A position calibration system for long-stroke automobile clutch

Abstract

The technical solution adopted by the present invention is: a position calibration system for a long-stroke automobile clutch, comprising two Hall chips, a permanent magnet and a microprocessor unit; the permanent magnet is fixed on the automobile clutch; when the clutch is at the zero position, the Hall chip is symmetrically fixed inside the vehicle outside the permanent magnet; the signal output end of the Hall chip is electrically connected to the signal input end of the microprocessor unit; the permanent magnet undergoes linear displacement with the clutch and triggers the two Hall chips to output linear signals; the microprocessor unit receives the linear signals output by the two Hall chips, and fits the two linear signals to obtain a comprehensive linear signal; the displacement data of the automobile clutch is obtained through the comprehensive linear signal. The present invention saves costs and effectively improves the position calibration accuracy of the clutch.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile clutches, and in particular relates to a position calibration system for a long-stroke automobile clutch. Background Art

[0002] The clutch position sensor is located above the vehicle clutch bracket. The clutch position sensor is the clutch switch. The sensor transmits the clutch position signal to the ECU controller for controlling the cruise control (GRA) and the ignition angle and fuel injection amount during gear shifting.

[0003] At present, the position calibration of automobile clutch usually adopts PLCD sensor due to the long stroke. PLCD is the abbreviation of Permanent-magnet linear contactless displacement, that is, permanent magnet linear non-contact displacement sensor. Its working principle is to bond and fix the permanent magnet on the automobile clutch. The sensor is composed of a magnetic iron core, a primary coil and two secondary coils wound thereon respectively. When the primary coil generates an excitation AC voltage of a certain frequency, a corresponding inductive electromotive force will be generated on the two secondary coils. When the permanent magnet moves linearly, the difference between the output voltages of the two secondary coils is linearly related to the movement of the permanent magnet.

[0004] Existing sensors have a complex structure and high manufacturing cost. They need to be matched with special chips to generate excitation AC voltage. The magnetic field will produce hysteresis effect in the iron core, affecting accuracy and response time. Summary of the invention

[0005] The purpose of the present invention is to solve the deficiencies of the above-mentioned background technology and to provide a position calibration system for a long-stroke automobile clutch, which can save costs and effectively improve the position calibration accuracy of the clutch.

[0006] The technical solution adopted by the present invention is: a position calibration system for a long-stroke automobile clutch, comprising two Hall chips, a permanent magnet and a microprocessor unit; the permanent magnet is fixed on the automobile clutch; when the clutch is at the zero position, the Hall chip is symmetrically fixed inside the whole vehicle outside the permanent magnet; the Hall chips are distributed along the movement direction of the permanent magnet; the signal output end of the Hall chip is electrically connected to the signal input end of the microprocessor unit; the permanent magnet undergoes linear displacement with the clutch and triggers the two Hall chips to output linear signals; the microprocessor unit receives the linear signals output by the two Hall chips, and fits the two linear signals to obtain a comprehensive linear signal; the displacement data of the automobile clutch is obtained through the comprehensive linear signal.

[0007] In the above technical solution, the two Hall chips and the microprocessor unit are fixed on the same PCB board; the signals output by the two Hall chips are PWM duty cycle signals. The present invention integrates the Hall chip and the microprocessor unit on the PCB, effectively saving space in the vehicle. In the above technical solution, the Hall chip located on the left side of the permanent magnet is the first chip, and the signal output by the first chip is the first signal, and the first output signal depends on the relative position of the permanent magnet and the first chip; the Hall chip located on the right side of the permanent magnet is the second chip, and the signal output by the second chip is the second signal, and the second output signal depends on the relative position of the permanent magnet and the second chip; except for any moment when the clutch is at the zero position, the relative position of the permanent magnet and the first chip and the second chip is different; the first signal and the second signal output by the first chip and the second chip at any moment are different. The present invention obtains the position data of the permanent magnet more accurately by setting the two Hall chips relative to each other.

[0008] The process in which the microprocessing unit receives the linear signals output by the two Hall chips and fits the two linear signals to obtain a comprehensive linear signal includes:

[0009] The microprocessing unit determines whether the first signal and the second signal are effectively outputted linearly;

[0010] If both the first signal and the second signal are effectively outputted in a linear manner, a linear fitting process is performed on the first signal and the second signal to obtain a comprehensive linear signal;

[0011] If only the first signal is effectively outputted in a linear manner, only the first signal is linearly processed to obtain a comprehensive linear signal;

[0012] If only the second signal is effectively outputted in a linear manner, only the second signal is linearly processed to obtain a comprehensive linear signal.

[0013] The present invention only processes and calculates the effective linear output signal, thereby ensuring the effectiveness and accuracy of the calculated integrated linear signal.

[0014] In the above technical solution, the process of the microprocessing unit determining whether the first signal and the second signal are effectively outputted linearly includes:

[0015] If the first signal is less than or equal to the first set value, it is determined that only the first signal is effectively outputted linearly;

[0016] If the first signal is greater than or equal to the second set value, it is determined that only the second signal is effectively outputted linearly;

[0017] If the first signal is greater than the first set value and less than the second set value, it is determined that both the first signal and the second signal are effectively output linearly.

[0018] The present invention defines a first set value and a second set value for a first signal to determine whether the signal is effectively output linearly, thereby improving the efficiency of the determination process and saving calculation costs.

[0019] In the above technical solution, the following formula is used to perform linear fitting processing on the first signal S1 alone to obtain a comprehensive linear signal S:

[0020] S = C*S1+D1 (1);

[0021] Wherein C is the set calculation coefficient, and D1 is the set first compensation value.

[0022] In the above technical solution, the following formula is used to perform linear fitting processing on the signal S2 alone to obtain a comprehensive linear signal S:

[0023] S = C*S2+D2 (2);

[0024] Wherein C is the set calculation coefficient, and D2 is the set second compensation value.

[0025] In the above technical solution, the following formula is used to perform linear fitting processing on the first signal and the second signal to obtain a comprehensive linear signal S:

[0026] S=(C*S1+D1)*1 / 2+(C*S2+D2)*1 / 2 (3).

[0027] The present invention adopts a set formula to perform linear fitting processing on the signal to obtain a comprehensive signal, thereby improving the calculation efficiency while ensuring the calculation accuracy, and effectively reflecting the stroke state of the clutch.

[0028] In the above technical solution, the first compensation value D1, the second compensation value D2 and the calculation coefficient C are obtained by experimental calculation in the laboratory; the whole process from the clutch being fully closed to being fully separated is simulated in the laboratory, during which the first chip and the second chip output the first signal and the second signal to the microprocessing unit in real time, and the position data of the clutch at each moment in the whole process are collected at the same time; the stroke of the clutch in the whole process is L;

[0029] Get the high saturation threshold S of the first signal in the whole process max The second signal has a low saturation threshold S in the whole process. min ;

[0030] Find the high saturation threshold S of the first signal max The clutch position corresponding to the starting point is taken as the first signal saturation position point;

[0031] Find the lower saturation threshold S of the second signal min The clutch position corresponding to the end point is used as the second signal saturation position point;

[0032] Obtaining an absolute value of a difference between a second signal saturation position point and a first signal saturation position point as a saturation position difference Δ;

[0033] The first compensation value D1 is calculated using the following formula:

[0034] D1=S min *(L-Δ) / (2*L) (4);

[0035] The second compensation value D2 is calculated using the following formula:

[0036] D2=S max *(L-Δ) / (2*L) (5);

[0037] The calculation coefficient C is calculated using the following formula:

[0038] C = (L + Δ) / (2*L) (6).

[0039] The present invention obtains all coefficients in the formula for calculating the comprehensive linear signal through laboratory test data. The calculation method of the above coefficients effectively reflects the stroke characteristics and state of the clutch, and effectively ensures the accuracy of the calculation of the comprehensive linear signal.

[0040] In the above technical solution, the first set output value A and the second set output value B are obtained through laboratory test calculations; by setting the output values ​​A and B, it is helpful to determine the linear interval of the first signal S1 and the second signal S2, which facilitates further linear fitting comprehensive output.

[0041] The first set position point P1 is obtained using the following formula:

[0042] P1 = Δ / 4 (7);

[0043] The second set position point P2 is obtained using the following formula:

[0044] P2 = -Δ / 4 (8);

[0045] The first set value A is the output value of the first signal corresponding to the first set position point P1 during the whole process; the second set value B is the output value of the first signal corresponding to the second set position point P2 during the whole process.

[0046] The present invention obtains the first set value and the second set value through laboratory test data, effectively reflects the stroke characteristics and state of the clutch, and effectively ensures the accuracy of the comprehensive linear signal calculation.

[0047] In the above technical scheme, the whole process from full closure to full separation of the clutch is simulated in the laboratory, and the displacement data of the clutch at each moment in the whole process is collected at the same time; and the comprehensive linear signal at each moment in the whole process is calculated based on the first signal and the second signal output by the first chip and the second chip in the whole process by using formulas (1)-(8); the linear relationship between the clutch position data and the comprehensive linear signal data at each moment in the whole process is calculated; the microprocessing unit can calibrate the position stroke of the clutch based on the comprehensive linear signal obtained in real time and its linear relationship with the clutch position data. The present invention effectively improves the measurement position stroke of the sensor by using a dual Hall chip, develops a special algorithm and implants it into the microprocessor, realizes the comprehensive linear fitting output of the two output signals, improves the output accuracy of the sensor, and can meet the requirements of clutch position calibration.

[0048] The beneficial effects of the present invention are as follows: the present invention eliminates the PLCD sensor in the prior art, which has a complex structure and requires a special chip to generate an AC excitation voltage. In addition, since an iron core is required, a hysteresis effect is inevitably generated, thereby affecting the accuracy and response time of the sensor. The present invention adopts a structure in which a single magnet and a double chip are matched, which has a simple structure and is easy to manufacture and install. The present invention simultaneously develops a corresponding calculation method to obtain a relatively ideal linear output that changes with the stroke, effectively improving the measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is the installation schematic diagram of the present invention;

[0050] Figure 2 is a circuit diagram of the present invention;

[0051] Figure 3 It is a schematic diagram of the process of the present invention;

[0052] Figure 4 It is a schematic diagram of the output signal of the dual chip of the present invention;

[0053] Figure 5 It is a schematic diagram of the output signal of the dual chip of the present invention and the fitted linear signal. DETAILED DESCRIPTION

[0054] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments to facilitate a clear understanding of the present invention, but they do not constitute a limitation on the present invention.

[0055] like Figure 1As shown, the present invention provides a position calibration system for a long-stroke automobile clutch, comprising two Hall chips, a permanent magnet and a microprocessor unit; the permanent magnet is fixed on the automobile clutch; the Hall chip is symmetrically fixed inside the vehicle outside the permanent magnet when it is in the zero position; the signal output end of the Hall chip is electrically connected to the signal input end of the microprocessor unit; the permanent magnet undergoes linear displacement with the clutch and triggers the two Hall chips to output linear signals; the microprocessor unit receives the linear signals output by the two Hall chips, and fits the two linear signals to obtain a comprehensive linear signal; the displacement data of the automobile clutch is calibrated by the comprehensive linear signal. The permanent magnet is bonded and fixed on the automobile clutch and performs a long-stroke linear motion therewith. The microprocessor unit calibrates the position stroke of the clutch by measuring the movement of the permanent magnet through two Hall chips.

[0056] like Figure 2 As shown, the two Hall chips and the microprocessor unit are fixed on the same PCB board; the signals output by the two Hall chips are PWM duty cycle signals.

[0057] Specifically, the Hall chip located on the left side of the permanent magnet is the first chip, and the signal output by the first chip is the first signal, and the first output signal depends on the relative position of the permanent magnet and the first chip; the Hall chip located on the right side of the permanent magnet is the second chip, and the signal output by the second chip is the second signal, and the second output signal depends on the relative position of the permanent magnet and the second chip; except for any moment when the clutch is at the zero position, the relative positions of the permanent magnet, the first chip, and the second chip are different; the first signal and the second signal output by the first chip and the second chip at any moment are not the same. The permanent magnet moves between the first chip and the second chip with the clutch. When the clutch is at zero point, the two chips are symmetrical relative to the magnet, but the positions are different, for example, one is +10mm and the other is -10mm. Because the magnetic field is a vector and has a direction, when the chips are symmetrical (+10mm, -10mm), the magnetic signals detected by the two chips are also different. The microprocessor unit integrates an independently developed algorithm program, which fits two linear signals to obtain a comprehensive linear signal, such as Figure 3 Shown include:

[0058] The microprocessing unit determines whether the first signal S1 and the second signal S2 are effectively outputted linearly;

[0059] If both the first signal S1 and the second signal S2 are invalid, an error message indicating that the output signal is invalid is displayed. This situation is generally very rare.

[0060] If the first signal S1 and the second signal S2 are both effectively outputted in a linear manner, the first signal and the second signal are subjected to linear fitting processing to obtain a comprehensive linear signal S;

[0061] If only the first signal S1 is effectively outputted in a linear manner, only the first signal S1 is linearly processed to obtain a comprehensive linear signal S;

[0062] If only the second signal S2 is effectively outputted in a linear manner, only the second signal S2 is linearly processed to obtain a comprehensive linear signal S.

[0063] Specifically, the process of the microprocessing unit determining whether the first signal and the second signal are effectively outputted linearly includes:

[0064] If the first signal S1 is less than or equal to the first set value A, it is determined that only the first signal S1 is effectively outputted linearly; the following formula is used to perform linear fitting processing on the first signal S1 alone to obtain a comprehensive linear signal S:

[0065] S = C*S1+D1 (1);

[0066] Wherein C is the set calculation coefficient, and D1 is the set first compensation value.

[0067] If the first signal S1 is greater than or equal to the second set value B, it is determined that only the second signal S2 is effectively outputted linearly; the following formula is used to perform linear fitting processing on the signal S2 alone to obtain a comprehensive linear signal S:

[0068] S = C*S2+D2 (2);

[0069] Wherein C is the set calculation coefficient, and D2 is the set second compensation value.

[0070] If the first signal S1 is greater than the first set value A and less than the second set value B, it is determined that the first signal S1 and the second signal S2 are both effectively outputted linearly; the first signal and the second signal are fitted linearly using the following formula to obtain a comprehensive linear signal S:

[0071] S=(C*S1+D1)*1 / 2+(C*S2+D2)*1 / 2 (3).

[0072] Specifically, the first compensation value D1, the second compensation value D2, the calculation coefficient C, the first set value A and the second set value B are obtained by experimental calculation in the laboratory: the whole process from the clutch being fully closed to being fully separated is simulated in the laboratory, and the first chip and the second chip output the first signal and the second signal to the microprocessing unit in real time during the whole process; the microprocessing unit calculates the first signal and the second signal collected during the whole process to obtain the first compensation value D1, the second compensation value D2 and the calculation coefficient C, and the process is as follows:

[0073] like Figure 4 As shown, the high saturation threshold S of the first signal in the whole process is obtained. maxThe second signal has a low saturation threshold S in the whole process. min ; The high saturation threshold S of the first signal in the whole process max is the value corresponding to the inflection point of the first signal from continuous linear climbing to the first flat period; the low saturation threshold S of the second signal in the whole process min It is the value corresponding to the inflection point where the second signal enters a continuous linear climbing stage from a flat period.

[0074] Find the high saturation threshold S of the first signal max The clutch (permanent magnet) position corresponding to the starting point is taken as the first signal saturation position point and stored as Δ / 2;

[0075] Find the lower saturation threshold S of the second signal min The clutch (permanent magnet) position corresponding to the end point is stored as the second signal saturation position point as -Δ / 2;

[0076] Obtaining an absolute value of a difference between a second signal saturation position point and a first signal saturation position point as a saturation position difference Δ;

[0077] The first compensation value D1 is calculated using the following formula:

[0078] D1=S min *(L-Δ) / (2*L) (4);

[0079] The second compensation value D2 is calculated using the following formula:

[0080] D2=S max *(L-Δ) / (2*L) (5);

[0081] The calculation coefficient C is calculated using the following formula:

[0082] C = (L + Δ) / (2*L) (6).

[0083] The first set position point P1 is obtained using the following formula:

[0084] P1 = Δ / 4 (7);

[0085] The second set position point P2 is obtained using the following formula:

[0086] P2 = -Δ / 4 (8);

[0087] like Figure 5 As shown, the first set value A is the output value of the first signal corresponding to the first set position point P1 in the whole process; the second set value B is the output value of the first signal corresponding to the second set position point P2 in the whole process.

[0088] Preferably, the whole process from full closure to full separation of the clutch is simulated in the laboratory, and the displacement data of the clutch at each moment in the whole process is collected; the first compensation value D1, the second compensation value D2, the calculation coefficient C, the first set value A and the second set value B are calculated by statistical analysis in the microprocessing unit using formulas (4)-(8), and the built-in algorithm program of the microprocessing unit is generated.

[0089] The algorithm program integrated in the microprocessor unit is as follows:

[0090]

[0091]

[0092] Based on the first signal S1 and the second signal S2 output by the first chip and the second chip in the whole process, and the built-in algorithm program of the microprocessing unit, the comprehensive linear signal S at each moment in the whole process is calculated.

[0093] According to the clutch displacement data and the integrated linear signal data at each moment in the whole process, the linear relationship between the clutch position data and the integrated linear signal data is calculated, and the linear relationship is configured in the microprocessor unit as an algorithm program.

[0094] In the actual application of this specific embodiment, the microprocessing unit obtains the first signal output by the first chip and the second signal output by the second chip in real time. The microprocessing unit determines whether the first signal and the second signal are effectively output linearly:

[0095] If the first signal S1 is less than or equal to the first set value A, it is determined that only the first signal S1 is effectively outputted linearly; the following formula is used to perform linear fitting processing on the first signal S1 alone to obtain a comprehensive linear signal S:

[0096] S = C*S1+D1 (1);

[0097] Wherein C is the set calculation coefficient, and D1 is the set first compensation value.

[0098] If the first signal S1 is greater than or equal to the second set value B, it is determined that only the second signal S2 is effectively outputted linearly; the following formula is used to perform linear fitting processing on the signal S2 alone to obtain a comprehensive linear signal S:

[0099] S = C*S2+D2 (2);

[0100] Wherein C is the set calculation coefficient, and D2 is the set second compensation value.

[0101] If the first signal S1 is greater than the first set value A and less than the second set value B, it is determined that the first signal S1 and the second signal S2 are both effectively outputted linearly; the first signal and the second signal are fitted linearly using the following formula to obtain a comprehensive linear signal S:

[0102] S=(C*S1+D1)*1 / 2+(C*S2+D2)*1 / 2 (3).

[0103] The microprocessing unit can calibrate the clutch position stroke based on the comprehensive linear signal obtained in real time and its linear relationship with the clutch position data.

[0104] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. A position calibration system for a long-stroke automobile clutch, characterized in that: The invention comprises two Hall chips, a permanent magnet and a microprocessor unit; the permanent magnet is fixed on the automobile clutch; when the clutch is at the zero position, the Hall chip is symmetrically fixed inside the whole vehicle outside the permanent magnet; the Hall chips are distributed along the movement direction of the permanent magnet; the signal output end of the Hall chip is electrically connected to the signal input end of the microprocessor unit; the permanent magnet undergoes linear displacement along with the clutch and triggers the two Hall chips to output linear signals; the microprocessor unit receives the linear signals output by the two Hall chips, and fits the two linear signals to obtain a comprehensive linear signal; the displacement data of the automobile clutch is obtained through the comprehensive linear signal; The Hall chip located on the left side of the permanent magnet is the first chip, and the signal output by the first chip is the first signal, and the first output signal depends on the relative position of the permanent magnet and the first chip; the Hall chip located on the right side of the permanent magnet is the second chip, and the signal output by the second chip is the second signal, and the second output signal depends on the relative position of the permanent magnet and the second chip; at any time except when the clutch is at the zero position, the relative positions of the permanent magnet and the first chip and the second chip are different; the first signal and the second signal output by the first chip and the second chip at any time are different; The process in which the microprocessing unit receives the linear signals output by the two Hall chips and fits the two linear signals to obtain a comprehensive linear signal includes: The microprocessing unit determines whether the first signal and the second signal are effectively outputted linearly; If both the first signal and the second signal are effectively outputted in a linear manner, a linear fitting process is performed on the first signal and the second signal to obtain a comprehensive linear signal; If only the first signal is effectively outputted in a linear manner, only the first signal is linearly processed to obtain a comprehensive linear signal; If only the second signal is effectively outputted in a linear manner, only the second signal is linearly processed to obtain a comprehensive linear signal; The first signal S1 is linearly fitted using the following formula to obtain a comprehensive linear signal S: S = C*S1+D1 (1); Where C is the set calculation coefficient, and D1 is the set first compensation value; The following formula is used to perform linear fitting processing on the signal S2 alone to obtain the comprehensive linear signal S: S = C*S2+D2 (2); Where C is the set calculation coefficient, and D2 is the set second compensation value; The first signal and the second signal are linearly fitted using the following formula to obtain a comprehensive linear signal S: S=(C*S1+D1)*1 / 2+(C*S2+D2)*1 / 2 (3); The first compensation value D1, the second compensation value D2 and the calculation coefficient C are obtained by experimental calculation in the laboratory; the whole process from the clutch being fully closed to being fully separated is simulated in the laboratory, during which the first chip and the second chip output the first signal and the second signal to the microprocessor unit in real time, and the position data of the clutch at each moment in the whole process are collected at the same time; the stroke of the clutch in the whole process is L; Get the high saturation threshold S of the first signal in the whole process max The second signal has a low saturation threshold S in the whole process. min ; Find the high saturation threshold S of the first signal max The clutch position corresponding to the starting point is taken as the first signal saturation position point; Find the lower saturation threshold S of the second signal min The clutch position corresponding to the end point is used as the second signal saturation position point; Obtaining an absolute value of a difference between a second signal saturation position point and a first signal saturation position point as a saturation position difference Δ; The first compensation value D1 is calculated using the following formula: D1 = Smin*(L-Δ) / (2*L) (4); The second compensation value D2 is calculated using the following formula: D2 = Smax*(L-Δ) / (2*L) (5); The calculation coefficient C is calculated using the following formula: C = (L + Δ) / (2*L) (6).

2. A position calibration system for a long-stroke automobile clutch according to claim 1, characterized in that: The two Hall chips and the microprocessor unit are fixed on the same PCB board; the signals output by the two Hall chips are PWM duty cycle signals.

3. The position calibration system for a long-stroke automobile clutch according to claim 1, characterized in that: The process of the microprocessing unit determining whether the first signal and the second signal are effectively outputted linearly includes: If the first signal is less than or equal to the first set value, it is determined that only the first signal is effectively outputted linearly; If the first signal is greater than or equal to the second set value, it is determined that only the second signal is effectively outputted linearly; If the first signal is greater than the first set value and less than the second set value, it is determined that both the first signal and the second signal are effectively output linearly.

4. A position calibration system for a long-stroke automobile clutch according to claim 3, characterized in that: The first setting value A and the second setting value B are obtained by laboratory test calculation; The first set position point P1 is obtained using the following formula: P1 = Δ / 4 (7); The second set position point P2 is obtained using the following formula: P2 = -Δ / 4 (8); The first set value A is the output value of the first signal corresponding to the first set position point P1 in the whole process; The second set value B is the output value of the first signal corresponding to the second set position point P2 in the whole process.

5. A position calibration system for a long-stroke automobile clutch according to claim 4, characterized in that: The whole process from full closure to full separation of the clutch is simulated in the laboratory, and the displacement data of the clutch at each moment in the whole process is collected; and the comprehensive linear signal at each moment in the whole process is calculated based on the first signal and the second signal output by the first chip and the second chip in the whole process using formulas (1)-(8); Based on the clutch displacement data and the integrated linear signal data at each moment in the entire process, the linear relationship between the clutch position data and the integrated linear signal data is calculated; the microprocessing unit can calibrate the clutch position stroke based on the integrated linear signal obtained in real time through its linear relationship with the clutch position data.

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