Wear resistance testing device and testing method for rotating blades

Abstract

The present invention relates to the field of tool testing technology, and discloses a wear resistance testing device and a testing method for a rotating blade, wherein the device comprises a piece to be tested and a base, wherein the piece to be tested is a rotating cutter head, and the top of the base is provided with a sound insulation test cover, and the top of the sound insulation test cover is provided with an upper test assembly, and the upper test assembly comprises a sealing disk, a driving assembly, a cutter head mounting seat and a flat sweeping frame, wherein the cutter head mounting seat is mounted on the bottom outer wall of the sealing disk, the driving end of the driving assembly is connected to a linkage shaft, the linkage shaft is inserted into the cutter head mounting seat, and the flat sweeping frame is horizontally slidably connected to the inner wall of the sealing disk. The present invention changes the input frequency of the test basin to form a non-periodic vibration, performs an instantaneous impact on the rotating cutter head, observes the height or distribution pattern of the test particles thrown up, evaluates the impact load generated by the rotating cutter head under different conditions, and intuitively tests the service life of the rotating cutter head under a continuous impact load while removing the fluid effect.

Description

Technical Field

[0001] The present invention relates to the field of tool testing, and more particularly to a wear resistance testing device and a testing method for a rotating blade. Background Art

[0002] Rotating blades are used to crush beans or other hard ingredients in equipment such as soymilk machines and wall breakers, but their service life is related to many factors.

[0003] Especially at the initial startup or when the blade encounters larger beans or other hard components, a momentary impact load will be generated. These suddenly applied forces will cause high pressure stress on the blade, which may cause the blade to become blunt or cause tiny cracks.

[0004] When the blade becomes blunt or has tiny cracks, the crushing effect will be poor during subsequent operations, and beans or other hard ingredients will be stuck in the rotating cutter head, causing the driving motor of the rotating cutter head to overload, overheat and be damaged, affecting the use of equipment such as soy milk machines and wall breakers. Summary of the Invention

[0005] The present invention provides a wear resistance testing device and a testing method for a rotating blade, which solve the technical problems in the related art.

[0006] The present invention provides a wear resistance testing device for a rotating blade, comprising:

[0007] The test piece is a rotary cutter head, comprising a blade holder, a first blade, and a second blade. The blade holder is connected to a connecting shaft, and the first blade and the second blade are sequentially superimposed and mounted on the connecting shaft.

[0008] The base is provided with a sound insulation test cover on the top of the base, and an upper test assembly is installed on the top of the sound insulation test cover. The upper test assembly includes a sealing disk, a driving assembly, a cutter head mounting seat and a flat sweeping frame. The cutter head mounting seat is mounted on the outer wall of the bottom end of the sealing disk. The driving end of the driving assembly is connected to a linkage shaft, which is inserted into the cutter head mounting seat. The flat sweeping frame is horizontally slidably connected to the inner wall of the sealing disk. One end of the flat sweeping frame is connected to the linkage shaft, and the blade holder of the test piece is mounted on the bottom end of the linkage shaft.

[0009] There are ring-shaped leakage holes in the sealing disk, and the hole diameter is between 0.5cm and 1.2cm;

[0010] During the test, the test particles are placed in the sealed disk and swept horizontally by the sweeping frame to move the test particles of different sizes into the corresponding leak holes. The test particles leak out of the leak holes and continuously impact the test piece from above.

[0011] The lower test piece is installed in the base. The lower test piece includes a rotatable lifting seat, a sliding ring and a test basin body. The sliding ring is clamped on the outer edge of the top end of the test basin body. The sliding ring is slidably connected to the inner wall of the sound insulation test cover. The movable end of the rotatable lifting seat is installed on the bottom outer wall of the test basin body. The test basin body includes a vibration basin and a vibration source. The vibration basin is a bucket structure and is fixed on the top outer wall by a sealing ring to make the vibration basin in the test basin body tensioned. The vibration end of the vibration source is connected to the bottom outer wall of the vibration basin.

[0012] Furthermore, an annular guide disk is provided on the outer side wall of the sound insulation test cover close to the cutter head mounting seat. When the test particles are emitted downward for testing, they are guided to the outer side wall of the test piece through the guide disk.

[0013] Furthermore, it also includes a planetary assembly, which is sleeved on the linkage shaft and includes a driving gear, a gear ring and a driven gear. An insertion shaft extends from the end of the sweeping frame, and the insertion shaft is inserted into the driven gear. The end of the sweeping frame is always connected to the inner wall of the sealing disk. When the driving motor drives the linkage shaft to rotate, it also drives the driving gear to rotate. The driven gear makes a circular motion between the gear ring and the driving gear, and the sweeping frame connected thereto sweeps horizontally inside the sealing disk.

[0014] Furthermore, a groove is provided on the outer edge of the sliding ring, and a vertical convex strip is provided on the inner side wall of the sound insulation test cover, and the groove is clamped on the outer wall of the convex strip.

[0015] Furthermore, the test particles are placed in a test basin, and the signal end of the test basin is connected to an audio controller. The audio controller inputs signals of different frequencies into the test basin to make the test basin move and drive the test particles to jump.

[0016] Furthermore, the driving assembly includes a driving motor and a reducer, the output shaft of the driving motor is connected to the reducer, the reducer is installed on the output shaft of the driving motor, and the output shaft of the reducer is connected to the linkage shaft.

[0017] Furthermore, a connecting thread is provided at the shaft end of the linkage shaft, and a plurality of limiting protrusions are distributed on the outer wall of the linkage shaft near the connecting thread. When the test piece is installed on the linkage shaft, the opening groove at the bottom end of the blade holder is clamped on the outer wall of the limiting protrusion.

[0018] Furthermore, a balance bearing is provided inside the flat sweeping frame. When the piece to be tested is mounted on the bottom end of the linkage shaft, the blade holder is inserted into the balance bearing.

[0019] Furthermore, the test piece includes a blade holder, a first blade and a second blade. The blade holder is connected to a connecting shaft. The first blade and the second blade are superimposed and installed on the connecting shaft in sequence. The shaft end of the connecting shaft is locked by a locking bolt, and a support washer is provided at the connection between the first blade and the second blade.

[0020] The present invention also provides a method for testing the wear resistance of a rotating blade, which is performed using the aforementioned wear resistance testing device for a rotating blade, comprising the following steps:

[0021] S100, preparation before testing: install the test piece on the linkage shaft, place the test particles into the vibration basin and sealing disk of the test basin, and install the sound insulation test cover on the base;

[0022] S200, pre-test image acquisition: Before the test, images are acquired from the top, left, right, front, and back views of the test piece, with the acquisition positions covering the blade and the edge of the test piece;

[0023] S300, Test Item 1: During the test, the drive assembly rotates the linkage shaft and the test piece on it. Simultaneously, the linkage shaft drives the sweeping frame to rotate within the sealing disk, sweeping the test particles within the sealing disk into the leak hole and impacting the test piece.

[0024] S400, Test Item 2: Based on step S300, a signal is input to the test basin. Different frequency signals are input to achieve different heights of test particle jumping. The blade face and blade edge of the test piece are tested separately or simultaneously.

[0025] S500, result comparison: Set a set of test cycles for the above two test items. After the test, take photos of the test piece at a position consistent with the initial photo acquisition position, and compare the photos with the initial photo acquisition to observe whether there is any obvious damage on the blade and the blade surface.

[0026] The beneficial effects of the present invention are:

[0027] In order to simulate the behavior of beans or hard materials under the impact of a rotating cutter head, the present invention uses a test basin to drive test particles. This is an indirect test method used to study the impact of vibration on particulate matter. By changing the input frequency of the test basin, non-periodic vibration is generated, which instantaneously impacts the rotating cutter head. By observing the height or distribution pattern of the thrown test particles, the impact load generated by the rotating cutter head under different conditions is evaluated. By removing the fluid effect in the actual environment, the service life of the rotating cutter head under continuous impact load is intuitively tested. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a front view of a wear resistance testing device for a rotating blade according to the present invention;

[0029] Figure 2 This is a test effect diagram of a wear resistance testing device for a rotating blade of the present invention;

[0030] Figure 3 This is a schematic diagram of the connection structure between a test assembly, a drive assembly and a test piece of a wear resistance testing device for a rotating blade according to the present invention;

[0031] Figure 4 The present invention Figure 3 Schematic diagram of the connection structure between the linkage shaft and the test piece;

[0032] Figure 5 The present invention Figure 1 Schematic diagram of the structure of the test basin;

[0033] Figure 6 The present invention Figure 1 Assembly drawing of the test piece;

[0034] Figure 7 The present invention provides a relationship table between input frequency and height of test particles thrown up in a wear resistance test device for a rotating blade.

[0035] In the figure: 100, base; 110, rotatable lifting seat; 200, test basin; 210, sliding ring; 220, vibration basin; 230, convex strip; 240, vibration source; 300, sound insulation test cover; 310, guide plate; 400, upper test assembly; 410, cutter head mounting seat; 420, protective cover; 430, sealing plate; 440, linkage shaft; 441, limiting protrusion; 450, leak hole; 460, flat sweeping frame; 470, gear ring; 480, driven gear; 490, driving gear; 500, driving assembly; 510, driving motor; 520, reducer; 600, test particles; 700, piece to be tested; 710, blade holder; 720, first blade; 730, supporting washer; 740, second blade; 750, locking bolt. DETAILED DESCRIPTION

[0036] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed solely to enable those skilled in the art to better understand and implement the subject matter described herein, and that the functions and arrangements of the elements discussed may be varied without departing from the scope of this specification. Various examples may omit, substitute, or add various processes or components as needed. In addition, features described with respect to some examples may also be combined in other examples.

[0037] like Figures 1-6As shown, a wear resistance testing device for a rotating blade includes a test piece 700, which is a rotating cutter head. The rotating cutter head can be the main rotating crushing component of a device such as a soy milk maker or a wall breaker. The test piece 700 includes a blade holder 710, a first blade 720, and a second blade 740. The blade holder 710 is connected to a connecting shaft. The first blade 720 and the second blade 740 are sequentially superimposed and mounted on the connecting shaft. The shaft end of the connecting shaft is locked by a locking bolt 750. A support washer 730 is provided at the connection between the first blade 720 and the second blade 740.

[0038] In one embodiment of the present invention, Figure 6 As shown, the first blade 720 is bent downward at both ends, and both sides of both ends are blades, and the second blade 740 is a cross-shaped structure, with blades on all four sides of the second blade 740, and the blade part is bent upward;

[0039] The base 100 is provided with a soundproof test cover 300 on the top of the base 100. The upper test assembly 400 is installed on the top of the soundproof test cover 300. The upper test assembly includes a sealing disk 430, a drive assembly 500, a tool head mounting seat 410 and a flat sweeping frame 460. The tool head mounting seat 410 is mounted on the bottom outer wall of the sealing disk 430.

[0040] In one embodiment of the present invention, an annular guide plate 310 is provided on the outer wall of the soundproof test cover 300 near the tool head mounting seat 410. When the test particles 600 are emitted downward for testing, they are guided by the guide plate 310 to the outer wall of the test piece 700.

[0041] The drive assembly 500 includes a drive motor 510 and a reducer 520. The output shaft of the drive motor 510 is connected to the reducer 520, and the reducer 520 is installed to the output shaft of the drive motor 510. The output shaft of the reducer 520 is connected to the linkage shaft 440. The linkage shaft 440 is inserted into the cutter head mounting seat 410. A planetary assembly is sleeved on the linkage shaft 440, including a driving gear 490, a gear ring 470 and a driven gear 480. An insertion shaft extends from the end of the sweeping frame 460, and the insertion shaft is inserted into the driven gear 480. The end of the sweeping frame 460 always abuts against the inner wall of the sealing disk 430. When the drive motor 510 drives the linkage shaft 440 to rotate, it also drives the driving gear 490 to rotate. The driven gear 480 performs a circular motion between the gear ring 470 and the drive gear 490, and the sweeping frame 460 connected thereto sweeps horizontally in the sealing disk 430.

[0042] In one embodiment of the present invention, a connecting thread is provided at the shaft end of the linkage shaft 440, and a plurality of limiting protrusions 441 are distributed on the outer wall of the linkage shaft 440 near the connecting thread. When the test piece 700 is mounted on the linkage shaft 440, the open groove at the bottom end of the blade holder 710 is clamped on the outer wall of the limiting protrusion 441.

[0043] A balance bearing is provided inside the flat sweeping frame 460. When the test piece 700 is mounted on the bottom end of the linkage shaft 440, the blade holder 710 is inserted into the balance bearing.

[0044] The sealing disk 430 is provided with an annularly distributed leakage hole 450, and the aperture size of the leakage hole 450 is between 0.5cm and 1.2cm;

[0045] In one embodiment of the present invention, a protective cover 420 is provided on the top of the sealing cover, and an axis-through hole is provided on the top outer wall of the protective cover 420;

[0046] That is, during the test process, test particles 600 are placed in the sealing disk 430 and swept horizontally by the sweeping frame 460 inside the sealing disk 430 to sweep the test particles 600 of different sizes into the corresponding leak holes 450. The test particles 600 leak out of the leak holes 450 and continuously impact the test piece 700 from above.

[0047] The lower test piece is installed in the base 100 and includes a rotatable lifting seat 110, a sliding ring 210, and a test basin 200. The sliding ring 210 is clamped on the outer edge of the top of the test basin 200 and is slidably connected to the inner wall of the sound insulation test cover 300. The movable end of the rotatable lifting seat 110 is installed on the outer wall of the bottom end of the test basin 200.

[0048] In one embodiment of the present invention, a groove is provided on the outer edge of the sliding ring 210, and a vertical ridge 230 is provided on the inner side wall of the sound insulation test cover 300, and the groove is clamped on the outer wall of the ridge 230;

[0049] The test basin 200 includes a vibration basin 220 and a vibration source 240. The vibration basin 220 is made of leather and has a bucket-shaped structure. A sealing ring is fixed on the outer edge of the top end of the vibration basin 220 to keep the vibration basin 220 in tension within the test basin 200. The vibration end of the vibration source 240 is connected to the outer wall of the bottom end of the vibration basin 220.

[0050] The test particles 600 are placed in the test basin 200. The signal end of the test basin 200 is connected to an audio controller. The audio controller inputs signal segments of different frequencies into the test basin 200, causing the test basin 200 to drive the test particles 600 to jump.

[0051] The beating of the test particle 600 is related to the input frequency signal segment. When the input frequency increases, the beating height of the test particle 600 becomes higher. Similarly, when the input frequency decreases, the beating height of the test particle 600 becomes lower.

[0052] In one embodiment of the present invention, the test particles 600 may impact the blade face and the edge of a rotating blade.

[0053] The present invention also provides a method for testing the wear resistance of a rotating blade, comprising the following steps:

[0054] Install the test piece 700 onto the linkage shaft 440 , place the test particles 600 into the vibration basin 220 and the sealing disk 430 of the test basin 200 , and install the soundproof test cover 300 onto the base 100 ;

[0055] The test piece 700 is mounted on the linkage shaft 440 through a threaded connection. The notch of the blade holder 710 is locked on the limiting protrusion 441, and the blade holder 710 is stably inserted into the blade mounting seat 410.

[0056] At the same time, before testing, the bottom (looking up) and four sides of the test piece 700 are photographed (the best is the left, right, front and back views) to ensure that the blade and edge of the test piece 700 are fully covered;

[0057] Test Item 1: Power on and conduct the test. During the test, the drive assembly 500 rotates the linkage shaft 440 and the test piece 700 thereon. Simultaneously, the linkage shaft 440 drives the sweeping frame 460 to rotate within the sealing disk 430, sweeping the test particles 600 within the sealing disk 430 into the leak hole 450 and impacting the test piece 700.

[0058] During testing, the drive motor 510 rotates the linkage shaft 440, which in turn drives the drive gear 490. The driven gear 480 rotates between the gear ring 470 and the drive gear 490, and simultaneously drives the horizontal sweeping frame 460 to sweep horizontally, causing the test particles 600 to fall through the leak hole 450. The test particles 600 are then guided by the guide plate 310 to the outer wall of the test piece 700.

[0059] Test Item 2: Based on Test Item 1, a signal is input to the test basin 200. Different frequency signals are input to cause the test particles 600 to bounce at different heights. This allows for separate testing of the blade face and edge of the test piece 700, as well as simultaneous testing of both.

[0060] During the test, the initial height of the rotatable lift base 110 can be adjusted, and the rotatable lift base 110 can be used to drive the test particle 600 to perform a combined motion of rotation and upward jumping;

[0061] The adjustment is performed by rotating the lifting seat 110 to drive the test basin 200 and the sliding ring 210 to slide along the inner wall of the sound insulation test cover 300;

[0062] The test basin 200 rotates in the sliding ring 210 during the rotation process. The test basin 200 can perform a combined motion of rotation and vibration.

[0063] Set a test cycle for the two test items above (e.g., 5 minutes per cycle). After the test, take photos of the bottom and four sides of the test piece 700 (the sampling positions remain the same as the initial sampling positions) and compare them with the initial sampling photos to observe whether there is any obvious damage on the blade and blade surface.

[0064] In one embodiment of the present invention, the test particle 600 is a uniform spherical particle with a diameter of about 5-12 mm (similar to the size of a soybean) and a density of.

[0065] The vibration of the test basin 200 can be approximated as simple harmonic motion. In each cycle, the maximum displacement (vibration height) of the test basin 200 is known. When the test particle 600 contacts the surface of the test basin 200, it is a completely elastic collision, that is, the energy loss is negligible.

[0066] The relationship expression is as follows:

[0067] Where: is the maximum height to which the test particle 600 is thrown, is the maximum displacement (vibration height) of the test basin 200, where is the angular frequency, is the input frequency, and is the acceleration due to gravity, which is approximately 9.81 m / s 2 .

[0068] like Figure 7 As shown in the table, the table shows the influence of the maximum displacement (vibration height) at different input frequencies on the maximum height of the test particle 600 thrown, assuming A=1mm. As the frequency increases, the height of the particle thrown increases significantly. However, in reality, when the frequency is very high, due to other physical limitations (such as air resistance, inelastic collisions, etc.), the actual result may not increase as shown in the table, but it can already meet the test requirements.

[0069] The above describes the embodiments of this embodiment, but this embodiment is not limited to the above specific implementation methods. The above specific implementation methods are merely illustrative and not restrictive. Ordinary technicians in this field can also make many forms based on the inspiration of this embodiment, all of which are protected by this embodiment.

Claims

1. A wear resistance testing device for a rotating blade, characterized in that: include: The test piece (700) is a rotating blade head, comprising a blade holder (710), a first blade (720), and a second blade (740). The blade holder (710) is connected to a connecting shaft, and the first blade (720) and the second blade (740) are sequentially stacked and mounted on the connecting shaft. A base (100), the top of the base (100) is provided with a sound insulation test cover (300), the top of the sound insulation test cover (300) is installed with an upper test assembly (400), the upper test assembly includes a sealing disk (430), a driving assembly (500), a cutter head mounting seat (410) and a flat sweeping frame (460), the cutter head mounting seat (410) is installed on the bottom outer wall of the sealing disk (430), the driving end of the driving assembly (500) is connected to a linkage shaft (440), the linkage shaft (440) is inserted in the cutter head mounting seat (410), the flat sweeping frame (460) is horizontally slidably connected to the inner wall of the sealing disk (430), one end of the flat sweeping frame (460) is connected to the linkage shaft (440), and the blade holder (710) of the test piece (700) is installed on the bottom end of the linkage shaft (440); Leakage holes (450) are provided in an annular arrangement in the sealing disk (430), and the aperture of the leakage holes (450) is between 0.5 cm and 1.2 cm. During the test, the test particles (600) are placed in the sealing disk (430), and the test particles (600) of different sizes are swept into the corresponding leak holes (450) by the flat sweeping frame (460). The test particles (600) leak out of the leak holes (450) and continuously impact the test piece (700) from above. The lower test piece is installed in the base (100), and the lower test piece includes a rotatable lifting seat (110), a sliding ring (210) and a test basin (200). The sliding ring (210) is clamped on the outer edge of the top end of the test basin (200), and the sliding ring (210) is slidably connected to the inner wall of the sound insulation test cover (300). The movable end of the rotatable lifting seat (110) is installed on the outer wall of the bottom end of the test basin (200). The test basin (200) includes a vibration basin (220) and a vibration source (240). The vibration basin (220) is a bucket structure and is fixed on the outer edge of its top end by a sealing ring to tension the vibration basin (220) in the test basin (200). The vibration end of the vibration source (240) is connected to the outer wall of the bottom end of the vibration basin (220).

2. The wear resistance testing device for a rotating blade according to claim 1, characterized in that: An annular guide plate (310) is provided on the outer side wall of the soundproof test cover (300) near the tool head mounting seat (410). When the test particles (600) are emitted downward for testing, they are guided to the outer side wall of the test piece (700) by the guide plate (310).

3. The wear resistance testing device for a rotating blade according to claim 2, characterized in that: The invention also includes a planetary assembly, which is sleeved on the linkage shaft (440) and includes a driving gear (490), a gear ring (470) and a driven gear (480). The end of the flat sweeping frame (460) is extended with an insertion shaft, which is inserted into the driven gear (480). The end of the flat sweeping frame (460) is always connected to the inner wall of the sealing disk (430). When the driving motor (510) drives the linkage shaft (440) to rotate, it also drives the driving gear (490) to rotate. The driven gear (480) performs a circular motion between the gear ring (470) and the driving gear (490), and the flat sweeping frame (460) connected thereto sweeps flatly inside the sealing disk (430).

4. The wear resistance testing device for a rotating blade according to claim 3, characterized in that: The outer edge of the sliding ring (210) is provided with a groove, and the inner side wall of the sound insulation test cover (300) is provided with a vertical convex strip (230), and the groove is clamped on the outer wall of the convex strip (230).

5. The wear resistance testing device for a rotating blade according to claim 4, characterized in that: The test particles (600) are placed in the test basin (200), and the signal end of the test basin (200) is connected to an audio controller. The audio controller inputs signals of different frequencies into the test basin (200), so as to activate the test basin (200) and drive the test particles (600) to jump.

6. The wear resistance testing device for a rotating blade according to claim 5, characterized in that: The drive assembly (500) includes a drive motor (510) and a reducer (520), wherein the output shaft of the drive motor (510) is connected to the reducer (520), the reducer (520) is mounted on the output shaft of the drive motor (510), and the output shaft of the reducer (520) is connected to the linkage shaft (440).

7. The wear resistance testing device for a rotating blade according to claim 6, characterized in that: The shaft end of the linkage shaft (440) is provided with a connecting thread, and a plurality of limiting protrusions (441) are distributed on the outer wall of the linkage shaft (440) near the connecting thread. When the test piece (700) is mounted on the linkage shaft (440), the opening groove at the bottom end of the blade holder (710) is clamped on the outer wall of the limiting protrusion (441).

8. The wear resistance testing device for a rotating blade according to claim 7, characterized in that: A balance bearing is provided inside the flat sweeping frame (460), and when the piece to be tested (700) is mounted on the bottom end of the linkage shaft (440), the blade frame (710) is inserted into the balance bearing.

9. The wear resistance testing device for a rotating blade according to claim 8, characterized in that: The test piece (700) comprises a blade holder (710), a first blade (720) and a second blade (740); a connecting shaft is connected to the blade holder (710); the first blade (720) and the second blade (740) are superimposed and mounted on the connecting shaft in sequence; the shaft end of the connecting shaft is locked by a locking bolt (750); and a supporting washer (730) is provided at the connection between the first blade (720) and the second blade (740).

10. A method for testing the wear resistance of a rotating blade, characterized in that: The test is performed using a wear resistance testing device for a rotary blade as described in any one of claims 1 to 9, comprising the following steps: S100, preparation before testing: installing the test piece (700) on the linkage shaft (440), placing the test particles (600) into the vibration basin (220) and the sealing disk (430) of the test basin body (200), and installing the sound insulation test cover (300) on the base (100); S200, collecting images before testing: before testing, collecting images of the test piece (700) from the top, left, right, front and back views, with the image collection positions covering the blade surface and blade edge of the test piece (700); S300, test item 1: During the test, the driving assembly (500) drives the linkage shaft (440) and the test piece (700) thereon to rotate, and at the same time, the linkage shaft (440) drives the sweeping frame (460) to rotate in the sealing disk (430), so that the test particles (600) in the sealing disk (430) are swept into the leak hole (450) and fall, impacting the test piece (700); S400, test item 2: based on step S300, a signal is input to the test basin (200), and different frequency signals are input to achieve different height jumps of the test particles (600), and the knife surface and the blade of the test piece (700) are tested separately or both at the same time; S500, result comparison: set a set of test cycles for the above two test items. After the test, take a picture of the test piece (700) at a position that is consistent with the initial picture taking position, and compare it with the initial picture taking photo to observe whether there is any obvious damage on the blade and the blade surface.

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