A gear ratio detection device for a rack and pinion steering system

Abstract

The utility model relates to a kind of transmission ratio detection devices of gear rack steering system, including rotational speed sensor, first frequency voltage conversion module, speed sensor, second frequency voltage conversion module and division operation module;The output end of the rotational speed sensor is connected the input end of the first frequency voltage conversion module, and the output end of the first frequency voltage conversion module is connected the dividend signal input end of the division operation module;The output end of the speed sensor is connected the input end of the second frequency voltage conversion module, and the output end of the second frequency voltage conversion module is connected the divisor signal input end of the division operation module;The division operation module is used to output transmission ratio signal;The utility model is by using two frequency voltage conversion modules respectively with rotational speed sensor and speed sensor output frequency signal conversion into voltage signal, then two voltage signals are compared, to obtain the real-time transmission ratio of gear rack.

Description

Technical Field

[0001] This utility model relates to the field of vehicle steering technology, specifically to a transmission ratio detection device for a rack and pinion steering system. Background Technology

[0002] For rack and pinion steering systems, the transmission ratio is calculated using the design parameters of the gears and racks. However, during vehicle operation, the real-time transmission ratio cannot be obtained solely based on the design transmission ratio. In existing technologies, the transmission ratio is mainly estimated by predicting whether the transmission slips through the steering system's operating conditions. However, the estimated transmission ratio cannot reflect the actual transmission ratio of the rack and pinion transmission mechanism, making it impossible to determine whether the vehicle steering system is at risk of failure. Utility Model Content

[0003] To address the technical problem that existing technologies cannot reflect the actual transmission ratio of rack and pinion transmission mechanisms, thus making it impossible to determine whether a vehicle steering system is at risk of failure, this utility model provides a transmission ratio detection device for rack and pinion steering systems.

[0004] The technical solution of this utility model to solve the above-mentioned technical problems is as follows: A transmission ratio detection device for a rack and pinion steering system includes a first voltage conversion module, a speed sensor, a first frequency voltage conversion module, a displacement sensor, a second frequency voltage conversion module, and a division operation module. The input terminal of the first voltage conversion module is connected to the power supply voltage. The output terminal of the first voltage conversion module is connected to the power supply terminal of the speed sensor, the power supply terminal of the first frequency voltage conversion module, the power supply terminal of the speed sensor, the power supply terminal of the second frequency voltage conversion module, and the power supply terminal of the division operation module. The division operation module includes a divisor signal input terminal and a dividend signal input terminal. The speed sensor is used to collect the rotational speed of the gears in the rack and pinion steering system to output a rotational frequency signal. The speed sensor is used to collect the moving speed of the gears in the rack and pinion steering system to output a moving frequency signal. The output terminal of the speed sensor is connected to the input terminal of the first frequency-voltage conversion module, and the output terminal of the first frequency-voltage conversion module is connected to the dividend signal input terminal of the division module; the output terminal of the speed sensor is connected to the input terminal of the second frequency-voltage conversion module, and the output terminal of the second frequency-voltage conversion module is connected to the divisor signal input terminal of the division module; the division module is used to output the transmission ratio signal.

[0005] The beneficial effects of this utility model are: by using two frequency-voltage conversion modules to convert the frequency signals output by the speed sensor and the displacement sensor into voltage signals respectively, and then comparing the two voltage signals, the real-time transmission ratio of the gear and rack can be obtained; this solves the technical problem in the prior art that the actual transmission ratio of the gear and rack transmission mechanism cannot be reflected, which leads to the inability to determine whether the vehicle steering system has a risk of failure.

[0006] Based on the above technical solution, the present invention can be further improved as follows.

[0007] Furthermore, the speed sensor is a Hall effect speed sensor.

[0008] Furthermore, the movement speed sensor is a Hall effect movement speed sensor.

[0009] Furthermore, the first frequency-voltage conversion module is the same as the second frequency-voltage conversion module.

[0010] The advantage of adopting the above-mentioned further solution is that by setting the two frequency-voltage conversion modules to be the same, the range of frequency-to-voltage conversion can be the same, thereby improving the calculation accuracy of the transmission ratio.

[0011] Furthermore, the first frequency voltage conversion module or the second frequency voltage conversion module includes a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, a first capacitor, a second capacitor, and a frequency voltage conversion chip; The timing circuit of the frequency-voltage conversion chip is connected to one end of the first resistor and one end of the first capacitor, respectively. The other end of the first capacitor is grounded, and the other end of the first resistor is connected to the output of the first voltage conversion module. The inverting input terminal of the comparator of the frequency-voltage conversion chip is connected to one end of the second resistor and one end of the second capacitor, respectively. The other end of the second resistor is connected to the output terminal of the first voltage conversion module, and the other end of the second capacitor is connected to the output terminal of the speed sensor or the output terminal of the motion sensor. The non-inverting input terminal of the comparator of the frequency-voltage conversion chip is connected to one end of the third resistor and one end of the fourth resistor, respectively. The other end of the third resistor is grounded, and the other end of the fourth resistor is connected to the power supply terminal of the frequency-voltage conversion chip. The power supply terminal of the frequency-voltage conversion chip is connected to the output terminal of the first voltage conversion module. The frequency output terminal and ground terminal of the frequency-voltage conversion chip are both grounded. The reference current terminal of the frequency-voltage conversion chip is connected to one end of the fifth resistor, the other end of the fifth resistor is connected to one end of the sixth resistor, and the other end of the sixth resistor is grounded. The output terminal of the frequency-voltage conversion chip is connected to one end of the seventh resistor, and the other end of the seventh resistor is grounded. The output terminal of the frequency-voltage conversion chip is connected to the dividend signal input terminal or the divisor signal input terminal of the division operation module.

[0012] Furthermore, the first frequency-voltage conversion module or the second frequency-voltage conversion module also includes a third capacitor, one end of which is connected to the output terminal of the frequency-voltage conversion chip, and the other end of which is grounded.

[0013] The beneficial effect of adopting the above-mentioned further solution is that by setting a third capacitor, noise at the output of the frequency-voltage conversion chip can be filtered out, thereby improving the stability of the output signal.

[0014] Furthermore, the frequency-voltage conversion chip is an LM331 frequency-voltage conversion chip.

[0015] Furthermore, the sixth resistor is a variable resistor.

[0016] The advantage of adopting the above-mentioned further solution is that by setting the sixth resistor as a variable resistor, the current at the reference current terminal of the frequency voltage conversion chip can be adjusted by adjusting the resistance value of the sixth resistor.

[0017] Furthermore, the division operation module is an MPY100 divider chip.

[0018] Furthermore, it also includes a second voltage conversion module, a display module, a microcontroller, and an analog-to-digital conversion module. The input terminal of the second voltage conversion module is connected to the output terminal of the first voltage conversion module, and the output terminal of the second voltage conversion module is connected to the power supply terminal of the display module, the power supply terminal of the microcontroller, and the power supply terminal of the analog-to-digital conversion module, respectively. The input terminal of the analog-to-digital conversion module is connected to the output terminal of the division operation module, and the output terminal of the analog-to-digital conversion module is connected to the signal input terminal of the microcontroller. The transceiver terminal of the microcontroller is connected to the transceiver terminal of the display module.

[0019] The beneficial effect of adopting the above-mentioned further solution is that, by setting up a display module, a microcontroller, and an analog-to-digital conversion module, the analog signal output by the division operation module can be converted into a digital signal using the analog-to-digital conversion module, and the digital signal can be transmitted to the display module for display using the microcontroller, so as to intuitively understand the real-time transmission ratio of the gear and rack. Attached Figure Description

[0020] Figure 1 This is the circuit schematic diagram of this utility model; Figure 2 The circuit diagrams are for the first frequency voltage conversion module and the second frequency voltage conversion module.

[0021] The attached diagram lists the components represented by each number as follows: 1. First voltage conversion module; 2. Speed ​​sensor; 3. Second frequency voltage conversion module; 4. Division operation module; 5. Speed ​​sensor; 6. First frequency voltage conversion module; 7. Second voltage conversion module; 8. Display module; 9. Microcontroller; 10. Analog-to-digital conversion module. Detailed Implementation

[0022] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model.

[0023] like Figure 1 As shown, this embodiment provides a transmission ratio detection device for a rack and pinion steering system, including a first voltage conversion module 1, a speed sensor 5, a first frequency voltage conversion module 6, a speed sensor 2, a second frequency voltage conversion module 3, a division operation module 4, a second voltage conversion module 7, a display module 8, a microcontroller 9, and an analog-to-digital conversion module 10; the division operation module 4 is an MPY100 divider chip; the output voltage of the division operation module 4 is 10V2 / V1.

[0024] Since the power supply voltage of vehicle steering systems is mostly 24V, the first voltage conversion module 1 is a voltage drop module that converts 24V to 12V, and the second frequency voltage conversion module 3 is a voltage drop module that converts 12V to 5V. Both the first voltage conversion module 1 and the second frequency voltage conversion module 3 can be directly obtained from the market. The speed sensor 5 is a Hall speed sensor, and the movement speed sensor 2 is a Hall movement speed sensor. The Hall speed sensor is used to detect the rotational speed of the gear to obtain a rotational frequency signal; the Hall movement speed sensor is used to detect the movement speed of the gear to obtain a movement frequency signal.

[0025] The input terminal of the first voltage conversion module 1 is connected to the power supply voltage. The output terminal of the first voltage conversion module 1 is connected to the power supply terminal of the speed sensor 5, the power supply terminal of the first frequency voltage conversion module 6, the power supply terminal of the speed sensor 2, the power supply terminal of the second frequency voltage conversion module 3, and the power supply terminal of the division operation module 4. The division operation module 4 includes a divisor signal input terminal and a dividend signal input terminal. The speed sensor 5 is used to collect the rotational speed of the gears in the rack and pinion steering system to output a rotational frequency signal. The speed sensor 2 is used to collect the moving speed of the gears in the rack and pinion steering system to output a moving frequency signal.

[0026] The output terminal of the speed sensor 5 is connected to the input terminal of the first frequency voltage conversion module 6, and the output terminal of the first frequency voltage conversion module 6 is connected to the dividend signal input terminal of the division operation module 4; the output terminal of the speed sensor 2 is connected to the input terminal of the second frequency voltage conversion module 3, and the output terminal of the second frequency voltage conversion module 3 is connected to the divisor signal input terminal of the division operation module 4; the division operation module 4 is used to output the transmission ratio signal.

[0027] The input terminal of the second voltage conversion module 7 is connected to the output terminal of the first voltage conversion module 1. The output terminal of the second voltage conversion module 7 is connected to the power supply terminal of the display module 8, the power supply terminal of the microcontroller 9, and the power supply terminal of the analog-to-digital conversion module 10, respectively. The input terminal of the analog-to-digital conversion module 10 is connected to the output terminal of the division operation module 4. The output terminal of the analog-to-digital conversion module 10 is connected to the signal input terminal of the microcontroller 9. The transceiver terminal of the microcontroller 9 is connected to the transceiver terminal of the display module 8.

[0028] The analog signal output from the division module 4 is converted into a digital signal by the analog-to-digital converter module 10, and the digital signal is transmitted to the display module 8 by the microcontroller 9 for display, so as to intuitively understand the real-time transmission ratio of the gear and rack.

[0029] This utility model embodiment utilizes two frequency-voltage conversion modules to convert the frequency signals output by the speed sensor 5 and the displacement sensor 2 into voltage signals, respectively. The two voltage signals are then compared to obtain the real-time transmission ratio of the gear and rack. This solves the technical problem in the prior art that the actual transmission ratio of the gear and rack transmission mechanism cannot be reflected, which leads to the inability to determine whether the vehicle steering system is at risk of failure.

[0030] In some embodiments, the first frequency-to-voltage conversion module 6 is the same as the second frequency-to-voltage conversion module 3. By making the two frequency-to-voltage conversion modules identical, the range of frequency-to-voltage conversion can be made the same, thereby improving the calculation accuracy of the transmission ratio.

[0031] like Figure 2 As shown, the first frequency-voltage conversion module 6 or the second frequency-voltage conversion module 3 includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a first capacitor C1, a second capacitor C2, and a frequency-voltage conversion chip U2; the sixth resistor R6 is a variable resistor. By setting the sixth resistor R6 as a variable resistor, the current at the reference current terminal of the frequency-voltage conversion chip U2 can be adjusted by adjusting the resistance value of the sixth resistor R6.

[0032] The timing circuit of the frequency-voltage conversion chip U2 is connected to one end of the first resistor R1 and one end of the first capacitor C1, respectively. The other end of the first capacitor C1 is grounded, and the other end of the first resistor R1 is connected to the output of the first voltage conversion module 1. The inverting input terminal of the comparator of the frequency-voltage conversion chip U2 is connected to one end of the second resistor R2 and one end of the second capacitor C2, respectively. The other end of the second resistor R2 is connected to the output terminal of the first voltage conversion module 1, and the other end of the second capacitor C2 is connected to the output terminal of the speed sensor 5 or the output terminal of the speed sensor 2. The non-inverting input terminal of the comparator of the frequency-voltage conversion chip U2 is connected to one end of the third resistor R3 and one end of the fourth resistor R4, respectively. The other end of the third resistor R3 is grounded, and the other end of the fourth resistor R4 is connected to the power supply terminal of the frequency-voltage conversion chip U2. The power supply terminal of the frequency-voltage conversion chip U2 is connected to the output terminal of the first voltage conversion module 1. The frequency output terminal and ground terminal of the frequency-voltage conversion chip U2 are both grounded. The reference current terminal of the frequency-voltage conversion chip U2 is connected to one end of the fifth resistor R5. The other end of the fifth resistor R5 is connected to one end of the sixth resistor R6. The other end of the sixth resistor R6 is grounded. The output terminal of the frequency-voltage conversion chip U2 is connected to one end of the seventh resistor R7, and the other end of the seventh resistor R7 is grounded. The output terminal of the frequency-voltage conversion chip U2 is connected to the dividend signal input terminal or the divisor signal input terminal of the division operation module 4.

[0033] like Figure 2 As shown, when the falling edge of the pulse signal arrives, a negative spike pulse appears at pin 6. When the voltage at pin 6 is lower than that at pin 7, the input comparator outputs a high level, the RS flip-flop is set, the Q terminal outputs a high level, the current switch connects to pin 1, and the mirrored current source charges capacitor C3, causing pin 1 to output a high level. At this time, because the reset transistor is off, the power supply VCC charges capacitor C1 through resistor R1. When the voltage across C1 is greater than 2 / 3 VCC, the timing comparator outputs a high level, the RS flip-flop is reset (at this time, the voltage at pin 6 is already higher than that at pin 7), the Q terminal outputs a low level, the current switch disconnects from pin 1, and C3 discharges through R7, maintaining the voltage at pin 1. Simultaneously, the reset transistor turns on, and C1 discharges. When the falling edge of the next pulse signal arrives, the above process is repeated, thus realizing the conversion between frequency and voltage.

[0034] The voltage at pin 1 is Vo = I × R7, where I is the average current flowing through pin 1, and its magnitude is I = i × (1.1R1C1) × fIN. Where i = 1.90V / R6 + R7. From the above, we can deduce: Wherein, V1 represents the output voltage of the second frequency voltage conversion module, V2 represents the output voltage of the first frequency voltage conversion module, and fIN represents the output voltage of the second frequency voltage conversion module or the frequency signal at the input terminal of the first frequency voltage conversion module.

[0035] In some embodiments, the first frequency-voltage conversion module 6 or the second frequency-voltage conversion module 3 further includes a third capacitor C3, one end of which is connected to the output terminal of the frequency-voltage conversion chip U2, and the other end of which is grounded.

[0036] By adding a third capacitor C3, noise at the output of the frequency-to-voltage converter chip U2 can be filtered out, thereby improving the stability of the output signal. Furthermore, the frequency-to-voltage converter chip U2 is an LM331 frequency-to-voltage converter chip.

[0037] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the concept and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A transmission ratio detection device for a rack and pinion steering system, characterized in that: It includes a first voltage conversion module (1), a speed sensor (5), a first frequency voltage conversion module (6), a speed sensor (2), a second frequency voltage conversion module (3), and a division operation module (4); The input terminal of the first voltage conversion module (1) is connected to the power supply voltage. The output terminal of the first voltage conversion module (1) is connected to the power supply terminal of the speed sensor (5), the power supply terminal of the first frequency voltage conversion module (6), the power supply terminal of the speed sensor (2), the power supply terminal of the second frequency voltage conversion module (3), and the power supply terminal of the division operation module (4). The division operation module (4) includes a divisor signal input terminal and a dividend signal input terminal. The speed sensor (5) is used to collect the rotational speed of the gears in the rack and pinion steering system to output a rotational frequency signal. The speed sensor (2) is used to collect the moving speed of the gears in the rack and pinion steering system to output a moving frequency signal. The output terminal of the speed sensor (5) is connected to the input terminal of the first frequency voltage conversion module (6), and the output terminal of the first frequency voltage conversion module (6) is connected to the dividend signal input terminal of the division operation module (4); the output terminal of the speed sensor (2) is connected to the input terminal of the second frequency voltage conversion module (3), and the output terminal of the second frequency voltage conversion module (3) is connected to the divisor signal input terminal of the division operation module (4); the division operation module (4) is used to output the transmission ratio signal.

2. The gear and rack steering system transmission ratio detection device according to claim 1, characterized in that: The speed sensor (5) is a Hall speed sensor.

3. The gear and rack steering system transmission ratio detection device according to claim 1, characterized in that: The speed sensor (2) is a Hall speed sensor.

4. The gear and rack steering system transmission ratio detection device according to claim 1, characterized in that: The first frequency voltage conversion module (6) is the same as the second frequency voltage conversion module (3).

5. The gear and rack steering system transmission ratio detection device according to claim 4, characterized in that: The first frequency voltage conversion module (6) or the second frequency voltage conversion module (3) includes a first resistor (R1), a second resistor (R2), a third resistor (R3), a fourth resistor (R4), a fifth resistor (R5), a sixth resistor (R6), a seventh resistor (R7), a first capacitor (C1), a second capacitor (C2), and a frequency voltage conversion chip (U2). The timing circuit of the frequency-voltage conversion chip (U2) is connected to one end of the first resistor (R1) and one end of the first capacitor (C1), respectively. The other end of the first capacitor (C1) is grounded, and the other end of the first resistor (R1) is connected to the output terminal of the first voltage conversion module (1). The inverting input terminal of the comparator of the frequency-voltage conversion chip (U2) is connected to one end of the second resistor (R2) and one end of the second capacitor (C2), respectively. The other end of the second resistor (R2) is connected to the output terminal of the first voltage conversion module (1), and the other end of the second capacitor (C2) is connected to the output terminal of the speed sensor (5) or the output terminal of the speed sensor (2). The non-inverting input terminal of the comparator of the frequency-voltage conversion chip (U2) is connected to one end of the third resistor (R3) and one end of the fourth resistor (R4), respectively. The other end of the third resistor (R3) is grounded, and the other end of the fourth resistor (R4) is connected to the power supply terminal of the frequency-voltage conversion chip (U2). The power supply terminal of the frequency-voltage conversion chip (U2) is connected to the output terminal of the first voltage conversion module (1). The frequency output terminal and ground terminal of the frequency-voltage conversion chip (U2) are both grounded. The reference current terminal of the frequency-voltage conversion chip (U2) is connected to one end of the fifth resistor (R5), the other end of the fifth resistor (R5) is connected to one end of the sixth resistor (R6), and the other end of the sixth resistor (R6) is grounded. The output terminal of the frequency-voltage conversion chip (U2) is connected to one end of the seventh resistor (R7), and the other end of the seventh resistor (R7) is grounded. The output terminal of the frequency-voltage conversion chip (U2) is connected to the dividend signal input terminal of the division operation module (4) or the divisor signal input terminal of the division operation module (4).

6. The gear and rack steering system transmission ratio detection device according to claim 5, characterized in that: The first frequency voltage conversion module (6) or the second frequency voltage conversion module (3) further includes a third capacitor (C3), one end of which is connected to the output terminal of the frequency voltage conversion chip (U2), and the other end of which is grounded.

7. The gear and rack steering system transmission ratio detection device according to claim 5, characterized in that: The frequency-voltage conversion chip (U2) is an LM331 frequency-voltage conversion chip.

8. The gear and rack steering system transmission ratio detection device according to claim 5, characterized in that: The sixth resistor (R6) is a variable resistor.

9. The gear and rack steering system transmission ratio detection device according to claim 1, characterized in that: The division operation module (4) is an MPY100 divider chip.

10. The gear and rack steering system transmission ratio detection device according to claim 1, characterized in that: It also includes a second voltage conversion module (7), a display module (8), a microcontroller (9), and an analog-to-digital conversion module (10). The input terminal of the second voltage conversion module (7) is connected to the output terminal of the first voltage conversion module (1). The output terminal of the second voltage conversion module (7) is connected to the power supply terminal of the display module (8), the power supply terminal of the microcontroller (9), and the power supply terminal of the analog-to-digital conversion module (10). The input terminal of the analog-to-digital conversion module (10) is connected to the output terminal of the division operation module (4). The output terminal of the analog-to-digital conversion module (10) is connected to the signal input terminal of the microcontroller (9). The transceiver terminal of the microcontroller (9) is connected to the transceiver terminal of the display module (8).

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