A centrifugal blower capable of preventing blade tip leakage

Abstract

The present invention relates to the field of blowers, and in particular to a centrifugal blower capable of preventing blade tip leakage. The blower comprises a motor housing, a motor shaft, a bearing device, a blast impeller and a volute; the volute is provided with a blast channel, and the blast impeller is located in the blast channel; the blast impeller is provided with an impeller body, blast blades and guide vanes; a blade tip gap is provided between the blast blades and the inner wall of the blast channel, and one end of the blade tip gap is connected to the air outlet end of the blast channel; the guide vane is provided at the air inlet end of the impeller body, the guide vane is used to pressurize the air flowing through, and the air pressure after the guide vane pressurizes is greater than or equal to the air pressure at the air outlet end of the blast channel; a guide vane gap is provided between the guide vane and the inner wall of the blast channel, and the two ends of the guide vane gap are respectively connected to the air inlet end of the blast channel and the other end of the blade tip gap. The blower ensures the blast flow rate of the blower and improves the stability and service life of the entire equipment.

Description

Technical Field

[0001] The invention relates to the field of blowers, and in particular to a centrifugal blower capable of preventing blade tip leakage. 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. Centrifugal fans are widely used in ventilation, dust removal and cooling of factories, mines, tunnels, cooling towers, vehicles, ships and buildings; ventilation and air intake of boilers and industrial furnaces; cooling and ventilation in air conditioning equipment and household appliances; drying and selection of grains; wind tunnel wind source and inflation and propulsion of hovercraft, etc.

[0003] like Figure 1 , Figure 2 As shown, after the gas passes through the blower impeller and does work, it enters the outlet end of the volute blast channel, and a part of the gas will leak along the top of the blast blade to the inlet end of the blast channel of the volute; the blower in the prior art is provided with an axial seal c between the inner wall of the blast channel inlet end of the volute a and the inlet end of the blower impeller b to throttle and seal the gas leaking to the top of the blast blade b, so as to reduce the influence of the axial force.

[0004] The existing technology has the following shortcomings: the axial seal cannot completely throttle the gas, and some high-pressure gas will still leak to the air inlet end of the blower channel, thereby reducing the blower flow rate of the blower; at the same time, this part of the high-pressure gas will produce a large axial force on the volute, thereby causing the axial force of the entire machine to be unstable, reducing the stability and service life of the entire equipment. Summary of the invention

[0005] The purpose of the present invention is: to address the above-mentioned problem, it is proposed to set a guide vane for pressurizing the gas at the air inlet end of the blower impeller, and a guide vane gap which is respectively connected to the blade tip gap and the air inlet end of the blower channel is set between the guide vane and the inner wall of the blower channel; thereby, the gas at the air inlet end of the blower channel is pressurized and guided to the blade tip gap, and the gas at the air outlet end of the blower channel is prevented from leaking to the air inlet end of the blower channel, thereby ensuring the blower flow rate of the blower; at the same time, the two streams of gas flowing in opposite directions can offset a part of the axial force, thereby avoiding the instability of the axial force of the whole machine, and improving the stability and service life of the whole equipment to provide a centrifugal blower that can prevent blade tip leakage.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0007] A centrifugal blower capable of preventing blade tip leakage, the blower comprises a motor housing, a motor shaft, a bearing device, a blast impeller and a volute; the bearing device is sleeved on the outer wall of the motor shaft, and the blast impeller is fixed at one end of the motor shaft; the volute is provided with a blast channel, and the blast impeller is located in the blast channel; the blast impeller is provided with an impeller body, blast blades and guide vanes; a blade tip gap is provided between the blast blades and the inner wall of the blast channel, and one end of the blade tip gap is connected to the air outlet end of the blast channel; the guide vane is provided at the air inlet end of the impeller body, the guide vane is used to pressurize the air flowing through, and the air pressure after the guide vane pressurizes is greater than or equal to the air pressure at the air outlet end of the blast channel; a guide vane gap is provided between the guide vane and the inner wall of the blast channel, and the guide vane gap comprises a radial guide vane gap and an axial guide vane gap; the lower end of the radial guide vane gap is connected to the air inlet end of the blast channel, and the upper end of the radial guide vane gap is connected to the other end of the blade tip gap through the axial guide vane gap.

[0008] Preferably, the guide vane is of an inclined shape with a short distance from the air inlet end to the center of the blower impeller and a long distance from the air outlet end to the center of the blower impeller.

[0009] Preferably, the bearing device comprises a front bearing and a rear bearing, both of which are fixed on the motor housing, and the front bearing and the rear bearing are respectively sleeved on both ends of the motor shaft.

[0010] Preferably, a sealing block is provided between the back of the blower impeller and the motor housing, and the sealing block is used to prevent the high-pressure gas in the volute from entering the interior of the blower along the back of the blower impeller.

[0011] Preferably, a fairing is fixedly provided at the air inlet end of the blower impeller, and the fairing is used to guide the inhaled air to improve the blowing efficiency of the blower.

[0012] Preferably, a frequency converter is arranged outside the motor barrel, the frequency converter is provided with a frequency converter housing, and the frequency converter housing is provided with heat dissipation ribs.

[0013] Preferably, a heat insulation board made of composite material is provided between the frequency converter and the motor barrel, and the heat insulation board is used to reduce heat transfer between the blower and the frequency converter.

[0014] Preferably, the blower is further provided with a fan fixing seat, on which a heat dissipation fan is provided, and the heat dissipation fan is used to dissipate heat from the inside of the blower and the inverter.

[0015] Preferably, the heat dissipation fan comprises a fan motor and axial flow blades, and an output end of the fan motor is connected to the axial flow blades.

[0016] The centrifugal blower that can prevent blade tip leakage by adopting the above technical solution has the following advantages:

[0017] The rotation of the motor shaft drives the blower impeller to rotate, and then drives the guide vanes to rotate to pressurize the gas at the air inlet end of the blast channel; the pressurized gas then flows along the guide vane gap to the blade top gap; since the air pressure after the guide vane pressurization is greater than or equal to the air pressure at the air outlet end of the blast channel, the pressurized gas can prevent the gas at the air outlet end of the blast channel from leaking to the air inlet end of the blast channel, thereby ensuring the blast flow rate of the blower; at the same time, the pressurized gas and the leaked gas at the air outlet end of the blast channel flow in opposite directions to offset a part of the axial force, thereby avoiding axial force instability of the entire machine and improving the stability and service life of the entire equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of a blower impeller in the prior art.

[0019] Figure 2 It is a partial enlarged structural schematic diagram of the blower impeller in the prior art.

[0020] Figure 3 It is a schematic diagram of the structure of the present invention.

[0021] Figure 4-6 Schematic diagram of the structure of the blower impeller. DETAILED DESCRIPTION

[0022] The specific implementation modes of the present invention are described in detail below with reference to the accompanying drawings.

[0023] Example 1

[0024] like Figure 3-6A centrifugal blower capable of preventing blade tip leakage is shown, the blower comprises a motor housing 1, a motor shaft 2, a bearing device 3, a blast impeller 4 and a volute 5; the bearing device 3 is sleeved on the outer wall of the motor shaft 2, and the blast impeller 4 is fixed to one end of the motor shaft 2; the volute 5 is provided with a blast channel 51, and the blast impeller 4 is located in the blast channel 51; the blast impeller 4 is provided with an impeller body 41, blast blades 42 and guide blades 43; a blade tip gap 44 is provided between the blast blade 42 and the inner wall of the blast channel 51, and one end of the blade tip gap 44 is connected to the air outlet end of the blast channel 51 The guide vane 43 is arranged at the air inlet end of the impeller body 41, and the guide vane 43 is used to pressurize the air flowing through, and the air pressure after the guide vane 43 pressurizes is greater than or equal to the air pressure at the air outlet end of the blast channel 51; a guide vane gap 45 is arranged between the guide vane 43 and the inner wall of the blast channel 51, and the guide vane gap 45 includes a radial guide vane gap 451 and an axial guide vane gap 452; the lower end of the radial guide vane gap 451 is connected to the air inlet end of the blast channel 51, and the upper end of the radial guide vane gap 451 is connected to the other end of the blade tip gap 44 through the axial guide vane gap 452. In this manner, the motor shaft 2 rotates and thereby drives the blower impeller 4 to rotate, and then drives the guide vanes 43 to rotate to pressurize the gas at the air inlet end of the blast channel 51; the pressurized gas then flows along the guide vane gap to the blade top gap; since the air pressure after pressurization by the guide vanes 43 is greater than or equal to the air pressure at the air outlet end of the blast channel 51, the pressurized gas can prevent the gas at the air outlet end of the blast channel 51 from leaking to the air inlet end of the blast channel 51, thereby ensuring the blast flow rate of the blower; at the same time, the pressurized gas and the leaked gas at the air outlet end of the blast channel 51 flow in opposite directions to offset a portion of the axial force, thereby avoiding axial force instability of the entire machine and improving the stability and service life of the entire equipment.

[0025] The guide vane 43 is in an inclined shape with a short distance from the air inlet end to the center of the blower impeller 4 and a long distance from the air outlet end to the center of the blower impeller 4 so as to pressurize the air flowing therethrough.

[0026] like Figure 3 As shown, the bearing device 3 includes a front bearing 31 and a rear bearing 32 , both of which are fixed on the motor housing 1 , and the front bearing 31 and the rear bearing 32 are respectively sleeved on both ends of the motor shaft 2 to support the motor shaft 2 .

[0027] A sealing block 52 is provided between the back of the impeller 4 and the motor housing 1 , and the sealing block 52 is used to prevent the high-pressure gas in the volute 5 from entering into the blower along the back of the impeller 4 .

[0028] A fairing 46 is fixedly provided at the air inlet end of the blower impeller 4, and the fairing 46 is used to guide the inhaled air to improve the blowing efficiency of the blower.

[0029] A frequency converter 11 is disposed outside the motor barrel 1 , the frequency converter 11 is provided with a frequency converter housing 12 , and the frequency converter housing 12 is provided with heat dissipation ribs 13 .

[0030] A composite heat insulation board 14 is provided between the inverter 11 and the motor barrel 1, and the heat insulation board 14 is used to reduce the heat transfer between the blower and the inverter 11. The heat dissipation ribs 13 provided on the inverter housing 12 can effectively reduce the temperature of the inverter 11 and increase the life of the inverter 11.

[0031] The blower is also provided with a fan fixing seat 15, on which a cooling fan 16 is provided, which is used to dissipate heat inside the blower and the frequency converter 11. The cooling fan 16 includes a fan motor and axial flow blades, and the output end of the fan motor is connected to the axial flow blades to effectively increase the cooling air volume.

Claims

1. A centrifugal blower capable of preventing blade tip leakage, characterized in that: The blower comprises a motor housing (1), a motor shaft (2), a bearing device (3), a blast impeller (4) and a volute (5); the bearing device (3) is sleeved on the outer wall of the motor shaft (2), and the blast impeller (4) is fixed to one end of the motor shaft (2); the volute (5) is provided with a blast passage (51), and the blast impeller (4) is located in the blast passage (51); the blast impeller (4) is provided with an impeller body (41), blast blades (42) and guide blades (43); A blade tip gap (44) is provided between the blast blade (42) and the inner wall of the blast channel (51), and one end of the blade tip gap (44) is connected to the air outlet end of the blast channel (51); the guide blade (43) is in an inclined shape with a short distance between the air inlet end and the center of the blast impeller (4) and a long distance between the air outlet end and the center of the blast impeller (4); the guide blade (43) is provided at the air inlet end of the impeller body (41); the guide blade (43) is used to pressurize the air flowing through; and the air pressure after the guide blade (43) pressurizes is greater than the air pressure at the air outlet end of the blast channel (51). A guide vane gap (45) is provided between the guide vane (43) and the inner wall of the blast channel (51), and the guide vane gap (45) includes a radial guide vane gap (451) and an axial guide vane gap (452); the lower end of the radial guide vane gap (451) is connected to the air inlet end of the blast channel (51), and the upper end of the radial guide vane gap (451) is connected to the other end of the blade tip gap (44) through the axial guide vane gap (452); and a portion of the axial guide vane gap (452) that decreases from upstream to downstream along the axial direction is provided at one end close to the radial guide vane gap (451).

2. A centrifugal blower capable of preventing blade tip leakage according to claim 1, characterized in that: The bearing device (3) comprises a front bearing (31) and a rear bearing (32); the front bearing (31) and the rear bearing (32) are both fixed on the motor housing (1), and the front bearing (31) and the rear bearing (32) are respectively sleeved on both ends of the motor shaft (2).

3. A centrifugal blower capable of preventing blade tip leakage according to claim 1, characterized in that: A sealing block (52) is provided between the back of the impeller (4) and the motor housing (1), and the sealing block (52) is used to prevent high-pressure gas in the volute (5) from entering the interior of the blower along the back of the impeller (4).

4. A centrifugal blower capable of preventing blade tip leakage according to claim 1, characterized in that: A fairing (46) is fixedly arranged at the air inlet end of the blower impeller (4), and the fairing (46) is used to guide the inhaled air to improve the blowing efficiency of the blower.

5. A centrifugal blower capable of preventing blade tip leakage according to claim 1, characterized in that: A frequency converter (11) is arranged outside the motor cylinder (1), the frequency converter (11) is provided with a frequency converter housing (12), and the frequency converter housing (12) is provided with heat dissipation ribs (13).

6. A centrifugal blower capable of preventing blade tip leakage according to claim 5, characterized in that: A heat insulation board (14) made of a composite material is provided between the frequency converter (11) and the motor cylinder (1), and the heat insulation board (14) is used to reduce heat transfer between the blower and the frequency converter (11).

7. A centrifugal blower capable of preventing blade tip leakage according to claim 5, characterized in that: The blower is also provided with a fan fixing seat (15), and a heat dissipation fan (16) is provided on the fan fixing seat (15). The heat dissipation fan (16) is used to dissipate heat from the inside of the blower and the frequency converter (11).

8. A centrifugal blower capable of preventing blade tip leakage according to claim 7, characterized in that: The heat dissipation fan (16) comprises a fan motor and axial flow blades, and an output end of the fan motor is connected to the axial flow blades.

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