A visual teaching demonstration device for direct current brush motor

Abstract

The utility model belongs to the technical field of teaching demonstration device, disclose a kind of visual direct current brush motor teaching demonstration device, including base frame, rotor assembly, stator, carbon brush assembly and binding post;Base frame is frame structure, rotor assembly includes rotating shaft, commutator and rotor core, stator is symmetrically arranged in rotor core both sides and is wound excitation winding, carbon brush assembly and commutator are in contact and are connected external power supply by binding post.The utility model can directly show motor operating principle by frame structure, realize weak magnetic speed regulation, voltage-regulated speed and series resistance speed regulation three kinds of speed regulation mode, and support four excitation modes, such as shunt excitation, series excitation, compound excitation and it excitation connection.Solve the problem that the structure of existing teaching device is closed and demonstration is not intuitive, suitable for the teaching demonstration of direct current motor principle, with the characteristics of clear structure and simple operation.

Description

Technical Field

[0001] This utility model relates to the field of teaching demonstration devices, and in particular to a visual DC brushed motor teaching demonstration device. Background Technology

[0002] The operating principle, structural characteristics, and speed control methods of brushed DC motors are crucial for understanding motor control technology. However, current technology lacks brushed DC motor devices specifically designed for teaching purposes. Traditional DC motors typically employ a closed structure, and industrial-grade motors are large and have complex wiring, failing to meet teaching needs. Utility Model Content

[0003] The present invention aims to provide a visual teaching demonstration device for DC brushed motors to solve the problem that the lack of teaching demonstration tools makes it impossible to intuitively demonstrate the interaction between the commutator and armature.

[0004] To achieve the above objectives, this utility model provides the following technical solution:

[0005] The basic technical solution provided by this utility model is: a visual DC brushed motor teaching demonstration device, including a base frame and a rotor assembly. The base frame is a frame structure. The rotor assembly includes a rotating shaft rotatably connected to the base frame. The rotating shaft connects a commutator and a rotor core disposed inside the base frame. A pair of stators and a pair of carbon brush assemblies are connected inside the base frame. The pair of stators are mirror-symmetrically arranged on opposite sides of the rotor core with the vertical center plane of the base frame as the reference plane. The stators are wound with stator windings. The pair of carbon brush assemblies are mirror-symmetrically arranged on opposite sides of the commutator with the vertical center plane of the base frame as the reference plane. The commutator surface is provided with conductive copper foil. The rotor core is wound with rotor windings. The rotor windings and the copper foil are connected by electrical wires. The carbon brush assembly includes a carbon brush body connected to the base frame. The free end of the carbon brush body abuts against the copper foil on the outer surface of the commutator. The base frame is provided with terminals. The terminals are connected to the stator windings and the carbon brush body by electrical wires.

[0006] The principle of the basic technical solution is as follows: When the stator winding is energized, it generates a fixed magnetic field. When the rotor winding is energized in this magnetic field, it experiences electromagnetic force, generating torque. Carbon brushes, acting as stationary contacts, maintain contact with the rotating commutator. Through the conductivity of the carbon brushes, external current is conducted into the commutator, and then from there to the rotor winding. Simultaneously, the commutator and rotor rotate synchronously, working with the carbon brushes to achieve mechanical commutation. This timely change in the direction of the rotor winding current keeps the torque direction constant, thus achieving a continuous conversion of electrical energy into mechanical energy. Furthermore, the magnetic field strength depends on the number of turns and the current in the windings. Changing the external voltage changes the current. Voltage regulation and magnetic field strength regulation can be achieved by changing the number of turns in the stator and rotor windings or by changing the external voltage.

[0007] The beneficial effects of the basic technical solution are as follows: Based on the frame structure and the symmetrically arranged stator and carbon brush assemblies, the internal structure and working principle of the motor can be intuitively displayed, facilitating the observation of the dynamic contact process between the carbon brush and the commutator, as well as the magnetic field distribution; the carbon brush, as a stationary contact, maintains contact with the rotating commutator, realizing the function of external current introduction and mechanical commutation, and works with the commutator to change the direction of the rotor winding current in a timely manner, so that the torque direction remains constant; the exposed terminal design supports flexible connection, which facilitates experiments with different excitation methods and voltage regulation, effectively improving the teaching demonstration effect, and is particularly suitable for practical teaching of the working principle of DC brushed motors, helping students to deeply understand the entire process of electromagnetic conversion and mechanical commutation.

[0008] Preferably, the carbon brush assembly further includes a carbon brush frame connected to the base frame, a spring connected to the carbon brush frame, the free end of the spring being connected to a carbon brush connecting rod slidably connected to the carbon brush frame, and the end of the carbon brush connecting rod away from the spring being connected to the carbon brush body.

[0009] With the above configuration, the carbon brush assembly adopts a spring-loaded structure, which ensures a stable contact pressure between the carbon brush body and the commutator. This guarantees the reliability of current conduction and facilitates observation of the dynamic contact process between the carbon brush and the commutator. The spring applies elastic pressure through the carbon brush connecting rod, allowing the carbon brush body to adapt to the rotational movement of the commutator. Simultaneously, the sliding structure of the carbon brush connecting rod within the carbon brush frame makes pressure adjustment more stable and controllable.

[0010] Preferably, the carbon brush frame is provided with a sliding part, and the spring and carbon brush connecting rod are slidably disposed on the inner side of the sliding part.

[0011] With the above settings, the sliding part design of the carbon brush frame makes the movement of the spring and carbon brush connecting rod more stable and controllable, which not only ensures the uniformity of carbon brush pressure, but also makes it easier to observe the dynamic working process of the carbon brush assembly.

[0012] Preferably, the rotor core has three connecting arms, and the three connecting arms are evenly distributed around the rotating shaft.

[0013] With the above configuration, the three evenly distributed connecting arm structures enable the rotor core to have better dynamic balance performance, resulting in less vibration and more stable speed during operation.

[0014] Preferably, the stator winding is an excitation winding to generate a fixed magnetic field.

[0015] With the above setup, using the excitation winding as the stator winding, a stable and adjustable fixed magnetic field can be generated, making it easy to intuitively demonstrate the interaction principle between the magnetic field and the armature winding. Attached Figure Description

[0016] Figure 1 A schematic diagram of the overall structure of a visual teaching demonstration device for DC brushed motors;

[0017] Figure 2 This is a cross-sectional view of the overall structure of a visual DC brushed motor teaching demonstration device.

[0018] The names of the corresponding labels in the attached diagram are:

[0019] 1-Base frame, 2-Rotor assembly, 3-Stator, 4-Carbon brush assembly, 11-Terminal, 21-Commutator, 22-Rotor core, 23-Shaft, 41-Carbon brush body, 42-Carbon brush connecting rod, 43-Spring. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments:

[0021] like Figure 1 and Figure 2As shown, a visual DC brushed motor teaching demonstration device includes a base frame 1 and a rotor assembly 2. The base frame 1 is a frame structure. The rotor assembly 2 includes a rotating shaft 23 rotatably connected to the base frame 1. The rotating shaft 23 connects a commutator 21 and a rotor core 22 located inside the frame of the base frame 1. A pair of stators 3 and a pair of carbon brush assemblies 4 are connected inside the frame of the base frame 1. The pair of stators 3 are mirror-symmetrically arranged on opposite sides of the rotor core 22 with the vertical center plane of the base frame 1 as the reference plane. The stators 3 are wound with stator windings as excitation windings to generate a fixed magnetic field. The pair of carbon brush assemblies 4 are mirror-symmetrically arranged on opposite sides of the commutator 21 with the vertical center plane of the base frame 1 as the reference plane. The surface of the commutator 21 is decorated with... The rotor core 22 has three connecting arms evenly distributed around the rotating shaft 23, with rotor windings wound on the connecting arms. The rotor windings are connected to the copper foil via electrical wires. The carbon brush assembly 4 includes a carbon brush body 41 connected to the base frame 1. The free end of the carbon brush body 41 abuts against the copper foil on the outer surface of the commutator 21. The carbon brush assembly 4 also includes a carbon brush frame connected to the base frame 1. The carbon brush frame has a sliding part, and a carbon brush connecting rod 42 is slidably disposed in the sliding part. One end of the carbon brush connecting rod 42 is connected to the carbon brush body 41, and the other end is connected to a spring 43 disposed on the carbon brush frame. The base frame 1 has a terminal 11, which is connected to the stator windings and the carbon brush body 41 via electrical wires.

[0022] The specific implementation process is as follows:

[0023] In operation, the stator winding is wound around the stator 3, with both ends connected to terminals 11. The carbon brush body 41 is connected to the terminals 11 via wires. After connection, the power is turned on, and the stator winding generates a fixed magnetic field. Simultaneously, current flows through the carbon brush assembly 4 into the commutator 21 and is conducted to the rotor winding, causing the rotor core 22 to rotate under the influence of the magnetic field. During operation, it can be clearly observed that the carbon brush body 41 maintains contact with the rotating commutator 21 to achieve mechanical commutation, and the direction of the rotor winding current changes periodically with the rotation of the commutator, thereby maintaining a constant torque direction. The speed change pattern can be visually demonstrated by adjusting the power supply voltage or excitation current.

[0024] According to the working principle of the motor, the speed regulation function can be achieved in three ways when the rotor core 22 rotates: (1) Field weakening speed regulation: When the number of turns of the stator winding of the stator 3 is reduced while the number of turns of the rotor winding of the rotor core 22 remains unchanged, the magnetomotive force of the stator magnetic field decreases, resulting in a weakening of the magnetic field strength. At this time, the speed of the rotor core 22 increases; (2) Voltage regulation speed regulation: When the number of turns of the rotor winding of the rotor core 22 is reduced while the number of turns of the stator winding of the stator 3 remains unchanged, the induced voltage of the rotor winding decreases, resulting in an increase in the armature current. At this time, the speed of the rotor core 22 increases; (3) Series resistance speed regulation: When the number of turns of the stator winding and the rotor winding remains unchanged, a resistor is connected in series in the rotor winding circuit, which increases the total resistance of the armature circuit, resulting in a decrease in the armature current. At this time, the speed of the rotor core 22 decreases. These three speed regulation methods can be achieved by changing the connection method of the terminal 11, which can intuitively demonstrate the speed regulation principle of the DC brushed motor. In addition, by changing the connection method of the three sets of terminals, four different excitation modes of DC motors can be achieved: shunt excitation, series excitation, compound excitation, and separate excitation.

[0025] The above descriptions are merely embodiments of this utility model. Commonly known technical solutions or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solution of this utility model. These modifications and improvements should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A visual teaching demonstration device for DC brushed motors, characterized in that: The system includes a base frame (1) and a rotor assembly (2). The base frame (1) is a frame structure. The rotor assembly (2) includes a rotating shaft (23) rotatably connected to the base frame (1). The rotating shaft (23) connects a commutator (21) and a rotor core (22) located inside the frame of the base frame (1). A pair of stators (3) and a pair of carbon brush assemblies (4) are connected inside the frame of the base frame (1). The pair of stators (3) are mirror-symmetrically arranged on opposite sides of the rotor core (22) with the vertical center plane of the base frame (1) as the reference plane. The stators (3) are wound with stator windings. The pair of carbon brush assemblies (4) are... The vertical center plane of the base frame (1) is mirror-symmetrically arranged on opposite sides of the commutator (21) as a reference plane. The surface of the commutator (21) is provided with conductive copper foil. The rotor core (22) is wound with rotor windings. The rotor windings are connected to the copper foils by electrical wires. The carbon brush assembly (4) includes a carbon brush body (41) connected to the base frame (1). The free end of the carbon brush body (41) abuts against the copper foil on the outer surface of the commutator (21). The base frame (1) is provided with a terminal (11). The terminal (11) is connected to the stator windings and the carbon brush body (41) by electrical wires.

2. The visual DC brushed motor teaching demonstration device according to claim 1, characterized in that: The carbon brush assembly (4) also includes a carbon brush frame, which is connected to the base frame (1). A spring (43) is connected to the carbon brush frame. The free end of the spring (43) is connected to a carbon brush connecting rod (42) that is slidably connected to the carbon brush frame. The end of the carbon brush connecting rod (42) away from the spring (43) is connected to the carbon brush body (41).

3. The visual DC brushed motor teaching demonstration device according to claim 2, characterized in that: The carbon brush frame is provided with a sliding part, and the spring (43) and the carbon brush connecting rod (42) are slidably disposed on the inner side of the sliding part.

4. The visual DC brushed motor teaching demonstration device according to claim 1, characterized in that: The rotor core (22) is provided with three connecting arms, and the three connecting arms are evenly arranged around the rotating shaft (23).

5. The visual DC brushed motor teaching demonstration device according to claim 1, characterized in that: The stator winding is an excitation winding to generate a fixed magnetic field.

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