Fan sealing structure and range hood comprising same

Abstract

The utility model provides a draught fan sealing structure and a range hood comprising the same, the draught fan sealing structure is used for sealing a gap between an air inlet ring and the edge of an impeller of a draught fan, the draught fan sealing structure comprises a sealing part, the sealing part is arranged on a volute front end cover of the draught fan in a surrounding mode, and the sealing part is used for sealing the gap between the air inlet ring and the edge of the impeller of the draught fan. And the sealing part extends into the arc-shaped opening of the air inlet ring from the edge of the impeller and seals a gap between the air inlet ring and the edge of the impeller. By arranging the sealing part, the gap between the air inlet ring and the edge of the impeller of the fan is effectively blocked, then secondary flow of the fan is reduced or eliminated, compared with an existing fan, the efficiency of the fan can be improved by 2-4 points under the condition of the same rotating speed, and the problem that the efficiency of the fan is not obviously improved due to the fact that the size of the fan is limited is solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to fan technical field, especially a fan sealing structure and contain its range hood. BACKGROUND

[0002] Multi-wing centrifugal fan is widely used in the power system of the range hood, and its characteristics are high static pressure and low noise. The aerodynamic efficiency of the forward multi-wing fan is generally 55%~58%, which is relatively low in the impeller machinery. In order to improve the aerodynamic efficiency, the blade parameters are usually optimized, the spiral shell profile design is matched, and the aerodynamic efficiency is optimized. Or the inlet and outlet pipe network resistance is optimized, and the aerodynamic efficiency of the operating point is improved. Due to the fact that the forward multi-wing fan is in a certain size space, the above-mentioned methods have a limit value for the aerodynamic efficiency, and it is difficult to further improve the aerodynamic efficiency.

[0003] And after investigation, there is also a "secondary flow" at the air inlet of the forward multi-wing fan. The "secondary flow" is another airflow that flows into the impeller from the air inlet, then flows through the inside of the spiral shell, and then flows out from the air outlet of the spiral shell. The existence of the "secondary flow" causes the efficiency loss of the fan, so in order to improve the aerodynamic efficiency, an optimized structure is needed to solve the "secondary flow". CONTENT OF THE UTILITY MODEL

[0004] The technical problem to be solved by the utility model is to overcome the defects of the "secondary flow" affecting the efficiency of the fan in the prior art, and to provide a fan sealing structure and a range hood comprising the same.

[0005] The utility model solves the above technical problems through the following technical scheme:

[0006] A fan sealing structure is used to seal the gap between the air inlet ring and the impeller edge of the fan, and the fan sealing structure comprises:

[0007] A sealing part is annularly arranged on the spiral shell front end cover of the fan, the sealing part extends from the impeller edge to the arc-shaped opening of the air inlet ring, and seals the gap between the air inlet ring and the impeller edge.

[0008] In the scheme, the sealing part is arranged to effectively block the gap between the air inlet ring and the impeller edge of the fan, thereby reducing or eliminating the "secondary flow" of the fan. Compared with the existing fan, the fan efficiency can be improved by 2~4 points under the same speed condition, and the problem of not obvious improvement of the fan efficiency caused by the limited size of the fan is overcome.

[0009] Preferably, the sealing part comprises:

[0010] A front-end ring of the impeller is arranged in the gap, a second end of the front-end ring is sealingly connected with the edge of the impeller, and a first end of the front-end ring extends towards the arc-shaped opening of the air inlet ring and forms a channel with the air inlet ring.

[0011] A sealing member is arranged in the arc-shaped opening of the air inlet ring, and the sealing member fills and seals the channel.

[0012] In the scheme, the front-end ring of the impeller is arranged at the edge of the impeller, so that the front-end ring of the impeller can rotate with the impeller, and the front-end ring of the impeller extends into the arc-shaped opening of the air inlet ring to form a channel with the air inlet ring. Compared with the gap, the size of the channel is smaller, that is, the size of the gap for the airflow to pass through is reduced. Further, the sealing member is arranged to seal the channel, thereby eliminating the secondary flow.

[0013] Preferably, the sealing member is provided with a sealing groove corresponding to the first end of the front-end ring of the impeller, the first end of the front-end ring of the impeller is inserted into the sealing groove, and the size of the first end of the front-end ring of the impeller is greater than the size of the sealing groove.

[0014] In the scheme, the first end of the front-end ring of the impeller is inserted into the sealing groove in a plug-in manner, which can reduce the occupation of the space inside the fan when the front-end ring of the impeller seals the gap with the sealing member, thereby improving the space utilization. The size of the first end of the front-end ring of the impeller is greater than the size of the sealing groove to form an interference fit, thereby preventing the airflow from forming a secondary flow.

[0015] Preferably, the first end of the front-end ring of the impeller has a terminal, the size of the terminal is greater than the size of the first end of the front-end ring of the impeller, and when the first end of the front-end ring of the impeller is inserted into the sealing groove, the terminal abuts against the inner wall of the sealing groove.

[0016] In the scheme, the terminal is arranged to effectively seal the sealing groove.

[0017] Preferably, the cross section of the terminal is a circular structure, and the radius of the terminal is in the range of 0.8-1 mm.

[0018] In the scheme, when the terminal is inserted into the sealing groove, the circular cross section of the terminal can abut against the groove bottom and the inner wall of the sealing groove, respectively, thereby achieving three abutments and improving the sealing performance. In addition, when the front-end ring of the impeller rotates with the impeller, the circular cross section of the terminal can reduce the friction with the inner wall and the groove bottom of the sealing groove compared with other structures.

[0019] Preferably, the first end and the second end of the front end ring of the impeller have a bending section therebetween, the radius of the bending section ranges from 1.2mm to 2.5mm, and the distance between the first end and the second end of the front end ring of the impeller ranges from 15.5mm to 16.5mm in the axial direction of the volute of the fan.

[0020] In the present scheme, the size of the front end ring of the impeller is limited by the above arrangement, thereby saving the internal space of the fan.

[0021] Preferably, the depth of the sealing groove ranges from 1mm to 2mm, and the width of the sealing groove ranges from 0.5mm to 1mm.

[0022] In the present scheme, the size of the sealing groove is limited by the above arrangement, thereby avoiding the difficulty of sealing caused by the excessively large size of the sealing groove.

[0023] Preferably, the sealing member further comprises an oil guide pipe, one end of the oil guide pipe is in communication with the volute of the fan, and the other end of the oil guide pipe is in communication with the sealing groove.

[0024] In the present scheme, the oil accumulated in the volute is reasonably utilized to seal the sealing groove, and the oil can also lubricate the first end of the front end ring of the impeller inserted into the sealing groove, thereby reducing the friction between the first end of the front end ring of the impeller and the inner wall and the bottom of the sealing groove when the front end ring of the impeller rotates with the impeller.

[0025] Preferably, a guide groove is formed in the volute front end cover of the fan corresponding to the oil guide pipe, and the oil guide pipe is in communication with the guide groove.

[0026] Preferably, the guide groove is located in the upper half region of the volute front end cover of the fan in the axial direction of the volute of the fan.

[0027] In the present scheme, the guide groove is arranged to enable the oil accumulated in the volute to flow into the oil guide pipe smoothly, and the guide groove is arranged in the upper half region, so that the oil can flow into the lower half region below when entering the sealing groove, thereby further reducing the processing cost and difficulty of arranging the guide groove on the volute front end cover.

[0028] An extractor hood, comprising the fan sealing structure as described above.

[0029] In the present scheme, the extractor hood comprises the fan sealing structure as described above, thereby improving the working efficiency of the fan of the extractor hood and eliminating the secondary flow, so that the efficiency of the extractor hood is improved by 2-4 points under the condition that the rotation speed, structure and occupied space remain unchanged.

[0030] The positive and progressive effects of this utility model are as follows: By setting a sealing part, this utility model can effectively block the gap between the air inlet ring and the impeller edge of the fan, thereby reducing or eliminating the "secondary flow" of the fan. Compared with existing fans, it can achieve a fan efficiency improvement of 2 to 4 percentage points under the same speed conditions, overcoming the problem of insignificant fan efficiency improvement caused by fan size limitations. Attached Figure Description

[0031] Figure 1 This diagram shows the positional relationship between the fan sealing structure and the impeller in a preferred embodiment of the present invention.

[0032] Figure 2 for Figure 1 A magnified view of part A in the image.

[0033] Figure 3 This is a schematic diagram of the structure of the impeller front end ring of a preferred embodiment of the present invention.

[0034] Figure 4 The oil guide groove and the front end cover of the volute are preferred embodiments of the present invention.

[0035] Figure 5 This is a fan efficiency curve of a preferred embodiment of the present invention.

[0036] Explanation of reference numerals in the attached figures:

[0037] Air inlet ring 1

[0038] Impeller edge 2

[0039] 3 front cover of the volute

[0040] 4 rear end caps of the volute

[0041] Gap 5

[0042] Bend section 6

[0043] Oil guide groove 7

[0044] Sealing part 10

[0045] Impeller front end ring 11

[0046] Terminal 111

[0047] Seal 12

[0048] Sealing groove 121 Detailed Implementation

[0049] The present invention will be described more clearly and completely below with reference to the accompanying drawings, using a preferred embodiment.

[0050] This embodiment provides a fan sealing structure, the specific structure of which is as follows: Figure 1 andFigure 2 As shown, the fan sealing structure is used to seal the gap 5 between the air inlet ring 1 and the impeller edge 2 of the fan. The fan sealing structure includes:

[0051] The sealing part 10 is arranged around the front end cover 3 of the volute of the fan. The sealing part 10 extends from the edge 2 of the impeller to the arc-shaped opening of the air inlet ring 1 and seals the gap 5 between the air inlet ring 1 and the edge 2 of the impeller.

[0052] Specifically, the fan casing includes an annular wall, a front cover 3, and a rear cover 4. An inlet ring 1 is mounted on the front cover 3, forming an inlet for air intake into the fan impeller. The inlet ring 1 is an arc-shaped plate with its arc-shaped opening facing the impeller to guide airflow into the inlet. A gap 5 is formed between the impeller edge 2 and the inlet ring 1. This gap 5 causes a "secondary flow" in the fan. Specifically, besides the airflow from the inlet into the impeller and out of the casing outlet, another stream flows from the inlet into the impeller, passes through the casing, and then re-enters the impeller through the gap 5 between the impeller edge 2 and the inlet ring 1. This "secondary flow" results in a loss of fan efficiency.

[0053] In this embodiment, to eliminate "secondary flow," a sealing part 10 is provided to effectively seal the gap 5 between the air inlet ring 1 and the impeller edge 2 of the fan, thereby reducing or eliminating the "secondary flow" of the fan. Figure 5 As shown, the dashed line represents the efficiency of a fan with a sealing structure, while the solid line represents the efficiency of a fan without a sealing structure. Compared to existing fans, fans with sealing structures can achieve an efficiency improvement of 2-4 percentage points under the same operating speed. Specifically, the operating efficiency of a fan without a sealing structure is generally 55%-58%, meaning its efficiency under extreme operating conditions is 55%-58%. Based on this, finite element analysis using existing technology shows that when the original fan efficiency is 55%, the operating efficiency of a fan with a sealing structure is 57%-59%. Similarly, when the original fan efficiency is 58%, the operating efficiency of a fan with a sealing structure is 60%-62%, thereby overcoming the problem of insignificant efficiency improvements caused by fan size limitations.

[0054] like Figure 3 As shown, in this embodiment, the sealing part 10 includes:

[0055] Impeller front end ring 11 is arranged in the gap 5. The second end of the impeller front end ring 11 is sealed to the impeller edge 2. The first end of the impeller front end ring 11 extends toward the arc-shaped opening of the air inlet ring 1 and forms a channel with the air inlet ring 1.

[0056] The sealing member 12 is arranged in the arc-shaped opening of the air inlet ring 1, and fills and seals the channel.

[0057] Specifically, the impeller front end ring 11 is annular, and is connected with the impeller and rotates with the impeller. Since the impeller front end ring 11 is annular, when the impeller rotates, the impeller front end ring 11 rotates with the impeller as a rotation, and does not occupy the internal space of the fan. The first end of the impeller front end ring 11 extends towards the air inlet ring 1 to form a channel with the air inlet ring 1. Compared with the gap 5, the channel has a smaller size, that is, the gap is reduced in size by the impeller front end ring 11, and further, the sealing member 12 is arranged to seal the channel, thereby eliminating the secondary flow.

[0058] The sealing member 12 can be sealing cotton in the prior art, and the material of the sealing cotton is EVA foam. Of course, in order to achieve the purpose of sealing the channel, other flexible materials in the prior art can also be used for sealing, which will not be described in detail here.

[0059] In other embodiments, only a baffle structure or a flexible filler can be arranged to seal the gap 5. The baffle structure can extend from the impeller edge 2 to the surface of the arc-shaped opening of the air inlet ring 1 to achieve sealing of the gap 5 in an abutting manner. Alternatively, a flexible filler such as rubber can be filled into the gap 5 to achieve the purpose of sealing the gap 5.

[0060] In this embodiment, the sealing member 12 is provided with a sealing groove 121 corresponding to the first end of the impeller front end ring 11, and the first end of the impeller front end ring 11 is inserted into the sealing groove 121 and the size of the first end of the impeller front end ring 11 is larger than the size of the sealing groove 121.

[0061] Specifically, the sealing member 12 is filled in the channel, and the sealing member 12 is pasted in the arc-shaped opening of the air inlet ring 1. The sealing member 12 is provided with a sealing groove 121 corresponding to the first end of the impeller front end ring 11, and the sealing groove 121 is used for inserting the first end of the impeller front end ring 11 to seal the channel in an inserting manner. Compared with the first end of the impeller front end ring 11 abutting on the outer surface of the sealing member 12, the size of the first end of the impeller front end ring 11 can be reduced when the impeller front end ring 11 and the sealing member 12 seal the gap, so as to improve the space utilization.

[0062] By setting the size of the first end of the impeller front end ring 11 to be larger than the size of the sealing groove 121, an interference fit is formed when the first end of the impeller front end ring 11 is inserted into the sealing groove 121, so as to prevent the airflow from forming a secondary flow again through the contact between the first end of the impeller front end ring 11 and the sealing groove 121.

[0063] Further, in the embodiment, the first end of the impeller front end ring 11 has a terminal 111, the size of the terminal 111 is greater than the size of the first end of the impeller front end ring 11, when the first end of the impeller front end ring 11 is inserted into the sealing groove 121, the terminal 111 abuts against the inner wall of the sealing groove 121.

[0064] Specifically, the size of the terminal 111 is greater than the size of the first end of the impeller front end ring 11, when the first end of the impeller front end ring 11 is inserted into the sealing groove 121, the terminal 111 extends into the sealing groove 121. By abutting against the inner wall of the sealing groove 121 through the terminal 111, the sealing performance of the sealing groove 121 is improved.

[0065] In the embodiment, the cross section of the terminal 111 is a circular structure, the radius of the terminal 111 ranges from 0.8mm to 1mm.

[0066] Specifically, from the perspective of Figure 2 and Figure 3 , the terminal 111 is a cylindrical structure, so that when the terminal 111 contacts the inner wall or the groove bottom of the sealing groove 121, the two sides of the terminal 111 can simultaneously abut against the inner wall of the sealing groove 121, achieving double abutment sealing. In addition, the cross section of the terminal 111 is a circular structure, so that after the terminal 111 extends into the sealing groove 121, the terminal 111 abuts against the groove bottom of the sealing groove 121, thereby achieving triple abutment and improving the sealing performance. In the embodiment, the radius of the terminal 111 is 0.85mm.

[0067] In addition, in the case where the impeller front end ring 11 rotates with the impeller, the cross section of the terminal 111 is a circular structure, and the three abutment surfaces of the inner wall and the groove bottom of the sealing groove 121 are arc surfaces, which can reduce the friction with the inner wall and the groove bottom of the sealing groove 121 compared to other shapes such as a conical structure or a rectangular structure.

[0068] In the embodiment, the first end and the second end of the impeller front end ring 11 have a bending section 6, the radius of the bending section 6 ranges from 1.2mm to 2.5mm, and the distance between the first end and the second end of the impeller front end ring 11 ranges from 15.5mm to 16.5mm along the axial direction of the volute of the fan.

[0069] Specifically, the cross section of the impeller front end ring 11 is an “L”-shaped structure, the bending section 6 is the corner of the “L”-shaped structure, the second end of the “L”-shaped structure is connected to the impeller, the first end of the “L”-shaped structure extends towards the arc-shaped opening of the air inlet ring 1, and the terminal 111 is arranged on the first end of the “L”-shaped structure. In the embodiment, the distance between the first end and the second end of the impeller front end ring 11 is 16mm, and the radius of the bending section 6 is 1.4mm. By limiting the size of the impeller front end ring 11, the internal space of the fan is saved, and the efficiency of the fan is not affected.

[0070] In the embodiment, the depth of the sealing groove 121 is 1-2 mm, and the width of the sealing groove 121 is 0.5-1 mm. Specifically, in the embodiment, the depth of the sealing groove 121 is 1.5 mm, and the width of the sealing groove 121 is 0.7 mm. By limiting the size of the sealing groove 121, the difficulty of sealing is increased.

[0071] In the embodiment, the distance between the surface of the sealing member 12 facing the impeller and the volute rear end cover 4 is less than the distance between the surface of the sealing member 12 facing the impeller and the volute front end cover 3, that is, the distance between the surface of the sealing member 12 facing the impeller and the impeller edge 2 is closer to the volute front end cover 3 than the distance between the volute front end cover 3 and the impeller edge 2, and the distance between the surface of the sealing member 12 facing the impeller and the volute front end cover 3 is 2.7 mm. By limiting the size of the distance between the two, the distance between the sealing member 12 and the impeller edge 2 is prevented from being too close to affect the normal rotation of the impeller.

[0072] In the embodiment, the sealing member 12 further comprises an oil guide pipe (not shown in the figure), one end of the oil guide pipe being in communication with the volute of the fan, and the other end of the oil guide pipe being in communication with the sealing groove 121.

[0073] Specifically, the oil guide pipe is arranged in the sealing member 12 and is used to guide the oil accumulated in the volute into the sealing groove 121. The oil guide pipe can be a pipe or a groove in communication with the volute and the sealing groove 121, so as to reasonably utilize the oil accumulated in the volute for the oil sealing of the sealing groove 121. At the same time, the oil can also lubricate the first end of the impeller front ring inserted into the sealing groove 121 and the terminal 111, so that when the terminal 111 rubs against the inner wall and the bottom of the sealing groove 121 while the impeller front ring 11 rotates with the impeller, the outer surface of the terminal 111 is lubricated by the oil, thereby reducing the friction between the first end of the impeller front ring 11 and the inner wall and the bottom of the sealing groove 121 compared with the impeller front ring 11 without the lubricating structure.

[0074] As shown in Figure 4 In the embodiment, the volute front end cover 3 of the fan is provided with an oil guide groove 7 corresponding to the oil guide pipe.

[0075] Specifically, the volute front end cover 3 is provided with the oil guide groove 7 on the side surface facing the sealing member 12, and the oil guide groove 7 is used to supply oil to the oil guide pipe, thereby reasonably utilizing the oil accumulated in the volute to the sealing member 12. The oil guide groove 7 is a circular ring groove.

[0076] Further, the oil guide groove 7 is located in the upper half region of the volute front end cover 3 of the fan in the axial direction of the volute of the fan.

[0077] Specifically, the fan's axial direction is divided into an upper and lower region, with the fan's axis as the dividing line. The upper region is a fan with a 180° fan-shaped structure, and the lower region is also a fan with a 180° fan-shaped structure. This describes the location of the upper region. An oil guide groove 7 is provided in the upper region. That is, the oil guide groove 7 is a 180° fan-shaped groove located in the upper region of the fan. Due to the fluidity of oil, by only providing the oil guide groove 7 in the upper region, when oil enters the sealing groove 121, it can be guided to the seal 12 located in the lower region by its own flow. The sealing groove 121 of the seal 12 in the lower region can also allow grease to flow in. Compared to having the oil guide groove 7 ring around the front cover 3 of the volute, its processing cost and difficulty are further reduced.

[0078] This embodiment also provides a range hood, which includes the aforementioned fan sealing structure. This range hood, including the aforementioned fan sealing structure, improves the fan efficiency and eliminates "secondary flow," thereby increasing the range hood efficiency by 2-4 percentage points while maintaining the same speed, structure, and space requirements.

[0079] While specific embodiments of this utility model have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this utility model is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this utility model, but all such changes and modifications fall within the scope of protection of this utility model.

Claims

1. A fan seal structure for sealing a gap between an inlet ring and an impeller edge of a fan, characterized by, The fan sealing structure comprises: A sealing part is annularly arranged on the front end cover of the volute of the fan, extends from the impeller edge to the arc-shaped opening of the air inlet ring, and seals the gap between the air inlet ring and the impeller edge.

2. The fan seal structure of claim 1, wherein The sealing part comprises: An impeller front end ring is annularly arranged in the gap, the second end of the impeller front end ring is sealingly connected with the impeller edge, the first end of the impeller front end ring extends towards the arc-shaped opening of the air inlet ring and forms a channel with the air inlet ring; A sealing member is arranged in the arc-shaped opening of the air inlet ring, and the sealing member fills and seals the channel.

3. The fan seal structure of claim 2, wherein The sealing member is provided with a sealing groove corresponding to the first end of the impeller front end ring, the first end of the impeller front end ring is inserted into the sealing groove, and the size of the first end of the impeller front end ring is greater than the size of the sealing groove.

4. The fan seal construction of claim 3, wherein, The first end of the impeller front end ring has a terminal, the size of the terminal is greater than the size of the first end of the impeller front end ring, and when the first end of the impeller front end ring is inserted into the sealing groove, the terminal abuts against the inner wall of the sealing groove.

5. The fan seal structure of claim 4, wherein The cross section of the terminal is a circular structure, and the radius of the terminal is in the range of 0.8-1mm.

6. The fan seal construction of claim 2, wherein, The first end and the second end of the impeller front end ring have a bending section therebetween, the radius of the bending section is in the range of 1.2-2.5mm, and the distance between the first end and the second end of the impeller front end ring in the axial direction of the volute is in the range of 15.5-16.5mm.

7. The fan seal construction of claim 3 wherein, The depth of the sealing groove is 1-2mm, and the width of the sealing groove is 0.5-1mm.

8. The fan seal construction of claim 3 wherein, The sealing member further comprises an oil guide pipe, one end of the oil guide pipe is in communication with the volute of the fan, and the other end of the oil guide pipe is in communication with the sealing groove.

9. The fan seal construction of claim 8, wherein, The front end cover of the volute of the fan is provided with an oil guide groove corresponding to the oil guide pipe, and the oil guide pipe is in communication with the oil guide groove; And / or the oil guide groove is located in the upper half region of the front end cover of the volute of the fan in the axial direction of the volute of the fan.

10. A range hood characterized by, The range hood comprises the fan sealing structure according to any one of claims 1-9.

Images