Impeller main shaft connecting structure and mounting method

Abstract

The invention relates to the technical field of impeller machinery, in particular to an impeller main shaft connecting structure and a mounting method. Comprising a main shaft, a bidirectional thread fastening screw and an impeller, the impeller is provided with a triangular prism molded surface, an impeller large end and an impeller small end, an inner hexagonal hole is formed in the end, close to the impeller, of the bidirectional thread fastening screw, and the axis of the inner hexagonal hole is consistent with that of a through hole; the mounting method comprises the following steps of: positively rotating the bidirectional thread fastening screw on the main shaft; the impeller is arranged at one end of the two-way thread fastening screw in a sleeving mode, and the impeller is rotated reversely till the triangular prism molded surface makes contact with the molded surface of the main shaft; the bidirectional thread fastening screw is driven to rotationally penetrate into the threaded hole of the main shaft until the left side end part of the impeller is propped against the main shaft; continuously rotating the inner hexagonal flower-shaped wrench in the forward direction until the tightening torque reaches a required value; in this way, it is guaranteed that the diameter of the two-way thread fastening screw is large, meanwhile, the diameter of the small end of the impeller is as small as possible, and connection reliability and aerodynamic efficiency are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of impeller machinery, and in particular to an impeller main shaft connection structure and an installation method. Background Art

[0002] The impellers of centrifugal compressors and centrifugal expanders are usually processed separately from the main shaft and connected through a transmission structure. The current transmission structure includes: end face teeth, profiles or end face friction, and then screws are inserted from the small end of the impeller to apply a certain pulling force to tighten the impeller on the main shaft. The screw tension is designed to ensure that the impeller overcomes the aerodynamic axial force while its transmission structure transmits torque reliably. When the tension is determined, it is hoped that the screw diameter is as large as possible and the strength is more reliable.

[0003] The traditional connection structure composed of the above-mentioned transmission structure and screws will result in a larger screw head size, which will lead to an increase in the hub diameter of the small end of the impeller, affecting the aerodynamic efficiency. Summary of the invention

[0004] The purpose of the present invention is to provide an impeller-spindle connection structure and an installation method, aiming to solve the technical problem that the traditional connection structure composed of a transmission structure and a screw in the prior art will produce a large screw head size, thereby increasing the diameter of the impeller small end hub and affecting the aerodynamic efficiency.

[0005] To achieve the above-mentioned purpose, the present invention adopts an impeller-spindle connection structure, including a spindle, a bidirectional threaded fastening screw and an impeller, the impeller having a triangular prism profile, an impeller big end and an impeller small end, the impeller is sleeved on the outer side wall of the spindle, and the triangular prism profile and the impeller big end are respectively in contact with the spindle, the bidirectional threaded fastening screw has a forward thread and a reverse thread, the two ends of the bidirectional threaded fastening screw are respectively inserted into the spindle and the impeller, the forward thread cooperates with the spindle, and the reverse thread cooperates with the impeller, the bidirectional threaded fastening screw has a hexagonal hole at one end close to the impeller, and a through hole is provided at the impeller small end, and the hexagonal hole is consistent with the axial centerline of the through hole.

[0006] The present invention also provides an impeller main shaft installation method, comprising the following steps: Rotate the bidirectional threaded fastening screw in a positive direction and screw it onto the main shaft; Sleeve the impeller onto one end of the bidirectional threaded fastening screw, fix the bidirectional threaded fastening screw with a hexagonal wrench, and rotate the impeller in the opposite direction until the triangular prism profile contacts the profile of the main shaft; The hexagonal wrench is rotated forward to drive the bidirectional threaded fastening screw to continue to rotate deeper into the threaded hole of the main shaft, and the impeller moves axially toward the main shaft relative to the bidirectional threaded fastening screw until the left end of the impeller is tightly against the main shaft; Continue to rotate the hexagonal wrench in the forward direction until the tightening torque reaches the required value.

[0007] Wherein, in the step of rotating the bidirectional threaded fastening screw in the forward direction and screwing it onto the main shaft: The remaining depth of the threaded hole in the spindle is set to L3.

[0008] Among them, in the step of sleeve the impeller on one end of the bidirectional threaded fastening screw, fixing the bidirectional threaded fastening screw by a hexagonal wrench, and rotating the impeller in the opposite direction until the triangular prism profile contacts the profile of the main shaft: The remaining depth of the threaded hole in the impeller is set to L2.

[0009] Among them, in the step of sleeve the impeller on one end of the bidirectional threaded fastening screw, fixing the bidirectional threaded fastening screw by a hexagonal wrench, and rotating the impeller in the opposite direction until the triangular prism profile contacts the profile of the main shaft: The distance between the left end of the impeller and the main shaft is set to L1.

[0010] Among them, the values ​​of L1, L2, and L3 are detected; among them, L1<2*L2, L3>L2.

[0011] The present invention provides an impeller-spindle connection structure and installation method, wherein the bidirectional threaded fastening screw is rotated forward and screwed onto the spindle; the impeller is sleeved on one end of the bidirectional threaded fastening screw, the bidirectional threaded fastening screw is fixed by a hexagonal wrench, and the impeller is rotated in the reverse direction until the impeller profile begins to contact the profile of the spindle; the hexagonal wrench is rotated forward to drive the bidirectional threaded fastening screw to continue to rotate deeper into the threaded hole of the spindle, and since the triangular prism profile restricts the impeller from rotating, the impeller moves relative to the bidirectional threaded fastening screw. Move in the direction of the main shaft until the left end of the impeller is tight against the main shaft; continue to rotate the hexagonal wrench in the forward direction until the tightening torque reaches the required value; wherein the two-way threaded fastening screw has the hexagonal hole on the side end face close to the impeller, which is convenient for installation using the hexagonal wrench, and the through hole is arranged at the small end of the impeller, and the diameter of the through hole is such that the hexagonal wrench can pass through, which can be much smaller than the diameter of the two-way threaded fastening screw. This structure ensures that the diameter of the two-way threaded fastening screw is large, and at the same time, the diameter of the small end of the impeller is as small as possible, thereby improving the connection reliability and aerodynamic efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0013] Figure 1 It is a structural schematic diagram of the impeller-spindle connection structure of the present invention.

[0014] Figure 2 It is a schematic diagram of the assembly process of the impeller and the main shaft of the present invention.

[0015] Figure 3 The present invention Figure 1 AA line structural section view.

[0016] Figure 4 It is a flow chart of the steps of the impeller main shaft installation method of the present invention.

[0017] 1-main shaft, 2-two-way thread fastening screw, 3-impeller, 4-hexagonal wrench, 5-impeller big end, 6-forward thread, 7-reverse thread, 8-triangular prism profile, 9-hexagonal hole, 10-impeller small end, 11-through hole. DETAILED DESCRIPTION

[0018] See also Figure 1~Figure 4 , Figure 1 It is a structural diagram of the impeller-spindle connection structure. Figure 2 This is a schematic diagram of the impeller and main shaft assembly process. Figure 3 yes Figure 1 AA line structural section view, Figure 4 It is a step flow chart of the impeller spindle installation method.

[0019] The present invention provides an impeller-spindle connection structure, comprising a spindle 1, a bidirectional threaded fastening screw 2 and an impeller 3, wherein the impeller 3 has a triangular prism profile 8, an impeller big end 5 and an impeller small end 10, the impeller 3 is sleeved on the outer side wall of the spindle 1, and the triangular prism profile 8 and the impeller big end 5 are respectively in contact with the spindle 1, the bidirectional threaded fastening screw 2 has a forward thread 6 and a reverse thread 7, both ends of the bidirectional threaded fastening screw 2 are respectively inserted into the spindle 1 and the impeller 3, and the forward thread 6 cooperates with the spindle 1, and the reverse thread 7 cooperates with the impeller 3, the bidirectional threaded fastening screw 2 has a hexagonal hole 9 at one end close to the impeller 3, and a through hole 11 is provided at the impeller small end 10, and the axial center line of the hexagonal hole 9 is consistent with that of the through hole 11.

[0020] In this embodiment, the bidirectional threaded fastening screw 2 has the hexagonal hole 9 on the side end surface close to the impeller 3, which is convenient for installation using the hexagonal wrench 4. The through hole 11 is provided at the small end 10 of the impeller. The diameter of the through hole 11 is such that the hexagonal wrench 4 can pass through, and can be much smaller than the diameter of the bidirectional threaded fastening screw 2. This structure ensures that the diameter of the bidirectional threaded fastening screw 2 is relatively large, and at the same time, the diameter of the impeller small end 10 is as small as possible, thereby improving the connection reliability and aerodynamic efficiency.

[0021] The present invention also provides an impeller main shaft installation method, comprising the following steps: S100: Rotate the bidirectional threaded fastening screw 2 in the forward direction and screw it onto the spindle 1, and set the remaining depth of the threaded hole in the spindle 1 to L3; S200: The impeller 3 is mounted on one end of the bidirectional threaded fastening screw 2, the bidirectional threaded fastening screw 2 is fixed by a hexagonal wrench 4, and the impeller 3 is rotated in the opposite direction until the triangular prism profile 8 contacts the profile of the main shaft 1, and the remaining depth of the threaded hole in the impeller 3 is set to L2, and the distance between the left end of the impeller 3 and the main shaft 1 is L1; S300: The hexagon socket wrench 4 is rotated forward to drive the bidirectional threaded fastening screw 2 to continue to rotate deeper into the threaded hole of the main shaft 1, and the impeller 3 moves axially toward the main shaft 1 relative to the bidirectional threaded fastening screw 2 until the left end of the impeller 3 is tightly pressed against the main shaft 1; S400: Continue to rotate the hexagonal wrench 4 in the forward direction until the tightening torque reaches the required value; S500: Detect the values ​​of L1, L2, and L3; wherein L1 < 2*L2; L3 > L2.

[0022] In this embodiment, the bidirectional threaded fastening screw 2 is first rotated in the forward direction and screwed onto the spindle 1, and the remaining depth of the threaded hole in the spindle 1 is set to L3. Then S200: the impeller 3 is mounted on one end of the bidirectional threaded fastening screw 2, the bidirectional threaded fastening screw 2 is fixed by the hexagonal wrench 4, the impeller 3 is rotated in the reverse direction, the impeller 3 moves toward the spindle 1, and the remaining depth of the threaded hole in the impeller 3 is set to L2. At this time, the profile of the impeller 3 contacts the profile of the spindle 1, and the distance between the left end of the impeller 3 and the spindle 1 is L1. Then, the hexagon socket wrench 4 is rotated forward to drive the bidirectional threaded fastening screw 2 to continue to penetrate into the threaded hole of the main shaft 1. Due to the limitation of the profile, the impeller 3 cannot rotate and can only move axially. Since the thread at the end of the impeller 3 is a reverse thread 7, and the triangular prism profile 8 limits the impeller 3 from rotating, the impeller 3 moves axially toward the main shaft 1 relative to the bidirectional threaded fastening screw 2. Therefore, the moving distance of the impeller 3 is equal to twice the moving distance of the bidirectional threaded fastening screw 2, until the left end of the impeller 3 is pressed against the main shaft 1. Then continue to rotate the hexagon socket wrench 4 forward until the tightening torque reaches the required value. At the same time, detect the values ​​of L1, L2, and L3; among which L1 < 2*L2; L3 > L2, so as to achieve the purpose of pressing the impeller 3 on the main shaft 1 with the designed tension; this structure ensures that the diameter of the bidirectional threaded fastening screw 2 is large, and the diameter of the impeller small end 10 is as small as possible, so as to improve the connection reliability and aerodynamic efficiency.

[0023] What is disclosed above is only a preferred embodiment of the present invention, and it certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. An impeller-spindle connection structure, characterized in that: It includes a main shaft, a two-way threaded fastening screw and an impeller, the impeller has a triangular prism profile, an impeller big end and an impeller small end, the impeller is sleeved on the outer side wall of the main shaft, and the triangular prism profile and the impeller big end are respectively in contact with the main shaft, the two-way threaded fastening screw has a forward thread and a reverse thread, the two ends of the two-way threaded fastening screw are respectively inserted into the main shaft and the impeller, the forward thread cooperates with the main shaft, and the reverse thread cooperates with the impeller, the two-way threaded fastening screw has a hexagonal hole at one end close to the impeller, and a through hole is provided at the impeller small end, and the hexagonal hole is consistent with the axial center line of the through hole.

2. An impeller main shaft installation method, applied to the impeller main shaft connection structure according to claim 1, characterized in that: The steps include: Rotate the bidirectional threaded fastening screw in a positive direction and screw it onto the main shaft; Sleeve the impeller onto one end of the bidirectional threaded fastening screw, fix the bidirectional threaded fastening screw with a hexagonal wrench, and rotate the impeller in the opposite direction until the triangular prism profile contacts the profile of the main shaft; The hexagonal wrench is rotated forward to drive the bidirectional threaded fastening screw to continue to rotate deeper into the threaded hole of the main shaft, and the impeller moves axially toward the main shaft relative to the bidirectional threaded fastening screw until the left end of the impeller is tightly against the main shaft; Continue to rotate the hexagonal wrench in the forward direction until the tightening torque reaches the required value.

3. The impeller main shaft installation method according to claim 2, characterized in that: In the step of rotating the bidirectional thread fastening screw in the forward direction and screwing it onto the spindle: The remaining depth of the threaded hole in the spindle is set to L3.

4. The impeller main shaft installation method according to claim 3, characterized in that: In the step of fitting the impeller onto one end of the bidirectional threaded fastening screw, fixing the bidirectional threaded fastening screw by a hexagonal wrench, and rotating the impeller in the opposite direction until the triangular prism profile contacts the profile of the main shaft: The remaining depth of the threaded hole in the impeller is set to L2.

5. The impeller main shaft installation method according to claim 4, characterized in that: In the step of fitting the impeller onto one end of the bidirectional threaded fastening screw, fixing the bidirectional threaded fastening screw by a hexagonal wrench, and rotating the impeller in the opposite direction until the triangular prism profile contacts the profile of the main shaft: The distance between the left end of the impeller and the main shaft is set to L1.

6. The impeller main shaft installation method according to claim 5, characterized in that: Detect L1, L2, and L3 values; where L1 < 2*L2, L3 > L2.

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