CN116430073B - Gear speed sensor output frequency test circuit - Google Patents
Gear speed sensor output frequency test circuit Download PDFInfo
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- CN116430073B CN116430073B CN202211164954.7A CN202211164954A CN116430073B CN 116430073 B CN116430073 B CN 116430073B CN 202211164954 A CN202211164954 A CN 202211164954A CN 116430073 B CN116430073 B CN 116430073B
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- speed sensor
- output
- resistor
- gear speed
- test circuit
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- 238000012360 testing method Methods 0.000 title claims abstract description 27
- 230000003071 parasitic effect Effects 0.000 claims abstract description 13
- 238000001514 detection method Methods 0.000 claims abstract description 6
- 230000010355 oscillation Effects 0.000 claims description 4
- 229910000859 α-Fe Inorganic materials 0.000 claims description 3
- 239000003990 capacitor Substances 0.000 abstract description 6
- 238000000034 method Methods 0.000 abstract description 6
- 229910044991 metal oxide Inorganic materials 0.000 abstract 1
- 150000004706 metal oxides Chemical class 0.000 abstract 1
- 239000004065 semiconductor Substances 0.000 abstract 1
- 230000005540 biological transmission Effects 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000002620 method output Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P21/00—Testing or calibrating of apparatus or devices covered by the preceding groups
- G01P21/02—Testing or calibrating of apparatus or devices covered by the preceding groups of speedometers
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/72—Wind turbines with rotation axis in wind direction
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Transmission And Conversion Of Sensor Element Output (AREA)
- Measuring Magnetic Variables (AREA)
Abstract
The invention relates to an output frequency test circuit of a gear speed sensor, which comprises an oscillating circuit, a magnetic field alternating circuit and a speed sensor, wherein the magnetic field alternating circuit comprises a switch, a first boundary value frequency square wave output end and a second boundary value frequency square wave output end are respectively connected with two input ends of the switch, the output end of the switch is connected with one end of a second resistor, the other end of the second resistor is connected with a grid electrode of an MOS (metal oxide semiconductor) tube, a first resistor and a parasitic capacitor are connected in parallel between the grid electrode and a source electrode of the MOS tube, the first resistor is connected in parallel with the parasitic capacitor, the source electrode of the MOS tube is grounded, a drain electrode of the MOS tube is sequentially connected with a coil and positive power supply voltage in series, two ends of the coil are connected in parallel with a first diode, an anode of the first diode is connected with the drain electrode of the MOS tube, and a cathode of the first diode is connected with the positive power supply voltage. Compared with the prior art, the method has the advantages of safety, high efficiency, detection performance of the frequency boundary value by the test sensor and the like.
Description
Technical Field
The invention relates to output frequency test of a speed sensor, in particular to an output frequency test circuit of a gear speed sensor.
Background
In the process of designing the gear speed sensor, when it is required to verify whether the output of the test sensor meets square wave pulses in the frequency requirement range, the test of two boundary values is difficult. The gear speed sensor outputs square wave pulses by detecting a change in magnetic field intensity caused by alternation of tooth tops and tooth gaps of the moving gear. Taking boundary values of 0.1Hz and 20kHz as examples, if the modulus is 2 and the number of teeth is 120 during testing, the pitch circle diameter of the speed measuring gear is 240mm, and the output of 0.1Hz square wave pulse is equivalent to the rotation speed of the gear to be 0.05r/min, the motor can be burnt at low speed by utilizing the existing technology of driving the speed measuring gear by using a common motor, and if the rotation speed of the gear to be 0.05r/min can be realized by utilizing the low-speed motor through gear transmission, the transmission structure is too complex and has high cost; the output of 20kHz square wave pulse is 10000r/min, which is realized by complex and huge structural components such as the existing gears, drivers, mounting supports and the like, but has long manufacturing period, high cost and high danger coefficient when running. In summary, the structure of the boundary frequency value output by the current test sensor is complex, and the accuracy of the boundary values of the two frequencies, i.e. the highest frequency and the lowest frequency, of the sensor output cannot be safely tested.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, and provides an alternating safe and efficient gear speed sensor output frequency test circuit which simulates tooth tops and tooth gaps by utilizing the magnetic field change of an inductor.
The aim of the invention can be achieved by the following technical scheme:
the utility model provides a gear speed sensor output frequency test circuit, includes oscillation circuit, magnetic field alternating circuit and speed sensor, oscillation circuit includes first boundary value frequency square wave output and second boundary value frequency square wave output, magnetic field alternating circuit includes the switch, speed sensor is used for detecting magnetic field intensity variation, its characterized in that, two input of switch are connected respectively to first boundary value frequency square wave output and second boundary value frequency square wave output, and the one end of second resistance is connected to the output of switch, and the grid of MOS pipe is connected to the other end of second resistance, has first resistance and parasitic capacitance in parallel between the grid and the source of MOS pipe, first resistance and parasitic capacitance are parallelly connected, and the source of MOS pipe is grounded, and the drain electrode of MOS pipe is connected in series with coil and positive power supply voltage in proper order, the coil both ends are parallelly connected with first diode, and the positive electrode of first diode is connected with the drain electrode of MOS pipe, and the negative electrode of first diode is connected with positive power supply voltage.
Further, two ends of the second resistor are connected with a second diode in parallel, a cathode of the second diode is connected with an output end of the switch, and an anode of the second diode is connected with a grid electrode of the MOS tube.
Further, the head of the speed sensor is a hall element.
Further, the magnetic core of the coil is an I-shaped ferrite.
Further, the positive power supply voltage is connected to a power supply circuit.
Further, the input end of the oscillating circuit is connected with a power supply circuit.
Further, the resistance value of the first resistor is 40k omega-50 k omega.
Further, the resistance value of the first resistor is 43kΩ.
Further, the resistance value of the second resistor is 1k omega-10 k omega.
Further, the resistance value of the second resistor is 5.1kΩ.
Compared with the prior art, the invention has the following beneficial effects:
(1) Compared with the existing method for outputting square wave pulses by detecting the magnetic field intensity changes caused by the alternation of tooth tops and tooth gaps of the moving gears, the method has the advantages that the square wave electric signals with different frequencies are adopted to simulate different rotating speeds of the gears, the sensor is adopted to detect the changed magnetic field sent by the coil, the magnetic field intensity changes of the tooth tops and the tooth gaps of the moving gears are simulated by the changed magnetic field sent by the coil, and further the complex structure of the physical gears and the driving device thereof is avoided, the problem that whether a motor is burnt out or not is not needed to be considered when the low-frequency square wave pulses are tested, and the detection performance of the sensor to the frequency boundary value is safely and efficiently tested.
(2) Mature electronic components are adopted, a complex structure of a physical gear and a driving device thereof is omitted, and cost is saved.
Drawings
Fig. 1 is a circuit configuration diagram of the present invention.
Detailed Description
The invention will now be described in detail with reference to the drawings and specific examples. The present embodiment is implemented on the premise of the technical scheme of the present invention, and a detailed implementation manner and a specific operation process are given, but the protection scope of the present invention is not limited to the following examples.
Example 1:
the embodiment provides a gear speed sensor output frequency test circuit, as shown in fig. 1, including oscillating circuit U1, magnetic field alternating circuit and speed sensor, oscillating circuit U1 includes first boundary value frequency square wave output and second boundary value frequency square wave output, magnetic field alternating circuit includes switch S1, speed sensor is used for detecting magnetic field intensity variation, two input of switch S1 are connected respectively to first boundary value frequency square wave output and second boundary value frequency square wave output, the one end of second resistance R2 is connected to the output of switch S1, the grid of MOS pipe Q1 is connected to the other end of second resistance R2, first resistance R1 and parasitic capacitance Cgs have been parallelly connected between the grid and the source of MOS pipe Q1, the source of MOS pipe Q1 is grounded, the drain electrode of MOS pipe Q1 is connected in series with coil L1 and positive power supply voltage in proper order, the both ends of coil L1 are parallelly connected with first diode D1, the positive electrode of first diode D1 is connected with the drain electrode of MOS pipe Q1, first diode D1 is connected with positive power supply voltage.
When the accuracy of the detection of the first boundary value frequency square wave by the test sensor is selected, the switch S1 is connected and conducted with the first boundary value frequency square wave output end of the oscillating circuit U1, and the oscillating circuit U1 sends the first boundary value frequency square wave to the magnetic field alternating circuit. When the first boundary value frequency square wave is at a high level, the parasitic capacitor Cgs starts to be charged through the second resistor R2, after the voltage of the parasitic capacitor Cgs reaches a threshold value, the MOS tube Q1 enters a switch working state, the source electrode and the drain electrode of the MOS tube Q1 are saturated and conducted, an amplified voltage signal is output to the coil L1, and the coil L1 is charged.
When the first boundary value frequency square wave is at a low level, the parasitic capacitor Cgs discharges through the first resistor R1, after the voltage of the parasitic capacitor Cgs is lower than a threshold value, the MOS tube Q1 enters an off state, the coil L1 discharges through the first diode D1 connected in parallel at two ends, and the circuit damage caused by the overhigh voltage of the coil L1 is prevented.
The high level and the low level of the square wave signal are input to enable the MOS tube Q1 to be continuously turned on and turned off, the coil L1 is charged and discharged, the coil L1 generates variable current to generate variable magnetic fields, and the speed sensor outputs square waves through detecting the variable magnetic fields emitted by the coil L1. If the frequency difference between the square wave frequency output by the speed sensor and the square wave of the first boundary value frequency exceeds a certain threshold value, the speed sensor is indicated to have an error for detecting the square wave of the first boundary value frequency.
When the accuracy of the detection of the second boundary value frequency square wave by the test sensor is selected, the process of generating the varying magnetic field and the judgment of the speed sensor are the same as the accuracy of the detection of the first boundary value frequency square wave by the test sensor.
In some embodiments, two ends of the second resistor R2 are connected in parallel to a second diode D2, a cathode of the second diode D2 is connected to the output end of the switch S1, and an anode of the second diode D2 is connected to the gate of the MOS transistor Q1. When the square wave is at a low level, the parasitic capacitance Cgs discharges through the first resistor R1 and the second diode D2, and after the second diode D2 is added, the discharging speed of the parasitic capacitance Cgs is accelerated, the parasitic capacitance Cgs is faster lower than a threshold value, and the turn-off speed of the MOS tube Q1 is further accelerated.
The head of the speed sensor is a Hall element, and square wave pulses are output through the change of the magnetic field intensity. The existing method outputs square wave pulses through detecting the magnetic field intensity change caused by the alternation of tooth tops and tooth gaps of the moving gears, the motor is burnt out due to the fact that the speed is too low when square wave pulses with low frequency are generated, and the whole gear is complex in structure and high in risk coefficient when square wave pulses with high frequency are generated. According to the invention, by adopting square wave electric signals with different frequencies to simulate different rotating speeds of the gear, the changing magnetic field emitted by the coil L1 is detected, the magnetic field intensity changes of tooth tops and tooth gaps of the motion gear are simulated, square wave pulses are output, and the complex structure of the physical gear and a driving device thereof is avoided.
The magnetic core of the coil L1 is selected from I-shaped ferrite, so that the magnetic field is ensured to radiate to the surrounding space. If the speed sensor cannot detect the magnetic field change of the coil L1, the size of the coil L1 can be adjusted to enhance the magnetic field change of the coil L1.
In this embodiment, the positive supply voltage and the input of the oscillating circuit U1 are provided by the power supply circuit.
In this embodiment, the first and second boundary value frequencies are 0.1Hz and 20kHz, respectively.
In other embodiments, the first boundary value frequency and the second boundary value frequency may be set to other values.
In some embodiments, the first resistor R1 has a resistance of 40kΩ -50kΩ.
In some embodiments, the first resistor R1 has a resistance of 43kΩ.
In some embodiments, the second resistor R2 has a resistance of 1kΩ -10kΩ.
In some embodiments, the second resistor R2 has a resistance of 5.1kΩ.
The foregoing describes in detail preferred embodiments of the present invention. It should be understood that numerous modifications and variations can be made in accordance with the concepts of the invention by one of ordinary skill in the art without undue burden. Therefore, all technical solutions which can be obtained by logic analysis, reasoning or limited experiments based on the prior art by the person skilled in the art according to the inventive concept shall be within the scope of protection defined by the claims.
Claims (10)
1. The utility model provides a gear speed sensor output frequency test circuit, includes oscillation circuit (U1), magnetic field alternating circuit and speed sensor, oscillation circuit (U1) includes first boundary value frequency square wave output and second boundary value frequency square wave output, magnetic field alternating circuit includes switch (S1), speed sensor is used for detecting magnetic field intensity variation, its characterized in that, first boundary value frequency square wave output and second boundary value frequency square wave output connect respectively two input of switch (S1), the output of switch (S1) connects the one end of second resistance (R2), the other end of second resistance (R2) connects the grid of MOS pipe (Q1), connect in parallel between grid and the source of MOS pipe (Q1) first resistance (R1) and parasitic capacitance (Cgs), the source of MOS pipe (Q1) connects in parallel, the drain electrode of MOS pipe (Q1) connects in proper order with coil (L1) and positive power supply voltage, the positive electrode of two parallel connection of MOS pipe (Q1) and positive electrode (D1) are connected in series with the positive electrode voltage of two, the positive electrode of MOS pipe (Q1) is connected in parallel with the positive electrode of two ends of the first diode (D1);
the oscillating circuit (U1) outputs square waves to control the MOS tube (Q1) to be alternately turned on and turned off, the coil (L1) is alternately charged and discharged, the coil (L1) generates a changed current, the changed current generates a changed magnetic field, the speed sensor detects the changed magnetic field to output square waves, the square waves output by the speed sensor and the square waves output by the boundary value frequency square wave output end are compared to test the output frequency of the speed sensor, and the detection error of the speed sensor to the boundary value frequency is determined.
2. The output frequency test circuit of the gear speed sensor according to claim 1, wherein two ends of the second resistor (R2) are connected in parallel with a second diode (D2), a cathode of the second diode (D2) is connected with an output end of the switch (S1), and an anode of the second diode (D2) is connected with a gate of the MOS transistor (Q1).
3. The gear speed sensor output frequency test circuit of claim 1 wherein the head of the speed sensor is a hall element.
4. The output frequency test circuit of a gear speed sensor according to claim 1, wherein the magnetic core of the coil (L1) is an "i" shaped ferrite.
5. A gear speed sensor output frequency test circuit according to claim 1 wherein the positive supply voltage is connected to a power supply circuit.
6. A gear speed sensor output frequency test circuit according to claim 1, wherein the input of the oscillating circuit (U1) is connected to a power supply circuit.
7. A gear speed sensor output frequency test circuit according to claim 1, wherein the first resistor (R1) has a resistance value of 40kΩ -50kΩ.
8. A gear speed sensor output frequency test circuit according to claim 7, wherein the first resistor (R1) has a resistance of 43kΩ.
9. A gear speed sensor output frequency test circuit according to claim 1, wherein the second resistor (R2) has a resistance value of 1kΩ -10kΩ.
10. A gear speed sensor output frequency test circuit according to claim 9, wherein the second resistor (R2) has a resistance value of 5.1kΩ.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211164954.7A CN116430073B (en) | 2022-09-23 | 2022-09-23 | Gear speed sensor output frequency test circuit |
| PCT/CN2022/137592 WO2024060414A1 (en) | 2022-09-23 | 2022-12-08 | Gear speed sensor output frequency test circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211164954.7A CN116430073B (en) | 2022-09-23 | 2022-09-23 | Gear speed sensor output frequency test circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN116430073A CN116430073A (en) | 2023-07-14 |
| CN116430073B true CN116430073B (en) | 2023-11-10 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211164954.7A Active CN116430073B (en) | 2022-09-23 | 2022-09-23 | Gear speed sensor output frequency test circuit |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN116430073B (en) |
| WO (1) | WO2024060414A1 (en) |
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| CN110208564B (en) * | 2019-05-28 | 2024-04-02 | 南方科技大学 | Gear tooth type liquid metal rotating speed sensor and rotating speed measuring method |
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2022
- 2022-09-23 CN CN202211164954.7A patent/CN116430073B/en active Active
- 2022-12-08 WO PCT/CN2022/137592 patent/WO2024060414A1/en unknown
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Also Published As
| Publication number | Publication date |
|---|---|
| WO2024060414A1 (en) | 2024-03-28 |
| CN116430073A (en) | 2023-07-14 |
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