Pressure screen driven by permanent magnet synchronous motor

Abstract

The utility model relates to the technical field of pressure screen equipment, in particular to a permanent magnet synchronous motor driven pressure screen which comprises a machine shell fixedly arranged on a base, a permanent magnet synchronous motor with an upward motor shaft is arranged in the machine shell, and the top of the machine shell is detachably connected with a machine cover; the permanent magnet synchronous motor is fixedly arranged on the bottom plate, and the periphery of the bottom plate is fixedly connected with the base through a connecting shell. A motor shaft of the permanent magnet synchronous motor is fixedly sleeved with a rotor core, the rotor core is fixedly connected with a rotor wing, and rotor wing blades are fixedly arranged below the rotor wing; a screen cylinder is arranged between the rotor blade and the permanent magnet synchronous motor, one end of the screen cylinder is fixedly connected with a front end cover of the permanent magnet synchronous motor, and the other end is fixedly connected with the base; the pressure screen driven by the permanent magnet synchronous motor is simple in structure, small in occupied area and convenient to disassemble and assemble.

Description

Technical Field

[0001] The present application relates to the technical field of pressure screen equipment, and in particular to a pressure screen driven by a permanent magnet synchronous motor. Background Art

[0002] The statements in this section merely provide background technical information related to the present application and do not necessarily constitute prior art.

[0003] Permanent magnet synchronous motors have simple structures, high reliability, and high power factor. In recent years, they have been increasingly used in various industries. As the main equipment in the papermaking screening process, the pressure screen has become a trend in the pulping and screening industry in recent years to use permanent magnet synchronous motors to achieve high efficiency and energy saving. In the prior art, the conventional pressure screen motor installation method is to install a special motor frame on one side of the pressure screen, connected by pulleys and belts. This connection method has the disadvantages of low transmission efficiency and large space occupation. Another installation method is to set the permanent magnet motor at the bottom of the pressure screen and drive the pressure screen by direct drive, but it still occupies a large area and is inconvenient to disassemble and assemble. There is also a method in the prior art to build the permanent magnet synchronous motor into the pressure screen. Since the motor is installed inside the pressure screen, it occupies a small area, but it is easy to cause the permanent magnet synchronous motor to heat up, and the permanent magnet synchronous motor is easy to resonate during the flow of pulp, causing the installation to become loose.

[0004] In view of this, it is necessary to provide a pressure screen driven by a permanent magnet synchronous motor to solve the above technical problems. Utility Model Content

[0005] Based on this, in order to solve the above technical problems, the present application provides a pressure screen driven by a permanent magnet synchronous motor.

[0006] The technical solution adopted by this application to solve the problems existing in the prior art is:

[0007] The present application proposes a pressure screen driven by a permanent magnet synchronous motor, comprising a casing fixed on a base, a permanent magnet synchronous motor with a motor shaft facing upwards arranged in the casing, and a cover detachably connected to the top of the casing;

[0008] The permanent magnet synchronous motor is fixedly mounted on the bottom plate, and the bottom plate is fixedly connected to the base via a connecting shell around the bottom plate;

[0009] A rotor core is fixedly mounted on the motor shaft of the permanent magnet synchronous motor, a rotor is fixedly connected to the rotor core, and rotor blades are fixedly arranged below the rotor;

[0010] A sieve drum is provided between the rotor blades and the permanent magnet synchronous motor, one end of the sieve drum is fixedly connected to the front end cover of the permanent magnet synchronous motor, and the other end of the sieve drum is fixedly connected to the base;

[0011] An inlet is arranged on the upper side of the casing, and a slurry outlet is arranged on the connecting shell.

[0012] Preferably, a flow guide device is provided outside the permanent magnet synchronous motor.

[0013] Preferably, the guide device is a spiral guide strip fixedly arranged on the outer surface of the permanent magnet synchronous motor.

[0014] Preferably, the flow guide device is a flow guide piece fixedly sleeved on the outside of the permanent magnet synchronous motor, and the flow guide piece comprises a cylinder, and a spiral flow guide strip is fixedly provided on the outside of the cylinder;

[0015] The inner surface of the cylinder is fitted and connected with the outer surface of the permanent magnet synchronous motor;

[0016] A fixing flange is fixedly arranged at the bottom of the cylinder, and a plurality of mounting holes are opened on the fixing flange; the mounting holes are used to fix the cylinder to the bottom plate by bolts.

[0017] Preferably, the cylinder is made of stainless steel.

[0018] Preferably, a connecting piece is fixedly provided on the base, the housing is fixedly provided above the middle of the connecting piece, and one end of the inner side of the connecting piece is fixedly connected to the connecting housing.

[0019] Preferably, a plurality of guide teeth are fixedly provided on the outer side of the rotor blade.

[0020] Preferably, the permanent magnet synchronous motor is electrically connected to an external power supply;

[0021] A slag outlet which can be opened and closed is arranged below the casing.

[0022] Preferably, the junction box of the permanent magnet synchronous motor is fixedly arranged below the base plate.

[0023] Compared with the prior art, the beneficial effects of this application are:

[0024] 1. A pressure screen driven by a permanent magnet synchronous motor in the present application has a simple structure, occupies a small area, and is easy to disassemble and assemble.

[0025] 2. The design of spiral guide strips reduces the impact of slurry on the permanent magnet synchronous motor, ensuring stable installation of the permanent magnet synchronous motor; at the same time, the contact area between the permanent magnet synchronous motor and the slurry is increased, ensuring the heat dissipation of the permanent magnet synchronous motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings in the specification, which constitute a part of the present application, are used to provide further understanding of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute improper limitations on the present application.

[0027] Figure 1This is a schematic diagram of the overall structure of a pressure screen driven by a permanent magnet synchronous motor in this application.

[0028] Figure 2 is a schematic diagram of the overall structure of a flow guide device in an embodiment,

[0029] Figure 3 Schematic diagram of the overall structure of the spiral guide strip in one embodiment.

[0030] In the figure:

[0031] 1. Inlet, 2. Machine cover, 3. Machine casing, 4. Base, 5. Connecting shell, 6. Slurry outlet, 7. Bottom plate, 8. Permanent magnet synchronous motor, 9. Rotor, 10. Rotor blades, 11. Screen drum, 12. Rotor core, 13. Connector, 14. Guide teeth, 15. Spiral guide strips, 16. Cylinder, 17. Fixing flange, 18. Mounting hole. DETAILED DESCRIPTION

[0032] The present application is further described below in conjunction with the accompanying drawings and embodiments.

[0033] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0034] In the present disclosure, terms such as "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "side", "bottom" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. They are relational words determined only for the convenience of describing the structural relationships of the various parts or elements of the present disclosure, and do not specifically refer to any part or element in the present disclosure and should not be understood as limitations on the present disclosure.

[0035] The reason why a permanent magnet synchronous motor driven pressure screen in the present application adopts a permanent magnet synchronous motor instead of a three-phase asynchronous motor is that: the output speeds of three-phase asynchronous motors with 2 poles, 4 poles, 6 poles, 8 poles and 10 poles are 3000prm, 1500prm, 1000prm, 750prm and 600prm respectively (without considering the slip rate). This speed is not suitable for the pressure screen, and the higher the number of poles, the lower the power factor. The speed required for the pressure screen is basically between 120-500rpm even for pressure screens of different specifications. Permanent magnet synchronous motors can be designed with low speed and high torque, almost any speed, and have a higher power factor. The permanent magnet synchronous motor mentioned in this application should be called low-speed and high-torque permanent magnet synchronous motor, referred to as "permanent magnet motor"

[0036] Figure 1 It is a preferred embodiment of a permanent magnet synchronous motor driven pressure screen of the present application. As can be seen from the figure, a permanent magnet synchronous motor driven pressure screen of the present application includes a casing 3 fixedly mounted on a base 4, a permanent magnet synchronous motor 8 with a motor shaft facing upward is arranged in the casing 3, and a cover 2 is detachably connected to the top of the casing 3; the permanent magnet synchronous motor 8 is fixedly mounted on a bottom plate 7, and the bottom plate 7 is fixedly connected to the base 4 through a connecting shell 5 on all sides; a rotor core 12 is fixedly mounted on the motor shaft of the permanent magnet synchronous motor 8, and a rotor is fixedly connected to the rotor core 12 9, a rotor blade 10 is fixedly provided below the rotor 9; a mechanical seal is built into the motor shaft of the motor, a screen drum 11 is provided between the rotor blade 10 and the permanent magnet synchronous motor 8, one end of the screen drum 11 is fixedly connected to the front end cover of the permanent magnet synchronous motor 8, and the other end is fixedly connected to the base 4; an inlet 1 is provided on the upper side of the casing 3, the inlet 1 is a slurry inlet, and is connected to the slurry pipeline that has not been screened by the pressure screen, the connecting shell 5 is designed in a bowl shape, and a slurry outlet 6 is provided on the connecting shell 5, and the slurry outlet 6 is connected to the pipeline for conveying the screened slurry. The permanent magnet synchronous motor 8 is electrically connected to an external power supply, and the rotation of the permanent magnet synchronous motor 8 is controlled by the external power supply. The junction box of the permanent magnet synchronous motor 8 is located below the bottom plate 7; a slag outlet that can be opened and closed is provided below the casing 3, and the waste slag can be discharged by opening the slag outlet.

[0037] In some embodiments, a connecting member 13 is fixedly provided on the base 4 , the housing 3 is fixedly provided above the middle of the connecting member 13 , and one inner end of the connecting member 13 is fixedly connected to the connecting shell 5 .

[0038] In some embodiments, a plurality of guide teeth 14 are fixedly provided on the outer side of the rotor blade 10, and the function of the guide teeth 14 is to better achieve stirring of the slurry.

[0039] There is also a method of building a permanent magnet synchronous motor inside the pressure screen in the prior art. Since the motor is installed inside the pressure screen, it occupies a small area, but it is easy to cause the permanent magnet synchronous motor to heat up, and the permanent magnet synchronous motor is easy to resonate during the flow of slurry, causing the installation to loosen. For this reason:

[0040] In some embodiments, the permanent magnet synchronous motor 8 is provided with a flow guide device on the outside. In one embodiment, the flow guide device is a spiral flow guide bar 15 fixedly arranged on the outer surface of the permanent magnet synchronous motor 8. In this case, the shell of the permanent magnet synchronous motor 8 needs to be reprocessed or customized; Figure 3 The structure is a spiral guide strip 15. When the rotor 9 rotates, the slurry in the casing 3 rotates, and the slurry itself contacts the outer surface of the permanent magnet synchronous motor 8, which plays a role in dissipating the heat of the permanent magnet synchronous motor 8. At the same time, the slurry is guided to the slurry outlet 6 under the action of the spiral guide strip 15, which greatly reduces the scouring of the permanent magnet synchronous motor 8 as a whole by the slurry, and avoids the problem of loose installation caused by resonance of the permanent magnet synchronous motor during the flow of the slurry.

[0041] However, the above-mentioned flow guide device requires customization or modification of the permanent magnet synchronous motor 8. In order to further increase the convenience of use, in some embodiments, the flow guide device is a flow guide piece fixedly mounted on the outside of the permanent magnet synchronous motor 8, and the flow guide piece includes a cylinder 16, and a spiral guide strip 15 is fixedly provided on the outside of the cylinder 16. The temperature of the permanent magnet synchronous motor 8 is conducted to the spiral guide strip 15 through the cylinder 16, and then conducted to the slurry by the spiral guide strip 15 to achieve heat dissipation of the permanent magnet synchronous motor 8; the inner surface of the cylinder 16 is fittedly connected to the outer surface of the permanent magnet synchronous motor 8; a fixing flange 17 is fixedly provided at the bottom of the cylinder 16, and a plurality of mounting holes 18 are opened on the fixing flange 17; the mounting holes 18 are used to fix the cylinder 16 to the base plate 7 by bolts.

[0042] In some embodiments, the barrel 16 is made of stainless steel.

[0043] The pressure screen driven by a permanent magnet synchronous motor of the present application has a simple structure, small footprint, and is easy to disassemble and assemble. The design of the spiral guide strip reduces the impact of the slurry on the permanent magnet synchronous motor, ensuring the stable installation of the permanent magnet synchronous motor; at the same time, the contact area between the permanent magnet synchronous motor and the slurry is increased, ensuring the heat dissipation of the permanent magnet synchronous motor.

[0044] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0045] Although the above describes the specific implementation methods of the present application in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present application. Technical personnel in the relevant field should understand that on the basis of the technical solution of the present application, various modifications or deformations that can be made by technical personnel in this field without creative work are still within the scope of protection of the present application.

Claims

1. A pressure screen driven by a permanent magnet synchronous motor, characterized in that: It comprises a casing (3) fixed on a base (4), a permanent magnet synchronous motor (8) with the motor shaft facing upward is arranged in the casing (3), and a cover (2) is detachably connected to the top of the casing (3); The permanent magnet synchronous motor (8) is fixedly mounted on the bottom plate (7), and the bottom plate (7) is fixedly connected to the base (4) via a connecting shell (5) on all sides; A rotor core (12) is fixedly mounted on the motor shaft of the permanent magnet synchronous motor (8), a rotor (9) is fixedly connected to the rotor core (12), and a rotor blade (10) is fixedly disposed below the rotor (9); A sieve drum (11) is provided between the rotor blade (10) and the permanent magnet synchronous motor (8), one end of the sieve drum (11) is fixedly connected to the front end cover of the permanent magnet synchronous motor (8), and the other end of the sieve drum (11) is fixedly connected to the base (4); An inlet (1) is provided on the upper side of the casing (3), and a slurry outlet (6) is provided on the connecting casing (5).

2. A pressure screen driven by a permanent magnet synchronous motor according to claim 1, characterized in that: A flow guide device is provided outside the permanent magnet synchronous motor (8).

3. A permanent magnet synchronous motor driven pressure screen according to claim 2, characterized in that: The flow guide device is a spiral flow guide strip (15) fixedly arranged on the outer surface of the permanent magnet synchronous motor (8).

4. A permanent magnet synchronous motor driven pressure screen according to claim 2, characterized in that: The flow guide device is a flow guide piece fixedly sleeved on the outside of the permanent magnet synchronous motor (8), the flow guide piece comprising a cylinder (16), and a spiral flow guide strip (15) is fixedly arranged on the outside of the cylinder (16); The inner surface of the cylinder (16) is fitted and connected to the outer surface of the permanent magnet synchronous motor (8); A fixing flange (17) is fixedly provided at the bottom of the cylinder (16), and a plurality of mounting holes (18) are opened on the fixing flange (17); the mounting holes (18) are used to fix the cylinder (16) on the bottom plate (7) by means of bolts.

5. A permanent magnet synchronous motor driven pressure screen according to claim 4, characterized in that: The material of the cylinder (16) is stainless steel.

6. A permanent magnet synchronous motor driven pressure screen according to claim 1, characterized in that: A connecting piece (13) is fixedly provided on the base (4), the housing (3) is fixedly provided above the middle of the connecting piece (13), and one end of the inner side of the connecting piece (13) is fixedly connected to the connecting housing (5).

7. A permanent magnet synchronous motor driven pressure screen according to claim 1, characterized in that: A plurality of guide teeth (14) are fixedly provided on the outer side of the rotor blade (10).

8. The pressure screen driven by a permanent magnet synchronous motor according to claim 1, characterized in that: The permanent magnet synchronous motor (8) is electrically connected to an external power supply; A slag outlet which can be opened and closed is provided below the casing (3).

9. The pressure screen driven by a permanent magnet synchronous motor according to claim 1, characterized in that: The terminal box of the permanent magnet synchronous motor (8) is fixedly arranged below the bottom plate (7).

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