotation axis and the longitudinal axis of the discharge nozzle form an inverted V shape.

27. The bean grinding device according to any one of claims 1 to 26, wherein: The device further comprises a second non-rotating grinding tool and a second rotationally driven grinding tool, wherein the first non-rotating grinding tool and the first rotationally driven grinding tool are replaceable by the second non-rotating grinding tool and the second rotationally driven grinding tool.

28. A bean grinding device comprising: main body; a pair of opposed grinding tools mounted in the body, the grinding tools comprising a non-rotating grinding tool and a rotationally driven grinding tool, the rotationally driven grinding tool having a rotation axis about which the rotationally driven grinding tool rotates; a drive motor operatively coupled to the rotationally driven abrasive tool via a drive shaft; a grind flow path defined within the body; as well as a discharge nozzle having an outlet and an inlet in communication with the abrasive flow path, wherein the non-rotating abrasive tool and the rotationally driven abrasive tool each define a respective substantially planar abrasive surface; The grinding surfaces face each other; planes defined by the grinding surfaces of the grinding tools are parallel to each other and perpendicular to the rotation axis; The proximal end of the drive shaft is connected to the drive motor via a gear box; and The device defines a drive shaft upper bearing assembly in which the distal end of the drive shaft is rotationally supported and a lower bearing in which the proximal portion of the drive shaft is rotationally supported, wherein the lower bearing is in the form of a cylindrical sleeve retained within the housing.

29. The bean grinding device according to claim 28, wherein: The rotationally driven lapping tool is carried by a rotationally driven tool holder, wherein the tool holder includes a body portion defining a central channel, and an intermediate portion of the drive shaft is positioned within the central channel such that a distal portion of the drive shaft extends from a first end of the central channel and a proximal portion of the drive shaft extends from a second end of the central channel.

30. The bean grinding device according to claim 29, wherein: The distal portion of the drive shaft includes a body portion and a distal end portion, and wherein the distal end portion has a diameter that is smaller than a diameter of the body portion.

31. The bean grinding device according to claim 30, wherein: The distal end portion of the drive shaft is rotatably received within the drive shaft upper bearing assembly.

32. The bean grinding device according to any one of claims 28 to 31, wherein The bearing assembly on the drive shaft includes: a central body portion defining a bore therein for receiving the distal end of the drive shaft; an outer retaining ring; and A plurality of connecting arms connect the central body portion to the outer retaining ring.

33. The bean grinding device according to claim 32, wherein: Each of the connecting arms is in an inverted V shape.

34. The bean grinding device according to claim 32 or 33, wherein: The apparatus further includes a bean hopper having a tapered surface and a bean guide channel surface, the tapered surface being inclined toward the central body portion of the drive shaft upper bearing assembly, wherein the bean guide channel surface is arranged parallel to an outwardly facing surface of the central body portion; and wherein the bean guide channel surface and the outwardly facing surface of the central body portion together define a bean inlet channel, and wherein a gap between the outwardly facing surface of the central body portion and the bean guide channel surface is constant.

35. The bean grinding device according to any one of claims 28 to 34, wherein A rotationally driven grinder carrier carries the rotationally driven grinding grinder; wherein the rotationally driven grinder carrier includes a guide portion arranged radially inwardly of the rotationally driven grinding grinder, wherein the guide portion includes one or more guide ribs that guide unground beans toward the rotationally driven grinding grinder.

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