CN206194273U - Engine signal wheel sensor semi -physical simulation teaching system - Google Patents

Abstract

The utility model relates to a semi-physical simulation teaching system of an engine signal wheel sensor of the utility model, comprising a motor, a crankshaft position sensor, a camshaft position sensor, a potentiometer controller, an engine analyzer, a power supply, a support frame, and a signal plate 1, Signal plate 2, small pulley, large pulley, toothed belt, the motors are electrically connected to the potentiometer controller and the crankshaft position sensor respectively, the engine analyzer is electrically connected to the crankshaft position sensor and the camshaft position sensor respectively, and the power supplies are respectively It is electrically connected with the potentiometer controller and the camshaft position sensor; the support frame is connected with the signal plate 1, the signal plate 2, the small pulley, the large pulley, the crankshaft position sensor, and the camshaft position sensor, and the toothed belt is respectively connected with the small Pulley, large pulley connection. The utility model has strong demonstration function and structure display function, can truly restore the running condition of the engine signal wheel sensor, and the signal output conforms to the real condition of the engine running, and the timing is accurate.

Description

Engine signal wheel sensor semi-physical simulation teaching system

technical field

The utility model relates to a test system for simulating the operation of an engine, in particular to a semi-physical simulation teaching system for an engine signal wheel sensor.

Background technique

The signal wheel sensor is a representative sensor in the sensor. It is a sensor that converts the rotating speed signal into an electrical signal output. According to the test principle, it can be generally divided into Hall-type, magnetoelectric and photoelectric speed sensors. There are two types of signal wheel sensors used on the engine, one is the crankshaft position sensor, and the other is the camshaft position sensor, which is an extremely important sensor in the electronic control system of the engine. Hall type or magnetoelectric type are mostly used. Both sensors are sensors triggered by the signal wheel. The relationship between the camshaft position signal and the crankshaft position signal is that the crankshaft rotates twice, the camshaft signal rotor rotates once, and the crankshaft position signal rotor rotates twice. The engine computer will judge the working stroke of the cylinder and control it according to the signals of the two sensors. Ignition advance timing, fuel injection timing and fuel injection pulse width, so its output signal directly affects the accuracy of ignition timing, fuel injection timing and VVT control, thus affecting engine power, fuel economy and emission cleanliness. Therefore, it is of great significance for maintenance technicians to master the structure, working principle and signal output characteristics of the sensor for vehicle fault diagnosis.

The principle and application of sensors is a professional basic course for science and engineering students, and its teaching content is closely related to experiments. At present, one of the sensor teaching instruments on the market is a physical system on the engine bench, and the other is controlled by a motor driver. Some products use a DSP controller to control the motor speed, and the measurement and control accuracy can basically be satisfied. The former cannot see the structure of the sensor, and the engine runs during the measurement and reading of the signal, resulting in waste of resources and environmental pollution. The latter is a display of the structure and working principle of a single sensor, which cannot well show the two Sensor signal relationship.

Utility model content

The purpose of this utility model is to provide a semi-physical simulation teaching system for engine signal wheel sensors, which has a strong demonstration function and structure display function, and also has a signal waveform measurement function of the sensor, which is helpful for engineering and technical personnel to master the sensor structure, work The principle and signal output can truly restore the operation of the engine signal wheel sensor, and the signal output conforms to the real situation of the engine operation, and the timing is accurate.

In order to achieve the above object, the utility model has the following technical solutions:

A semi-physical simulation teaching system for an engine signal wheel sensor of the utility model includes a motor, a crankshaft position sensor, a camshaft position sensor, a potentiometer controller, an engine analyzer, a power supply, a support frame, a signal plate 1, a signal plate 2, The small pulley, the large pulley, and the toothed belt, the motors are electrically connected to the potentiometer controller and the crankshaft position sensor respectively, the engine analyzer is electrically connected to the crankshaft position sensor and the camshaft position sensor respectively, and the power supply is respectively connected to the potentiometer control The device and the camshaft position sensor are electrically connected; the support frame is connected with the signal plate one, the signal plate two, the small pulley, the large pulley, the crankshaft position sensor, and the camshaft position sensor, and the toothed belt is connected with the small pulley and the large pulley respectively. The pulley is connected; the potentiometer controller controls the motor speed by controlling the voltage output, and the speed range is 0-3640 rpm; the motor directly drives the crankshaft position sensor to rotate, because the crankshaft speed and the cam The shaft speed is 2:1, so the crankshaft position sensor is driven by the small pulley and the large pulley, and the transmission ratio is 2:1 to drive the camshaft sensor to rotate, and the engine analyzer is installed on the signal test channel 1 and channel 2 Connect to the signal output terminals of the crankshaft position sensor and the camshaft position sensor respectively, and obtain the signal output characteristics of the two sensors respectively. By changing the output voltage of the potentiometer controller and simulating the engine operation, different operating speeds can be obtained, so you can see different Signal output characteristics at speed.

Wherein, the crankshaft position sensor includes a sensor lead wire, a permanent magnet, an air gap one, a convex tooth, and a signal wheel one. The signal wheel one is located under the permanent magnet, the air gap one is located between the signal wheel one and the permanent magnet, and the protruding teeth are at the edge of the signal wheel one.

Wherein, the camshaft position sensor includes an impeller, a signal wheel 2, a permanent magnet, a Hall element, and an air gap 2, the signal wheel 2 is connected to the permanent magnet, the air gap 2 is located between the signal wheel and the Hall element, and the impeller On the edge of signal wheel two.

Owing to having taken above technical scheme, the utility model has the advantage that:

Compared with the traditional welding device, the utility model:

1. It has a strong demonstration function and structure display function, as well as a sensor signal waveform measurement function, which helps engineers and technicians to master the sensor structure, working principle and signal output.

2. The test bench uses a motor instead of an engine to run, reducing air pollution, and realizes motor speed regulation with a power supply, and the speed regulation range is 0-3640 rpm.

3. The operation of the engine signal wheel sensor is truly restored, and the signal output conforms to the real situation of the engine operation, and the timing is accurate.

Description of drawings

Fig. 1 is the schematic block diagram of the utility model system;

Fig. 2 is the schematic diagram of the utility model structure;

Fig. 3 is the structural representation of crankshaft position sensor of the present utility model;

Fig. 4 is the structural representation of the utility model camshaft position sensor;

Fig. 5 is the output signal waveform diagram of the camshaft position sensor and the camshaft position sensor of the utility model at an idle speed of 760 rpm;

Fig. 6 is the output signal waveform diagram of the camshaft position sensor and the camshaft position sensor under the condition of 1800 rpm of the utility model;

Fig. 7 is the output signal waveform diagram of the camshaft position sensor and the camshaft position sensor under the condition of 3450 rpm of the utility model;

Fig. 8 is a waveform diagram of the output signal of the camshaft position sensor and the camshaft position sensor of the utility model at the maximum speed of 3640 rpm.

In the figure: 1 motor, 2 support frame, 3 small pulley, 4 camshaft position sensor, 5 signal plate, 6 toothed belt, 7 large pulley, 8 signal plate, 9 crankshaft position sensor, 1-1 sensor lead wire, 2-1 permanent magnet, 3-1 air gap 1, 4-1 convex teeth, 5-1 signal wheel 1, 1-2 impeller, 2-2 signal wheel 2, 3-2 permanent magnet, 4-2 Hall element , 5-2 air gap two; U-CH1 channel 1, U-CH2 channel 2.

detailed description

The following examples are used to illustrate the utility model, but not to limit the scope of the utility model.

Referring to accompanying drawings 1-8, a kind of semi-physical simulation teaching system of engine signal wheel sensor of the present utility model, comprises motor, crankshaft position sensor, camshaft position sensor, potentiometer controller, engine analyzer, power supply, support frame, signal Disc 1, signal disc 2, small pulley, large pulley, and toothed belt, the motors are electrically connected to the potentiometer controller and the crankshaft position sensor respectively, and the engine analyzer is electrically connected to the crankshaft position sensor and the camshaft position sensor respectively , the power supply is electrically connected to the potentiometer controller and the camshaft position sensor respectively; Connect with the small pulley and the large pulley respectively; the potentiometer controller controls the motor speed by controlling the voltage output, and the speed range is 0-3640 rpm; the motor directly drives the crankshaft position sensor to rotate, because the simulated engine is actually During operation, the crankshaft speed and the camshaft speed are in a 2:1 relationship, so the crankshaft position sensor is driven by the small pulley and the large pulley, and the transmission ratio is 2:1. The rotation drives the camshaft sensor to rotate, and the engine analyzer Install the signal test channel 1 and channel 2 to connect to the crankshaft position sensor and camshaft position sensor signal output terminals respectively, and obtain the signal output characteristics of the two sensors respectively. By changing the output voltage of the potentiometer controller and simulating the engine operation, different operations can be obtained. Speed, so you can see the signal output characteristics at different speeds.

The crankshaft position sensor includes a sensor lead wire, a permanent magnet, an air gap 1, a convex tooth, and a signal wheel 1. The sensor lead wires are respectively a signal line, a signal ground, and a shielding line, and the signal line is connected to a coil on the permanent magnet. The signal wheel one is located under the permanent magnet, the air gap one is located between the signal wheel one and the permanent magnet, and the protruding teeth are at the edge of the signal wheel one.

The crankshaft position sensor consists of a permanent magnet core and an electromagnetic coil outside the core to form the core element. Its structural principle is shown in Figure 3. There are three wirings for the sensor, signal line, signal ground, and shielding line.

The signal wheel is a toothed disc type, and 58 convex teeth, 57 small teeth and a large tooth gap are evenly spaced on the circumference. The arc occupied by the large tooth gap is equivalent to the arc occupied by two convex teeth and 3 small tooth gaps. , the large tooth gap outputs the reference signal, corresponding to the position of the compression top dead center of the simulated engine cylinder 1 or cylinder 4, which is used to judge the crankshaft speed and crankshaft angle signal. Since the air gap between the rotor convex teeth and the permanent magnet directly affects the reluctance of this circuit and the output voltage of the induction coil, the air gap between the convex teeth and the permanent magnet is generally designed to be 0.2-0.4mm. The performance parameters and technical specifications of the crankshaft position sensor are shown in Table 1.

Table 1 Performance parameters and technical specifications of the magnetoelectric crankshaft position sensor

The camshaft position sensor includes an impeller, a second signal wheel, a permanent magnet, a Hall element, and an air gap two. The second signal wheel is connected to the permanent magnet, and the second air gap is located between the signal wheel and the Hall element. on the edge of wheel two.

The camshaft position sensor has a compact structure, few main components and simple assembly process. The structural principle of the camshaft position sensor is shown in Figure 4. The signal wheel 2 is also called the signal trigger impeller. When the impeller on the signal wheel 2 passes through the Hall element, it outputs a low level. When it leaves the Hall element, it outputs a high level. Its function is to accurately sense and detect the operation of the simulated engine when the camshaft is running. During the process, the relative rotation angle position is provided to the ECU in the form of a voltage signal, which is convenient for the ECU to combine the signal of the crankshaft position sensor to correctly determine the working phase of each cylinder of the engine at that moment, so that the system can control the fuel injection and firing order. This allows for more precise control of the engine's combustion process and reduces harmful combustion emissions. The camshaft position sensor uses three lead wires, one is the power wire for the engine computer power supply, the other is the sensor power wire, and the other is the ground wire. The performance parameters and technical specifications of the camshaft position sensor are shown in Table 2.

Table 2 Hall-type camshaft position sensor performance parameters and technical specifications

Design and selection of transmission components:

The motor is a small low-voltage DC motor, the MY6812A motor produced by Shenzhen Yijufeng Technology Co., Ltd., with a working voltage of 12v, a no-load speed of 3800, an output power of 100W, and a daily operating time of no more than 4 hours. The crankshaft position sensor and The camshaft position sensor is a very important sensor to realize the engine ignition timing, fuel injection timing and reduce pollutant emissions. It must be driven synchronously, and the transmission ratio i=2. Because the toothed belt has low noise, low cost and reliable operation , small elongation, high transmission accuracy and other characteristics, which meet the performance requirements of the test bench. Select the model of the toothed belt according to the transmitted power and speed and in combination with the actual situation, and finally determine the bandwidth and the number of teeth and structural parameters of the pulley as follows.

Timing belt model: 60XL025;

Number of small pulley teeth: 16;

The pitch circle diameter of the small pulley is 25.87mm;

Large pulley teeth: 32;

Large pulley pitch circle diameter: 51.74mm;

Bandwidth 6.4mm;

Center distance: 100mm.

DC motor speed control:

When the motor adopts a DC motor, the DC motor can be divided into four types according to the different excitation methods: separately excited, shunt excited, series excited and compound excited. Different excitation methods have different mechanical characteristic curves of DC motors. For a DC motor, the artificial mechanical characteristic equation is:

In the formula: the ideal no-load speed of n ₀ motor, its value is

Δn is the speed difference;

U _a voltage is the armature power supply (V);

R _a is the total resistance of the armature circuit (Ω);

φ is the excitation flux (Wb);

C _E is the electric potential coefficient;

C _T torque coefficient;

T is time.

It can be seen from the formula that to adjust the motor speed, the armature resistance R _a , the armature voltage U _a and the excitation flux φ must be changed, but the smooth stepless speed regulation can be realized by changing the armature voltage speed regulation, and the speed regulation is stable , large speed range and so on. Therefore, the utility model adopts the potentiometer controller to divide the voltage to change the armature voltage so as to change the motor speed. The B10K potentiometer controller produced by Beijing Longdian Motor Co., Ltd. is used to control the motor speed, and the voltage regulation range is 0-12V.

Performance experiment of hardware-in-the-loop simulation system:

Connect the power supply SPD-400-XX provided by Changzhou Shuobo Electronics to the utility model system. The power supply has a 12V dual output power supply, which provides reliable power supply for the motor and the camshaft position sensor respectively. Use the engine analyzer produced by Bosch Nanjing Auto Parts Co., Ltd., model FSA740, to read the output signal waveforms of the sensors at different speeds of the motor. Channel 1 collects the output waveform of the crankshaft position signal, and channel 2 collects the signal waveform of the camshaft position. The crankshaft position sensor, cam The signal output system test of the shaft position sensor is shown in Figure 1, and the output signal waveform is shown in Figure 5-8. From Figure 5-8, it can be seen that the crankshaft position sensor rotates twice, and the camshaft position sensor rotates once. In simulating the engine crankshaft magnetoelectric sensor, the basic signal output by the large tooth and missing tooth corresponds to the low level of the camshaft output. At this time It is the signal of 1-cylinder compression top dead center, and the test verification shows that the speed range of the signal test bench is 0-3640 rpm, and the signal output meets the signal output characteristics of the simulated engine and meets the design requirements.

Power supply: Connect the power supply SPD-400-XX provided by Changzhou Shuobo Electronics to the experimental bench. The power supply has dual output power supply, which provides reliable power supply for the motor and Hall sensor respectively.

Motor: Choose a small low-voltage DC motor, the MY6812A motor produced by Shenzhen Yijufeng Technology Co., Ltd., with a working voltage of 12v, a no-load speed of 3800, an output power of 100W, and a daily operating time of no more than 4 hours.

Potentiometer controller: This system uses potentiometer voltage division to change the armature voltage to change the motor speed. The B10K potentiometer controller produced by Beijing Longdian Motor Co., Ltd. is used to control the motor speed, and the voltage adjustment range is 0-12V.

ECU (Electronic Control Unit) electronic control unit, also known as "driving computer", "vehicle computer" and so on. In terms of use, it is a microcomputer controller for automobiles, also called a single-chip microcomputer for automobiles. It is the same as an ordinary single-chip microcomputer, consisting of a microprocessor (CPU), memory (ROM, RAM), input/output interface (I/O), analog-to-digital converter (A/D), and large-scale integrated circuits such as shaping and driving. composition.

VVT variable valve timing technology is to adjust the intake and exhaust volume and time by controlling the opening angle of the intake valve to advance and delay under specific engine conditions, and to change the size of the valve overlap angle to increase the intake charge. Quantity and efficiency, better organization of intake vortex, adjustment of cylinder explosion pressure and residual exhaust gas volume, to obtain comprehensive performance improvement of engine power, torque, emission, fuel economy, comfort, etc., so as to solve the traditional fixed valve timing engine The technical contradictions that restrict each other among the various performance indicators.

The engine signal wheel sensor of the utility model is an important sensor for realizing engine timing, improving engine performance and reducing emissions. The diagnostic instrument collects its output signal, and the result shows that the output signal conforms to the signal output law of the sensor when the engine is working. Moreover, the system has a strong demonstration function and structure display function, which is helpful for engineers and technicians to master the sensor structure, working principle and signal output

Apparently, the above-mentioned embodiments of the present utility model are only examples for clearly illustrating the present utility model, rather than limiting the implementation manner of the present utility model. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. All the implementation manners cannot be exhaustively listed here. All obvious changes or variations derived from the technical solutions of the utility model are still within the scope of protection of the utility model.

Claims (3)

1. a kind of engine signal wheel sensor HWIL simulation tutoring system, it is characterised in that：Passed including motor, crank position Sensor, CMPS Camshaft Position Sensor, potentiometer controller, engine analyzer, power supply, support frame, signal panels one, signal panels 2nd, small pulley, big belt wheel, cog belt, the motor are electrically connected with potentiometer controller, crankshaft position sensor respectively, are started Machine analyzer is electrically connected with crankshaft position sensor, CMPS Camshaft Position Sensor respectively, power supply respectively with potentiometer controller, convex Wheel shaft position sensor electrical connection；Support frame as described above and signal panels one, signal panels two, small pulley, big belt wheel, crank position sensing Device, CMPS Camshaft Position Sensor connection, cog belt are connected with small pulley, big belt wheel respectively；The potentiometer controller is by control Voltage output processed, controlled motor rotating speed, 0-3640 revs/min of speed adjustable range；Motor directly drives crankshaft position sensor to rotate, by Speed of crankshaft and camshaft speed are 2 during the engine real-world operation simulated：1 relation, so by bent axle position Put the small pulley of sensor, big belt wheel transmission to drive, gearratio is 2:1 rotational band moving cam axle sensor is rotated, hair Motivational research instrument installs signal testing passage 1 and passage 2 is connected respectively to crankshaft position sensor and CMPS Camshaft Position Sensor Signal output part, respectively obtains two signal output characteristics of sensor, by changing potentiometer controller output voltage, simulation Engine operating just obtains different running speeds, therefore can see the signal output characteristic in the case of different rotating speeds.

2. according to a kind of engine signal wheel sensor HWIL simulation tutoring system described in claim 1, it is characterised in that： The crankshaft position sensor includes sensor lead, permanent magnet, air gap, double wedge, signal wheel, the sensor lead difference It is holding wire, signal ground and shielding line, the holding wire is connected with the coil on permanent magnet, the signal wheel is located at permanent magnetic Iron lower section, air gap is located between signal wheel and permanent magnet, and the double wedge is in the edge of signal wheel.

3. according to a kind of engine signal wheel sensor HWIL simulation tutoring system described in claim 1, it is characterised in that： The CMPS Camshaft Position Sensor includes impeller, signal wheel, permanent magnet, Hall element, air gap, the signal wheel and permanent magnetic Iron is connected, and air gap is located between signal wheel and Hall element, and impeller is on the edge of signal wheel.