Wing type centrifugal impeller

Abstract

The utility model relates to the technical field of ventilation equipment, in particular to a wing type impeller for a centrifugal fan. The wing type centrifugal impeller comprises an impeller cover, blades, a rear disc and a shaft sleeve, the impeller cover, the blades and the rear disc are welded into a whole, the shaft sleeve is fixedly connected with the rear disc through rivets, the impeller cover is in an arc shape, and the inner side edge and the outer side edge of the impeller cover are turned by 90-degree angle steel edges to be reinforced. Through reasonable design and manufacturing process matching, the wing type centrifugal impeller is simple in overall structure and accurate in size and shape, the manufacturing process is convenient to operate, impurities in the wing type hollow blades can be effectively removed, the efficiency of the fan impeller is improved, and the operation noise of the fan impeller is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of ventilation equipment, and more specifically to an airfoil-shaped impeller for a centrifugal fan. Background Art

[0002] As we all know, the impellers with airfoil-shaped blades in centrifugal fans are famous for their high efficiency and low noise. The common manufacturing process is to stamp thin iron plates into airfoil-shaped hollow blades, and then weld them with the front and rear discs of the impeller. In order to ensure the accuracy of the fan impeller size, it is necessary to configure special molds, process fixtures, stamping equipment, etc. for various types of fan blades and impellers; the manufacturing difficulty and cost are relatively high, and the shape and size accuracy of the impeller and the appearance quality are difficult to guarantee.

[0003] In addition, during the welding process of the wing-shaped hollow blades and the front and rear discs of the impeller, welding slag is often generated on the hollow inner side of the blades due to the characteristics of the welding process, and impurities such as scale are generated on the steel surface during the heat treatment of the impeller after welding. At present, the industry generally adopts the method of drilling process holes on the wing blades to remove welding impurities, and then welding to fill the process holes. This manufacturing method is time-consuming and has high manufacturing costs; and the impurity removal effect is not ideal, resulting in unfavorable conditions such as reduced aerodynamic efficiency and increased noise performance of the centrifugal fan. Utility Model Content

[0004] In view of the shortcomings of the prior art, the utility model provides an airfoil-shaped centrifugal impeller, which can effectively solve the welding impurities of the airfoil-shaped hollow blades, accurately position the blades, shorten the manufacturing cycle, and improve the manufacturing accuracy and operating efficiency. The specific scheme is as follows:

[0005] A wing-shaped centrifugal impeller comprises a wheel cover, blades, a rear disc and a shaft sleeve. The wheel cover, blades and rear disc are welded together, the shaft sleeve is connected and fixed to the rear disc by rivets, the wheel cover is arc-shaped, and the inner and outer edges are reinforced with 90-degree angle steel edges.

[0006] The blade is a hollow wing centrifugal blade, and the blade comprises a windward blade, a leeward blade and a reinforcing rib plate, and a plurality of reinforcing rib plates are arranged between the windward blade and the leeward blade.

[0007] The rear disc is cut with a plurality of blade installation positioning holes according to the lower cross section of the blade.

[0008] The blades penetrate the rear disk and are exposed to the side of the rear disk plate by a dimension of 0.02-0.03D, where D is the diameter of the impeller; and the blades penetrate the rear disk so that the inner side of the blades communicate with the outside through the installation positioning hole of the rear disk.

[0009] The angle θ between the vertical plane of the blade and the plane of the rear disc is designed to be between 95° and 100°.

[0010] The outer diameter of the blade and the distance L from the outer diameter of the rear disc are designed to be between 0.065 and 0.075D, where D is the impeller diameter.

[0011] The processing technology of the blades is as follows: the windward blades and leeward blades are formed by stamping after laser cutting, and a plurality of positioning and connecting slot holes for blade reinforcement plates are opened on the windward blades and leeward blades; there are multiple reinforcement plates between the windward blades and leeward blades, and the blades are connected into one by plug welding technology.

[0012] The stamping forming is a secondary die-stamping forming, that is, an annealing treatment is performed after the first blade stamping forming, and then a blade stamping forming is performed again after the annealing treatment.

[0013] The utility model realizes the overall structure of the airfoil-shaped centrifugal impeller to be simple, the size and shape are precise, the manufacturing process is convenient to operate through reasonable design and manufacturing process coordination, and can effectively clear impurities inside the airfoil-shaped hollow blades, improve the efficiency of the fan impeller, and reduce the operating noise of the fan impeller. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a structural schematic diagram of an airfoil-type centrifugal impeller of the utility model;

[0015] Figure 2 This is a schematic diagram of the blade structure of an airfoil-type centrifugal impeller of the utility model;

[0016] Figure 3 This is a schematic diagram of the structure of the rear disc of a wing-shaped centrifugal impeller of the utility model;

[0017] The numbers are as follows: 1. wheel cover; 2. blades; 3. rear disc; 4. shaft sleeve; 5. induced draft blades; 6. blade reinforcement ribs; 7. leeward blades; 8. blade installation positioning holes. DETAILED DESCRIPTION

[0018] like Figure 1 , Figure 2 , Figure 3 As shown, the utility model is an airfoil type centrifugal impeller and processing technology, including a wheel cover 1, blades 2, a rear disc 3, a shaft sleeve 4 and other components. The wheel cover 1, blades 2, and rear disc 3 are welded together, and the shaft sleeve is connected and fixed to the rear disc 3 by rivets.

[0019] The wheel cover 1 is arc-shaped, with 90-degree angle steel edges on the inner and outer edges for reinforcement. It is formed by die spinning, and has a smooth and streamlined surface. The angle steel of the wheel cover 1 has both a reinforcing effect and forms a primary labyrinth seal with the collector air inlet. Together with the inserted gap of the impeller, it prevents internal leakage of the fan and increases the air volume of the fan due to internal leakage by about 5%.

[0020] The blade 2 is a hollow wing centrifugal blade, which is formed by welding and assembling the windward blade 5, the leeward blade 7, the reinforcing rib plate 6 and other components. The windward blade 5 and the leeward blade 7 are both formed by stamping after laser cutting, and multiple blade reinforcing plate positioning and connection slot holes are opened on the windward blade 5 and the leeward blade 7 according to the design requirements; there are multiple blade reinforcing ribs 6 between the two blades, and the blades are connected into one by plug welding technology.

[0021] The rear disc 3 is cut with a plurality of blade installation positioning holes 8 according to the airfoil profile of the lower section of the blade. The blade 2 penetrates the rear disc 3 and exposes the side dimension A≈0.02~0.03D of the rear disc plate (D is the impeller diameter, the smaller value of D is 0.03 and the larger value of D is 0.02).

[0022] As a further technical solution: the blade 2 is welded to the rear disc 3, and the angle θ between the vertical surface of the blade 2 and the plane of the rear disc 3 is designed to be between 95° and 100°; the outer diameter of the blade D1≈(0.065~0.075)D (D is the impeller diameter (mm)). The distance L between the outer diameter of the blade B and the outer diameter of the rear disc 3 is between (0.065~0.075)D (D is the impeller diameter (mm)). This angle θ can effectively solve the problem of the impeller's epidermis falling off due to oxidation of the inner steel plate surface of the blade at the end of its service life, and it is naturally discharged from the inner surface of the blade under the centrifugal force and gravity of the fan operation instead of existing on the inner side of the blade. This value of L not only strengthens the strength of the impeller's rear disc, but also improves the impeller's aerodynamic efficiency as a bladeless rotary diffuser.

[0023] As a further technical solution: the blades (including the windward blades 5 and the leeward blades 7) are stamped and formed by secondary molding, that is, annealing is performed after the first blade stamping, and then the blades are stamped and formed again after annealing. This can eliminate the stress generated during the cold stamping of the blades, improve the strength of the blades and ensure the forming size of the blades.

[0024] As a further technical solution: the rear disc 3 is cut with a blade installation positioning hole 8, and the blade 2 is inserted into the rear disc 3, so that the inner side of the airfoil-shaped hollow blade 2 is connected to the outside through the profile hole 8 on the rear disc surface, which can realize the complete cleaning of the inner welding slag caused by improper welding during the assembly welding of the blade 2 with the wheel cover 1 and the rear disc 3, as well as the oxide scale and other impurities on the surface of the steel during the heat treatment after the impeller welding, so as to ensure the impurity-free manufacturing process inside the airfoil-shaped hollow blade 2.

[0025] The above is only a preferred embodiment of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A wing-shaped centrifugal impeller, characterized in that: It includes a wheel cover, blades, a rear disc and a shaft sleeve. The wheel cover, blades and rear disc are welded together. The shaft sleeve is connected and fixed to the rear disc by rivets. The wheel cover is arc-shaped, and the inner and outer edges are reinforced with 90-degree angle steel edges. The blades are hollow wing centrifugal blades. The blades include windward blades, leeward blades and reinforcing ribs. There are multiple reinforcing ribs between the windward blades and the leeward blades. The rear disc is cut with multiple blade installation positioning holes according to the lower cross-section of the blades.

2. The airfoil-shaped centrifugal impeller according to claim 1, characterized in that: The blades penetrate the rear disk and are exposed to the side of the rear disk plate by a dimension of 0.02-0.03D, where D is the diameter of the impeller; and the blades penetrate the rear disk so that the inner side of the blades communicate with the outside through the installation positioning hole of the rear disk.

3. The airfoil-shaped centrifugal impeller according to claim 2, characterized in that: The angle θ between the vertical plane of the blade and the plane of the rear disk is designed to be between 95° and 100°; the outer circle size of the blade and the outer diameter distance L of the rear disk are designed to be between 0.065 and 0.075D, where D is the impeller diameter.

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