Efficient material conveying centrifugal fan with non-axial air inlet

Abstract

The invention relates to the field of centrifugal fan industry, in particular to an efficient material conveying centrifugal fan with a non-axial air inlet, which comprises a volute, an impeller fixedly arranged in the volute and the air inlet fixedly connected with the volute, the air inlet partially extends into the volute, the air inlet and the impeller are non-coaxially arranged, and a gap is arranged between the air inlet and the impeller; the air inlet comprises a connecting part, an air guide section, an air inlet part and an air guide part, the air guide section is fixedly connected with the volute through the connecting part, an inlet of the air guide section forms the air inlet part, and an outlet of the air guide section forms the air guide part; the air guide section is of an oblique cylinder structure. According to the efficient material conveying centrifugal fan with the non-axial air inlet, the design of the non-axial air inlet, the impeller without a front disc and a matched volute molded line is adopted, and the problem that in the prior art, due to material blockage such as bayonet overstock during feeding and conveying of a material conveying centrifugal fan, the material conveying efficiency is low is solved.

Description

Technical Field

[0001] The present invention relates to the field of centrifugal fan industry, and in particular to a high-efficiency material conveying centrifugal fan with a non-axial air inlet. Background Art

[0002] Centrifugal fans are widely used in various sectors of the national economy as supporting conveying equipment for conveying air, grain, feed, mineral powder, production raw materials, production waste, and other materials. For example, the production and processing of cardboard boxes generates a large amount of scrap. Since the production line processes cardboard boxes at a high speed, the traditional method is to set up a dedicated station to remove the excess product scraps and recycle them for reuse. However, manual collection and recycling of scraps is inefficient. Therefore, material conveying centrifugal fans are needed to collect and recycle the large amount of scraps during cardboard box production to improve efficiency.

[0003] When using a centrifugal fan for material conveying, it is important to ensure accurate material delivery. Materials are conveyed through the fan through the air duct, and during this process, the material passes through the fan body. However, due to the structural characteristics of conventional fans, there is a risk of material blockage during feeding and conveying, such as material backlogs. This prevents smooth material delivery through the fan body, reducing conveying efficiency and impacting normal production.

[0004] The existing material conveying centrifugal fans need to be improved. Summary of the Invention

[0005] The purpose of the present invention is to provide a high-efficiency material conveying centrifugal fan with a non-axial air inlet, aiming to solve the problem of low material conveying efficiency caused by material blockage such as card hole backlog during feeding and conveying in the material conveying centrifugal fan in the prior art.

[0006] In order to achieve the above-mentioned object, a high-efficiency material conveying centrifugal fan with a non-axial air inlet comprises a volute, an impeller fixedly arranged in the volute, and an air inlet fixedly connected to the volute; The air inlet part extends into the volute, the air inlet and the impeller are not coaxially arranged, and a gap is set between the air inlet and the impeller; The air inlet includes a connecting portion, an air guide section, an air inlet portion and an air guide portion. The air guide section is fixedly connected to the volute through the connecting portion. The inlet of the air guide section forms the air inlet portion, and the outlet of the air guide section forms the air guide portion. The air guide section is set to an oblique cylindrical structure. In the top view of the air guide section, the angle ∠1 between the air guide section and the air guide portion is 75°-76°. The radius of the air inlet portion is R1, and the radius of the air guide portion is R2. R1 and R2 are equal and both are 94mm-95mm. The vertical distance L2 between the air inlet portion and the connecting portion is 99 mm to 101 mm, and the vertical distance L1 between the air guide portion and the connecting portion is 14.6 mm to 15.4 mm.

[0007] Furthermore, ∠1 is 75.58°, R1 is 94.5 mm, L2 is 100 mm, and L1 is 15 mm.

[0008] Furthermore, the impeller includes a hub and a rear disc, the rear disc being fixedly mounted on the hub and having a plurality of blades arranged in an array around the rear disc; The blade includes a straight blade portion close to the hub and an arc blade portion away from the hub. The straight blade portion includes a straight segment away from the hub and an inclined segment close to the hub. The inclined segment is inclined from the straight segment toward the hub.

[0009] Furthermore, the vertical distance L3 between the trailing edge of the blade and the rear disc is 119 mm to 121.2 mm; The impeller is cut with a plane passing through the central axis of the impeller. On the cross section, the length L1 of the inclined section is 84mm-86mm, the length L2 of the straight section is 30.2mm-40.2mm, the angle ∠4 between the inclined section and the straight section is 134°-136°, and the vertical distance L8 between the straight section and the air guide part is 12.8mm-13.2mm.

[0010] Furthermore, the inlet angle ∠2 when the blade is installed is 11°-11.6°, the outlet angle ∠3 when the blade is installed is 34.5°-35.5°, and on the projection surface of the rear disc, the radius R3 of the arc blade portion is 69mm-70mm and the arc length is 80mm-81.5mm; The diameter φ1 of the outer circle formed by the outer ends of all blades of the impeller is 400mm, and the diameter φ2 of the outer circle formed by the outer ends of the straight blades is 263mm-266.5mm; The thickness t1 of the blade is 4.8 mm to 5.2 mm, and there are 8 blades.

[0011] Furthermore, a wear-resistant weld is provided on the arc blade portion, and the thickness t2 of the wear-resistant weld is 2.4mm-2.6mm; L3 is 120mm, L1 is 84.9mm, L2 is 30.7mm, ∠4 is 135°, L8 is 13mm, ∠2 is 11.3°, ∠3 is 35°, R3 is 69.6mm and the arc length is 80.7mm, φ2 is 264.8mm, and t1 is 5mm.

[0012] Furthermore, the profile of the volute includes a first diffuser straight segment, a volute tongue segment, a first arc segment, a second arc segment, a third arc segment, a fourth arc segment, and a second diffuser straight segment that are tangentially connected in sequence; the first diffuser straight segment and the second diffuser straight segment enclose an air outlet, and the first arc segment, the second arc segment, the third arc segment, and the fourth arc segment are not cocentric; A rectangular coordinate system is established with the center of the impeller as the coordinate origin. When the first diffuser straight line segment is located in the third quadrant, the coordinates of the center O2 of the first arc segment are (-21.8, 21.8), the radius R5 is 223mm-225mm and the arc length is 123mm-126mm. The coordinates of the center O1 of the second arc segment are (21.8, 21.8), the radius R6 is 244.7mm-247.3mm and the arc length is 384.5mm-3 88mm, the coordinates of the center O4 of the third arc segment are (21.8, -21.8), the radius R7 is 266.4mm-269.6mm and the arc length is 418mm-423.5mm, the coordinates of the center O3 of the fourth arc segment are (-21.8, -21.8), the radius R8 is 288mm-292mm and the arc length is 452mm-458m, and the first diffuser straight line segment and the second diffuser straight line segment are both set perpendicular to the air outlet.

[0013] Furthermore, the width L5 of the air outlet is 159mm-161mm, and the height L4 is 170mm-174mm; The radius R4 of the volute tongue segment is 13.5mm-14.5mm and the arc length is 29mm-30.5mm, the length L6 of the first diffuser straight segment is 27mm-28mm, and the length L7 of the second diffuser straight segment is 228mm-232mm. A tangent is drawn to the volute tongue segment with the tangent point of the volute tongue segment and the first arc segment as the tangent point. The angle ∠5 between the tangent and the first diffuser straight segment is 57.9°-58.5°.

[0014] Furthermore, a rectangular coordinate system is established with the center of the impeller as the coordinate origin. When the first diffuser straight segment is located in the third quadrant, the coordinates of the center O2 of the first arc segment are (-21.8, 21.8), the radius R5 is 224 mm, and the arc length is 124.4 mm. The coordinates of the center O1 of the second arc segment are (21.8, 21.8), the radius R6 is 246 mm, and the arc length is 386.4 mm. The coordinates of the center O4 of the third arc segment are (21.8, -21.8), the radius R7 is 268 mm, and the arc length is 420.7 mm. The coordinates of the center O3 of the fourth arc segment are (-21.8, -21.8), the radius R8 is 290 mm, and the arc length is 454.9 m. L5 is 160mm, L4 is 172mm, R4 is 14mm and the arc length is 29.8mm, L6 is 27.5mm, L7 is 229.9mm, and ∠5 is 58.22°.

[0015] Furthermore, it also includes a motor and a base. The motor is connected to the impeller through a motor shaft, and the volute and the motor are fixedly arranged on the base.

[0016] The present invention provides a high-efficiency material conveying centrifugal fan with a non-axial air inlet: (1) The non-axial air inlet is designed to be non-coaxial with the impeller, realizing a non-coaxial air and material intake method, replacing the concentric axial air and material intake method of the traditional process, effectively avoiding blockage caused by shaft disc problems and improving material conveying efficiency; (2) The impeller design without a front disc increases the material feed flowability, further improves the material conveying efficiency, and effectively reduces the impact loss and noise of the airflow on the impeller inlet. At the same time, adding wear-resistant welding on the working surface of the blade has an anti-wear effect, which increases the working life of the fan. (3) The arc transition structure of the logarithmic spiral volute profile ensures smooth and efficient airflow in the volute, reduces the impact and energy loss of the airflow, and thus improves the efficiency of the fan; by optimizing the air outlet and the volute tongue section of the volute to match the impeller, the impact loss and separation of the airflow are reduced, the fan's efficient operating range is widened, the total pressure and fan efficiency are improved, the material conveying efficiency is further improved, and the fan noise is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the centrifugal fan of the present invention; Figure 2 Schematic diagram of the volute profile; Figure 3 Schematic diagram of the side cross-sectional structure of the volute; Figure 4 is a structural diagram of the impeller; Figure 5 Schematic diagram of the side cross-sectional structure of the impeller; Figure 6 is a top sectional view of the air inlet; Figure 7 It is a performance curve diagram of the high-efficiency material conveying centrifugal fan with non-axial air inlet of the present invention; Figure 8 It is a performance curve diagram of the comparison ratio.

[0018] Description of reference numerals: Volute 1; first diffuser straight section 11; volute tongue section 12; first arc segment 13; second arc segment 14; third arc segment 15; fourth arc segment 16; second diffuser straight section 17; air outlet 18; Impeller 2; blade 21; straight blade portion 211; inclined segment 2111; straight segment 2112; arc blade portion 212; wear-resistant weld 2121; rear disc 22; Air inlet 3; connecting portion 31; air guide section 32; air inlet portion 33; air guide portion 34; Motor 4; base 5. DETAILED DESCRIPTION

[0019] The present invention is described in detail below with reference to specific embodiments.

[0020] In the present invention, unless otherwise expressly specified and limited, when terms such as "set on", "connected", and "connected" appear, these terms should be understood in a broad sense. For example, they can be fixedly connected, detachably connected, or integrally connected; they can be directly connected or connected through one or more intermediate media. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. The directional words that appear in the present invention are to better illustrate the characteristics of the features and the relationship between the features. It should be understood that when the placement direction of the present invention changes, the characteristics of the features and the direction of the relationship between the features also change accordingly. Therefore, the directional words do not constitute an absolute limitation on the characteristics of the features and the relationship between the features in space, but only play a relative limitation role.

[0021] The structural parameters adopted in the present invention are only for illustrating the technical solution of the present invention. That is, based on the basic structural parameters of the present invention, reasonable proportional scaling can be performed in actual production (for example, when the diameter of the impeller is 400 mm, it can be scaled 0.1-30 times, etc.), and such reasonable proportional scaling also falls within the scope of protection of the present invention.

[0022] See also Figure 1-8 , a high-efficiency material conveying centrifugal fan with a non-axial air inlet, comprising a volute 1, an impeller 2 fixedly arranged in the volute 1 and an air inlet 3 fixedly connected to the volute 1; The air inlet 3 partially extends into the volute 1, and the air inlet 3 and the impeller 2 are not coaxially arranged, and a gap is set between the air inlet 3 and the impeller 2; The air inlet 3 includes a connecting portion 31, an air guiding section 32, an air inlet portion 33 and an air guiding portion 34. The air guiding section 32 is fixedly connected to the volute 1 through the connecting portion 31. The inlet of the air guiding section 32 forms the air inlet portion 33, and the outlet of the air guiding section 32 forms the air guiding portion 34. The air guide section 32 is configured as an oblique cylindrical structure. In a top view of the air guide section 32 , the angle ∠1 between the air guide section 32 and the air guide portion 34 is 75°-76°. The radius of the air inlet portion 33 is R1, and the radius of the air guide portion 34 is R2. R1 and R2 are equal and both are 94mm-95mm. A vertical distance L2 between the air inlet portion 33 and the connecting portion 31 is 99 mm to 101 mm, and a vertical distance L1 between the air guide portion 34 and the connecting portion 31 is 14.6 mm to 15.4 mm.

[0023] Preferably, ∠1 is 75.58°, R1 is 94.5 mm, L2 is 100 mm, and L1 is 15 mm.

[0024] Through the above technical solution, a non-axial air inlet 3 is adopted, and the air inlet 3 and the impeller 2 are designed to be non-coaxial, thereby realizing a non-coaxial air intake and material intake method, replacing the concentric axial (i.e., center axial) air intake and material intake method of the traditional process, effectively avoiding blockage caused by shaft disc problems, and improving material conveying efficiency.

[0025] In this embodiment, the impeller 2 includes a hub and a rear disc 22 , the rear disc 22 is fixedly mounted on the hub, and a plurality of blades 21 are arranged in an array around the rear disc 22 ; The blade 21 includes a straight blade portion 211 close to the hub and an arc blade portion 212 away from the hub. The straight blade portion 211 includes a straight segment 2112 away from the hub and an inclined segment 2111 close to the hub. The inclined segment 2111 is inclined from the straight segment 2112 toward the hub.

[0026] In this embodiment, the vertical distance L3 between the trailing edge of the blade 21 and the rear disc 22 is 119 mm to 121.2 mm; preferably, L3 is 120 mm; The impeller 2 is cut along a plane passing through the central axis of the impeller 2. In the cross section, the length L1 of the inclined section 2111 is 84 mm to 86 mm, the length L2 of the straight section 2112 is 30.2 mm to 40.2 mm, the angle ∠4 between the inclined section 2111 and the straight section 2112 is 134° to 136°, and the vertical distance L8 between the straight section 2112 and the air guide 34 is 12.8 mm to 13.2 mm. Preferably, L1 is 84.9 mm, L2 is 30.7 mm, ∠4 is 135°, and L8 is 13 mm. In this embodiment, the inlet angle ∠2 of the blade 21 when installed is 11°-11.6°, and the outlet angle ∠3 of the blade 21 when installed is 34.5°-35.5°. On the projection surface of the rear disc 22, the radius R3 of the arc blade portion 212 is 69 mm-70 mm and the arc length is 80 mm-81.5 mm. Preferably, ∠2 is 11.3°, ∠3 is 35°, R3 is 69.6 mm, and the arc length is 80.7 mm. The diameter φ1 of the outer circle formed by the outer ends of all blades 21 of the impeller 2 is 400 mm, and the diameter φ2 of the outer circle formed by the outer ends of the straight blade portion 211 is 263 mm-266.5 mm; preferably, φ2 is 264.8 mm; The thickness t1 of the blade 21 is 4.8 mm to 5.2 mm, and there are 8 blades 21. Preferably, t1 is 5 mm.

[0027] Furthermore, a wear-resistant weld 2121 is provided on the arc blade portion, and the thickness t2 of the wear-resistant weld 2121 is 2.4 mm-2.6 mm; preferably, t2 is 2.5 mm.

[0028] Through the above technical solution, the impeller 2 is designed without a front disc, which increases the feed fluidity of the material, further improves the material conveying efficiency, and can effectively reduce the impact loss and noise of the airflow on the inlet of the impeller 2; at the same time, the wear-resistant welding 2121 is added to the working surface of the blade 21 to play an anti-wear effect, and the cancellation of the front disc can reduce the weight of the impeller 2 and increase the working life of the fan.

[0029] In this embodiment, the profile of the volute 1 includes a first diffuser straight segment 11, a volute tongue segment 12, a first arc segment 13, a second arc segment 14, a third arc segment 15, a fourth arc segment 16, and a second diffuser straight segment 17, which are tangentially connected in sequence. The first diffuser straight segment 11 and the second diffuser straight segment 17 enclose an air outlet 18, and the first arc segment 13, the second arc segment 14, the third arc segment 15, and the fourth arc segment 16 are not cocentric. A rectangular coordinate system is established with the center of the impeller 2 as the coordinate origin. When the first diffuser straight segment 11 is located in the third quadrant, the coordinates of the center O2 of the first arc segment 13 are (-21.8, 21.8), the radius R5 is 223mm-225mm and the arc length is 123mm-126mm. The coordinates of the center O1 of the second arc segment 14 are (21.8, 21.8), the radius R6 is 244.7mm-247.3mm and the arc length is 384.5mm-388. mm, the coordinates of the center O4 of the third arc segment 15 are (21.8, -21.8), the radius R7 is 266.4mm-269.6mm and the arc length is 418mm-423.5mm, the coordinates of the center O3 of the fourth arc segment 16 are (-21.8, -21.8), the radius R8 is 288mm-292mm and the arc length is 452mm-458m, and the first diffuser straight segment 11 and the second diffuser straight segment 17 are both arranged perpendicular to the air outlet 18.

[0030] Preferably, a rectangular coordinate system is established with the center of the impeller 2 as the coordinate origin. When the first diffuser straight segment 11 is located in the third quadrant, the coordinates of the center O2 of the first arc segment 13 are (-21.8, 21.8), the radius R5 is 224 mm, and the arc length is 124.4 mm. The coordinates of the center O1 of the second arc segment 14 are (21.8, 21.8), the radius R6 is 246 mm, and the arc length is 386.4 mm. The coordinates of the center O4 of the third arc segment 15 are (21.8, -21.8), the radius R7 is 268 mm, and the arc length is 420.7 mm. The coordinates of the center O3 of the fourth arc segment 16 are (-21.8, -21.8), the radius R8 is 290 mm, and the arc length is 454.9 m.

[0031] In this embodiment, the width L5 of the air outlet 18 is 159 mm to 161 mm, and the height L4 is 170 mm to 174 mm; The radius R4 of the tongue segment 12 is 13.5mm-14.5mm, and the arc length is 29mm-30.5mm. The length L6 of the first diffuser straight segment 11 is 27mm-28mm, and the length L7 of the second diffuser straight segment 17 is 228mm-232mm. A tangent line drawn through the tongue segment 12 at the point of tangency between the tongue segment 12 and the first arc segment 13 is an angle ∠5 between the tangent line and the first diffuser straight segment 11 of 57.9°-58.5°. Preferably, L5 is 160mm, L4 is 172mm, R4 is 14mm, the arc length is 29.8mm, L6 is 27.5mm, L7 is 229.9mm, and ∠5 is 58.22°.

[0032] In this embodiment, a motor 4 and a machine base 5 are further included. The motor 4 is transmission-connected to the impeller 2 via a motor shaft. The volute 1 and the motor 4 are both fixedly mounted on the machine base 5 .

[0033] Through the above technical solution, the arc transition structure of the logarithmic spiral volute 1 profile is adopted to ensure smooth and efficient airflow in the volute 1, reduce the impact and energy loss of the airflow, and thus improve the efficiency of the fan; by optimizing the air outlet and the volute tongue section 12 of the volute 1 to match the impeller 2, the impact loss and separation of the airflow are reduced, the fan's efficient operating range is widened, the total pressure and fan efficiency are improved, the material conveying efficiency is further improved and the fan noise is reduced.

[0034] In order to verify this embodiment, based on the preferred structural parameters provided in this embodiment, a high-efficiency material conveying centrifugal fan with a non-axial air inlet was manufactured with an impeller 2 having a diameter of 400 mm (i.e., the diameter of the outer circle surrounded by the outer ends of all blades 21 of the impeller 2) as a test example for testing. At the same time, a traditional material conveying centrifugal fan with a coaxial impeller and air inlet was manufactured with an impeller 2 having a traditional diameter of 400 mm as a comparative example for testing. The test results were converted to an atmospheric pressure of 101325 Pa, an atmospheric temperature of 20°C, a fan speed of 2900 r / min, and a medium density of 1.2 kg / m 3 The test data under the test conditions, the test case obtained the test data shown in Table 1 and Figure 7 The performance curve shown in Table 2 is obtained as a comparative example. Figure 8 The performance curve shown is based on volume flow as the horizontal axis. In the performance curve, qvsglGu is the volume flow, LAGu is the A sound level, ηr is the fan efficiency, PrGu is the impeller power, pFGu is the total pressure, and psFGu is the static pressure.

[0035] Table 1

[0036] Table 2

[0037] From the test data and performance curves, it can be seen that the comparative example is inferior to the test example in terms of volume flow range, total pressure, fan efficiency and A sound level. In contrast, the volume flow range of the test example is 1325.5m 3 / h-4417.2m 3 / h, the optimal fan efficiency is 68.978%, the total pressure is 3232.2Pa, and the A sound level is 89.495dB; the volume flow range of the test case is 1612.5m 3 / h-4062.4m 3 / h, the optimal fan efficiency was 65.987%, the total pressure was 2292.9 Pa, and the A-sound level was 95.264 dB. The test cases generally had a wider volume flow range, higher total pressure, and higher fan efficiency than the comparison cases, and the A-sound level of the test cases was generally lower than that of the comparison cases.

[0038] Compared with the prior art, the present invention provides a high-efficiency material conveying centrifugal fan with a non-axial air inlet. By adopting a non-axial air inlet, an impeller without a front disc and a matching volute profile design, it improves the problem of low material conveying efficiency caused by material blockage such as card slot backlog during feeding and conveying in the prior art material conveying centrifugal fans.

[0039] In the absence of conflict, the above embodiments and features therein may be combined with each other.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A high-efficiency material conveying centrifugal fan with a non-axial air inlet, comprising a volute, an impeller fixedly disposed within the volute, and an air inlet fixedly connected to the volute, characterized in that: The air inlet part extends into the volute, the air inlet and the impeller are not coaxially arranged, and a gap is set between the air inlet and the impeller; The air inlet includes a connecting portion, an air guide section, an air inlet portion and an air guide portion. The air guide section is fixedly connected to the volute through the connecting portion. The inlet of the air guide section forms the air inlet portion, and the outlet of the air guide section forms the air guide portion. The air guide section is set to an oblique cylindrical structure. In the top view of the air guide section, the angle ∠1 between the air guide section and the air guide portion is 75°-76°. The radius of the air inlet portion is R1, and the radius of the air guide portion is R2. R1 and R2 are equal and both are 94mm-95mm. The vertical distance L2 between the air inlet portion and the connecting portion is 99 mm to 101 mm, and the vertical distance L1 between the air guide portion and the connecting portion is 14.6 mm to 15.4 mm.

2. The high-efficiency material conveying centrifugal fan with a non-axial air inlet according to claim 1, characterized in that: ∠1 is 75.58°, R1 is 94.5mm, L2 is 100mm, and L1 is 15mm.

3. The high-efficiency material conveying centrifugal fan with a non-axial air inlet according to claim 2, characterized in that: The impeller includes a hub and a rear disc, wherein the rear disc is fixedly mounted on the hub and has a plurality of blades arranged in an array around the rear disc; The blade includes a straight blade portion close to the hub and an arc blade portion away from the hub. The straight blade portion includes a straight segment away from the hub and an inclined segment close to the hub. The inclined segment is inclined from the straight segment toward the hub.

4. The high-efficiency material conveying centrifugal fan with a non-axial air inlet according to claim 3, characterized in that: The vertical distance L3 between the trailing edge of the blade and the rear disc is 119mm-121.2mm; The impeller is cut with a plane passing through the central axis of the impeller. On the cross section, the length L1 of the inclined section is 84mm-86mm, the length L2 of the straight section is 30.2mm-40.2mm, the angle ∠4 between the inclined section and the straight section is 134°-136°, and the vertical distance L8 between the straight section and the air guide part is 12.8mm-13.2mm.

5. The high-efficiency material conveying centrifugal fan with a non-axial air inlet according to claim 4, characterized in that: The inlet angle ∠2 when the blade is installed is 11°-11.6°, the outlet angle ∠3 when the blade is installed is 34.5°-35.5°, and on the projection surface of the rear disc, the radius R3 of the arc blade portion is 69mm-70mm and the arc length is 80mm-81.5mm; The diameter φ1 of the outer circle formed by the outer ends of all blades of the impeller is 400mm, and the diameter φ2 of the outer circle formed by the outer ends of the straight blades is 263mm-266.5mm; The thickness t1 of the blade is 4.8 mm to 5.2 mm, and there are 8 blades.

6. The high-efficiency material conveying centrifugal fan with a non-axial air inlet according to claim 5, characterized in that: The arc blade is provided with a wear-resistant weld, and the thickness t2 of the wear-resistant weld is 2.4mm-2.6mm; L3 is 120mm, L1 is 84.9mm, L2 is 30.7mm, ∠4 is 135°, L8 is 13mm, ∠2 is 11.3°, ∠3 is 35°, R3 is 69.6mm and the arc length is 80.7mm, φ2 is 264.8mm, and t1 is 5mm.

7. The high-efficiency material conveying centrifugal fan with a non-axial air inlet according to claim 6, characterized in that: The profile of the volute includes a first diffuser straight segment, a volute tongue segment, a first arc segment, a second arc segment, a third arc segment, a fourth arc segment, and a second diffuser straight segment, which are sequentially connected tangentially; the first diffuser straight segment and the second diffuser straight segment enclose an air outlet, and the first arc segment, the second arc segment, the third arc segment, and the fourth arc segment are not cocentric; A rectangular coordinate system is established with the center of the impeller as the coordinate origin. When the first diffuser straight line segment is located in the third quadrant, the coordinates of the center O2 of the first arc segment are (-21.8, 21.8), the radius R5 is 223mm-225mm and the arc length is 123mm-126mm. The coordinates of the center O1 of the second arc segment are (21.8, 21.8), the radius R6 is 244.7mm-247.3mm and the arc length is 384.5mm-3 88mm, the coordinates of the center O4 of the third arc segment are (21.8, -21.8), the radius R7 is 266.4mm-269.6mm and the arc length is 418mm-423.5mm, the coordinates of the center O3 of the fourth arc segment are (-21.8, -21.8), the radius R8 is 288mm-292mm and the arc length is 452mm-458m, and the first diffuser straight line segment and the second diffuser straight line segment are both set perpendicular to the air outlet.

8. The high-efficiency material conveying centrifugal fan with a non-axial air inlet according to claim 7, characterized in that: The width L5 of the air outlet is 159mm-161mm, and the height L4 is 170mm-174mm; The radius R4 of the volute tongue segment is 13.5mm-14.5mm and the arc length is 29mm-30.5mm, the length L6 of the first diffuser straight segment is 27mm-28mm, and the length L7 of the second diffuser straight segment is 228mm-232mm. A tangent is drawn to the volute tongue segment with the tangent point of the volute tongue segment and the first arc segment as the tangent point. The angle ∠5 between the tangent and the first diffuser straight segment is 57.9°-58.5°.

9. The high-efficiency material conveying centrifugal fan with a non-axial air inlet according to claim 8, characterized in that: A rectangular coordinate system is established with the center of the impeller as the coordinate origin. When the first diffuser straight segment is located in the third quadrant, the coordinates of the center O2 of the first arc segment are (-21.8, 21.8), the radius R5 is 224 mm, and the arc length is 124.4 mm. The coordinates of the center O1 of the second arc segment are (21.8, 21.8), the radius R6 is 246 mm, and the arc length is 386.4 mm. The coordinates of the center O4 of the third arc segment are (21.8, -21.8), the radius R7 is 268 mm, and the arc length is 420.7 mm. The coordinates of the center O3 of the fourth arc segment are (-21.8, -21.8), the radius R8 is 290 mm, and the arc length is 454.9 m. L5 is 160mm, L4 is 172mm, R4 is 14mm and the arc length is 29.8mm, L6 is 27.5mm, L7 is 229.9mm, and ∠5 is 58.22°.

10. The high-efficiency material conveying centrifugal fan with a non-axial air inlet according to claim 9, characterized in that: It also includes a motor and a base. The motor is connected to the impeller through a motor shaft, and the volute and the motor are fixed on the base.

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