Replaceable test fan structure for motor air cooling test

Abstract

The present invention discloses a replaceable test fan structure for a motor air-cooling test, comprising a test motor body, a columnar fan test support being detachably coaxially mounted on the rear end of a rotor shaft of the motor body, a synchronous sleeve at the axis of a fan to be tested being coaxially and synchronously mounted outside the fan test support; a ring sleeve is integrally arranged at one end of the fan test support close to the rotor shaft, a plurality of hollow stud through holes are distributed in a circular array on the ring sleeve; the cooling intensity of fans with different blade models on the test motor body at the same rotation speed and the energy consumption rate of fans with different blade models at the same rotation speed can be verified.

Description

Technical Field

[0001] The invention belongs to the field of motor testing. Background Art

[0002] When designing the IE5 motor, the selection of the fan is crucial. It is necessary to consider both the minimum mechanical loss to make the motor more efficient and the air volume and cooling efficiency. As a result, it is necessary to select a suitable fan from a variety of fan models, so repeated replacement tests and experiments are required. For this reason, it is necessary to design a detachable test fan installation structure, so that the frequency of disassembly can be reduced when doing the trial production of the new IE5 product. In order to meet the lightweight requirements, various models of fans use non-metallic plastics as the main material. Therefore, during the test, the wind load on each blade on the fan cannot be too large. The blades are at risk of being damaged under high wind loads, and excessive wind loads also pose certain risks to the test. Summary of the invention

[0003] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a replaceable test fan structure for motor air-cooling test, which can verify the cooling intensity of fans with different blade models on the test motor body at the same speed, as well as the energy consumption rate of fans with different blade models at the same speed.

[0004] Technical solution: To achieve the above-mentioned purpose, the replaceable test fan structure of the motor air-cooling test of the present invention comprises a test motor body, a columnar fan test support is detachably installed coaxially at the tail end of the rotor shaft of the motor body, and a synchronous sleeve at the axis of the tested fan is synchronously installed coaxially outside the fan test support;

[0005] A ring sleeve is integrally provided at one end of the fan test support close to the rotor shaft, and a plurality of hollow stud through holes are distributed in a circular array on the ring sleeve.

[0006] Furthermore, the outer ring at the rear end of the rotor shaft is rotatably sleeved with a rotating sleeve through a bearing, and a plurality of threaded locking holes are arranged in a circular array on the rotating sleeve, each threaded locking hole corresponds to each stud through hole; each bolt passes through each stud through hole and is locked on the corresponding threaded locking hole.

[0007] Furthermore, a hexagonal hole a is provided at the axis center of the tail end of the rotor shaft; a columnar central channel is provided at the axis center of the fan test support, a static friction fixing column is provided coaxially in the central channel, and the outer peripheral surface of the static friction fixing column is rotatably matched with the inner wall of the columnar central channel through a pair of b bearings;

[0008] The static friction fixed column is coaxially fixed with a central column at one end close to the rotor shaft, and the central column also includes a hexagonal column coaxially outside the central column, which is movably inserted into the matching a hexagonal hole along the axial direction, and the cylindrical inner wall of the hexagonal column and the outer wall of the central column are rotatably matched through a pair of c bearings.

[0009] Furthermore, the static friction fixing column and the hexagonal column are connected by a torsion transmission method of a coaxial torsion spring.

[0010] Furthermore, a structural disk is provided on one side of the static friction fixed column away from the central column, and the outer ring of the structural disk is integrally fixed to the inner wall of the fan test support;

[0011] A conical concave friction surface is coaxially arranged at one end of the static friction fixing column close to the structural disk; a hexagonal hole b with a regular hexagonal axial angle of view passes through the axis of the structural disk, a hexagonal guide rod with a regular hexagonal cross-section movably passes through the hexagonal hole b, a push plate is coaxially fixed to the end of the hexagonal guide rod close to the conical concave friction surface, and a conical annular friction plate adapted to the conical concave friction surface is coaxially arranged on the outer contour of the push plate; a thrust spring in a compressed state is coaxially arranged between the conical annular friction plate and the structural plate, and the conical annular friction plate is coaxially pressed against and presses against the conical concave friction surface under the elastic thrust of the thrust spring.

[0012] Furthermore, under normal conditions, the thrust spring applies thrust to the conical annular friction disc, so that the static friction fixing column cannot rotate along the axis due to the static friction between the conical annular friction disc and the conical concave friction surface pressing against each other.

[0013] Further, it also includes a first rotation angle sensor and a second rotation angle sensor;

[0014] The first rotation angle sensor can identify the relative rotation angle between the hexagonal column and the central column;

[0015] The second rotation angle sensor can identify the relative rotation angle between the static friction fixing column and the fan test support.

[0016] Furthermore, a push rod passage is provided inside the integrated structure formed by the static friction fixed column and the central column along the axial direction, a hole plate is provided coaxially on the inner wall of one end of the hexagonal column away from the static friction fixed column, a threaded transmission hole is provided along the axis at the center of the hole plate, and a flange is provided on the inner wall of the push rod passage, and the inner circle of the flange is a c hexagonal guide hole that is through along the axis;

[0017] It also includes a hexagonal push rod coaxially arranged in the push rod channel, the hexagonal push rod movably passes through the matching C hexagonal guide hole, the hexagonal push rod is fixedly connected to a push head with a spherical top surface at the end close to the push plate, a travel gap is formed between the push head and the push plate, and the end of the hexagonal push rod away from the push head is coaxially fixedly connected to a threaded transmission rod, and the threaded transmission rod is threadedly matched with the threaded transmission hole.

[0018] Furthermore, when excessive torsion occurs during the process of torque transmission by the torsion spring, the relative rotation angle between the threaded transmission rod and the hole plate exceeds a preset value, and under the threaded transmission of the threaded transmission rod and the threaded transmission hole, the hexagonal push rod drives the push head to gradually approach the push plate under the guidance of the hexagonal guide hole C, and the push head moves enough to contact the push plate and push the push plate. The force of the push head pushing the push plate overcomes a part of the thrust of the thrust spring, so that the pressure between the conical annular friction plate and the conical concave friction surface is reduced, thereby further reducing the maximum static friction between the conical annular friction plate and the conical concave friction surface.

[0019] Beneficial effect: The present invention can verify the cooling intensity of fans with different blade models on the test motor body at the same rotation speed, and the energy consumption rate of fans with different blade models at the same rotation speed.

[0020] When the wind load of the fan is too large, excessive torsion will occur in the process of transmitting torque by the torsion spring, so that the relative rotation angle between the threaded transmission rod and the hole plate exceeds the preset value, so that under the threaded transmission of the threaded transmission rod and the threaded transmission hole, the hexagonal push rod drives the push head to gradually approach the push plate under the guidance of the c hexagonal guide hole, and the push head is moved enough to contact the push plate and push the push plate. The force of the push head pushing the push plate overcomes part of the thrust of the thrust spring, so that the pressure between the conical annular friction plate and the conical concave friction surface is reduced, and the maximum static friction between the conical annular friction plate and the conical concave friction surface is further reduced, so that the conical annular friction plate and the conical concave friction surface slip due to the reduction of the maximum static friction, and then relative rotation occurs, so that the speed of the fan begins to be lower than the speed of the motor, automatically alleviating the problem of excessive wind load. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Attached Figure 1 It is a schematic diagram for replacing various types of fans;

[0022] Attached Figure 2 This is a schematic diagram of the machine, hiding the test fan to be tested;

[0023] Attached Figure 3 It is a three-dimensional cross-sectional view of the rotor shaft tail end and the fan test support in the matching state;

[0024] Attached Figure 4 This is a cross-sectional diagram of the rotor shaft tail end and the fan test support in the matching state.

[0025] Attached Figure 5 This is a disassembly diagram of the fan test support. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the accompanying drawings.

[0027] As attached Figures 1 to 5 The replaceable test fan structure of the motor air-cooling test shown includes a test motor body 1, a columnar fan test support 7 is detachably installed coaxially at the rear end of the rotor shaft 2 of the motor body 1, and a synchronous sleeve 15 at the axis of the tested fan 14 is coaxially and synchronously installed outside the fan test support 7; an annular sleeve 8 is integrally provided at one end of the fan test support 7 close to the rotor shaft 2, and a plurality of hollow stud through holes 100 are distributed in a circular array on the annular sleeve 8; the outer ring at the rear end of the rotor shaft 2 is rotatably sleeved with a rotating sleeve 13 through a bearing a 9, and a plurality of threaded locking holes 10 are arranged in a circular array on the rotating sleeve 9, and each threaded locking hole 10 corresponds to each stud through hole 100; each bolt 3 passes through each stud through hole 100 and is locked on the corresponding threaded locking hole 10.

[0028] like Figure 2 A keyway 4 is provided on the cylindrical surface of the fan test support 7, and a circle of retaining ring grooves 5 are provided on the outer ring of the free end of the fan test support 7; a synchronous sleeve 15 of the axis of the tested fan 14 is coaxially sleeved outside the fan test support 7, and is synchronized with the fan test support 7 through the keyway; after the retaining ring is inserted into the retaining ring groove 5, the tested fan 14 is completely positioned.

[0029] like Figure 3 , 4, 5; a hexagonal hole a 11 with an axial perspective of a regular hexagon is provided at the axis center of the tail end of the rotor shaft 2; a columnar central channel 6 is provided at the axis center of the fan test support 7, and a static friction fixing column 20 is coaxially provided in the central channel 6, and the outer peripheral surface of the static friction fixing column 20 is rotatably matched with the inner wall of the columnar central channel 6 through a pair of b bearings 9; a central column 33 is integrally fixed coaxially at one end of the static friction fixing column 20 close to the rotor shaft 2, and the central column 33; also includes a hexagonal column 32 with an outer contour of a regular hexagon coaxially outside the central column 33, the hexagonal column 32 is movably inserted into the matching hexagonal hole a 11 along the axial direction, and a cylindrical inner wall of the hexagonal column 32 and an outer wall of the central column 33 are connected by a The C bearing 31 is rotatably matched; the static friction fixed column 20 and the hexagonal column 32 are connected for torque transmission through a coaxial torsion spring 34. When the static friction fixed column 20 and the hexagonal column 32 rotate relative to each other along the axis, the torsion spring 34 undergoes corresponding elastic torsional deformation, thereby transmitting torque; the greater the degree of torsion of the torsion spring 34, the greater the transmitted torque. The first rotation angle sensor 221 records the relative rotation angle of the static friction fixed column 20 and the hexagonal column 32. The relative rotation angle of the static friction fixed column 20 and the hexagonal column 32 recorded by the first rotation angle sensor 221 is positively correlated with the magnitude of the torque transmitted by the torsion spring 34, and there is a one-to-one correspondence.

[0030] A structural disk 39 is arranged on the side of the static friction fixing column 20 away from the central column 33, and the outer ring of the structural disk 39 is integrally fixed to the inner wall of the fan test support 7; a conical concave friction surface 17 is coaxially arranged at one end of the static friction fixing column 20 close to the structural disk 39; a hexagonal hole 16 with an axial perspective of a regular hexagon passes through the axis of the structural disk 16, and a hexagonal guide rod 40 with a regular hexagonal cross-section that is movable and fits through the hexagonal hole 16, and a push plate 38 is integrally fixed to the end of the hexagonal guide rod 40 close to the conical concave friction surface 17 coaxially, and the outer contour of the push plate 38 is integrally fixed. A conical annular friction disc 19 adapted to the conical concave friction surface 17 is coaxially arranged; a thrust spring 18 in a compressed state is coaxially arranged between the conical annular friction disc 19 and the structural disc 39, and the conical annular friction disc 19 is coaxially pressed against and presses against the conical concave friction surface 17 under the elastic thrust of the thrust spring 18; under normal conditions, the thrust spring 18 applies a sufficiently large thrust to the conical annular friction disc 19, thereby preventing the static friction fixing column 20 from rotating along the axis due to the static friction force between the conical annular friction disc 19 and the conical concave friction surface 17 pressing against each other.

[0031] It also includes a first rotation angle sensor 221, which can identify the relative rotation angle between the hexagonal column 32 and the central column 33; the first rotation angle sensor 221 includes a Hall element 25 and a magnetic encoder magnet 27 that cooperate with each other, the Hall element 25 is fixedly installed on the inner wall of the hexagonal column 32, and the magnetic encoder magnet 27 is coaxially fixed on the outer wall of the central column 33; the principle is that when the magnetic encoder magnet 27 rotates a certain angle relative to the Hall element 25, the magnetic field change it generates is sensed by the Hall element 25, and then converted into an electrical signal output, so as to deduce the relative rotation angle between the hexagonal column 32 and the central column 33. This cooperation mode has the characteristics of high sensitivity, high resolution and fast response.

[0032] It also includes a second rotation angle sensor 220, which can identify the relative rotation angle between the static friction fixed column 20 and the fan test support 7; the second rotation angle sensor 220 includes a b Hall element 21 and a b magnetic encoder magnet 22 that cooperate with each other, the b Hall element 21 is fixedly installed on the inner wall of the fan test support 7, and the b magnetic encoder magnet 22 is coaxially fixed on the outer wall of the static friction fixed column 20.

[0033] The internal part of the integrated structure formed by the static friction fixed column 20 and the central column 33 is provided with a through push rod channel 36 along the axial direction, and the inner wall of the end of the hexagonal column 32 away from the static friction fixed column 20 is provided with a hole plate 28 coaxially, and the center of the hole plate 28 is provided with a threaded transmission hole 30 that passes through along the axis. The inner wall of the push rod channel 36 is provided with a flange 24, and the inner circle of the flange 24 is a c hexagonal guide hole 23 that passes through along the axis and has a regular hexagonal outline from an axial perspective; it also includes a push rod A hexagonal push rod 26 with a regular hexagonal shape from an axial perspective coaxially arranged in the channel 36 can move through the matching c hexagonal guide hole 23. A push head 37 with a spherical top surface at the end is fixedly connected to the hexagonal push rod 26 near the push plate 38. A travel gap 101 is formed between the push head 37 and the push plate 38. A threaded transmission rod 29 is coaxially fixedly connected to the end of the hexagonal push rod 26 away from the push head 37. The threaded transmission rod 29 is threadedly matched with the threaded transmission hole 30.

[0034] Working Principle: Preparation:

[0035] In the initial state, the columnar fan test support 7 is coaxially installed on the tail end of the rotor shaft 2 of the motor body 1, and the bolts 3 are locked, and the hexagonal column 32 is in a state of being movably inserted into the matching hexagonal hole a 11 along the axial direction; then, one type of fan 14 to be tested is selected and coaxially fixedly installed outside the fan test support 7. When the motor body 1 is not started, the fan 14 does not rotate and there is no wind load, and the torsion spring 34 does not transmit torque; at this point, the preparation work for the test is completed.

[0036] test:

[0037] Temperature sensors are arranged at corresponding positions in the motor heat dissipation housing of the test motor body 1 to verify the cooling intensity of the test motor body 1 by fans 14 with different blade models at the same rotation speed, and the energy consumption rate of fans 14 with different blade models at the same rotation speed.

[0038] Theoretically, at the same rotation speed, the higher the cooling intensity of the fan 14 on the motor, the better, and the lower the energy consumption rate of the fan 14, the better; the conclusion of this experiment provides an experimental reference for the selection of the fan.

[0039] Test procedure for any fan 14:

[0040] Start the test motor body 1, and accelerate the speed of the test motor body 1 to reach the preset speed, thereby driving the fan 14 to rotate synchronously, and continue to run stably for a predetermined time. During the operation of the test motor body 1, heat is released due to the thermal effect, and the wind flow generated during the high-speed rotation of the tested fan 14 will blow through the surface of the heat dissipation shell of the motor body 1 at high speed, thereby achieving the purpose of active heat dissipation. In a stable state, the lower the temperature of the temperature sensor in the motor heat dissipation shell of the test motor body 1, the higher the cooling intensity of the fan 14 to the motor; therefore, the heat dissipation intensity of different fans 14 to the test motor body 1 at the same speed can be compared through the temperature of the temperature sensor in the motor heat dissipation shell;

[0041] At the same time, a certain wind load will be generated during the high-speed rotation of the fan 14. The torque generated by the wind load on the fan 14 is successively transmitted through the fan test support 7, the structural disk 39, the hexagonal guide rod 40, the conical annular friction disk 19, the static friction fixing column 20, the torsion spring 34 and the hexagonal column 32 and finally transmitted to the rotor shaft 2. Since the thrust spring 18 applies a sufficiently large thrust to the conical annular friction disk 19, the static friction fixing column 20 cannot rotate along the axis under the action of the static friction force between the conical annular friction disk 19 and the conical concave friction surface 17 that press against each other. In this state, the second rotation angle sensor 220 does not recognize the relative rotation. The torsion spring 34 will twist around the axis during the process of transmitting the torque. The static friction fixing column 20 and the hexagonal column 32 are caused to rotate relative to each other along the axis. The greater the twisting degree of the torsion spring 34 is, the greater the torque transmitted is. The first rotation angle sensor 221 records the relative rotation angle of the static friction fixing column 20 and the hexagonal column 32. The relative rotation angle of the static friction fixing column 20 and the hexagonal column 32 recorded by the first rotation angle sensor 221 is positively correlated with the torque transmitted by the torsion spring 34, and there is a one-to-one correspondence. Then, the relative rotation angle of the static friction fixing column 20 and the hexagonal column 32 recorded by the first rotation angle sensor 221 is used to infer the wind load torque of the fan 14 at the rotation speed. The energy consumption power of the fan 14 can be roughly estimated by multiplying the wind load torque by the rotation speed.

[0042] At the same time, from the perspective of transmission relationship, the relative rotation between the static friction fixed column 20 and the hexagonal column 32 will directly cause the threaded transmission rod 29 and the hole plate 28 to rotate relative to each other. Under the threaded transmission of the threaded transmission rod 29 and the threaded transmission hole 30, the hexagonal push rod 26 drives the push head 37 to gradually approach the push plate 38 under the guidance of the c hexagonal guide hole 23. Since there is a certain distance in the stroke gap 101, under normal circumstances, the push head 37 is not enough to move to contact the push plate 38. Therefore, under normal circumstances, the axial displacement of the hexagonal push rod 26 does not bear any load.

[0043] In order to meet the requirements of light weight, various models of fans 14 are made of non-metallic plastics as the main material. Therefore, the wind load on the blades of the fan 14 cannot be too large. The blades are at risk of being damaged under high wind loads. Excessive wind loads also pose certain risks to the test, so wind load protection is required.

[0044] When the wind load of the fan 14 is too large, excessive torsion will occur in the process of transmitting torque by the torsion spring 34, so that the relative rotation angle between the threaded transmission rod 29 and the hole plate 28 exceeds the preset value, so that under the threaded transmission of the threaded transmission rod 29 and the threaded transmission hole 30, the hexagonal push rod 26 drives the push head 37 to gradually approach the push plate 38 under the guidance of the c hexagonal guide hole 23, and the push head 37 is moved enough to contact the push plate 38 and push the push plate 38. The force of the push head 37 pushing the push plate 38 overcomes a part of the thrust of the thrust spring 18, so that the pressure between the conical annular friction plate 19 and the conical concave friction surface 17 is reduced, and the maximum static friction between the conical annular friction plate 19 and the conical concave friction surface 17 is further reduced, so that the conical annular friction plate 19 and the conical concave friction surface 17 slip due to the reduction of the maximum static friction, and then relative rotation occurs, so that the speed of the fan 14 begins to be lower than the motor speed, and the problem of excessive wind load is automatically alleviated;

[0045] At the same time, once the conical annular friction disk 19 and the conical concave friction surface 17 slip and rotate relative to each other due to the reduction of the maximum static friction force, relative rotation will inevitably occur between the static friction fixing column 20 and the fan test support 7, so that the second rotation angle sensor 220 senses the relative rotation angle between the static friction fixing column 20 and the fan test support 7. When the second rotation angle sensor 220 senses the relative rotation angle between the static friction fixing column 20 and the fan test support 7, the system automatically cuts off the power or reduces the speed of the test motor body 1 to avoid excessive slippage and wear between the conical annular friction disk 19 and the conical concave friction surface 17.

[0046] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. The replaceable test fan structure for the motor air cooling test is characterized by: The invention comprises a test motor body (1), wherein a columnar fan test support (7) is detachably and coaxially mounted at the rear end of a rotor shaft (2) of the motor body (1), and a synchronous sleeve (15) at the axis of a fan (14) to be tested is coaxially and synchronously mounted outside the fan test support (7); The fan test support (7) is integrally provided with a ring sleeve (8) at one end close to the rotor shaft (2), and a plurality of hollow stud through holes (100) are distributed in a circular array on the ring sleeve (8); A hexagonal hole (11) is provided at the axis center of the tail end of the rotor shaft (2); a columnar central channel (6) is provided at the axis center of the fan test support (7); a static friction fixing column (20) is coaxially provided in the central channel (6); the outer peripheral surface of the static friction fixing column (20) is rotatably matched with the inner wall of the columnar central channel (6) via a pair of b bearings (9); The static friction fixed column (20) has a central column (33) integrally fixed coaxially at one end close to the rotor shaft (2), and the central column (33) also includes a hexagonal column (32) coaxially outside the central column (33), the hexagonal column (32) being movably inserted into a matching hexagonal hole (11) along the axial direction, and the cylindrical inner wall of the hexagonal column (32) and the outer wall of the central column (33) are rotatably matched via a pair of c bearings (31); The static friction fixing column (20) and the hexagonal column (32) are connected to torsion force by a coaxial torsion spring (34); A structural disk (39) is provided on a side of the static friction fixed column (20) away from the central column (33), and an outer ring of the structural disk (39) is integrally fixed to an inner wall of a fan test support (7); A conical concave friction surface (17) is coaxially arranged at one end of the static friction fixing column (20) close to the structural disk (39); a hexagonal hole (16) having an axial view of a regular hexagon passes through the axis of the structural disk (16); a hexagonal guide rod (40) having a regular hexagonal cross section movably passes through the hexagonal hole (16); a push plate (38) is coaxially fixed to the end of the hexagonal guide rod (40) close to the conical concave friction surface (17); a conical annular friction plate (19) adapted to the conical concave friction surface (17) is coaxially arranged on the outer contour of the push plate (38); a thrust spring (18) in a compressed state is coaxially arranged between the conical annular friction plate (19) and the structural disk (39); the conical annular friction plate (19) is coaxially pressed against and presses against the conical concave friction surface (17) under the elastic thrust of the thrust spring (18); The integral structure formed by the static friction fixed column (20) and the central column (33) is provided with a push rod channel (36) extending along the axial direction; the inner wall of the end of the hexagonal column (32) away from the static friction fixed column (20) is provided with a hole plate (28) coaxially and integrally; the hole plate (28) is provided with a threaded transmission hole (30) extending along the axial direction; the inner wall of the push rod channel (36) is provided with a flange (24); the inner ring of the flange (24) is a c hexagonal guide hole (23) extending along the axial direction; The invention also comprises a hexagonal push rod (26) coaxially arranged in the push rod channel (36), the hexagonal push rod (26) movably passing through the matching c hexagonal guide hole (23), the hexagonal push rod (26) being fixedly connected to a push head (37) having a spherical top surface at the end thereof on one side close to the push plate (38), a travel gap (101) being formed between the push head (37) and the push plate (38), and a threaded transmission rod (29) being coaxially fixedly connected to one end of the hexagonal push rod (26) away from the push head (37), the threaded transmission rod (29) being threadedly matched with the threaded transmission hole (30).

2. The replaceable test fan structure for motor air cooling test according to claim 1 is characterized in that: The outer ring of the rear end of the rotor shaft (2) is rotatably sleeved with a rotating sleeve (13) via a bearing (9); the rotating sleeve (9) is provided with a plurality of threaded locking holes (10) in a circumferential array, each threaded locking hole (10) corresponding to each stud through hole (100); each bolt (3) passes through each stud through hole (100) and is locked on the corresponding threaded locking hole (10).

3. The replaceable test fan structure for motor air cooling test according to claim 1 is characterized in that: Under normal conditions, the thrust force applied by the thrust spring (18) to the conical annular friction disc (19) prevents the static friction fixing column (20) from rotating along the axis due to the static friction force between the conical annular friction disc (19) and the conical concave friction surface (17) pressing against each other.

4. The replaceable test fan structure for motor air cooling test according to claim 3 is characterized in that: Also included is a first rotation angle sensor (221) and a second rotation angle sensor (220); The first rotation angle sensor (221) can identify the relative rotation angle between the hexagonal column (32) and the central column (33); The second rotation angle sensor (220) is capable of identifying the relative rotation angle between the static friction fixing column (20) and the fan test support (7).

5. The replaceable test fan structure for motor air cooling test according to claim 1, characterized in that: When excessive torsion occurs during the torque transmission process of the torsion spring (34), the relative rotation angle between the threaded transmission rod (29) and the hole plate (28) exceeds a preset value. Under the threaded transmission of the threaded transmission rod (29) and the threaded transmission hole (30), the hexagonal push rod (26) drives the push head (37) to gradually approach the push plate (38) under the guidance of the hexagonal guide hole (23), and the push head (37) moves sufficiently to contact the push plate (38) and push the push plate (38). The force of the push head (37) pushing the push plate (38) overcomes a part of the thrust of the thrust spring (18), so that the pressure between the conical annular friction plate (19) and the conical concave friction surface (17) is reduced, thereby further reducing the maximum static friction between the conical annular friction plate (19) and the conical concave friction surface (17).

Images