Motor performance testing mechanism for nuclear magnetic resonance refrigerator

Abstract

The utility model discloses a motor performance testing mechanism for a nuclear magnetic resonance refrigerator, which comprises a testing frame, the testing frame is of a frame body structure with an upper layer and a lower layer, a tested motor is fixedly installed on one side of the upper surface of the lower layer of the testing frame through bolts, and an output shaft of the tested motor is connected with a first coupler. One end, far away from the tested motor, of the first coupling is fixedly connected with a torque sensor, the output end of the torque sensor is fixedly connected with a second coupling, and one end, far away from the torque sensor, of the second coupling is fixedly connected with load equipment. And meanwhile, the torque sensor can transmit a test value to the torque power meter, so that the output power information of the motor can be calculated through the torque power meter, the specific output power of the motor can be measured, the special performance test work of the cold head motor of the nuclear magnetic resonance refrigerator is completed, the test is convenient, and the use effect of rapid performance test is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of nuclear magnetic resonance refrigerators, in particular to a motor performance testing mechanism for nuclear magnetic resonance refrigerators. Background Art

[0002] The cold head is an important component of the magnetic resonance cooling system. Whether it operates normally directly affects the magnet pressure. The motor is one of the components of the cold head and is responsible for providing power to the cold head. During the maintenance of the cold head, it is often encountered that the motor makes abnormal noise due to insufficient power. At present, there is no special performance device for the cold head motor of the nuclear magnetic resonance refrigerator on the market, so there is inconvenience in testing. For this reason, the utility model proposes a motor performance testing mechanism for the nuclear magnetic resonance refrigerator. Utility Model Content

[0003] The purpose of the utility model is to provide a motor performance testing mechanism for a nuclear magnetic resonance refrigerator to solve the problems raised in the above background technology.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a motor performance testing mechanism for a nuclear magnetic resonance refrigeration machine, comprising a test frame, the test frame being a two-layer frame structure, the motor to be tested being fixedly installed on one side of the upper surface of the lower layer of the test frame by bolts, the output shaft of the motor to be tested being connected to a No. 1 coupling, the end of the No. 1 coupling away from the motor to be tested being fixedly connected to a torque sensor, the output end of the torque sensor being fixedly connected to a No. 2 coupling, and the end of the No. 2 coupling away from the torque sensor being fixedly connected to a load device.

[0005] Preferably, the torque sensor is a rotary torque sensor.

[0006] Preferably, the load device is a magnetic powder brake.

[0007] Preferably, a main control box is fixedly mounted on the upper surface of the superstructure of the test stand.

[0008] Preferably, a torque power meter and a magnetic powder controller are fixedly installed inside the master control box.

[0009] Preferably, the torque power meter is electrically connected to the torque sensor via a wire, and the magnetic powder controller is electrically connected to the load device via a wire.

[0010] Compared with the prior art, the beneficial effects of the present invention are:

[0011] The utility model can complete the performance test of the motor under test, and can accurately measure the torque and speed performance of the cold head motor. At the same time, the torque sensor can transmit the test value to the torque power meter, so that the output power information of the motor can be calculated through the torque power meter, thereby measuring the specific output power of the motor, completing the special performance test of the cold head motor of the nuclear magnetic resonance refrigerator, and judging whether the motor performance is qualified. The test is convenient and has the effect of rapid performance testing. In addition, the overall test structure of the utility model is simple, easy to install, uses less test equipment, has low test cost, and is suitable for popularization and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of the overall planar structure of the testing mechanism according to an embodiment of the present utility model;

[0013] Figure 2 This is a schematic diagram of the torque sensing working principle of the torque sensor according to an embodiment of the present utility model;

[0014] Figure 3 This is a schematic diagram of the speed sensing working principle of the torque sensor of an embodiment of the present utility model.

[0015] In the figure: 1. Test stand; 2. Motor under test; 3. Coupling No. 1; 4. Torque sensor; 5. Coupling No. 2; 6. Load device; 7. Main control box; 8. Torque power meter; 9. Magnetic powder controller. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0017] In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," "the other end," and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0018] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "provided with," "connected," etc. should be understood in a broad sense. For example, "connected" can mean a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be internal communication between two components. Those skilled in the art will be able to understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0019] See also Figure 1-3 The utility model provides an embodiment: a motor performance testing mechanism for a nuclear magnetic resonance refrigerator, including a test frame 1. The test frame 1 is a two-layer frame structure. A motor to be tested 2 is fixedly installed on one side of the upper surface of the lower layer of the test frame 1 by bolts. The output shaft of the motor to be tested 2 is connected to a No. 1 coupling 3. The end of the No. 1 coupling 3 away from the motor to be tested 2 is fixedly connected to a torque sensor 4. The output end of the torque sensor 4 is fixedly connected to a No. 2 coupling 5. The end of the No. 2 coupling 5 away from the torque sensor 4 is fixedly connected to a load device 6.

[0020] The torque sensor 4 is a rotary torque sensor. The torque sensing working principle of the rotary torque sensor is as shown in the appendix of the specification. Figure 2 As shown in the instruction manual Figure 2 As can be seen, the strain bridge is powered by an inductive voltage provided by a toroidal transformer, which is then converted into a DC voltage through rectification and voltage regulation. This voltage not only supplies the strain bridge with bridge voltage but also serves as the operating voltage for the internal circuit. The mV-level torque signal detected by the strain bridge is amplified to the V-level, converted into a proportional square wave signal by a V / F converter, and transmitted to an external receiver. It is then demodulated and restored to a digital signal, thereby measuring the working torque value of the motor 2 under test, completing the torque test of the motor.

[0021] Furthermore, the speed sensing working principle of the rotary torque sensor is as follows: Figure 3 As shown in the instruction manual Figure 3 It can be seen that the code disk is integrated with the rotating body and rotates. The photoelectric switch uses the photoelectric effect as a gate circuit to process and output high and low level pulse signals. The pulse signal is proportional to the speed, realizing the conversion of the physical quantity speed into an electrical signal, so that the speed value of the motor 2 under test can be measured, achieving the purpose of speed performance testing of the motor 2 under test;

[0022] The load device 6 is a magnetic powder brake. The voltage of the magnetic powder brake is 24V, the current is 1.5A, the torque is 24N·m, and the speed is 1400r / min. The working principle of the magnetic powder brake is described below:

[0023] The magnetic powder brake consists of a driving rotor (input shaft), a driven rotor (output shaft), and a magnetic yoke containing an excitation coil. These three parts are assembled concentrically to form a relatively rotatable whole. The annular gap (working chamber) between the main rotor and the driven rotor is filled with high-permeability magnetic powder (this is a prior art product).

[0024] When no current flows through the exciting coil, the magnetic powder in the working chamber is in a loose state. Under the action of the centrifugal force generated by the active rotor, the magnetic powder is evenly thrown onto the inner wall of the active rotor. There is no interaction between the active and driven rotors, the magnetic powder clutch is in a disengaged state, and no torque is transmitted.

[0025] When current flows through the excitation coil, a working magnetic flux is generated in the magnetic yoke, and the magnetic powder in the working chamber is quickly linked in a chain along the direction of the magnetic flux (forming a magnetic powder chain). The magnetic powder brake transmits torque by the friction between the magnetic powder and the magnetic powder, the magnetic powder and the working surface, and the shear resistance of the magnetic powder chain. The magnetic powder brake is in a coupled state.

[0026] When the current is cut off, the magnetic flux disappears as the excitation current disappears. The magnetic powder is loose again under the action of gravity and is thrown onto the inner wall of the active rotor under the action of centrifugal force. The magnetic powder brake is in a separated state again. It is used as a load structure in the utility model. The main function of the magnetic powder brake in the utility model is to control the torque of the rotating machinery and realize functions such as tension control, dynamometer loading and braking.

[0027] In this embodiment, a main control box 7 is fixedly installed on the upper surface of the upper structure of the test stand 1, and a torque power meter 8 and a magnetic powder controller 9 are fixedly installed inside the main control box 7;

[0028] In order to ensure normal control and data transmission, the torque power meter 8 is electrically connected to the torque sensor 4 through a wire, and the magnetic powder controller 9 is electrically connected to the load device 6, namely the magnetic powder brake, through a wire.

[0029] Working principle: When the utility model is used, the motor 2 to be tested can be installed on the test frame 1, and the output shaft of the motor 2 to be tested is connected to the No. 1 coupling 3. After the No. 1 coupling 3 is connected, the torque sensor 3, the No. 2 coupling 5 and the load device 6 are connected in sequence. Figure 1 As shown;

[0030] During the test, the output shaft of the motor 2 under test drives the torque sensor 4 to rotate through the No. 1 coupling 3. The torque sensor 4 is a rotary torque sensor. The torque sensing working principle of the rotary torque sensor is as shown in the attached manual. Figure 2 As shown in the instruction manual Figure 2As can be seen, the strain bridge is powered by an inductive voltage provided by a toroidal transformer, which is then converted into a DC voltage through rectification and voltage regulation. This voltage not only supplies the strain bridge with bridge voltage but also serves as the operating voltage for the internal circuit. The mV-level torque signal detected by the strain bridge is amplified to the V-level, converted into a proportional square wave signal by a V / F converter, and transmitted to an external receiver. It is then demodulated and restored to a digital signal, thereby measuring the working torque value of the motor 2 under test, completing the torque test of the motor.

[0031] The speed sensing working principle of the rotary torque sensor is as shown in the attached manual. Figure 3 As shown in the instruction manual Figure 3 It can be seen that the code disk is integrated with the rotating body and rotates. The photoelectric switch uses the photoelectric effect as a gate circuit to process and output high and low level pulse signals. The pulse signal is proportional to the speed, realizing the conversion of the physical quantity speed into an electrical signal, so that the speed value of the motor 2 under test can be measured, achieving the purpose of speed performance testing of the motor 2 under test;

[0032] The present invention is equipped with a load device 6, namely a magnetic powder brake, which is used as a load structure in the present invention. The main function of the magnetic powder brake in the present invention is to control the torque of the rotating machinery and realize functions such as tension control, dynamometer loading and braking.

[0033] In this way, the performance test of the motor 2 under test can be completed through the above-mentioned test structure and test method, and the torque and speed performance of the cold head motor can be accurately measured. At the same time, the torque sensor 4 can transmit the test value to the torque power meter 8, so that the output power information of the motor can be calculated through the torque power meter 8, thereby measuring the specific output power of the motor, and completing the special performance test of the cold head motor of the nuclear magnetic resonance refrigerator. The test is convenient and has the effect of rapid performance testing. The overall test structure of the utility model is simple, easy to install, uses less test equipment, and has low test cost, which is suitable for popularization and use.

[0034] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed within the present invention. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A motor performance testing mechanism for a nuclear magnetic resonance refrigerator, comprising a test stand (1), characterized in that: The test frame (1) is a frame structure with two layers, wherein a motor to be tested (2) is fixedly mounted on one side of the upper surface of the lower layer of the test frame (1) by means of bolts, the output shaft of the motor to be tested (2) is connected to a first coupling (3), the end of the first coupling (3) away from the motor to be tested (2) is fixedly connected to a torque sensor (4), the output end of the torque sensor (4) is fixedly connected to a second coupling (5), and the end of the second coupling (5) away from the torque sensor (4) is fixedly connected to a load device (6).

2. The motor performance testing mechanism for a nuclear magnetic resonance refrigerator according to claim 1, characterized in that: The torque sensor (4) is a rotational torque sensor.

3. The motor performance testing mechanism for a nuclear magnetic resonance refrigerator according to claim 1, characterized in that: The load device (6) is a magnetic powder brake.

4. The motor performance testing mechanism for a nuclear magnetic resonance refrigerator according to claim 1, characterized in that: A main control box (7) is fixedly mounted on the upper surface of the upper structure of the test stand (1).

5. The motor performance testing mechanism for a nuclear magnetic resonance refrigerator according to claim 4, characterized in that: A torque power meter (8) and a magnetic powder controller (9) are fixedly installed inside the master control box (7).

6. The motor performance testing mechanism for a nuclear magnetic resonance refrigerator according to claim 5, characterized in that: The torque power meter (8) is electrically connected to the torque sensor (4) via a wire, and the magnetic powder controller (9) is electrically connected to the load device (6) via a wire.

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