Centrifugal fan

Abstract

The utility model provides a centrifugal fan which solves the problem that an existing fan is poor in performance. The centrifugal fan comprises a volute with two open ends and one side provided with an air outlet, air guide rings are fixed in the two open ends, an impeller is arranged in the volute, a rotating shaft is horizontally arranged in the volute, the two ends of the rotating shaft are rotationally supported on the two air guide rings respectively, and the impeller comprises an annular wheel disc and annular cover plates, a circle of blades are arranged between the two annular cover plates and the annular wheel disc, baffle rings are integrally formed on the back-to-back end faces of the two annular cover plates, the baffle rings and the annular cover plates are coaxially arranged, convex rings are correspondingly formed on the two air guide rings, and the two baffle rings are arranged outside the two convex rings in a sleeving mode correspondingly; and the baffle rings and the convex rings which correspond to each other in position are in clearance fit to form an annular labyrinth channel. The centrifugal fan is good in performance.

Description

Technical Field

[0001] The utility model relates to a fan, in particular to a centrifugal fan. Background Art

[0002] A centrifugal fan is a machine that relies on input mechanical energy to increase gas pressure and discharge gas. It is a driven fluid machine and is widely used in ventilation, dust removal and cooling of factories, mines, tunnels, cooling towers, vehicles, ships and buildings, as well as ventilation and draft of boilers and industrial furnaces.

[0003] Existing centrifugal fans, such as an impeller-combined dual-impedance fan disclosed in the China Patent Library (application number: 201210366125.7), include an impeller consisting of two parts with different shapes and structures inside and outside. As an optimized design of the present invention, the inner half of the impeller is a centrifugal straight blade, and the outer half is a spiral suction blade; the impeller is installed in a specially shaped volute through a motor output shaft with a nut. This layout of impellers with different shapes inside and outside fully utilizes the advantages of the powerful suction of the spiral suction blade and the large wind output of the centrifugal straight blade, so that the impeller is driven by a low motor speed, and the outlet of the specially shaped volute blows out strong wind with a certain pressure, and can be installed at the other end of the motor with the same structure.

[0004] In the above-mentioned fan, there is a certain gap between the air inlet end of the wind wheel and the inner wall of the volute, which not only causes air leakage, but also some wind flows directly to the side of the wind wheel through the gap, hindering the exhaust of the wind wheel and affecting the performance and efficiency of the fan. Utility Model Content

[0005] The utility model aims to solve the above problems in the prior art and proposes a centrifugal fan to improve the performance.

[0006] The purpose of the utility model can be achieved through the following technical solutions: a centrifugal fan, including a volute with open ends and an air outlet on one side, air guide rings are fixed in the two openings, an impeller and a horizontal rotating shaft are arranged in the volute, and the two ends of the rotating shaft are rotatably supported on the two air guide rings, the impeller includes an annular wheel disk sleeved and fixed on the rotating shaft and annular cover plates arranged on both sides of the annular wheel disk, a circle of blades is arranged between the two annular cover plates and the annular wheel disks, and it is characterized in that retaining rings are integrally formed on the end surfaces of the two annular cover plates facing each other, and the retaining rings are coaxially arranged with the annular cover plates, and convex rings are correspondingly formed on the two air guide rings, and the two retaining rings are respectively sleeved outside the two convex rings; the retaining rings and the convex rings corresponding in position are gap-matched to form a ring-shaped maze channel.

[0007] During actual installation, a motor is arranged on one side of the volute, and the motor drives the rotating shaft to rotate through a belt drive to drive the impeller to operate, so that the wind enters the impeller through the air guide ring and is thrown out from the side of the impeller, and finally discharged through the volute outlet.

[0008] The annular cover plate and the corresponding annular wheel disc are matched through the clearance of the retaining ring and the convex ring, so that the annular cover plate and the annular wheel disc can achieve a labyrinth seal without contact, effectively reducing air intake leakage, allowing the wind to completely enter the impeller and be thrown out sideways, thereby improving the efficiency and performance of the centrifugal fan.

[0009] In the above-mentioned centrifugal fan, the thickness of the retaining ring is smaller than the size of the corresponding end face of the annular cover plate, and the axial cross-section of the labyrinth channel is roughly L-shaped, so as to enhance the sealing performance formed between the annular cover plate and the annular wheel, thereby making the centrifugal fan more efficient.

[0010] In the above centrifugal fan, the width of the labyrinth channel is approximately 0.5 mm to 2 mm.

[0011] In the above-mentioned centrifugal fan, an annular step is formed between the inner wall of the convex ring and the end face of the corresponding air guide ring to form an avoidance, thereby reducing the amount of wind gathered in the maze channel.

[0012] In the above centrifugal fan, both air guide rings are provided with connecting parts, which include a ring body sleeved on the rotating shaft and a connecting strip formed on the side wall of the ring body, and the length of the connecting strip extends along the radial direction of the ring body, there are at least two connecting strips and they are evenly spaced along the circumference of the ring body, and one end of the connecting strip is fixedly connected to the corresponding air guide ring, and both ends of the rotating shaft are rotatably supported on the two ring bodies through bearings. The above design is adopted to facilitate the support and positioning of the rotating shaft.

[0013] In the above-mentioned centrifugal fan, the bearing comprises an inner ring and an outer ring, and both the inner ring and the outer ring are fixedly connected to the rotating shaft and the corresponding ring body respectively by interference fit.

[0014] In the above centrifugal fan, the two connecting parts are symmetrically arranged, a ring-shaped limit seat is formed on the inner wall of the ring body, two annular shoulders are formed on the side wall of the rotating shaft, the adjacent ends of the two inner rings are pressed on the two annular shoulders respectively, and the opposite ends of the two outer rings are pressed on the two limit seats respectively. With the cooperation of the two annular shoulders and the two limit seats, the two bearings are effectively limited in the axial direction, effectively ensuring the stable rotation of the rotating shaft, so that the purpose of improving the performance of the centrifugal fan is stably achieved.

[0015] In the above centrifugal fan, annular sealing seats are formed on the outer walls of the opposite ends of the two air guide rings. The two sealing seats are pressed tightly against the two end surfaces of the volute respectively, and the sealing seats are fixedly connected to the volute.

[0016] In the above-mentioned centrifugal fan, a circle of through holes one is horizontally passed through the sealing seat, and the volute is provided with threaded holes. The threaded holes and through holes one are the same in number and their positions correspond one to one. The sealing seat is fixedly connected to the volute by screws that pass through through holes one and are screwed into corresponding threaded holes.

[0017] In the above-mentioned centrifugal fan, the connecting strip is provided with two through holes for one of the screw rods to pass through, and the connecting strip is clamped and positioned between the corresponding sealing seat and the corresponding screw head. That is, at this time, some screws are used to simultaneously position the connecting piece and the air guide ring to simplify the structure and facilitate assembly.

[0018] Compared with the existing technology, this centrifugal fan has the following advantages:

[0019] 1. The annular cover plate and the corresponding annular wheel disc are matched through the clearance of the retaining ring and the convex ring, so that the annular cover plate and the annular wheel disc can achieve a labyrinth seal without contact, effectively reducing air intake leakage and improving the efficiency and performance of the centrifugal fan.

[0020] 2. With the cooperation of two annular shoulders and two limit seats, the two bearings are effectively limited in the axial direction, which effectively ensures the stable rotation of the shaft and stably achieves the purpose of improving the performance of the centrifugal fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a three-dimensional schematic diagram of the centrifugal fan.

[0022] Figure 2 It is a cross-sectional schematic diagram of the centrifugal fan.

[0023] Figure 3 yes Figure 2 A magnified schematic diagram of center A.

[0024] Figure 4 yes Figure 2 A magnified schematic diagram of point B in the middle.

[0025] In the figure, 1, volute; 1a, air outlet; 2, air guide ring; 2a, convex ring; 2b, sealing seat; 3, impeller; 3a, annular wheel disk; 3b, annular cover plate; 3b1, retaining ring; 3c, blade; 4, rotating shaft; 4a, annular shoulder; 5, labyrinth passage; 6, connecting piece; 6a, ring body; 6a1, limit seat; 6b, connecting strip; 7, bearing; 7a, inner ring; 7b, outer ring; 8, annular step. DETAILED DESCRIPTION

[0026] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0027] like Figure 1As shown, the centrifugal fan comprises a volute 1 with two open ends and an air outlet 1a on one side. Air guide rings 2 are fixed in both open ends, the two air guide rings 2 are symmetrically arranged, and the inner holes of the air guide rings 2 are the air inlets of the volute 1.

[0028] Specifically,

[0029] The volute 1 is provided with an impeller 3 and a rotating shaft 4, the rotating shaft 4 is arranged horizontally, and the axis of the rotating shaft 4 extends along the two opening arrangement directions. The two ends of the rotating shaft 4 pass through the two air guide rings 2 respectively, and the two ends of the rotating shaft 4 are rotatably supported on the two air guide rings 2 respectively.

[0030] like Figure 2 As shown, the impeller 3 includes an annular wheel disc 3a sleeved and fixed on the rotating shaft 4 and annular cover plates 3b arranged on both sides of the annular wheel disc 3a, the annular cover plates 3b and the annular wheel disc 3a are arranged coaxially, the two annular cover plates 3b are distributed and symmetrically arranged along the axial direction of the rotating shaft 4, and a circle of blades 3c is arranged between the two annular cover plates 3b and the annular wheel disc 3a. In the actual product, the annular wheel disc 3a and the blades 3c are an integrated structure, and the blades 3c are welded and fixedly connected to the annular cover plates 3b.

[0031] Among them, Figure 2 and Figure 4 As shown, the two annular cover plates 3b have baffle rings 3b1 integrally formed on the end faces facing each other, and the baffle rings 3b1 are coaxially arranged with the annular cover plates 3b. The two air guide rings 2 are correspondingly formed with convex rings 2a, and the two baffle rings 3b1 are respectively sleeved outside the two convex rings 2a; the baffle rings 3b1 and the convex rings 2a corresponding in position are gap-matched to form an annular labyrinth channel 5. It is further explained that the thickness of the baffle ring 3b1 is smaller than the size of the corresponding end face of the annular cover plate 3b, and the axial cross-section of the labyrinth channel 5 is roughly L-shaped, so as to strengthen the sealing performance formed between the annular cover plate 3b and the annular wheel 3a, so as to make the centrifugal fan more efficient. Preferably, the width of the labyrinth channel 5 is approximately 0.5mm to 2mm.

[0032] During actual installation, a motor is arranged on one side of the volute 1, and the motor drives the rotating shaft 4 to rotate through a belt drive to drive the impeller 3 to operate, so that the wind enters the impeller 3 through the air guide ring 2 and is thrown out from the side of the impeller 3, and finally discharged through the air outlet 1a of the volute 1.

[0033] The annular cover plate 3b and the corresponding annular wheel disc 3a are clearance-matched through the retaining ring 3b1 and the convex ring 2a, so that the annular cover plate 3b and the annular wheel disc 3a can achieve a labyrinth seal without contact, effectively reducing air intake leakage, allowing the wind to completely enter the impeller 3 and be thrown out laterally, thereby improving the efficiency and performance of the centrifugal fan.

[0034] In this embodiment,

[0035] The air guide ring 2 is installed as follows: an annular sealing seat 2b is formed on the outer wall of the opposite end of the two air guide rings 2, and the sealing seat 2b is coaxially arranged with the air guide ring 2. The two sealing seats 2b are respectively pressed against the two end surfaces of the volute 1, and the sealing seat 2b is fixedly connected to the volute 1. Specifically, a circle of through holes 1 is horizontally penetrated on the sealing seat 2b, and the volute 1 is provided with threaded holes, the threaded holes and the through holes 1 are the same in number and the positions are one-to-one corresponding, and the sealing seat 2b is fixedly connected to the volute 1 by screws that pass through the through holes 1 and are screwed into the corresponding threaded holes through the rod.

[0036] The installation method of the rotating shaft 4 is as follows: the two air guide rings 2 are both provided with a connecting member 6, the connecting member 6 includes a ring body 6a sleeved on the rotating shaft 4 and a connecting strip 6b formed on the side wall of the ring body 6a, and the length of the connecting strip 6b extends radially along the ring body 6a, there are at least two connecting strips 6b and they are evenly spaced along the circumference of the ring body 6a, and one end of the connecting strip 6b is fixedly connected to the corresponding air guide ring 2, and both ends of the rotating shaft 4 are rotatably supported on the two ring bodies 6a through bearings 7. The above design is adopted to facilitate the support and positioning of the rotating shaft 4.

[0037] Among them, Figure 2 and Figure 3 As shown, the type of bearing 7 is a ball bearing, and the bearing 7 includes an inner ring 7a and an outer ring 7b, and the inner ring 7a and the outer ring 7b are respectively fixedly connected to the rotating shaft 4 and the corresponding ring body 6a by interference fit. Further explanation, the two connecting members 6 are symmetrically arranged, and an annular limiting seat 6a1 is formed on the inner wall of the ring body 6a, and two annular shoulders 4a are formed on the side wall of the rotating shaft 4. The adjacent ends of the two inner rings 7a are respectively pressed on the two annular shoulders 4a, and the opposite ends of the two outer rings 7b are respectively pressed on the two limiting seats 6a1. Under the cooperation of the two annular shoulders 4a and the two limiting seats 6a1, the two bearings 7 are effectively limited in the axial direction, which effectively ensures the stable rotation of the rotating shaft 4, so that the purpose of improving the performance of the centrifugal fan is stably achieved.

[0038] The connection strip 6b is installed as follows: the connection strip 6b is provided with two through holes for one of the screw rods to pass through, and the connection strip 6b is clamped and positioned between the corresponding sealing seat 2b and the corresponding screw head, that is, at this time, some screws are used to simultaneously position the connection piece 6 and the air guide ring 2, so as to simplify the structure and facilitate assembly. In this embodiment, each connection piece 6 includes four connection strips 6b, and the number of screws is greater than the number of connection strips 6b.

[0039] In actual products, an annular step 8 is formed between the inner wall of the convex ring 2a and the end face of the corresponding air guide ring 2, and the annular step 8 is coaxially arranged with the air guide ring 2 to form an avoidance, thereby reducing the amount of wind gathered in the maze channel 5.

[0040] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A centrifugal fan, comprising a volute (1) with two open ends and one side provided with an air outlet (1a), air guide rings (2) being fixed in both open ends, an impeller (3) and a rotating shaft (4) being arranged horizontally in the volute (1), the two ends of the rotating shaft (4) being rotatably supported on two air guide rings (2) respectively, the impeller (3) comprising an annular wheel disc (3a) sleeved and fixed on the rotating shaft (4) and annular cover plates (3b) arranged on both sides of the annular wheel disc (3a), a circle of blades (3c) being arranged between the two annular cover plates (3b) and the annular wheel disc (3a), characterized in that: A retaining ring (3b1) is integrally formed on the end surfaces of the two annular cover plates (3b) facing each other, and the retaining ring (3b1) is coaxially arranged with the annular cover plates (3b); a convex ring (2a) is correspondingly formed on the two air guide rings (2), and the two retaining rings (3b1) are respectively sleeved outside the two convex rings (2a); the retaining rings (3b1) and the convex rings (2a) at corresponding positions are gap-matched to form an annular labyrinth passage (5).

2. The centrifugal fan according to claim 1, characterized in that: The thickness of the retaining ring (3b1) is smaller than the size of the end face of the corresponding annular cover plate (3b), and the axial cross-section of the labyrinth channel (5) is substantially L-shaped.

3. The centrifugal fan according to claim 1 or 2, characterized in that: The width of the maze channel (5) is approximately 0.5 mm to 2 mm.

4. The centrifugal fan according to claim 1 or 2, characterized in that: An annular step (8) is formed between the inner wall of the convex ring (2a) and the end surface of the corresponding air guide ring (2).

5. The centrifugal fan according to claim 1, characterized in that: A connecting piece (6) is provided in each of the two air guide rings (2). The connecting piece (6) comprises a ring body (6a) sleeved on the rotating shaft (4) and a connecting strip (6b) formed on the side wall of the ring body (6a). The length of the connecting strip (6b) extends radially along the ring body (6a). There are at least two connecting strips (6b) which are evenly spaced along the circumference of the ring body (6a). One end of the connecting strip (6b) is fixedly connected to the corresponding air guide ring (2). Both ends of the rotating shaft (4) are rotatably supported on the two ring bodies (6a) via bearings (7).

6. The centrifugal fan according to claim 5, characterized in that: The bearing (7) comprises an inner ring (7a) and an outer ring (7b), and the inner ring (7a) and the outer ring (7b) are respectively fixedly connected to the rotating shaft (4) and the corresponding ring body (6a) by means of interference fit.

7. The centrifugal fan according to claim 6, characterized in that: The two connecting members (6) are symmetrically arranged, an annular limit seat (6a1) is formed on the inner wall of the ring body (6a), two annular stop shoulders (4a) are formed on the side wall of the rotating shaft (4), adjacent ends of the two inner rings (7a) are respectively pressed on the two annular stop shoulders (4a), and opposite ends of the two outer rings (7b) are respectively pressed on the two limit seats (6a1).

8. The centrifugal fan according to claim 5, characterized in that: An annular sealing seat (2b) is formed on the outer walls of the opposite ends of the two air guide rings (2). The two sealing seats (2b) are respectively pressed tightly against the two end surfaces of the volute (1), and the sealing seats (2b) are fixedly connected to the volute (1).

9. The centrifugal fan according to claim 8, characterized in that: A circle of through holes one is horizontally passed through the sealing seat (2b), and threaded holes are provided on the volute (1). The threaded holes and the through holes one are of the same number and have corresponding positions, and the sealing seat (2b) is fixedly connected to the volute (1) by screws through the through holes one and screwed into the corresponding threaded holes.

10. The centrifugal fan according to claim 9, characterized in that: The connecting strip (6b) is provided with two through holes for one of the screw rods to pass through, and the connecting strip (6b) is clamped and positioned between the corresponding sealing seat (2b) and the corresponding screw head.

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