Impeller assembly and mixing apparatus

Abstract

The present application discloses an impeller assembly and a mixing apparatus, and relates to the technical field of solid and liquid mixing devices. The impeller assembly includes an impeller structure and a housing structure. The impeller structure includes a body, and a surface of the body is provided with a plurality of backward-skewed blades. A blade angle of each backward-skewed blade on any flow plane first decreases progressively and then increases progressively from an inlet to an outlet. A first baffle is disposed on a lower portion of the body. The housing structure includes a second baffle. The first baffle is provided with first guide slots, and the second baffle is provided with second guide slots. A fluid enters from the inlet at an upper portion of the body, flows along the surface of the body, and flows out through the outlet at a lower portion of the body and through the first guide slots and the second guide slots. A centerline of each first guide slot is deflected towards a direction opposite to a rotation direction of the impeller structure, and a centerline of each second guide slot is deflected towards the rotation direction of the impeller structure. The present application solves the problems of unstable discharge, large vibration and noise, and insufficient work efficiency.

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority of Chinese patent application No. 202111190681.9, filed with the Chinese Patent Office on October 13, 2021 and entitled "Impeller Assembly and Mixing Apparatus".TECHNICAL FIELD

[0002] The present application relates to the technical field of solid and liquid mixing devices, in particular to an impeller assembly and a mixing apparatus.BACKGROUND

[0003] In the related art, there is no special design on the blade type of blades on an inner side and flow paths of a fluid. The blades have limited ability to do work on the fluid, and multiple layers of baffles greatly hinder the movement of the fluid, making it difficult for discharge, so the fluid needs to be accelerated and discharged by using the work done by discharge blades on an outer side of the baffles. However, the forced acceleration and discharge of the fluid by the discharge blades will lead to large pressure fluctuations in a discharge chamber, thereby causing pulsations in the discharge flow, generating large noise and vibration, and reducing the work efficiency of a dispersion apparatus.

[0004] RU2208472C1 relates to an apparatus. The apparatus is designed for production of finely divided emulsions, suspensions, saturated solutions, homogeneous mixtures (mayonnaises, ketchups, various fruit and vegetable pastes, apple butter, jams made of whole fruits, doughs prepared from whole grains, meat and fish pastes, feeds for animals, etc. ) with preliminary grinding of treated product directly in apparatus and sterilization init. Invention may be used in chemical, oil producing, wood-pulp and paper industries, agriculture and in other industries. Apparatus consists of rotor installed on rotating shaft and accommodated blades and shell with slots; coaxial stator secured on body between rotor blades and rotor shell and having trapezoidal diametrical cross-section and slots. Expanding outside stator slots are made at angle of 70-90 deg. to diameter, directed towards rotor rotation and inclined inside through angle of 10-15 deg. and having cogs on internal surface. Rotor slots expanding outside are made at angle of 15-45 deg. to diameter and directed opposite to shell motion and are inclined outside through angle equaling angle of stator slot inclination. For attaining of preliminary grinding of material, rotor blades may be made extending above rotor inlet hole, bent towards motion and have sharp inlet edge. To preclude formation of funnel-shaped vortexes in flow and to clean rotor blades, installed in front of them with clearance of less than 1 mm and secured to body are immovable plates arranged along flow, and knives rotating together with rotor and installed above said plates with clearance of not in excess of 1 mm on rotor extending shaft. This document discloses an impeller assembly according to the preamble of appended claim 1.

[0005] US6783271B1 relates to a rotary dispergator. The rotary dispergator comprises a rotor 4 set on a shaft 5 of a stator 2 having a coaxial row of teeth 7 and an outer concentric row of straightening blades 8, encompassing the rotor 4 from the outside, the width of radial cuts between the straightening blades 8 of the stator 2 being several times smaller than their length. The rotor 4 has an impeller comprised of straight or curved blades 10, as well as a coaxial row of blades 11. A method of producing food products consists in that with the help of the dispergator a mechano-acoustic effect with an intensity of 100-500 W / kg of product is produced on the material to be comminuted placed into a container. With the use of rotary dispergator, various food products based on a vegetable material are produced: a soybean paste, a mayonnaise.

[0006] RU2033252C1 relates to a rotor apparatus. The rotor apparatus has housing, inlet and outlet branch pipes, rotor, and stator. Passages are made in the rotor over periphery. The axes of the passages are inclined and bent counter to the direction of rotation of the rotor. Walls are made up as resonators.

[0007] EP2609999A1 relates to a mixing and dispersing device. The mixing and dispersing device is provided with ante-mixing rotary vanes 130 and post-mixing rotary vanes 150. The ante-mixing rotary vanes 130 are rotatably arranged in a fluidity material side area E1 and send fluidity material drawn from a radial inside thereof to a first-stage mixing area E3 being radially outside of a partition plate 120 and induce powder material in a powder side area E2 to the first-stage mixing area E3. The post-mixing rotary vanes 150 are arranged in a second-stage mixing area E4 that is on a downstream side of the first-stage mixing area E3 and that differs from the first-stage mixing area E3 in an axial direction, and disperse mixed material of the fluidity material and the powder material flowing from the first-stage mixing area E3 to the second-stage mixing area E4 to send out the mixed material to a discharge port 113 being radially outside thereof.

[0008] FR 2 446 667 A1 discloses an impeller assembly using straight blades and nested stator and rotor baffles.SUMMARY OF THE INVENTION

[0009] The invention is defined by the independent claim. An object of the present application is to provide an impeller assembly and a mixing apparatus to solve the above-mentioned problems of the prior art, thus solving the problems of unstable discharge, large vibration and noise, and insufficient work efficiency that are liable to occur in a dispersion apparatus using a centrifugal discharge method when the viscosity of a solid-liquid mixture is large.

[0010] To achieve the above object, the present application provides the following technical solution: The present invention as defined in appended claim 1 provides an impeller assembly, including an impeller structure and a housing structure that are rotatable relative to each other, wherein the impeller structure includes a body, a surface of the body is provided with a plurality of backward-skewed blades distributed circumferentially around the body, at least one layer of first baffle is provided on a lower portion of the body, and the first baffle is arranged on an outer side of the backward-skewed blades; the housing structure includes at least one layer of second baffle which is located on an inner side and / or an outer side of the first baffle; the first baffle is provided with a plurality of first guide slots, and the second baffle is provided with a plurality of second guide slots; the impeller structure and the housing structure are configured to allow a fluid to enter from an inlet at an upper portion of the body, flow along the surface of the body, and flow out through an outlet at a lower portion of the body and through the first guide slots and the second guide slots; and a centerline of each first guide slot is deflected towards a direction opposite to a rotation direction of the impeller structure, and a centerline of each second guide slot is deflected towards the rotation direction of the impeller structure, and wherein the housing structure comprises two layers of second baffles which are located on both an inner side and an outer side of the first baffle respectively, wherein the two layers of second baffles are nested and buckled to surround the first baffle.

[0011] In an embodiment of the present invention, the size of the body increases progressively from the upper portion of the body to the lower portion of the body, and the surface of the body is a curved surface.

[0012] In an embodiment of the present invention, a blade angle of each backward-skewed blade on any flow plane first decreases progressively and then increases progressively from the inlet to the outlet, the blade angle being an included angle between a tangent line of a surface arc line of the backward-skewed blade and an axial plane of the impeller structure.

[0013] In an embodiment of the present invention, the magnitude of the blade angle at the inlet is 20-80°, and the magnitude of the blade angle at the outlet is 0-30°.

[0014] In an embodiment of the present invention, an included angle between the centerline of each first guide slot and a radial direction of a central axis of the body is 15-50°.

[0015] In an embodiment of the present invention, an included angle between the centerline of each second guide slot and a radial direction of a central axis of the body is 35-80°.

[0016] The present application also provides a mixing apparatus including the impeller assembly. Compared with the prior art, the present application has the following technical effects: The present application uses the backward-skewed blade that when rotating, can be better coupled with rotation of fluid flow, so that the backward-skewed blade provided on the body does work on the fluid more efficiently. In particular, it is found by simulation calculations that by designing the blade angle of each backward-skewed blade on any flow plane to first decrease progressively and then increase progressively from the inlet to the outlet, the backward-skewed blade can do work on the fluid more efficiently. On the other hand, the first guide slots are formed on the first baffle, and the second guide slots are formed on the second baffle, and a kinetic energy loss generated when the fluid passes through the first baffle and the second baffle is reduced by the directions of the first guide slots and the second guide slots. After dispersed in a dispersion area between the first baffle and the second baffle, the fluid still has sufficient kinetic energy to be discharged in a centrifugal way, without the need to add discharge blades for doing work on the fluid. This greatly reduces disturbance to the fluid in a discharge area, so that the fluid pressure in the discharge area can remain uniform and stable, and the fluid can be discharged at a stable flow rate, thus eliminating vibration and noise caused by pulsation.BRIEF DESCRIPTION OF THE DRAWINGS

[0017] To describe technical solutions in embodiments of the present invention or in the prior art more clearly, a brief introduction to the drawings for use in embodiments will be given below. Obviously, the drawings described below are only some embodiments in the present invention, and for those of ordinary skill in the art, other drawings may also be obtained based on these drawings without creative work. Fig. 1 is a schematic diagram of an impeller assembly in the present application; Fig. 2 is a sectional view along A-A in Fig. 1; Fig. 3 is a partial enlarged view at I in Fig. 2; Fig. 4 is a schematic diagram of an impeller assembly in the present application; and Fig. 5 is a schematic diagram of a housing structure in the present application.

[0018] Reference numerals: 100 - impeller assembly, 1 - impeller structure, 2 - housing structure, 3 - body, 4 - backward-skewed blade, 5 - first baffle, 6 - second baffle, 7 - first guide slot, 8 - second guide slot.DETAILED DESCRIPTION

[0019] Technical solutions in embodiments of the present invention will be described below clearly and completely in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all the embodiments. All other embodiments obtained by those of ordinary skill in the art without creative work, based on the embodiments in the present invention, may fall into the protection scope of the present invention defined by the appended claims.

[0020] An object of the present invention is to provide an impeller assembly and a mixing apparatus to solve the above-mentioned problems of the prior art, thus solving the problems of unstable discharge, large vibration and noise, and insufficient work efficiency that are liable to occur in a dispersion apparatus using a centrifugal discharge method when the viscosity of a solid-liquid mixture is large.

[0021] To make the above object, features and advantages of the present invention more obvious and understandable, the present application will be described further in detail below in conjunction with the accompanying drawings and specific implementations.Embodiment 1

[0022] As shown in Figs. 1 to 5, this embodiment provides an impeller assembly 100, including an impeller structure 1 and a housing structure 2 that are rotatable relative to each other. The impeller structure 1 includes a body 3. A surface of the body 3 is provided with a plurality of backward-skewed blades 4 distributed circumferentially around the body 3. At least one layer of first baffle 5 is provided on a lower portion of the body 3, and the first baffle 5 is arranged on an outer side of the backward-skewed blades 4. The housing structure 2 includes two layers of second baffle 6. The second baffle 6 is located on an inner side and an outer side of the first baffle 5. According to the invention, the housing structure 2 is provided with an inner layer and an outer layer of second baffle 6, on an inner side and arranged on an outer side of the first baffle 5, respectively, and the second baffle 6 is nested and buckled at an outer periphery of the first baffle 5. The first baffle 5 is circumferentially provided with a plurality of first guide slots 7, and the first guide slots 7 are uniformly distributed on the first baffle 5. The second baffles 6 on the inner side and the outer side are circumferentially provided with a plurality of second guide slots 8, respectively, and the second guide slots 8 are uniformly distributed on the second baffles 6. The cross-sectional shapes of the first guide slots 7 and the second guide slots 8 are similar to rhombuses, and deflected directions of the first guide slots 7 and deflected directions of the second guide slots 8 are arranged alternately. The impeller assembly 100 is provided with an inlet of a fluid at an upper end of the body 3 of the impeller structure 1, and like an outlet of the fluid at a lower end of the body 3 of the impeller structure 1. The fluid enters from the inlet at an upper portion of the body 3, flows along the surface of the body 3, and flows out successively through the outlet at a lower portion of the body 3, the second guide slots 8 on the inner side, the first guide slots 7, and the second guide slots 8 on the outer side. A centerline of each first guide slot 7 is deflected towards a direction opposite to a rotation direction of the impeller structure 1, and a centerline of each second guide slot 8 is deflected towards the rotation direction of the impeller structure 1.

[0023] In this embodiment, using a placement direction of Fig. 2 as a reference, the impeller structure 1 rotates around an axis of the body 3 in a clockwise direction.

[0024] In this embodiment, the size of the body 3 increases progressively from the upper portion of the body 3 to the lower portion of the body 3 such that the body 3 forms a truncated cone, and the surface of the body 3 is a curved surface. A meridional flow path line of the body 3 from the inlet to the outlet is a quasi-arc curve that is bent inwardly.

[0025] In this embodiment, a blade angle of each backward-skewed blade 4 on any flow plane first decreases progressively and then increases progressively from the inlet to the outlet. The blade angle is an included angle between a tangent line of a surface arc line of the backward-skewed blade 4 and an axial plane of the impeller structure 1, and takes a positive value.

[0026] In this embodiment, a gap between the backward-skewed blade 4 and the housing changes continuously and smoothly from the inlet to the outlet.

[0027] In this embodiment, the magnitude of the blade angle at the inlet is 20-80°, and the magnitude of the blade angle at the outlet is 0-30°, and the magnitude of the smallest blade angle is 0-30°. The angle distribution of the blade angle is related to the aerodynamic load distribution of the backward-skewed blade 4. Based on a simulation result of the fluid in the backward-skewed blade 4, the angle distribution of the blade angle is adjusted to achieve better coupling between the fluid and the backward-skewed blade 4 after the fluid flows therethrough to ensure that the backward-skewed blade 4 does work on the fluid efficiently.

[0028] In this embodiment, an included angle (i.e., β 2 ) between the centerline of each first guide slot 7 and a radial direction of a central axis of the body 3 is 15-50°, and an included angle (i.e., B 1 and β 3 ) between the centerline of each second guide slot 8 and the radial direction of the central axis of the body 3 is 35-80°. Specifically referring to Fig. 3, β 1 is an angle between a centerline L1 of a second guide slot 8 on the inner side and a radial line R1, β 2 is an angle between a centerline L2 of a first guide slot 7 and a radial line R2, and β 3 is an angle between a centerline L3 of a second guide slot 8 on the outer side and a radial line R3. The radial line R1, the radial line R2 and the radial line R3 are all lines along a radius direction starting from the central axis of the body 3. A point of intersection between the centerline L1 of the second guide slot 8 of the second baffle 6 on the inner layer and the radial line R1 is located on the circumference where an inner wall of the second baffle 6 on the inner layer is located, a point of intersection between the centerline L2 of the first guide slot 7 and the radial line R2 is located on the circumference where an inner wall of the first baffle 5 is located, and a point of intersection between the centerline L3 of the second guide slot 8 of the second baffle 6 on the outer side and the radial line R3 is located on the circumference where an inner wall of the second baffle 6 on the outer layer is located.

[0029] The rotation direction of the impeller assembly 100 is denoted by an arrow in Fig. 3. In this embodiment, on the one hand, the blade angle is adjusted to control the fluid load distribution of the backward-skewed blade 4, and the blade angle distribution achieves better coupling between rotation of the backward-skewed blade 4 and fluid flow, so that the backward-skewed blade 4 provided on the body 3 does work on the fluid more efficiently; on the other hand, the first guide slots 7 are formed on the first baffle 5, and the second guide slots 8 are formed on the second baffle 6, and a kinetic energy loss generated when the fluid passes through the first baffle 5 and the second baffle 6 is reduced by the directions of the first guide slots 7 and the second guide slots 8. Specifically, the second baffle 6 fixed to the housing structure 2 is stationary, and the centerline of each second guide slot 8 is deflected towards the rotation direction of the impeller structure 1, which allows the fluid to pass through the second guide slot 8 smoothly without changing its direction greatly. The first baffle 5 fixed to the impeller structure 1 rotates together with the impeller structure 1, such that its remaining portion except for the first guide slots 7 can be regarded as an extension of the backward-skewed blade 4, and the first guide slots 7 can also made into a backward-skewed structure, which is more conducive to doing work on the fluid.

[0030] After dispersed in a dispersion area between the first baffle 5 and the second baffle 6, the fluid still has sufficient kinetic energy to be discharged in a centrifugal way, without the need to add discharge blades for doing work on the fluid on the outer side of the outermost second baffle 6. This greatly reduces disturbance to the fluid in a discharge area, so that the fluid pressure in the discharge area can remain uniform and stable, and the fluid can be discharged at a stable flow rate, thus eliminating vibration and noise caused by pulsation.Embodiment 2

[0031] This embodiment provides a mixing apparatus including the impeller assembly 100 of Embodiment 1.

Claims

1. An impeller assembly (100), comprising an impeller structure (1) and a housing structure (2) that are rotatable relative to each other, wherein the impeller structure (1) comprises a body (3), a surface of the body (3) is provided with a plurality of backward-skewed blades (4) distributed circumferentially around the body (3), at least one layer of first baffle (5) is provided on a lower portion of the body (3), and the first baffle (5) is arranged on an outer side of the backward-skewed blades (4); the housing structure (2) comprises at least one layer of second baffle (6) which is located on an inner side and / or an outer side of the first baffle (5); the first baffle (5) is circumferentially provided with a plurality of first uniformly distributed guide slots (7), and the second baffle (6) is circumferentially provided with a plurality of second uniformly distributed guide slots (8); the impeller structure (1) and the housing structure (2) are configured to allow a fluid to enter from an inlet at an upper portion of the body (3), flow along the surface of the body (3), and flow out through an outlet at a lower portion of the body (3) and through the first guide slots (7) and the second guide slots (8); and a centerline of each first guide slot (7) is deflected towards a direction opposite to a rotation direction of the impeller structure (1), and a centerline of each second guide slot (8) is deflected towards the rotation direction of the impeller structure (1), characterised in that the housing structure (2) comprises two layers of second baffles (6), which are located on both an inner side and an outer side of the first baffle (5) respectively, wherein the two layers of second baffles (6) are nested and buckled to surround the first baffle (5).

2. The impeller assembly (100) according to claim 1, wherein the size of the body (3) increases progressively from the upper portion of the body (3) to the lower portion of the body (3), and the surface of the body (3) is a curved surface.

3. The impeller assembly (100) according to claim 1, wherein a blade angle of each backward-skewed blade (4) on any flow plane first decreases progressively and then increases progressively from the inlet to the outlet, the blade angle being an included angle between a tangent line of a surface arc line of the backward-skewed blade (4) and an axial plane of the impeller structure (1).

4. The impeller assembly (100) according to claim 3, wherein the magnitude of the blade angle at the inlet is 20-80°, and the magnitude of the blade angle at the outlet is 0-30°.

5. The impeller assembly (100) according to claim 1, wherein an included angle between the centerline of each first guide slot (7) and a radial direction of a central axis of the body (3) is 15-50°.

6. The impeller assembly (100) according to claim 1, wherein an included angle between the centerline of each second guide slot (8) and a radial direction of a central axis of the body (3) is 35-80°.

7. A mixing apparatus, comprising the impeller assembly (100) of any one of claims 1 to 6.

Images