CN112229554B

CN112229554B - Dynamometer

Info

Publication number: CN112229554B
Application number: CN202011016828.8A
Authority: CN
Inventors: 孙红辉
Original assignee: Taizhou Guangzhong Electrical Equipment Co ltd
Current assignee: Taizhou Guangzhong Electrical Equipment Co ltd
Priority date: 2020-09-24
Filing date: 2020-09-24
Publication date: 2021-11-16
Anticipated expiration: 2040-09-24
Also published as: CN112229554A

Abstract

The utility model relates to a dynamometer machine relates to the field of power measurement equipment, the loach carrying platform comprises a supporting fram, the support frame on be connected with the load machine, the load machine include end cover, rotor and stator, the end cover includes front end housing and rear end cap, the front end housing is connected in the one end of stator, the rear end cap is connected in the other end of stator, the support frame on still be equipped with sensor and support piece, the at least one end of load machine be connected with the support frame through support piece, the sensor be used for detecting the stator rotation volume, support piece include go-between, solid fixed ring and connecting piece, go-between and solid fixed ring set up with one heart, connecting piece one end be connected with the go-between, the other end is connected with solid fixed ring, solid fixed ring and support frame fixed connection, the go-between with the end cover be connected. The application has the characteristics of compact structure, lower cost and higher precision.

Description

Dynamometer

Technical Field

The application relates to the field of power measuring equipment, in particular to a dynamometer.

Background

The dynamometer can be used for testing the torque, the rotating speed and the like of the motor, can also be used for detecting the delivery of motor products on a production line, and can be used for testing all performance curves of the motor from no load to locked rotor. The method comprises the following steps of detecting conditions such as input voltage, current, power and the like while testing the performance of a motor at no-load and load points; therefore, production research personnel can better master the parameters and the use condition of the motor, and improvement measures can be conveniently made. The conventional dynamometer (composed of a loading machine, a rotary torque and rotation speed sensor and a coupling) senses the torque of a motor through a sensor, and the accuracy of the conventional dynamometer depends on the measurement accuracy of the sensor and the installation accuracy of the coupling arranged at the front and the rear of the sensor.

The novel dynamometer which is applied by the inventor under the application number of 201910975855.9 comprises a fixing mechanism, a stator shell, a rotor, an end cover, a bearing, a rotating speed measuring device and a torque measuring device; the fixing mechanism comprises a bottom plate, a supporting seat and a mounting seat; the end cover comprises a front end cover and a rear end cover; the fixing mechanism supports other structures, the stator shell is fixed on the fixing mechanism, the stator is arranged in the stator shell, and the rotor is connected with the supporting seat and the mounting seat through a bearing; the rotating speed measuring device is arranged on the rotor rotating shaft, is connected with the rear end cover through a connecting piece and is used for measuring the rotating speed; the torque measuring device is arranged on the mounting seat and connected with the stator to measure torque.

With respect to the related art in the above, the inventor considers that there are defects in which the rotational inertia generated at the time of measurement and the frictional resistance of the bearing during rotation have a large influence on the measurement accuracy.

Disclosure of Invention

In order to enable the measurement accuracy of the dynamometer to be higher, the application provides the dynamometer.

The dynamometer provided by the application adopts the following technical scheme:

the utility model provides a dynamometer, includes the support frame, the support frame on be connected with the load machine, the load machine include end cover, rotor and stator, the end cover includes front end housing and rear end cap, front end housing connects in the one end of stator, the rear end cap is connected in the other end of stator, the support frame on still be equipped with sensor and support piece, at least one end of load machine be connected with the support frame through support piece, the sensor be used for detecting the stator rotation volume, support piece include go-between, solid fixed ring and connecting piece, go-between and solid fixed ring set up with one heart, connecting piece one end be connected with the go-between, the other end is connected with solid fixed ring, solid fixed ring and support frame fixed connection, the go-between with the end cover be connected.

By adopting the technical scheme, when the motor shaft testing device is used, the motor shaft of the motor to be tested is connected with the motor shaft of the loading machine through the coupler, then the motor to be tested rotates and drives the motor shaft of the loading machine to rotate, and in the rotating process of the motor shaft of the loading machine, the electromagnetic torque of the loading machine is simultaneously applied to the stator and the rotor. The torque that the stator received equals with the torque that the rotor received, and the opposite direction, so the epaxial torque of motor can be measured by on the stator, and end cover and go-between are connected, and the go-between is connected through connecting piece and solid fixed ring, gu fixed ring and support frame fixed connection, therefore the go-between can take place slight rotation under the effect of end cover, through the pivoted detection of sensor to the go-between to the torque of calculating. Therefore, in the using process, the torque can be converted by detecting the data of the connecting ring through the sensor, and the rotation trend of the end cover can be directly reflected on the connecting ring due to the fact that the end cover is directly connected with the connecting ring, so that the measurement accuracy of the torque is higher.

Preferably, the sensor is an angular displacement sensor for detecting a rotation angle of the connection ring.

By adopting the technical scheme, when the stator is used, the angular displacement sensor is used for detecting the rotation quantity of the adapter ring, so that the torque of the stator is converted.

Preferably, the number of the connecting pieces is at least two, and the connecting pieces are circumferentially arrayed between the connecting ring and the fixing ring.

Through adopting above-mentioned technical scheme, when the go-between rotates, can make the connecting piece take place deformation, consequently set up two at least connecting pieces and connecting piece circumference array between go-between and solid fixed ring, can make the connection effect of solid fixed ring and go-between better, also can reduce the probability of damaging between the junction of go-between and connecting piece simultaneously.

Preferably, the connecting piece comprises a connecting body, a first reinforcing body and a second reinforcing body, one end of the first reinforcing body is connected with the connecting body, the other end of the first reinforcing body is connected with the fixing ring, one end of the second reinforcing body is connected with the connecting body, and the other end of the second reinforcing body is connected with the connecting ring.

By adopting the technical scheme, in the using process, the connecting ring and the connecting body are connected through the second reinforcing body, and the first reinforcing body are connected with the fixing ring, so that the connection strength of the fixing ring and the connecting ring can be further enhanced, and the probability that the connection part of the connecting ring and the fixing ring is easily damaged under the condition of multiple times of use is reduced.

Preferably, the fixing ring comprises a first ring body and a second ring body which are connected, the first ring body and the second ring body are arranged concentrically, the width of the second ring body is smaller than that of the first ring body, the surface, close to the loading machine, of the second ring body protrudes out of the outer surface of the first ring body, the first ring body is fixedly connected with the supporting seat, and the second ring body is fixedly connected with the first reinforcing body.

By adopting the technical scheme, when the connecting ring is used, the surface of the ring body II, which is close to the load machine, protrudes out of the outer surface of the ring body I, and the ring body II is fixedly connected with the reinforcement body I, so that the connecting ring is closer to the load machine, and the connecting ring is more convenient to connect with the load machine.

Preferably, the fixed ring further comprises a reinforcing ring, the reinforcing ring comprises a first reinforcing surface, a second reinforcing surface and a first inclined surface, the first reinforcing surface is perpendicular to the second reinforcing surface, the second reinforcing surface is connected with the second ring body, the first reinforcing surface is connected with the first ring body, one end of the first inclined surface is connected with the first reinforcing surface, the other end of the first inclined surface is connected with the second inclined surface, and the first inclined surface is gradually close to the loading machine towards the center of the circle of the reinforcing ring.

Through adopting above-mentioned technical scheme, because the width of ring body two is less than the width of ring body one, and ring body two protrusion in ring body one, consequently the area of connection of ring body one and ring body two can diminish, consequently the existence of beaded finish can strengthen the joint strength of ring body two and ring body one.

Preferably, the support frame on be equipped with the protection casing, the protection casing on be equipped with the gas pocket, the support frame include the base and set up at preceding backup pad at base both ends, back backup pad, preceding backup pad be located one side of the front end housing of load machine, back backup pad be located one side of the rear end housing of load machine, protection casing one end be connected with preceding backup pad, the other end is connected with back backup pad, the load machine be located the cavity that preceding backup pad, protection casing and back backup pad formed, protection casing and stator form gas flow channel, gas flow channel with the gas pocket be linked together.

Through adopting above-mentioned technical scheme, when using, because the existence of protection casing, can play the guard action, the load machine need not the casing, and then makes the weight of load machine reduce, and the load machine can produce the heat in the course of the work simultaneously, owing to cancelled the casing, the heat can direct conduction to gas flow channel department, and the air of gas flow channel department can be heated the inflation to discharge from the gas pocket, and then reinforcing radiating effect.

Preferably, the front support plate is provided with a first air guide flow passage, and the first air guide flow passage is communicated with the gas flow passage.

Through adopting above-mentioned technical scheme, at the during operation, the fan sends into in wind-guiding runner one with external gas to enter into gas flow channel department, consequently more help giving off the heat of gas flow channel department, the reinforcing is to the radiating effect of load machine.

Preferably, the stator is provided with heat dissipation holes, and the heat dissipation holes are communicated with the first air guide flow channel.

Through adopting above-mentioned technical scheme, the radiating effect to the stator can further be strengthened to the existence of louvre, and then the reinforcing is to the heat dissipation of load machine.

In summary, the present application includes at least one of the following beneficial technical effects:

the whole structure is more compact, the measurement precision is more accurate, and the cost is lower;

the supporting piece has simple structure, and is difficult to damage due to repeated deformation;

the loading machine is fixedly arranged on the supporting frame through the supporting piece, so that the loading machine is not easy to vibrate.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present application.

Fig. 2 is a schematic diagram of an explosive structure according to an embodiment of the present application.

Fig. 3 is a schematic cross-sectional structure diagram of an embodiment of the present application.

Fig. 4 is a schematic structural diagram of a support member according to an embodiment of the present application.

Fig. 5 is a schematic cross-sectional structural view of a support member according to an embodiment of the present application.

Description of reference numerals: 1. a support frame; 11. a front support plate; 111. a first air guide flow channel; 112. a second air guide flow channel; 12. a base; 121. a wind flow channel; 13. a rear support plate; 131. a wind hole; 14. a mounting cavity; 2. a loading machine; 2111. heat dissipation holes; 212. a front end cover; 213. a rear end cap; 221. a rotor; 222. a stator; 3. a support member; 31. a fixing ring; 311. a ring body I; 312. a second ring body; 32. a connecting ring; 33. a connecting member; 331. a linker; 332. a first reinforcement body; 333. a second reinforcing body; 34. a reinforcement ring; 341. a first inclined surface; 35. a yielding groove; 41. a connecting shaft; 42. an angular displacement sensor; 5. a protective cover; 51. a gas flow channel; 52. and (4) air holes.

Detailed Description

The present application is described in further detail below with reference to figures 1-5.

The embodiment of the application discloses a dynamometer. Referring to fig. 1 and 2, the supporting frame 1 is included, a protective cover 5 is fixedly connected to the supporting frame, an air hole 52 is formed in the protective cover 5, a load machine 2 is rotatably connected to the supporting frame 1, the supporting frame 1 includes a base 12, a front supporting plate 11 and a rear supporting plate 13 which are arranged on the base 12, the load machine 2 is located in a cavity formed by the front supporting plate 11, the rear supporting plate 13 and the protective cover 5, the air hole 52 is communicated with the cavity, the air hole is located at one end of the protective cover 5 close to the rear supporting plate 13, the front supporting plate 11 and the rear supporting plate 13 are respectively provided with a mounting cavity 14, the load machine 2 includes an end cover, a rotor 221 and a stator 222, the end cover includes a front end cover 212 and a rear end cover 213, an air flow passage 51 is formed between the stator 222 and the protective cover 5, more specifically, the air flow passage 51 is 1-2mm, the front end cover 212 is connected to one end of the stator 222, the rear end cover 213 is connected to the other end of the stator 222, the support frame 1 is further provided with two sensors and two supports 3, the two supports 3 are located at two ends of the loading machine 2, one support 3 is connected with the front support plate 11, the other support 3 is connected with the rear support plate 13, the sensors are used for detecting the rotation amount of the stator 222, each support 3 comprises a connecting ring 32, a fixing ring 31 and connecting pieces 33, the connecting rings 32 and the fixing rings 31 are concentrically arranged, one end of each connecting piece 33 is connected with the connecting ring 32, the other end of each connecting piece 33 is connected with the fixing ring 31, the number of the connecting pieces 33 is at least two, the number of the connecting pieces 33 is four in the embodiment, and the connecting pieces 33 are circumferentially arrayed between the connecting rings 32 and the fixing rings 31. The support 3 is made by an integral molding process. Referring to fig. 3, in the present embodiment, the sensor is an angular displacement sensor 42, more specifically, a hollow shaft angular displacement sensor, the angular displacement sensor 42 is used for detecting a rotation angle of the connection ring 32, the angular displacement sensor 42 is fixedly mounted on the rear support plate 13, the angular displacement sensor 42 is fixedly connected to the connection ring 32 through a connection shaft 41, that is, an outer circumferential surface of the connection shaft 41 is fixedly connected to an inner circumferential surface of the connection ring 32, and the other end of the connection shaft extends into the angular displacement sensor 42 and is connected to the angular displacement sensor.

Referring to fig. 3 and 4, the fixing ring 31 is fixedly connected to the support frame 1, the connecting ring 32 of the support member 3 located on the side close to the front end cap 212 is fixedly connected to the front end cap 212, and the connecting ring 32 of the support member 3 located on the side close to the rear end cap 213 is fixedly connected to the rear end cap 213. The fixing ring 31 comprises a first ring body 311 and a second ring body 312 which are connected, the first ring body 311 and the second ring body 312 are arranged concentrically, the width of the second ring body 312 is smaller than that of the first ring body 311, the surface, close to the load machine 2, of the second ring body 312 protrudes out of the outer surface of the first ring body 311, and the first ring body 311 and the supporting seat are fixedly connected through bolts. Namely, the ring body one 311 close to the front support plate 11 and the front support plate 11 are fixedly connected to the mounting cavity 14 of the front support plate 11 through bolts, and the ring body one 311 close to the rear support plate 13 and the rear support plate 13 are fixedly connected to the mounting cavity 14 of the rear support plate 13 through bolts.

Referring to fig. 4 and 5, the connecting member 33 includes a connecting body 331, a first reinforcement body 332 and a second reinforcement body 333, one end of the first reinforcement body 332 is connected to the connecting body 331, and the other end is connected to the fixing ring 31, more specifically, the other end of the first reinforcement body 332 is fixedly connected to the second ring body 312, a side surface of the first reinforcement body 332 extending along the axial direction of the second ring body 312 is an arc-shaped surface, one end of the side surface is connected to an inner annular surface of the ring body, and the other end of the side surface is connected to a side surface of the connecting body 331, one end of the second reinforcement body 333 is connected to the connecting body 331, the other end of the second reinforcement body 333 is connected to the connecting ring 32, and a side surface of the second reinforcement body 333 extending along the axial direction of the connecting ring 32 is an arc-shaped surface, one end of the side surface is connected to a side surface of the connecting body 331, and the other end of the other end is connected to an outer annular surface of the connecting ring 32. Thus, the adjacent connectors 33 form the relief groove 35 therebetween. The second ring body 312, the connecting piece 33 and the connecting ring 32 are located on the same vertical plane near the loader 2.

In the using process, a motor shaft of the motor to be tested is connected with a motor shaft of the loading machine 2 through a coupler, then the motor to be tested works to drive the motor shaft of the loading motor to rotate, further drive the rotor 221 to rotate, and the electromagnetic torque of the loading machine 2 is simultaneously applied to the stator 222 and the rotor 221. The torque applied to the stator 222 is equal to and opposite to the torque applied to the rotor 221, so that the torque applied to the rotor 221 by the loading machine 2 can be measured by the stator 222, that is, by detecting the deformation of the stator 222 relative to the front support plate 11 and the rear support plate 13, the torque applied to the rotor 221 by the motor to be tested is the torque applied to the motor to be tested.

In this embodiment, when the stator 222 tends to rotate, the end cover is fixedly connected to the connection ring 32, the connection ring 32 is connected to the fixing ring 31 through the connection member 33, and the fixing ring 31 is fixedly connected to the support frame 1, so that the connection ring 32 rotates under the driving of the end cover, and the fixing ring 31 is fixedly connected to the support frame 1, so that the connection ring 32 deforms relative to the support frame 1, and the torque applied to the rotor 221 by the test loader 2 is achieved by detecting the deformation. That is, the connecting ring 32 drives the connecting shaft 41 to rotate, and the angular displacement sensor 42 detects the angular amount, which is converted into torque.

Since there are four connecting members 33 and the connecting members 33 are circumferentially arrayed between the connecting ring 32 and the fixed ring 31, the connecting strength of the connecting ring 32 and the fixed ring 31 is better, meanwhile, because the side surface of the first reinforcing body 332 extending along the axial direction of the second ring body 312 is an arc-shaped surface, one end of the side surface is connected with the inner ring surface of the second ring body 312, the other end is connected with the side surface of the connecting body 331, one end of the second reinforcing body 333 is connected with the connecting body 331, the other end is connected with the connecting ring 32, the side surface of the second reinforcing body 333 extending along the axial direction of the connecting ring 32 is an arc surface, one end of the side is connected with the side of the connector 331, the other end is connected with the outer circumferential surface of the connection ring 32, therefore, when the connecting ring 32 rotates, the stress at the joint of the second reinforcing body 333 and the connecting ring 32 can be effectively reduced due to the arc-shaped surface, and the probability of cracks at the joint of the connecting ring 32 and the second reinforcing body 333 after multiple uses is reduced.

Referring to fig. 4 and 5, in order to increase the connection strength between the first ring body 311 and the second ring body 312, the fixing ring 31 further includes a reinforcing ring 34, the reinforcing ring 34 includes a first reinforcing surface, a second reinforcing surface, a first inclined surface 341 and a first connecting surface, the first reinforcing surface is perpendicular to the second reinforcing surface, the second reinforcing surface is connected to the second ring body 312, the first reinforcing surface 311 is connected to the first ring body, one end of the first inclined surface 341 is connected to the first reinforcing surface through the first connecting surface, the other end of the first inclined surface 341 is connected to the second inclined surface, and the first inclined surface 341 is gradually close to the loader 2 in the direction of the center of the reinforcing ring 34. I.e. the reinforcement ring 34 has a right-angled trapezoidal shape in axial cross-section. Therefore, in the using process, the connecting strength between the first ring body 311 and the second ring body 312 is higher, and the ring is not easy to damage.

When the loading machine 2 is mounted on the supporting frame 1, the front cover 212 of the loading machine 2 is connected to the support 3 at the front supporting plate 11, more specifically, the front cover 212 is fixedly connected to the connecting ring 32 of the support 3, and the rear cover 213 of the loading machine 2 is connected to the support 3 at the rear supporting plate 13, more specifically, the rear cover 213 is fixedly connected to the connecting ring 32 of the support 3. In order to keep a good fixing effect on the loader 2, the loader 2 between the supports 3 is clamped by the supports 3, so that the connecting ring 32 is subjected to axial reaction force, the connecting ring 32 tends to move away from the loader 2, and the connecting ring 32 is connected with the second ring body 312 through the connecting piece 33, so that the second ring body 312 is also subjected to axial reaction force, and therefore the existence of the reinforcing ring 34, particularly the existence of the first inclined surface 341 can effectively reinforce the structural strength between the second ring body 312 and the first ring body 311, and reduce the probability of cracks at the connection position of the two.

Referring to fig. 2 and 3, in order to accelerate the heat dissipation of the load machine 2, the stator 222 is provided with heat dissipation holes 2111; the front support plate 11 is provided with a first wind guide flow passage 111 and a second wind guide flow passage 112, the first wind guide flow passage 111 is annular, and the first wind guide flow passage 111 is communicated with the gas flow passage 51. The first air guide flow channel 111 is also communicated with the heat dissipation hole 2111, the base 12 is provided with an air flow channel 121 and an air hole 131, the air hole 131 penetrates through the rear support plate 13, the air hole 131 is communicated with the air flow channel 121, and the air flow channel 121 is communicated with the second air guide flow channel 112.

Therefore, in the use process, the exhaust fan is communicated with the air hole 131, when the exhaust fan works, air enters the air flow passage 51 and the heat dissipation hole 2111 from the air hole 51 and is finally extracted after passing through the air guiding flow passage two 112 and the air guiding flow passage one 111, and therefore the stator 222 can be effectively cooled.

The air flow can also be blown into the air flow channel 121 from the air hole 131 by the fan, and flows to the second air guide flow channel 112 and the first air guide flow channel 111 through the air flow channel 121, and is finally discharged from the air hole 52 through the air flow channel 51 and the heat radiation hole 2111, thereby realizing the heat radiation of the stator 222. In this embodiment, since the shield 5 can protect the stator 222, and the heat dissipation hole 2111 is formed in the stator 222, the gas flow passage 51 is formed between the shield 5 and the stator 222, and the heat dissipation hole 2111, the gas flow passage 51, and the air hole 52 can maintain a good heat dissipation effect. The overall weight of the loader 2 is therefore smaller. The influence of the weight of the loader 2 on the connection ring 32 can be reduced, i.e. since the loader 2 is supported only by the support 3, the weight of the loader 2 is reduced, and the amount of deformation of the connection ring 32 in the vertical direction can be reduced, so that it is more accurate when measuring the torque.

The dynamometer provided by the embodiment of the application has the implementation principle that: when the motor is used, a motor shaft of a motor to be detected is connected with a motor shaft of the loading machine 2 through a coupler, then the motor to be detected rotates, then the motor shaft of the loading machine 2 rotates, further the stator 222 has a rotation trend, the connecting ring 32 rotates, the rotation angle of the connecting ring 32 is detected through the angular displacement sensor 42, and therefore the torque is obtained.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. The utility model provides a dynamometer, includes support frame (1), support frame (1) on be connected with load machine (2), load machine (2) including end cover, rotor (221) and stator (222), the end cover includes front end housing (212) and rear end housing (213), its characterized in that: the front end cover (212) is connected to one end of the stator (222), the rear end cover (213) is connected to the other end of the stator (222), a sensor and a support piece (3) are further arranged on the support frame (1), at least one end of the load machine (2) is connected with the support frame (1) through the support piece (3), the sensor is used for detecting the rotation amount of the stator (222), the support piece (3) comprises a connecting ring (32), a fixing ring (31) and a connecting piece (33), the connecting ring (32) and the fixing ring (31) are concentrically arranged, one end of the connecting piece (33) is connected with the connecting ring (32), the other end of the connecting piece is connected with the fixing ring (31), the fixing ring (31) is fixedly connected with the support frame (1), and the connecting ring (32) is connected with the end cover;

the sensor is an angular displacement sensor (42), and the angular displacement sensor (42) is used for detecting the rotation angle of the connecting ring (32);

the number of the connecting pieces (33) is at least two, and the connecting pieces (33) are circumferentially arrayed between the connecting ring (32) and the fixing ring (31).

2. The dynamometer machine of claim 1, characterized by: the connecting piece (33) comprises a connecting body (331), a first reinforcing body (332) and a second reinforcing body (333), one end of the first reinforcing body (332) is connected with the connecting body (331), the other end of the first reinforcing body is connected with the fixing ring (31), one end of the second reinforcing body (333) is connected with the connecting body (331), and the other end of the second reinforcing body is connected with the connecting ring (32).

3. A dynamometer according to claim 2, characterized in that: the fixing ring (31) comprises a first ring body (311) and a second ring body (312) which are connected, the first ring body (311) and the second ring body (312) are concentrically arranged, the width of the second ring body (312) is smaller than that of the first ring body (311), the surface, close to a load machine (2), of the second ring body (312) protrudes out of the outer surface of the first ring body (311), the first ring body (311) is fixedly connected with the support frame (1), and the second ring body (312) is fixedly connected with the first reinforcing body (332).

4. A dynamometer according to claim 3, characterized in that: the fixing ring (31) further comprises a reinforcing ring (34), the reinforcing ring (34) comprises a first reinforcing surface, a second reinforcing surface and a first inclined surface (341), the first reinforcing surface is perpendicular to the second reinforcing surface, the second reinforcing surface is connected with a second ring body (312), the first reinforcing surface is connected with the first ring body (311), one end of the first inclined surface (341) is connected with the first reinforcing surface, the other end of the first inclined surface is connected with the second inclined surface, and the first inclined surface (341) is gradually close to the loading machine (2) in the direction of the circle center of the reinforcing ring (34).

5. The dynamometer machine of claim 1, characterized by: the support frame (1) is provided with a protective cover (5), the protective cover (5) is provided with an air hole (52), the support frame (1) comprises a base (12), a front support plate (11) and a rear support plate (13) which are arranged at the two ends of the base (12), the front supporting plate (11) is positioned at one side of a front end cover (212) of the loading machine (2), the rear supporting plate (13) is positioned at one side of a rear end cover (213) of the loading machine (2), one end of the protective cover (5) is connected with the front supporting plate (11), the other end is connected with the rear supporting plate (13), the loading machine (2) is positioned in a cavity formed by the front support plate (11), the protective cover (5) and the rear support plate (13), the protective cover (5) and the stator (222) form a gas flow passage (51), and the gas flow passage (51) is communicated with the gas hole (52).

6. The dynamometer machine of claim 5, characterized by: and a first air guide flow passage (111) is arranged on the front support plate (11), and the first air guide flow passage (111) is communicated with the gas flow passage (51).

7. The dynamometer machine of claim 6, characterized by: the stator (222) is provided with heat dissipation holes (2111), and the heat dissipation holes (2111) are communicated with the first air guide flow channel (111).