Rotor structure and inner cylinder structure of sand mill

Abstract

The invention discloses a rotor structure and an inner cylinder structure of a sand mill. A plurality of grinding blocks and first bulges are arranged on the outer wall surface of the rotor structure; the grinding blocks and the first protrusions are arranged on the outer wall face of the rotor structure in a crossed mode in the circumferential direction and the axial direction of the rotor structure. Each grinding block is provided with four side faces and a top face, the first side face faces the first end of the grinding cavity, the second side face faces the second end of the grinding cavity, and the third side face is a slope face and obliquely faces the grinding block axially adjacent to the grinding block. In the grinding blocks distributed on the outer wall face of the rotor structure in the axial direction, the normal directions of the third side faces of at least one pair of adjacent grinding blocks intersect, and the intersection point is located between the pair of adjacent grinding blocks; a plurality of oval third protrusions are arranged on the inner wall face of the inner cylinder structure. According to the sand mill, the collision frequency between grinding media and between the grinding media and the wall face of the inner cylinder can be increased, the uniformity degree of materials in the grinding cavity is improved, and the grinding and smashing efficiency of the sand mill is improved.

Description

Technical Field

[0001] The invention relates to the technical field of sand mills, and in particular to a rotor structure and an inner cylinder structure of a sand mill. Background Art

[0002] A sand mill is a machine that achieves grinding by driving the material and grinding media in the grinding chamber to collide and rub against each other through a rotor. Due to the different specific gravities and hardnesses of the material and the grinding media, the material will be ground and decomposed into tiny particles during the collision between the material and the grinding media. Prior art 201821867936.4 discloses a grinding rotor and a sand mill, and designs a disc-type grinding rotor. The geometric structural features of the protrusions on both sides are used to promote the collision between the material and the grinding media, wherein the first protrusion and the second protrusion can increase the face area (contact area) of the turntable and the material and the grinding media, so that more material and the grinding media can obtain speed and promote collision, and the second protrusion also gives the material and the grinding media centrifugal force to avoid accumulation at the bottom. However, this structural feature is concentrated in the circumferential direction, and the ability to give speed to the material and the grinding media in other spaces is limited, so that the grinding effect of the rotor is not high. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a rotor structure and an inner cylinder structure of a sand mill, which can increase the collision frequency and enable materials and grinding media to participate in the collision crushing process more effectively.

[0004] In order to solve the above technical problems, the present invention discloses a rotor structure of a sand mill in a first aspect, wherein the main body of the rotor structure is a rotatable cylindrical structure, and a plurality of grinding blocks are arranged on the outer wall surface of the rotor structure, and the rotor structure is installed in a grinding chamber of the horizontal sand mill, and the grinding chamber is a cylindrical structure with two ends; the discharge port of the horizontal sand mill is connected to the grinding chamber through the first end of the grinding chamber, and the feed port of the horizontal sand mill is connected to the grinding chamber through the second end of the grinding chamber;

[0005] A first protrusion is also provided on the outer wall surface of the rotor structure;

[0006] The grinding block and the first protrusion are cross-arranged on the outer wall surface of the rotor structure along the circumferential direction and the axial direction of the rotor structure, so that the grinding block is adjacent to the first protrusion in both the circumferential direction and the axial direction of the rotor structure, and the first protrusion is adjacent to the grinding block in both the circumferential direction and the axial direction of the rotor structure;

[0007] The grinding block has four side surfaces and a top surface, wherein the first side surface faces the first end of the grinding chamber, the second side surface faces the second end of the grinding chamber, and the third side surface is a slope surface and is obliquely opposite to the grinding block axially adjacent to the grinding block;

[0008] Among the grinding blocks distributed along the axial direction on the outer wall surface of the rotor structure, the normal directions of the third side surfaces of at least one pair of adjacent grinding blocks intersect with each other, and the intersection point is located between the pair of adjacent grinding blocks.

[0009] As an optional embodiment, in the first aspect of the present invention, the first protrusion is a pair of elongated protrusions, and the orientation of the pair of elongated protrusions has a first angle, the projection of the angular bisector of the first angle on the outer wall surface of the rotor structure is in the same direction as the circumferential direction of the rotor structure on the outer wall surface, and the tip of the first angle points to the third side surface of the grinding block circumferentially adjacent to the first protrusion; the first angle is 60 to 150 degrees.

[0010] As another optional embodiment, in the first aspect of the present invention, the first angle is 90 degrees.

[0011] As another optional embodiment, in the first aspect of the present invention, the slope of the third side surface is 20 to 70 degrees, and the slope is based on the tangential direction of the junction between the outer wall surface of the rotor structure and the third side surface.

[0012] As another optional embodiment, in the first aspect of the present invention, among the grinding blocks distributed axially on the outer wall surface of the rotor structure, the normal direction of the third side surface of the grinding block near the discharge port intersects with the normal direction of the third side surface of the grinding block near the feed port and the intersection point is located between the two grinding blocks.

[0013] As another optional embodiment, in the first aspect of the present invention, the straight line projection of any straight line across the width direction on the third side surface on the normal plane at the intersection of the third side surface and the outer wall surface of the rotor, the projection of the straight line on the outer wall surface of the rotor structure and the projection of the central axis of the rotor structure on the outer wall surface include an angle of 15 to 75 degrees.

[0014] As another optional embodiment, in the first aspect of the present invention, the grinding block is provided with an elliptical second protrusion on the first side surface and the second side surface; the orientation of the second protrusion has a second angle with the radial direction of the rotor, and the second angle is 15 to 75 degrees, or the orientation of the second protrusion is in the same direction as the radial direction of the rotor.

[0015] The second aspect of the present invention discloses an inner cylinder structure of a sand mill, wherein the grinding chamber of the inner cylinder structure is the grinding chamber described in the first aspect of the present invention; a plurality of elliptical third protrusions are provided on the inner wall surface of the inner cylinder structure; the orientation of each of the third protrusions on the inner wall of the inner cylinder structure has a third angle with the axial direction of the inner cylinder structure, and the third angle is 20 to 70 degrees.

[0016] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0017] In the embodiment of the present invention, the third side surface of the grinding block is tilted outward and forms a certain angle with the axial direction of the rotor structure, so that the speed of the grinding medium after being accelerated by the grinding block can obtain components in the radial direction and the axial direction. By retracting the third side surfaces of adjacent grinding blocks inward, the materials and grinding media near the third side surfaces of the two groups of grinding blocks can be moved in the designed direction to achieve directional collision, thereby greatly improving the collision frequency, accelerating the circulation rate of the grinding media in the grinding chamber, and reducing the accumulation dead zone of the grinding media on both sides of the material inlet and outlet of the grinding chamber, thereby achieving better grinding effect; the first protrusion on the rotor structure can disturb objects in the surrounding area, avoid the material and the grinding medium from sticking to the outer wall of the rotor structure without participating in the collision movement, achieve the effect of dispersion and empowerment, and improve the uniformity of materials of various particle sizes in the grinding chamber, thereby improving the concentration of the particle size distribution of the material at the discharge port. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 It is a structural schematic diagram of a rotor structure of a sand mill disclosed in an embodiment of the present invention;

[0020] Figure 2 The embodiment of the present invention is disclosed Figure 1 A partial enlarged schematic diagram of part A;

[0021] Figure 3 It is a schematic diagram of the rotor structure and grinding chamber structure of a sand mill disclosed in an embodiment of the present invention;

[0022] Figure 4 The embodiment of the present invention is disclosed Figure 3 Schematic diagram of the flow direction of materials and grinding media when the middle rotor structure rotates counterclockwise;

[0023] Figure 5 is another structural schematic diagram of a rotor structure of a sand mill disclosed in an embodiment of the present invention;

[0024] Figure 6 The embodiment of the present invention is disclosed Figure 5 Schematic diagram of the force direction of the second protrusion when the middle rotor structure rotates counterclockwise;

[0025] Figure 7It is another structural schematic diagram of a rotor structure of a sand mill disclosed in an embodiment of the present invention;

[0026] Figure 8 Schematic diagram of radial cross-section structure of a rotor structure of a sand mill disclosed in an embodiment of the present invention

[0027] Fig. 9 It is a structural schematic diagram of an inner cylinder structure of a sand mill disclosed in an embodiment of the present invention;

[0028] Fig.10 is another structural schematic diagram of an inner barrel structure of a sand mill disclosed in an embodiment of the present invention;

[0029] Fig.11 It is another structural schematic diagram of the inner barrel structure of a sand mill disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Embodiment 1

[0032] See also Figures 1 to 8 The embodiment of the present invention discloses a rotor structure 1 of a horizontal sand mill, wherein the main body of the rotor structure 1 is a rotatable cylindrical structure, and a plurality of grinding blocks 11 are arranged on the outer wall surface of the rotor structure 1. The rotor structure 1 is arranged in a grinding chamber 2 of the horizontal sand mill, and the grinding chamber 2 is a cylindrical structure with two ends; the discharge port B of the horizontal sand mill is connected to the grinding chamber 2 through the first end 21 of the grinding chamber 2, and the feed port C of the horizontal sand mill is connected to the grinding chamber 2 through the second end 22 of the grinding chamber 2; wherein:

[0033] The outer wall surface of the rotor structure 1 is also provided with a first protrusion 12;

[0034] The grinding blocks 11 and the first protrusions 12 are cross-arranged on the outer wall surface of the rotor structure 1 along the circumferential direction and the axial direction of the rotor structure 1, so that the grinding blocks 11 are adjacent to the first protrusions 12 in both the circumferential direction and the axial direction of the rotor structure 1, and the first protrusions 12 are adjacent to the grinding blocks 11 in both the circumferential direction and the axial direction of the rotor structure 1;

[0035] The grinding block 11 has four side surfaces and a top surface, wherein the first side surface 111 faces the first end 21 of the grinding chamber 2, the second side surface 112 faces the second end 22 of the grinding chamber 2, and the third side surface 113 is a slope surface and is obliquely opposite to the grinding block 11 axially adjacent to the grinding block 11;

[0036] Among the grinding blocks 11 distributed along the axial direction on the outer wall surface of the rotor structure 1 , the normal directions of the third side surfaces 113 of at least one pair of adjacent grinding blocks 11 intersect with each other, and the intersection point is located between the pair of adjacent grinding blocks 11 .

[0037] Optionally, the fourth side surface can also be configured in the same manner as the third side surface 113, that is, a sloped surface and diagonally opposite to the grinding block 11 axially adjacent to the grinding block 11, so that the rotor structure 1 can rotate forward or reverse. If only the third side surface 113 is configured in this manner, the rotation direction of the rotor structure 1 must make the third side surface 113 face forward.

[0038] See also Figure 1 , 3 The feed port C of the horizontal sand mill of this embodiment is arranged between the inner wall of the grinding chamber 2 and the outer wall of the rotor structure 1, so that the material first enters the outer wall of the rotor structure 1 for grinding and then exits from the discharge port B at the other end of the grinding chamber 2. The rotor structure 1 may be provided with a through hole 14 away from the feed port C, so that the material and the grinding medium (such as zirconium balls) enter the rotor structure 1 from the outer wall for further grinding. The flow channel is a blank area on the rotor where the grinding block 11 is not arranged, and the flow area is large, and the flow resistance of the material passing through the grinding block area is relatively low; the grinding blocks 11 are staggered, and the path of the material and the grinding medium is tortuous when they move along the axial direction of the rotor, which can also increase the grinding time of the material.

[0039] See also Figure 3 , Figure 3 It is marked with the force direction of the third side surface 113 when the rotor rotates counterclockwise. It can be seen that when the third side surfaces 113 at both ends are oriented inward (so that the materials and grinding media near the material inlet and outlet at both ends move toward the middle, increasing the collision frequency), the directions of the adjacent third side surfaces 113 in the middle are different, and all point to the grinding blocks 11 adjacent in the oblique direction, among which the second and third grinding blocks are oriented inward, and the third grinding block and the grinding block near the feed port C are oriented inward, which can make the materials and grinding media near the third side surfaces 113 of the two groups of grinding blocks move in the pointed direction to achieve directional collision, thereby greatly increasing the collision frequency.

[0040] When the material and the grinding medium flow through the first protrusion 12, a vortex will appear, and a vortex will be formed during separation, which can disturb the material in the surrounding area, and can prevent the material and the grinding medium from sticking to the outer wall of the rotor without participating in the collision movement, thereby achieving a dispersion and energizing effect, improving the uniformity of the material in the grinding area, and thus improving the grinding and capturing frequency of materials of different particle sizes during grinding. At the same time, the disturbed material and the grinding medium just hit the third side surface 113 of the grinding block 3 in the direction of movement. The third side surface 113 can push the material and the grinding medium to a larger surrounding area according to its direction to further increase the collision frequency.

[0041] It can be seen that in the embodiment of the present invention, the third side surface 113 of the grinding block 11 is tilted outward and forms a certain angle with the axial direction of the rotor structure 1, so that the speed of the grinding medium after being accelerated by the grinding block can obtain components in the radial direction and the axial direction. By the third side surfaces 113 of adjacent grinding blocks being retracted inward, the materials and grinding media near the third side surfaces 113 of the two groups of grinding blocks can be moved in the designed direction to achieve directional collision, thereby greatly improving the collision frequency, accelerating the circulation rate of the grinding media in the grinding chamber, and reducing the accumulation dead zone of the grinding media on both sides of the material inlet and outlet of the grinding chamber, thereby achieving a better grinding effect; the first protrusion 12 on the rotor structure 1 can disturb objects in the surrounding area, avoid the material and the grinding medium from sticking to the outer wall of the rotor structure 1 without participating in the collision movement, achieve the effect of dispersion and empowerment, and improve the uniformity of materials of various particle sizes in the grinding chamber 2, thereby improving the concentration of the particle size distribution of the material at the discharge port.

[0042] Optionally, the grinding block 11 and the rotor structure 1 of the present embodiment can be connected by bolts and made of different materials to achieve detachability, low manufacturing difficulty and easy replacement after wear.

[0043] In an optional embodiment, the first protrusion 12 is a pair of elongated protrusions, and the orientation of the pair of elongated protrusions has a first angle, the projection of the angular bisector of the first angle on the outer wall surface of the rotor structure 1 is in the same direction as the circumferential direction of the rotor structure 1 on the outer wall surface, and the tip of the first angle points to the third side surface 113 of the grinding block 11 adjacent to the first protrusion 12; the first angle is 60 to 150 degrees.

[0044] In this embodiment, see Figures 3-4When the material and the grinding medium pass through the first protrusion 12, a jet phenomenon will be formed, which can quickly increase the movement speed of the material and the grinding medium in the flow layer area on the outer wall of the rotor 1 and increase the intensity of the collision. At the same time, the accelerated material and the grinding medium just meet the third side surface 113 of the grinding block 3 in the direction of movement. The third side surface 113 can directionally push the material and the grinding medium with a higher flow rate to the surrounding area according to its direction, further empowering the material and the grinding medium, increasing the intensity of the collision in the surrounding area and the uniformity of the material, and shortening the circulation period of the grinding medium.

[0045] In yet another optional embodiment, the first angle is 90 degrees.

[0046] In yet another optional embodiment, the slope of the third side surface 113 is 20 to 70 degrees, and the slope is based on the tangential direction of the junction between the outer wall surface of the rotor structure 1 and the third side surface 113 .

[0047] In another optional embodiment, among the grinding blocks 11 distributed axially on the outer wall surface of the rotor structure 1, the normal direction of the third side surface 113 of the grinding block 11 close to the discharge port B intersects with the normal direction of the third side surface 113 of the grinding block 11 close to the feed port C, and the intersection point is located between the two grinding blocks 11.

[0048] In another optional embodiment, a straight line projection of an arbitrary straight line on the third side surface across the width direction on a normal plane at the junction of the third side surface and the outer wall surface of the rotor has an angle of 15 to 75 degrees between the projection of the straight line on the outer wall surface of the rotor structure and the projection of the central axis of the rotor structure on the outer wall surface.

[0049] In yet another alternative embodiment, see Figures 5-6 The grinding block 11 is provided with an elliptical second protrusion 13 on both the first side surface 111 and the second side surface 112 . The second protrusion 13 is oriented at a second angle with the radial direction of the rotor, and the second angle is 15 to 75 degrees.

[0050] See also Figures 5-6 , Figure 6is the force direction of the second protrusion 13 when the rotor 1 rotates counterclockwise. In this embodiment, the extrusion collision empowering surface is mainly the front surface of the grinding block 11, and the elliptical second protrusion 13 is auxiliary, and the friction shear empowering surface is mainly the side surface of the grinding block 11, and the second protrusion 13 is auxiliary. On the one hand, the elliptical second protrusion 13 increases the area of ​​the friction shear empowering surface and the extrusion collision empowering surface. On the other hand, through the oblique arrangement, part of the grinding media is given a centrifugal movement trend when it contacts it. In addition, due to the different empowering paths, there is a relatively obvious speed difference between it and the grinding media on the outside of the grinding block 11, which is manifested as the difference in physical quantities such as speed scalar, speed direction and rotation angular velocity, thereby increasing the collision frequency of the grinding media in the grinding area between the outside of the grinding block 11 and the inner wall of the grinding chamber 2.

[0051] In yet another optional embodiment, the second angle is 45 degrees.

[0052] In yet another alternative embodiment, see Figure 7 The grinding block 11 is provided with an elliptical second protrusion 13 on both the first side surface 111 and the second side surface 112 , and the direction of the second protrusion 13 is the same as the radial direction of the rotor.

[0053] In yet another optional embodiment, a plurality of through holes 14 are provided on the surface of the rotor structure 1 , and the through holes 14 are away from the second end 22 of the grinding chamber 2 .

[0054] See also Figure 8 In another optional embodiment, the projections of the inner wall surfaces of the through hole 14 on both sides of the rotor structure 1 in the axial direction on the radial section of the rotor structure 1 are two straight lines 141 and 142, and the angles 143 and 144 between the two straight lines and the radial direction on the radial section of the rotor structure 1 are 0 to 45 degrees and 0 to 45 degrees, respectively.

[0055] In another optional embodiment, the central angle between each grinding block 11 and the axially adjacent grinding block 11 is 22.5 to 60 degrees; wherein the central angle takes the projection of the central axis of the rotor structure 1 on the radial section of the rotor structure 1 as the center of the circle, and connects the projection points of the center of gravity of the two grinding blocks 11 on the radial section of the rotor structure 1 respectively.

[0056] Embodiment 2

[0057] See also Figures 9-11The embodiment of the present invention discloses an inner cylinder structure 3 of a horizontal sand mill, wherein the grinding chamber of the inner cylinder structure 3 is the grinding chamber 2 described in the first embodiment; a plurality of elliptical third protrusions 31 are provided on the inner wall surface of the inner cylinder structure 3; the direction of each of the third protrusions 31 on the inner wall of the inner cylinder structure 3 forms a third angle with the axial direction of the inner cylinder structure 3, and the third angle is 15 to 75 degrees.

[0058] In this embodiment, a plurality of elliptical third protrusions 31 are provided on the inner wall surface of the inner cylinder structure 3. The third protrusions 31 are facing each other at a certain angle with the axial direction of the rotor structure 1 and the adjacent third protrusions 31 are facing in opposite directions, so that the speed of the grinding medium after contacting the cylinder body obtains axial and radial components, thereby reducing the speed synergy of the grinding medium between the outer side of the grinding block 11 and the inner wall of the inner cylinder structure 3, improving the speed difference between the grinding media, and thus increasing the collision frequency; the angles of the third protrusions 31 at both ends are facing inward, so that the grinding media at both ends can move toward the middle to accelerate its circulation in the cylinder.

[0059] In an optional embodiment, there is a fourth angle between the orientations of each pair of adjacent third protrusions 31 on the inner wall of the inner tube structure 3, and the angle between the bisector of the fourth angle corresponding to at least one pair of adjacent third protrusions 31 and the circumferential tangent of the inner tube structure 3 is less than 10 degrees.

[0060] In another optional embodiment, there is a fifth angle between the orientation of the third protrusion 31 near the feed port C and the orientation of the third protrusion 31 near the discharge port B, and the angle between the bisector of the fifth angle and the circumferential tangent of the inner cylinder structure 3 is less than 10 degrees, so that two adjacent protrusions are at least not parallel, reducing the speed synergy between the grinding media.

[0061] In yet another optional embodiment, the third protrusions 31 form a plurality of circumferential circles on the inner wall of the inner cylinder structure 3 that intersect perpendicularly with the axial direction of the inner cylinder structure 3 .

[0062] In another optional embodiment, the third protrusions 31 are equidistant in the circumferential direction of the inner wall of the inner cylinder structure 3 and the third angle is arranged alternately in positive and negative directions. In another optional embodiment, the third protrusions 31 correspond to the grinding blocks 11, wherein the projection of each grinding block 11 on the inner wall of the inner cylinder structure 3 at a certain moment coincides with the installation position of the third protrusion 31 corresponding to the grinding block. When designing, it is best for the third protrusion 31 to be located directly above the grinding block 11, because the acceleration effect at the directly above position is better than that in the interval area, and the protrusion dispersion effect is better.

[0063] The contents disclosed in the embodiments of the present invention only disclose the preferred embodiments of the present invention, which are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, it should be understood by those skilled in the art that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A rotor structure of a sand mill, wherein the main body of the rotor structure is a rotatable cylindrical structure, and a plurality of grinding blocks are arranged on the outer wall surface of the rotor structure, and the rotor structure is installed in the grinding chamber of the horizontal sand mill, and the grinding chamber is a cylindrical structure with two ends; the discharge port of the horizontal sand mill is connected to the grinding chamber through the first end of the grinding chamber, and the feed port of the horizontal sand mill is connected to the grinding chamber through the second end of the grinding chamber; characterized in that A first protrusion is also provided on the outer wall surface of the rotor structure; The grinding block and the first protrusion are cross-arranged on the outer wall surface of the rotor structure along the circumferential direction and the axial direction of the rotor structure, so that the grinding block is adjacent to the first protrusion in both the circumferential direction and the axial direction of the rotor structure, and the first protrusion is adjacent to the grinding block in both the circumferential direction and the axial direction of the rotor structure; The grinding block has four side surfaces and a top surface, wherein the first side surface faces the first end of the grinding chamber, the second side surface faces the second end of the grinding chamber, and the third side surface is a slope surface and is obliquely opposite to the grinding block axially adjacent to the grinding block; Among the grinding blocks distributed along the axial direction on the outer wall surface of the rotor structure, the normal directions of the third side surfaces of at least one pair of adjacent grinding blocks intersect with each other, and the intersection point is located between the pair of adjacent grinding blocks.

2. The rotor structure according to claim 1, characterized in that: The first protrusion is a pair of long strip-shaped protrusions, and the orientation of the pair of long strip-shaped protrusions has a first angle. The projection of the angular bisector of the first angle on the outer wall surface of the rotor structure is in the same direction as the circumferential direction of the rotor structure on the outer wall surface, and the tip of the first angle points to the third side surface of the grinding block circumferentially adjacent to the first protrusion; the first angle is 60 to 150 degrees.

3. The rotor structure according to claim 2, characterized in that: The first angle is 90 degrees.

4. The rotor structure according to claim 1, characterized in that: The slope of the third side surface is 20 to 70 degrees, and the slope is based on the tangential direction of the junction between the outer wall surface of the rotor structure and the third side surface.

5. The rotor structure according to claim 1, characterized in that: Among the grinding blocks distributed axially on the outer wall surface of the rotor structure, the normal direction of the third side surface of the grinding block close to the discharge port intersects with the normal direction of the third side surface of the grinding block close to the feed port, and the intersection point is located between the two grinding blocks.

6. The rotor structure according to claim 1, characterized in that: An arbitrary straight line on the third side surface that crosses the width direction is projected on the normal plane at the junction of the third side surface and the outer wall surface of the rotor, and an angle between the projection of the straight line on the outer wall surface of the rotor structure and the projection of the central axis of the rotor structure on the outer wall surface is 15 to 75 degrees.

7. The rotor structure according to claim 1, characterized in that: The grinding block is provided with an elliptical second protrusion on the first side surface and the second side surface; the second protrusion is oriented at a second angle with the radial direction of the rotor, and the second angle is 15 to 75 degrees, or the second protrusion is oriented in the same direction as the radial direction of the rotor.

8. The rotor structure according to claim 7, characterized in that: The second angle is 45 degrees.

9. An inner cylinder structure of a sand mill, characterized in that: The grinding chamber of the inner cylinder structure is the grinding chamber according to any one of claims 1 to 8; A plurality of elliptical third protrusions are arranged on the inner wall surface of the inner cylinder structure; the orientation of each of the third protrusions on the inner wall of the inner cylinder structure forms a third angle with the axial direction of the inner cylinder structure, and the third angle is 20 to 70 degrees.

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