Grinding structure and coffee grinder

Abstract

The application discloses a grinding structure and a bean grinder, which comprises a grinding support extending in the front-rear direction and provided with a grinding cavity in the middle part, a movable cutter and a fixed cutter arranged in the grinding cavity; an adjusting support arranged on the front side of the grinding support and capable of moving forward and backward relative to the grinding support through an adjusting assembly, the adjusting support being provided with a hollow inner cavity penetrating in the front-rear direction; and a fixed cutter support detachably arranged in the hollow inner cavity, the rear end surface of the fixed cutter support being fixedly connected with the fixed cutter, the fixed cutter extending into the grinding cavity and located on the front side of the movable cutter, and the rear end surface of the fixed cutter and the front end surface of the movable cutter forming a grinding gap. When the cutter needs to be cleaned, the fixed cutter support and the fixed cutter thereon are only needed to be detached from the adjusting support, the adjusting support remains stationary during the detaching process, and after cleaning, the fixed cutter support is only needed to be reinstalled into the adjusting support to fix, so that the original axial positioning relationship can be restored.

Description

Technical Field

[0001] This invention relates to the field of coffee grinder technology, and more particularly to a grinding structure and a coffee grinder. Background Technology

[0002] A coffee grinder is used to grind coffee beans into a uniform powder to maximize the release of flavor compounds during brewing. Horizontal coffee grinders typically rely on a pair of opposing rotating metal blades to crush the beans into powder through compression and shearing forces, while precisely controlling the grind coarseness by adjusting the tiny gap between the blades.

[0003] Chinese invention patent application No. 202610082404.2 discloses a coffee grinder that supports convenient disassembly and adjustment, including a main body. A control panel is hinged to the first end of the main body. When the control panel is opened, an adjustment component covering the end of the main body is exposed. The adjustment component is connected to a grinding component located inside the main body. The adjustment component and the grinding component can be disassembled from the main body sequentially or together. When the adjustment component is installed in the main body, it is driven by an adjustment motor inside the main body to adjust the grinding coarseness of the grinding component. The control panel, through a movable connection, enables a maintenance door panel that can be opened at any time to expose the adjustment component and the grinding component, allowing the user to remove them as needed for quick cleaning.

[0004] Most horizontal coffee grinders on the market, as described in the aforementioned patent, place the grind size adjustment mechanism at the very front of the machine. This makes cleaning the burr discs significantly inconvenient. The reason is that disassembly and cleaning require removing the adjustment ring first. After removing the burr discs, ordinary users need to recalibrate the zero point position, which is difficult to accurately restore to the original zero position. When reassembling, even a slight increase in force applied by the fingers can cause the starting position of the threaded engagement to shift, preventing a return to the original grind size and thus affecting the coffee's taste and flavor that the user is accustomed to. Summary of the Invention

[0005] The first technical problem to be solved by the present invention is to propose a grinding structure that does not require zero-point calibration after disassembling and assembling the tool disc, in light of the above-mentioned technical status quo.

[0006] The second technical problem to be solved by the present invention is to provide a coffee grinder with the above-mentioned grinding structure in view of the current state of the technology.

[0007] The technical solution adopted by the present invention to solve the first technical problem mentioned above is: a grinding structure, comprising... A grinding support extends in the front-to-back direction and has a grinding cavity in the middle, wherein a moving cutter disc and a fixed cutter disc are arranged in the grinding cavity; Its characteristic is that it also includes An adjusting bracket is disposed on the front side of the grinding bracket. The adjusting bracket can move back and forth relative to the grinding bracket via an adjusting component. The adjusting bracket has a hollow inner cavity extending through the front and rear direction. A fixed cutter head support is detachably disposed in the hollow inner cavity. The fixed cutter head is fixedly connected to the rear end face of the fixed cutter head support. The fixed cutter head extends into the grinding cavity and is located in front of the moving cutter head. A grinding gap is formed between the rear end face of the fixed cutter head and the front end face of the moving cutter head.

[0008] Compared with the prior art, the advantages of this invention are as follows: the fixed cutter head support is detachably disposed in the hollow inner cavity of the adjusting support, and the fixed cutter head is fixedly connected to the rear end face of the fixed cutter head support and extends into the grinding chamber. Therefore, when the cutter head needs to be cleaned, the fixed cutter head support along with the fixed cutter head on it can be removed from the adjusting support, exposing both the moving and fixed cutter heads simultaneously for thorough cleaning. Throughout the disassembly process, the adjusting support and its adjusting components used to adjust the grinding gap remain stationary and are not disassembled. Therefore, after cleaning, the fixed cutter head support can be reinstalled back into the hollow inner cavity and fixed to the adjusting support to restore the original axial positioning relationship. The front and rear positions of the adjusting support remain unchanged, and the initial setting of the grinding gap after reinstallation is exactly the same as before disassembly, eliminating the need for cumbersome readjustment. This simplifies the maintenance process and ensures the consistency of grinding accuracy.

[0009] To ensure smooth rotation of the moving cutter disc, preferably, the grinding chamber is provided with a moving cutter disc support, the moving cutter disc support has a rotating shaft extending in the front-back direction, and the moving cutter disc is fixedly sleeved on the rotating shaft; the grinding structure also includes a grinding motor, the output shaft of the grinding motor being drivenly connected to the rotating shaft.

[0010] Preferably, the adjustment assembly includes a push-pull rod extending in a front-to-back direction. The front end of the push-pull rod is fixedly connected to the adjustment bracket, and the rear end of the push-pull rod is driven to move in the front-to-back direction. By using a rear-end driven push-pull rod to control the front adjustment bracket, an adjustment assembly located in the middle section can replace the commonly available front-end adjustment assemblies.

[0011] Preferably, the adjustment assembly further includes a limiting bracket fixedly disposed at the rear end of the grinding bracket; a first adjusting ring sleeved on the main body of the grinding motor and fixed relative to the rear end of the push-pull rod, the first adjusting ring being movably disposed within the limiting bracket in the front-to-back direction; and a second adjusting ring sleeved on the outside of the first adjusting ring, the second adjusting ring being threadedly engaged with the first adjusting ring, the second adjusting ring driving the first adjusting ring to move in the front-to-back direction when rotating, thereby driving the push-pull rod to move back and forth. The rotational motion of the second adjusting ring is converted into precise axial displacement of the first adjusting ring through the threaded engagement, and with the guidance and positioning of the limiting bracket, fine adjustment and self-locking retention of the grinding gap are achieved.

[0012] To improve adjustment accuracy and ease of operation, the adjustment assembly preferably includes an adjustment motor and a gear transmission mechanism, with the output shaft of the adjustment motor driving the second adjustment ring to rotate via the gear transmission mechanism. Alternatively, the electric adjustment can be replaced with manual adjustment by eliminating the adjustment motor and replacing the gear transmission mechanism with a dial, which expands the design possibilities for the appearance.

[0013] Specifically, the gear transmission mechanism includes a first gear and a second gear. The first gear is sleeved on the main body of the grinding motor. The first gear is fixedly connected to the second adjusting ring, and when the first gear rotates, it drives the second adjusting ring to rotate synchronously. The second gear meshes with the first gear, and the output shaft of the adjusting motor drives the second gear to rotate.

[0014] To provide precise positional feedback on the size of the grinding gap, preferably, a grating ring is also fitted around the main body of the grinding motor. The grating ring is located behind the first gear and is fixedly connected to the first gear and rotates synchronously with the first gear. An optical coupler bracket is installed on the limiting bracket, extending rearward to the rear of the grating ring. An optical coupler is installed near the rear end of the optical coupler bracket. The optical coupler has a U-shaped structure, with its opening facing forward, and the two U-shaped sides of the optical coupler are located on the inner and outer sides of the grating ring along the tangential direction, respectively.

[0015] To facilitate the addition of soybeans, preferably, the adjusting bracket has a first feeding channel, the fixed blade bracket has a second feeding channel that communicates with the first feeding channel, and the fixed blade bracket has a third feeding channel at the axial position of the fixed blade bracket. The front end of the third feeding channel communicates with the second feeding channel, and the rear end communicates with the grinding chamber.

[0016] To achieve rapid and accurate positioning of the fixed tool disc bracket for subsequent installation, preferably, the adjusting bracket is embedded with at least two first positioning magnets, which are spaced apart circumferentially; the fixed tool disc bracket extends with multiple first ears, which are located on the front side of the adjusting bracket, and each first ear is embedded with a second positioning magnet, which are arranged in pairs with the first positioning magnets.

[0017] The technical solution adopted by the present invention to solve the second technical problem mentioned above is: a coffee grinder, characterized in that it has the grinding structure described in any one of the above-mentioned items. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the grinding structure according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the grinding structure from another angle according to an embodiment of the present invention; Figure 3 This is a cross-sectional view of the grinding structure along the central axis according to an embodiment of the present invention; Figure 4 This is a cross-sectional view of the grinding structure of this invention at a position deviating from the central axis when the grinding gap is at its minimum. Figure 5 This is a cross-sectional view of the grinding structure in an embodiment of the present invention when the grinding gap is at its maximum. Figure 6 This is a schematic diagram of the grinding structure of the present invention when the fixed blade holder is disassembled; Figure 7 This is a schematic diagram of the fixed tool disc support and the fixed tool disc being disassembled according to an embodiment of the present invention. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0020] like Figures 1 to 7 The image shows a preferred embodiment of a grinding structure and a coffee grinder according to the present invention.

[0021] The coffee grinder of this embodiment includes a grinding structure and a collecting structure. The collecting structure is located below the grinding structure and is used to collect the ground material powder.

[0022] Grinding structure such as Figure 1 and Figure 3 As shown, the whole extends in the front-to-back direction. Its core structure is the grinding support 1. The grinding support 1 is hollowly formed in the axial direction with a grinding cavity 11. The grinding cavity 11 is provided with a moving cutter 2 and a fixed cutter 3. The grinding gap between the two is adjustable.

[0023] The front side of the grinding support 1 is provided with an adjustment support 4. The adjustment support 4 can move back and forth relative to the grinding support 1. The adjustment support 4 has a hollow inner cavity that runs through the front and back direction, which is used to detachably install the fixed tool disc support 6.

[0024] A grinding motor 5 is provided on the rear side of the grinding support 1 to provide rotational power for the movable cutter disc 2. A movable cutter disc support 7 is provided inside the grinding cavity 11. The movable cutter disc support 7 has a rotating shaft 71 extending in the front-back direction. The movable cutter disc 2 is fixedly sleeved on the rotating shaft 71 and rotates with the rotating shaft 71.

[0025] The main body of the grinding motor 5 is located at the rear end of the grinding bracket 1. Its output shaft passes forward through the rear wall of the grinding bracket 1 and extends into the grinding cavity 11, and is fixedly installed inside the movable cutter disc bracket 7. The output shaft and the rotating shaft 71 are coaxially arranged. When the grinding motor 5 rotates, the output shaft drives the movable cutter disc bracket 7 and the movable cutter disc 2 to rotate synchronously.

[0026] A fixed cutter head bracket 6 is detachably installed in the hollow inner cavity of the adjusting bracket 4. A fixed cutter head 3 is fixedly connected to the rear end face of the fixed cutter head bracket 6. Specifically, as follows: Figure 7 As shown, the rear end face of the fixed cutter head bracket 6 has an annular groove 61, and the fixed cutter head 3 is embedded in the annular groove 61 and fastened to the fixed cutter head bracket 6 by at least two screws. When the fixed cutter head bracket 6 is installed into the adjusting bracket 4, the fixed cutter head 3 extends rearward into the grinding chamber 11 and is located in front of the moving cutter head 2. The aforementioned grinding gap is formed between the rear end face of the fixed cutter head 3 and the front end face of the moving cutter head 2, as shown. Figure 4 and Figure 5 As shown, the size of the grinding gap depends on the relative front-to-back position of the fixed cutter head 3 and the moving cutter head 2.

[0027] The adjusting bracket 4 can move back and forth via the adjusting assembly, thereby driving the fixed blade disc 3 and the fixed blade disc support 6 to move as a whole, changing the grinding gap. The core of the adjusting assembly is a push-pull rod 81 extending in the front-back direction. The grinding bracket 1 has a first through hole 12 extending in the front-back direction, and the adjusting bracket 4 has a second through hole 41 directly opposite the first through hole 12, which also extends through the adjusting bracket 4 in the front-back direction. The push-pull rod 81 passes through the first through hole 12, and its front end continues forward through the second through hole 41 and extends out of the front end face of the adjusting bracket 4. A rod head sleeve 82 is fixed to the front end of the push-pull rod 81 extending out of the adjusting bracket 4. The outer diameter of the rod head sleeve 82 is larger than the inner diameter of the second through hole 41, and the rear end face of the rod head sleeve 82 abuts against the front end face of the adjusting bracket 4. Thus, when the push-pull rod 81 moves forward, the adjusting bracket 4 can be pulled forward through the rod head sleeve 82. The diameter of the push-pull rod 81 is reduced at the rod head to form a first stepped surface, while the inner wall of the second through hole 41 is provided with a corresponding second stepped surface. When the push-pull rod 81 moves backward, the first stepped surface and the second stepped surface abut against each other, thereby pushing the adjusting bracket 4 backward.

[0028] The grinding motor 5 is fitted with a limiting bracket 83 and a first adjusting ring 84, both located at the rear end of the grinding bracket 1. The limiting bracket 83 is fixedly installed with the grinding bracket 1 and has a circumferential surface and an annular surface extending radially inward from the rear end of the circumferential surface. The first adjusting ring 84 only has a circumferential surface. The limiting bracket 83 is fitted onto the outside of the first adjusting ring 84, and the limiting bracket 83, the first adjusting ring 84, and the rear end face of the grinding bracket 1 together form an annular cavity. Figure 4 and Figure 5 As shown, the rear end of the push-pull rod 81 passes backward through the grinding bracket 1 and enters the annular cavity.

[0029] The first adjusting ring 84 has a mounting ear 841 that protrudes radially outward on its circumferential surface. The mounting ear 841 has a mounting hole. The rear end of the push-pull rod 81 passes through the mounting hole and is fixed relative to the first adjusting ring 84, so that the push-pull rod 81 and the first adjusting ring 84 move together in the front-back direction.

[0030] like Figure 3 As shown, the rear end of the first adjusting ring 84 extends rearward and protrudes beyond the rear end face of the limiting bracket 83. This protruding portion has an external thread, and a second adjusting ring 85 is fitted onto this external thread. The second adjusting ring 85 has a matching internal thread. When the second adjusting ring 85 is turned, because the push-pull rod 81 restricts the rotational freedom of the first adjusting ring 84, the first adjusting ring 84 can only slide back and forth and cannot rotate. Furthermore, the second adjusting ring 85 is axially limited and can only rotate, not move back and forth. Therefore, rotating the second adjusting ring 85 will force the first adjusting ring 84 to move in the back-and-forth direction, thereby driving the push-pull rod 81 to move back and forth through the mounting lug 841. In addition, a spring 811 is fitted onto the push-pull rod 81. This spring 811 always provides a rearward force to the push-pull rod 81 to eliminate thread clearance and ensure the stability of the adjustment.

[0031] To achieve automatic adjustment, a first gear 86 is also fitted onto the main body of the grinding motor 5. This first gear 86 is fixedly connected to the second adjusting ring 85, and its rotation drives the second adjusting ring 85 to rotate synchronously. The adjustment assembly also includes an adjusting motor 87 and a second gear 88. The output shaft of the adjusting motor 87 drives the second gear 88 to rotate, and the second gear 88 meshes with the first gear 86. The adjusting motor 87 is fixedly installed on the limiting bracket 83 and is located below the grinding motor 5 and behind the limiting bracket 83. When the adjusting motor 87 operates, power is transmitted to the second adjusting ring 85 through the second gear 88 and the first gear 86, which electrically drives the first adjusting ring 84 and the push-pull rod 81 to move.

[0032] To precisely control the grinding gap, a grating ring 91 is also fitted around the main body of the grinding motor 5 in this embodiment, such as... Figure 2As shown, the grating ring 91 is located behind the first gear 86 and is fixedly connected to the first gear 86, rotating synchronously with the first gear 86. Since the rotation angle of the second adjusting ring 85 is linearly related to the displacement of the first adjusting ring 84, the rotation angle of the grating ring 91 can reflect the position of the push-pull rod 81, that is, the size of the grinding gap.

[0033] An optocoupler bracket 92 is fixedly installed on the limiting bracket 83, such as Figure 2 As shown, the optocoupler bracket 92 extends rearward to the rear of the grating ring 91. An optocoupler 93 is installed near the rear end. The optocoupler 93 has a U-shaped structure with its opening facing forward. The two U-shaped sides of the optocoupler 93 are located on the inner and outer sides of the grating ring 91 along the tangential direction, respectively. The edge of the grating ring 91 extends into the U-shaped groove of the optocoupler 93. The grating ring 91 has transparent and opaque gratings distributed circumferentially. By detecting the pulse signal generated by the change in light transmission when the grating ring 91 rotates, the optocoupler 93 can accurately calculate the rotation angle of the grating ring 91, thereby indirectly obtaining the real-time size of the grinding gap and providing feedback for closed-loop control.

[0034] The upper part of the adjusting bracket 4 has a first feeding channel 42 extending tangentially, and the upper part of the fixed blade bracket 6 has a second feeding channel 62 corresponding to the first feeding channel 42. This second feeding channel 62 also extends tangentially. Figure 3 As shown. After the fixed blade holder 6 is installed into the adjusting bracket 4, the first feed channel 42 and the second feed channel 62 are connected. A third feed channel 63 extending axially is also provided at the axis position of the fixed blade holder 6. The front end of the third feed channel 63 is connected to the lower end of the second feed channel 62, and the rear end of the third feed channel 63 is connected to the grinding chamber 11. The material enters the grinding chamber 11 sequentially through the first feed channel 42, the second feed channel 62, and then along the axial third feed channel 63.

[0035] The adjusting bracket 4 and the fixed cutter head bracket 6 are detachably connected and equipped with a positioning mechanism and a fastening mechanism. The adjusting bracket 4 has at least two first positioning magnets 43 embedded within it, such as... Figure 3 As shown, these first positioning magnets 43 are distributed circumferentially at intervals. The fixed tool disc support 6 extends tangentially with multiple first ears 64, which are located on the front side of the adjusting support 4. Each first ear 64 is embedded with a second positioning magnet 65. The second positioning magnets 65 and the first positioning magnets 43 are arranged in pairs corresponding to each other, achieving rapid alignment through magnetic attraction. The adjusting support 4 and the fixed tool disc support 6 are also respectively provided with corresponding screw holes. The screw holes of the fixed tool disc support 6 are opened on the second ears 66, which are also located on the front side of the adjusting support 4. The screw holes are used to insert quick-release screws 67, detachably fixing the adjusting support 4 and the fixed tool disc support 6 to ensure no relative displacement between them during operation.

[0036] The grinding support 1 has an opening at its lower part, and a vertically downward-extending powder outlet channel 13 is connected to the outside of the opening. An electrostatic silicone sheet is provided at the upper end of the powder outlet channel 13 to eliminate static electricity generated during the grinding process.

[0037] The working principle of adjusting the grinding gap in this embodiment is as follows: The control system energizes the adjusting motor 87, whose output shaft drives the second gear 88 to rotate. The rotation of the second gear 88 causes the first gear 86 and the second adjusting ring 85 to rotate synchronously. Since the first adjusting ring 84 can only slide in the back-and-forth direction, when the second adjusting ring 85 rotates, the thread forces the first adjusting ring 84 to move in the back-and-forth direction. The back-and-forth movement of the first adjusting ring 84 directly drives the push-pull rod 81 to move synchronously back and forth. The adjusting bracket 4 follows the push-pull rod 81 in moving synchronously back and forth, and the fixed blade holder 6 and the fixed blade 3 fixed thereon move back and forth accordingly, thereby increasing or decreasing the grinding gap.

[0038] The working principle of disassembling and installing the fixed cutter head bracket 6 in this embodiment is as follows: like Figure 6 As shown, ensure that the grinding motor 5 and the adjusting motor 87 are completely stopped, and unscrew all quick-release screws 67. At this point, the rigid mechanical connection between the fixed blade holder 6 and the adjusting bracket 4 is released. After the screws are released, the suction force still holds the fixed blade holder 6 within the adjusting bracket 4. The operator only needs to hold the fixed blade holder 6 by hand and apply force in the forward direction to overcome the magnetic attraction, and the fixed blade holder 6, along with the fixed blade 3 attached to it, can be pulled forward as a whole, detaching from the hollow inner cavity of the adjusting bracket 4. At this time, the fixed blade 3 is completely withdrawn from the grinding chamber 11, and the moving blade 2 is exposed, while the rear end face of the fixed blade 3 is also fully exposed. Figure 7 As shown, the fixed cutter head 3 can be removed from the fixed cutter head bracket 6, allowing the operator to easily wipe or brush the surfaces of the fixed cutter head 3 and the moving cutter head 2, as well as the inside of the grinding chamber 11.

[0039] After confirming that the fixed cutter head 3, moving cutter head 2, and grinding chamber 11 are clean and dry, and that the fixed cutter head 3 has been reinstalled in the fixed cutter head bracket 6, the operator holds the fixed cutter head bracket 6 and aligns it with the hollow inner cavity inlet at the front end of the adjusting bracket 4, then slowly pushes it in backward. When the bracket reaches a certain depth, the first positioning magnet 43 and the second positioning magnet 65 gradually approach each other, and the magnetic attraction begins to take effect, guiding the fixed cutter head bracket 6 to automatically center and slide backward until the magnets are fully attracted. At this point, the fixed cutter head bracket 6 reaches its axial pre-position, and its second feed channel 62 automatically aligns with the first feed channel 42 on the adjusting bracket 4. Because the circumferential arrangement of the magnets is unique, the design ensures that the attraction is maximum only when the angle is correct. Continue to push gently backward, ensuring that the rear end face of the fixed cutter head bracket 6 enters the grinding chamber 11 to the preset initial position. At this point, the magnetic attraction has firmly attached the fixed cutter head bracket 6 to the adjusting bracket 4. Pass the quick-release screw 67 through the screw hole of the adjusting bracket 4 and the screw hole of the second ear 66 of the fixed cutter head bracket 6, and tighten it. After locking, the initial gap between the fixed cutter head 3 and the moving cutter head 2 is restored to its state before disassembly. Since the adjusting bracket 4 itself has not moved, there is no need to readjust the initial position.

Claims

1. A grinding structure, comprising The grinding support (1) extends in the front-to-back direction and has a grinding cavity (11) formed in the middle. The grinding cavity (11) is provided with a moving cutter disc (2) and a fixed cutter disc (3). Its features are, Also includes An adjusting bracket (4) is disposed on the front side of the grinding bracket (1). The adjusting bracket (4) can move back and forth relative to the grinding bracket (1) through an adjusting component. The adjusting bracket (4) has a hollow inner cavity that extends through the front and back direction. A fixed blade support (6) is detachably disposed in the hollow inner cavity. The fixed blade (3) is fixedly connected to the rear end face of the fixed blade support (6). The fixed blade (3) extends into the grinding cavity (11) and is located in front of the moving blade (2). A grinding gap is formed between the rear end face of the fixed blade (3) and the front end face of the moving blade (2).

2. The grinding structure according to claim 1, characterized in that, The grinding chamber (11) is provided with a movable cutter head support (7), which has a rotating shaft (71) extending in the front-back direction. The movable cutter head (2) is fixedly sleeved on the rotating shaft (71). The grinding structure also includes a grinding motor (5), whose output shaft is connected to the rotating shaft (71) in a transmission manner.

3. The grinding structure according to claim 2, characterized in that, The adjustment assembly includes a push-pull rod (81) extending in the front-back direction. The front end of the push-pull rod (81) is fixedly connected to the adjustment bracket (4). The rear end of the push-pull rod (81) is driven to move in the front-back direction.

4. The grinding structure according to claim 3, characterized in that, The adjustment component also includes A limiting bracket (83) is fixedly disposed at the rear end of the grinding bracket (1); The first adjusting ring (84) is sleeved on the main body of the grinding motor (5) and fixed relative to the rear end of the push-pull rod (81). The first adjusting ring (84) is movable in the front-back direction and is set in the limiting bracket (83). The second adjusting ring (85) is sleeved outside the first adjusting ring (84). The second adjusting ring (85) is threadedly engaged with the first adjusting ring (84). When the second adjusting ring (85) rotates, it drives the first adjusting ring (84) to move in the front-back direction, thereby driving the push-pull rod (81) to move back and forth.

5. The grinding structure according to claim 4, characterized in that, The adjustment assembly also includes an adjustment motor (87) and a gear transmission mechanism, wherein the output shaft of the adjustment motor (87) drives the second adjustment ring (85) to rotate through the gear transmission mechanism.

6. The grinding structure according to claim 5, characterized in that, The gear transmission mechanism includes a first gear (86) and a second gear (88). The first gear (86) is sleeved on the main body of the grinding motor (5). The first gear (86) is fixedly connected to the second adjusting ring (85), and the first gear (86) drives the second adjusting ring (85) to rotate synchronously when it rotates. The second gear (88) meshes with the first gear (86), and the output shaft of the adjusting motor (87) drives the second gear (88) to rotate.

7. The grinding structure according to claim 6, characterized in that, The grinding motor (5) is also fitted with a grating ring (91) on its main body. The grating ring (91) is located behind the first gear (86), and the grating ring (91) is fixedly connected to the first gear (86) and rotates synchronously with the first gear (86). An optical coupler bracket (92) is mounted on the limiting bracket (83), and the optical coupler bracket (92) extends rearward to the rear of the grating ring (91); The optical coupler bracket (92) has an optical coupler (93) installed near the rear end. The optical coupler (93) has a U-shaped structure, with the opening of the optical coupler (93) facing forward. The two U-shaped sides of the optical coupler (93) are located on the inner and outer sides of the grating ring (91) along the tangential direction.

8. The grinding structure according to claim 1, characterized in that, The adjusting bracket (4) has a first feeding channel (42), the fixed blade bracket (6) has a second feeding channel (62) that communicates with the first feeding channel (42), and the fixed blade bracket (6) also has a third feeding channel (63) at the axial position of the fixed blade bracket (6). The front end of the third feeding channel (63) communicates with the second feeding channel (62), and the rear end communicates with the grinding chamber (11).

9. The grinding structure according to claim 1, characterized in that, The adjusting bracket (4) is embedded with at least two first positioning magnets (43), which are spaced apart circumferentially; the fixed blade bracket (6) extends with a plurality of first ears (64), which are located on the front side of the adjusting bracket (4), and each first ear (64) is embedded with a second positioning magnet (65), which is arranged in pairs with the first positioning magnets (43).

10. A coffee grinder, characterized in that, It has a grinding structure as described in any one of claims 1 to 9.

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