Balance experiment device of rigid rotor

Abstract

The invention belongs to the technical field of mechanical balance experiments, and particularly relates to a balance experiment device of a rigid rotor, which comprises a rotating shaft capable of being driven by a motor to rotate, a plurality of discs arranged on the rotating shaft, a plurality of counterweights and a power supply module for supplying power to the motor, a plurality of counter bores capable of accommodating counter weights are uniformly distributed on one side surface of the disc along the circumferential direction of the disc; and at least one disc is adjustably sleeved on the rotating shaft through the central hole of the disc. The balance experiment device of the rigid rotor is simple in structure, convenient to carry, low in cost and suitable for application and popularization; the rigid rotor balance experiment teaching aid is especially suitable for being used as a mechanical principle teaching aid and is used for demonstrating a rigid rotor balance experiment to students. When dynamic balance and dynamic unbalance experiments are carried out, students can hold the motor to feel vibration and experience dynamic balance and dynamic unbalance by themselves instead of watching demonstration only and incapable of generating personal feelings in traditional teaching, so that the teaching effect is better.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical balance experiments, and in particular relates to a balance experiment device for a rigid rotor. Background Art

[0002] At present, when students of mechanical related majors are learning the mechanical principles course, when teachers explain the balancing principle of rigid rotors, they usually give theoretical explanations. There are no simple and convenient experimental devices for carrying demonstrations. Students cannot have a personal experience and the teaching effect is not ideal.

[0003] For schools that have the conditions, the experimental devices used for demonstrations are also bulky and need to be demonstrated in special laboratories, which is costly and inconvenient for teaching. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the above-mentioned defects and provide a rigid rotor balancing experimental device, which has a simple structure, is easy to carry, has low cost, and is suitable for popularization and use; it is easy to operate and is particularly suitable for use as a teaching aid for mechanical principles to demonstrate rigid rotor balancing experiments to students.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: A rigid rotor balancing experimental device comprises a rotating shaft that can be driven to rotate by a motor, a plurality of discs arranged on the rotating shaft, a plurality of counterweights and a power supply module for supplying power to the motor; A plurality of countersunk holes capable of accommodating counterweights are evenly distributed along the circumference of the disc on one of the sides of the disc; At least one disc is adjustably mounted on the rotating shaft through its center hole.

[0006] Furthermore, the number of the countersunk holes on each disc is an even number, and the countersunk holes are arranged in pairs and centrally symmetrically on the disc.

[0007] Furthermore, a circle of protrusions is arranged along the edge of the disc on the other side surface of the disc.

[0008] Furthermore, the edge of the center hole extends axially to form a section of a hub sleeve, and the hub sleeve is provided with a countersunk through hole.

[0009] Furthermore, the rotating shaft is formed by plugging two shafts, the ends of the two shafts are respectively integrally formed with a disc, and the other disc is adjustably sleeved on the rotating shaft through the center hole thereof.

[0010] Furthermore, one end of the rotating shaft is integrally formed with a disc, and the other discs are adjustably sleeved on the rotating shaft through the center holes thereof.

[0011] Furthermore, all the discs are adjustably sleeved on the rotating shaft through their center holes, and a limiting convex edge is provided at one end of the rotating shaft.

[0012] Furthermore, the rotating shaft is prism-shaped.

[0013] Furthermore, the plurality of counterweights are all identical circular magnet blocks.

[0014] Furthermore, the power module supplies power to the motor after voltage transformation by the transformer.

[0015] Beneficial effects of the present invention: The rigid rotor balancing experimental device of the present invention has a simple structure, is easy to carry, has low cost, and is suitable for promotion and use; it is easy to operate, and is particularly suitable for use as a teaching aid for mechanical principles, and is used to demonstrate the balancing experiment of rigid rotors to students. When conducting dynamic balancing and dynamic unbalance experiments, students can hold the motor in their hands, and the motor drives the shaft to rotate, driving the disc rotor on the shaft to rotate. When there is dynamic unbalance, vibration will be generated, and the students' hands can feel the vibration, and they can personally experience dynamic balancing and dynamic unbalance, instead of traditional teaching where they can only watch the demonstration but cannot have a personal experience, and the teaching effect is better. In addition, the difference in vibration size can also be felt by adjusting the voltage or current. On the other hand, by operating the experimental device, students can also demonstrate the principle of mass substitution, making it easier for students to understand the principle of mass substitution, greatly improving the teaching effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide a preferred understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings: Figure 1 Schematic diagram of a balancing experimental device for a rigid rotor of this embodiment; Figure 2 is a schematic diagram of a disk in this embodiment; Figure 3 This is a schematic diagram of a first embodiment in which a disc and a rotating shaft are integrally formed; Figure 4 is a schematic diagram of another disc and a rotating shaft integrally formed in the first embodiment; Figure 5 yes Figure 3 and Figure 4 Schematic diagram of the two rotating shafts plug-in; Figure 6 is a schematic diagram of the assembly of the disc and the rotating shaft in the first embodiment; Figure 7 is a schematic diagram of a disc and a rotating shaft being integrally formed in the second embodiment; Figure 8 Schematic diagram of the rotating shaft in the third embodiment. DETAILED DESCRIPTION

[0017] The specific implementation of the present invention will be described below with reference to the accompanying drawings.

[0018] like Figure 1 As shown, this embodiment discloses a rigid rotor balancing experimental device, including a rotating shaft 1 that can be driven to rotate by a motor 5, a plurality of disks 2 arranged on the rotating shaft, a plurality of counterweights 3 and a power module 4.

[0019] like Figure 2 As shown, the disc is a homogeneous thin disc. On one side of the disc 2, a plurality of countersunk holes 21 are evenly distributed along the circumference of the disc, and the number of the countersunk holes is an even number, and the countersunk holes are arranged in pairs symmetrically on the disc 2. On the other side of the disc, a flange 22 is arranged along the edge of the disc.

[0020] At least one of the disks has a central hole 23 at its center that matches the shape of the outer wall of the shaft 1. Figure 2 The disc is sleeved on the rotating shaft 1 through the central hole 23, and its axial position relative to the rotating shaft can be adjusted arbitrarily.

[0021] In order to better adjust and fix the disc 2 on the rotating shaft 1, the edge of the central hole 23 of the disc extends axially to form a hub sleeve 24. The hub sleeve 24 is provided with a countersunk through hole 241. When screws and other components are installed in the countersunk through hole 241, they can pass through the countersunk through hole to push the rotating shaft in the hub sleeve, thereby limiting the relative position of the hub sleeve and the rotating shaft, so that the disc can be adjusted and fixed on the rotating shaft.

[0022] At most two other discs can be formed integrally with a shaft to serve as end discs, such as Figure 3 and Figure 4 shown.

[0023] The first embodiment is when two discs are integrally formed with a rotating shaft, and the two discs are end discs, such as Figure 3 and Figure 4 As shown, the two rotating shafts can be plugged together to form an integral rotating shaft, and the two plugged rotating shafts are fixed by screws inserted into the countersunk fixing holes 13 to limit axial movement, as shown in FIG. Figure 5 Other discs are discs with a central hole, such as Figure 2 As shown, the central hole is sleeved on the integral rotating shaft, and the assembled together form Figure 6 .

[0024] The second embodiment is when there is a disc formed integrally with the rotating shaft, the disc is used as the end disc, such as Figure 7 Other discs are discs with a central hole, such as Figure 2 As shown, it is sleeved on the rotating shaft 1 through the center hole.

[0025] The third embodiment is when no disc is integrally formed with the rotating shaft, and all discs 2 are discs with a central hole, such as Figure 2 As shown, they are all sleeved on the rotating shaft 1 through the center hole, such as Figure 8 As shown, preferably, a limiting flange 11 is provided at one end of the rotating shaft 1 to limit the position of the frontmost disc.

[0026] The shape and size of the counterweight 3 match the countersunk hole 21 on the disc, and the counterweight 3 can be installed in the countersunk hole 21 .

[0027] The counterweight is a circular strong magnetic magnet of the same type, used as an unbalanced or balanced mass. The counterweight applied at the same position on the disc is at least two magnets, one magnet is set in the countersunk hole 21, and the other magnet is set on the surface of the other side of the disc and attracts the magnet in the countersunk hole 21 across the disc. The magnet on the other side of the disc can be restricted on the disc by the convex edge 22 to prevent the centrifugal force when the disc rotates from throwing the magnet off the disc.

[0028] When more weight is needed at the same location on the disk, the additional magnets simply attach to the existing magnets at that location.

[0029] In order to increase the adsorption of the magnets on both sides of the disk and facilitate the removal of the magnets adsorbed together on both sides, a small through hole 211 smaller than the countersunk hole 21 is also provided in the countersunk hole, so that the magnet in the countersunk hole 21 and the magnet on the other side of the disk at this position can be better adsorbed together.

[0030] When the counterweight needs to be removed, since the magnet on the other side of the disc is located on the surface of the disc rather than in the countersunk hole, the magnet on the side can be removed by simply moving it along the surface of the disc to break away from the attraction of the magnet in the countersunk hole. At the same time, the magnet in the countersunk hole on the disc can also be removed smoothly because there is no magnetic attraction.

[0031] The rotating shaft 1 is a cylinder, preferably, Figure 8 As shown, the shaft 1 is a prism, and the center hole 23 of the disk is also set as a prism hole to prevent relative rotation between the disk and the shaft 1. The axis of the shaft 1 is provided with a mounting hole 12, through which the shaft can be mounted and fixed on the output shaft of the motor.

[0032] The size of the motor is suitable for holding in one hand. When conducting dynamic balancing and unbalancing experiments, students can hold the motor in their hands. The motor drives the shaft to rotate, driving the disc rotor on the shaft to rotate. When there is dynamic unbalance, vibration will be generated. Students can feel the vibration with their hands and experience the results of the experiment firsthand, instead of traditional teaching where they can only watch the demonstration but cannot experience it personally.

[0033] The motor 5 is powered by the power module 4. In this embodiment, the motor is a 24V DC motor.

[0034] The power module 4 can use 220V mains or a power bank to transform the voltage through a transformer 7 to power the motor. During teaching demonstrations, in order to facilitate the teacher to carry the experimental device, or in an operating environment where mains power is not required, a power bank can be used with a step-up transformer to step up the voltage to 24V to power the motor. If there is a mains power supply in an operating environment such as a laboratory, the 220V mains can be combined with a step-down transformer to step down the voltage to 24V to power the motor.

[0035] The motor speed can also be adjusted. The higher the speed, the more obvious the vibration. The vibration increases with the speed, and the students feel it more clearly and strongly when holding the motor.

[0036] A reducer 6 can also be arranged on the electric motor.

[0037] The motor speed can be adjusted by adjusting the voltage or current. Figure 1 As shown, in this embodiment, a voltage or current adjusting knob 71, 72 is provided on the transformer 7 to adjust the voltage or current output by the transformer to adjust the motor speed. A digital display screen 73 is also provided on the transformer 7 to display the current voltage or current output by the booster in real time, so that students can synchronously feel the vibration changes of the hand-held motor through the real-time display of the adjusted transformer output voltage or current during the experiment.

[0038] The principle of this experimental device is described as follows: When two disc rotors are mounted on a rotating shaft, a thin rotor is obtained when the ratio of the distance between the two outer end surfaces of the two discs to the diameter of the discs is less than 0.2. At this time, all the unbalanced masses of the rotors can be regarded as concentrated in the same plane.

[0039] When the ratio of the distance between the two outer end surfaces of the two disks to the diameter of the disks is greater than 0.2, a long rotor is obtained. At this time, the unbalanced masses of the rotor cannot be regarded as concentrated only in a certain plane.

[0040] When three or more disc rotors are mounted on a rotating shaft, a thin rotor is obtained when the ratio of the distance between the outermost end faces of the two outermost discs to the diameter of the discs is less than 0.2. At this time, all the unbalanced masses of the rotor can be regarded as concentrated in the same plane.

[0041] When the ratio of the distance between the outermost end surfaces of the two outermost disks to the diameter of the disk is greater than 0.2, a long rotor is obtained. At this time, the unbalanced masses of the rotor cannot be regarded as concentrated only in a certain plane.

[0042] The thin rotor and the long rotor can be used to demonstrate static imbalance and static balance, dynamic imbalance and dynamic balance respectively. The experimental device of the invention can be used as a teaching aid to demonstrate static imbalance and static balance, dynamic imbalance and dynamic balance, and let students personally experience dynamic balance and dynamic imbalance.

[0043] When a statically unbalanced rotor is placed flat on a smooth surface at any time, it will rotate, then rotate back and forth. When it stops swinging, the unbalanced mass must be directly below the rotor axis. When a statically balanced rotor is placed flat on a smooth surface at any time, the rotor will not rotate. At this time, the center of mass of the rotor is on the axis of the shaft. When a statically unbalanced thin rotor is installed on an electric motor, it is relatively stable at low speeds. When it rotates at high speeds, you can feel obvious vibrations when holding the motor. The vibration increases with the increase of speed. Such a rotor is dynamically unbalanced. When a statically balanced thin rotor is installed on an electric motor, it will be very stable regardless of whether it rotates at low or high speeds. You cannot feel the vibration when holding the motor. Such a rotor is dynamically balanced. When a statically unbalanced long rotor is installed on an electric motor, it is relatively stable at low speeds. When it rotates at high speeds, you can feel obvious vibrations when holding the motor. The vibration increases with the increase of speed. Such a rotor is dynamically unbalanced. For a statically balanced long rotor, if there are two unbalanced masses of the same size distributed in two disks far apart, and the line connecting the two unbalanced masses intersects with the axis of the rotor, and its center of mass is on the axis, such a long rotor is installed on the motor, it is relatively stable at low speeds, but when it rotates at high speeds, you can feel obvious vibrations when holding the motor, and the vibration increases with the increase of speed. Therefore, even if the long rotor is statically balanced, it may be dynamically unbalanced. A statically unbalanced long rotor is installed on the motor, it is relatively stable at low speeds, but when it rotates at high speeds, you can feel obvious vibrations when holding the motor, and the vibration increases with the increase of speed, indicating that such a rotor is also dynamically unbalanced.

[0044] The experimental device of the present invention can also be used as a teaching aid to demonstrate that the dynamic balancing of a thin rotor only requires single-sided balancing, that is, if there is an unbalanced mass on a certain disk of a long rotor, dynamic balancing can be achieved by adding a counterweight with the same weight as the unbalanced mass at a position symmetrical to the unbalanced mass on the disk or other disks.

[0045] The teaching aid of the present invention can also demonstrate that the dynamic balance of a long rotor requires double-sided balance and the calculation of mass substitution. Specifically, if the long rotor contains three discs, and the three discs are equidistant, if there are four magnets as unbalanced masses somewhere on the middle disc, then the method of dynamic balance is to add two magnets as counterweights to the two discs at both ends at positions symmetrical to the unbalanced masses. The long rotor is dynamically balanced and there is no vibration when it is driven by an electric motor to rotate at high speed. The principle is that the four magnets on the middle disc can be replaced by two magnets as unbalanced masses at positions corresponding to the unbalanced masses in the two discs at both ends using the principle of mass substitution. According to the principle of double-sided balance, it is only necessary to achieve static balance on the two planes at both ends. The method is to add balancing weights, that is, two magnets, at the symmetrical positions of the calculated unbalanced masses. Through the teaching demonstration of the experimental device, students can more easily understand the principle of mass substitution.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A balancing test device for a rigid rotor, characterized in that: It includes a rotating shaft that can be driven to rotate by a motor, a plurality of discs arranged on the rotating shaft, a plurality of counterweights and a power supply module for supplying power to the motor; On one side surface of the disc, a plurality of countersunk holes for accommodating counterweights are evenly distributed along the circumference of the disc; At least one disc is adjustably mounted on the rotating shaft through its center hole.

2. The rigid rotor balancing test device according to claim 1, characterized in that: The number of the countersunk holes on each disc is an even number, and the countersunk holes are arranged in pairs and centrally symmetrically on the disc.

3. The rigid rotor balancing test device according to claim 1, characterized in that: A circle of convex edges is arranged along the edge of the disc on the other side of the disc.

4. The rigid rotor balancing test device according to claim 1, characterized in that: The edge of the center hole extends axially to form a section of a hub sleeve, and the hub sleeve is provided with a countersunk through hole.

5. The rigid rotor balancing test device according to claim 1, characterized in that: The rotating shaft is formed by plugging two shafts, the ends of the two shafts are respectively formed integrally with a disc, and the other discs are adjustably sleeved on the rotating shaft through the center holes thereof.

6. The rigid rotor balancing test device according to claim 1, characterized in that: One end of the rotating shaft is integrally formed with a disc, and the other discs are adjustably sleeved on the rotating shaft through the center holes thereof.

7. The rigid rotor balancing test device according to claim 1, characterized in that: All the discs are adjustably sleeved on the rotating shaft through the central holes thereof, and a limiting convex edge is arranged at one end of the rotating shaft.

8. The rigid rotor balancing test device according to claim 1, 5, 6 or 7, characterized in that: The rotating shaft is in the shape of a prism.

9. The rigid rotor balancing test device according to claim 1, characterized in that: The plurality of counterweights are all identical circular magnet blocks.

10. The rigid rotor balancing test device according to claim 1, characterized in that: The power module supplies power to the motor after voltage transformation by the transformer.

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