Control device based on resistance value conversion

Abstract

The utility model relates to a control device based on resistance value conversion, which belongs to the technical field of instrument resistance conversion and comprises an upper computer 485 interface unit, a control unit, a transmission unit, a motor driving unit and a stepping motor. The output end of the control unit is connected with the input end of the motor driving unit through the transmission unit; the utility model has the beneficial effects that the size is small, the performance index is high, the host computer 485 interface unit is adopted to receive the resistance value data displayed by the instrument, the control unit CU drives the motor and the potentiometer to rotate synchronously, and the resistance value conversion is completed, so that the occupied space of the system is small, a resistance network and a change-over switch with complex and tedious lines are omitted, and the cost is reduced. The stability of the system is improved; the resistance value can be continuously adjusted in the whole interval without interruption points, so that the display of the instrument is free from a jitter phenomenon, and the sensitivity and accuracy are effectively improved.

Description

Technical Field

[0001] This utility model relates to a control device based on resistance value transformation, belonging to the field of instrument resistance transformation technology. Background Technology

[0002] Aviation instrument display data requires external sensors to provide passive low-impedance signals of 90~130Ω and 47~220Ω. The traditional solution is to use digital potentiometers. The digital potentiometer chip integrates 256 resistor networks to convert the signals from the host computer and then switches between different taps to achieve different resistance values. The lowest range of a conventional digital potentiometer is 1K, which cannot meet the instrument display requirements. However, although controlling aviation instruments through discrete component resistor networks can meet the requirements, it has the problems of complex circuits, low accuracy, and jumps in resistance value output. Utility Model Content

[0003] To address the problems of complex circuits, low precision, and jumps in resistance output, this invention proposes a control device based on resistance value transformation.

[0004] The technical solution adopted by this utility model to solve the above problems is as follows:

[0005] This utility model discloses a control device based on resistance value transformation, which includes a host computer 485 interface unit, a control unit, a transmission unit, a motor drive unit, and a stepper motor. The output terminal of the host computer 485 interface unit is connected to the input terminal of the control unit. The output terminal of the control unit is connected to the input terminal of the motor drive unit through the transmission unit. The motor drive unit is connected to the stepper motor through a circuit, and the motor drive unit controls the stepper motor.

[0006] Furthermore, the device also includes a power supply. The host computer 485 interface unit, the control unit, and the motor drive unit are all powered by the power supply. The power supply voltage for the host computer 485 interface unit and the control unit is 5V, and the power supply voltage for the motor drive unit is 24V.

[0007] Furthermore, the stepper motor output shaft is flexibly connected to a potentiometer via a coupling, and the pins of the potentiometer are fixedly connected to the connection terminals of the aviation instruments.

[0008] Furthermore, a light-emitting element is fixedly connected to the output terminal of the control unit.

[0009] Furthermore, a differential bus receiver is provided between the host computer 485 interface unit and the control unit.

[0010] Furthermore, the device also includes limit switches and Hall switches, both of which are connected in parallel to the control unit. The limit switches are used to adjust the extreme positions of the motor rotation, and the Hall switches are used to adjust the motor's return-to-origin position.

[0011] The beneficial effects of this utility model are:

[0012] 1. This utility model has small size and high performance. It uses a host computer 485 interface unit to receive the resistance value data displayed by the instrument. The control unit CU drives the motor and potentiometer to rotate synchronously to complete the resistance value change. This makes the system occupy less space, eliminates the complex and cumbersome resistor network and switching switch, and improves the stability of the system.

[0013] 2. The signal from the host computer is received by the RS485-A and RS485-B receivers via shielded twisted-pair cable through the host computer's 485 interface unit. It is converted to TTL level and then received by the control unit. The signal is converted again in the control unit and transmitted to the photoelectric converter of the motor drive unit, where it is converted into a DC voltage signal. This signal is processed by the motor drive unit's program and amplified, giving the motor drive unit sufficient driving capability to drive the motor and potentiometer. This allows for continuous adjustment of the resistance value throughout the entire range without interruptions, resulting in a jitter-free instrument display and effectively improving sensitivity and accuracy. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the principle of this utility model;

[0015] Figure 2 This is the electrical schematic diagram of this utility model.

[0016] In the diagram: 1. Host computer; 2. Differential bus receiver; 4. Control unit; 5. Limit switch; 6. Hall switch; 7. Transmission unit; 8. Motor drive unit; 9. Stepper motor; 10. Power supply; 11. Potentiometer; 2. Flexible coupling; 13. Aviation instrument. Detailed Implementation

[0017] Specific implementation method one: as follows Figures 1 to 2 As shown, this embodiment of a control device based on resistance value transformation includes a host computer 485 interface unit 1, a control unit 4, a transmission unit 7, a motor drive unit 8, and a stepper motor 9. The output terminal of the host computer 485 interface unit 1 is connected to the input terminal of the control unit 4. The output terminal of the control unit 4 is connected to the input terminal of the motor drive unit 8 through the transmission unit 7. The motor drive unit 8 and the stepper motor 9 are connected by a line. The motor drive unit 8 controls the stepper motor 9. The control unit 4 is a microcontroller. The motor drive unit 8 is equipped with a photoelectric converter.

[0018] The host computer sends a resistance signal, which is received by the host computer's RS485-A and RS485-B receivers via shielded twisted-pair cable. The signal is converted to TTL level and then received by the control unit 4. The signal is converted in the control unit 4 and transmitted to the photoelectric converter of the motor drive unit 8 via the transmission unit 7. The converter converts the signal into a DC voltage signal. This signal is processed by the motor drive unit 8 and amplified to give the motor drive unit 8 sufficient driving capability to drive the motor and potentiometer to rotate, thus completing the resistance conversion.

[0019] After the signal is converted in control unit 4, it is compared with the previously received original data by the chip's internal program. Transmission unit 7 transmits multiple signals. If they are equal, the motor does not move. If they are greater, a difference calculation is performed, and the result is converted into motor rotation angle data. A low-level signal, GX_DIR=0, is output through port RC3 of control unit 4. This signal is then converted by motor drive unit 8 to control stepper motor 9 to rotate forward. At the same time, port RC4 of control unit 4 outputs the number of pulses required for the rotation angle of stepper motor 9, driving GX_Clock to flip. This is then converted by motor drive unit 8 to control stepper motor 9 to rotate under pulse train drive. Each pulse output decrements the pulse output counter until it reaches zero, at which point the pulse output stops, and stepper motor 9 stops. Conversely, if the difference calculation result is negative, port RC3 of control unit 4 outputs a high-level signal, GX_DIR=1, and motor drive unit 8 converts the signal to reverse stepper motor 9.

[0020] Specific implementation method two: such as Figures 1 to 2 As shown, in this embodiment, the device also includes a power supply 10. The host computer 485 interface unit 1, the control unit 4, and the motor drive unit 8 are all powered by the power supply 10. The power supply voltage between the power supply 10 and the host computer 485 interface unit 1 and the control unit 4 is 5V, and the power supply voltage between the power supply 10 and the motor drive unit 8 is 24V. The power supply 10 provides power to the host computer 485 interface unit 1, the control unit 4, and the motor drive unit 8 of the device, providing the prerequisites for the operation of the nuclear device. The power supply voltage between the power supply 10 and the host computer 485 interface unit 1 and the control unit 4 is 5V, and the power supply voltage between the power supply 10 and the motor drive unit 8 is 24V, which can effectively ensure current stability.

[0021] Specific implementation method three: such as Figures 1 to 2 As shown, in this embodiment, the output shaft of the stepper motor 9 is flexibly connected to the potentiometer 11 via a flexible coupling 2. The pins of the potentiometer 11 are fixedly connected to the connection terminals of the aviation instrument 13. The flexible coupling 2 enables the output shaft of the stepper motor 9 to be flexibly connected to the potentiometer 11, thereby utilizing the elastic deformation of the elastic element to compensate for the relative displacement, mitigate impact and absorb vibration, and effectively protect the stepper motor 9 and the potentiometer 11.

[0022] Specific implementation method four: such as Figures 1 to 2 As shown, the output terminal of the control unit 4 in this embodiment is fixedly connected to a light-emitting device. When the control unit 4 receives the signal converted and transmitted by the host computer 485 interface unit, the signal is converted in the control unit 4, and the output terminal of the control unit 4 drives the light-emitting device to react, thereby reflecting the signal reception status.

[0023] Specific implementation method five: such as Figures 1 to 2 As shown, in this embodiment, a differential bus receiver 2 is provided between the host computer 485 interface unit 1 and the control unit 4. The differential bus receiver is powered by an isolated design, with independent +5V input and output, and signal magnetic isolation technology, which makes the signal transmission stable and reliable. The resistance value is continuously adjustable throughout the entire range without any discontinuity.

[0024] Specific implementation method six: such as Figures 1 to 2 As shown, in this embodiment, the device also includes a limit switch 5 and a Hall switch 6. Both the limit switch 5 and the Hall switch 6 are connected in parallel on the control unit 4. The limit switch 5 is used to adjust the extreme position of the motor rotation, and the Hall switch 6 is used to adjust the motor's return position.

[0025] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model's technical solution. Any simple modifications, equivalent substitutions, and improvements made to the above embodiments without departing from the scope of the present utility model's technical solution, based on the technical essence of the present utility model and within the spirit and principles of the present utility model, shall still fall within the protection scope of the present utility model's technical solution.

Claims

1. A control device based on resistance value transformation, characterized in that: It includes a host computer 485 interface unit (1), a control unit (4), a transmission unit (7), a motor drive unit (8), and a stepper motor (9). The output of the host computer 485 interface unit (1) is connected to the input of the control unit (4). The output of the control unit (4) is connected to the input of the motor drive unit (8) through the transmission unit (7). The motor drive unit (8) is connected to the stepper motor (9) through a line. The motor drive unit (8) controls the stepper motor (9).

2. The control device based on resistance value transformation according to claim 1, characterized in that: It also includes a power supply (10). The host computer 485 interface unit (1), control unit (4) and motor drive unit (8) are all powered by the power supply (10). The power supply voltage of the power supply (10) to the host computer 485 interface unit (1) and control unit (4) is 5V, and the power supply voltage of the power supply (10) to the motor drive unit (8) is 24V.

3. The control device based on resistance value transformation according to claim 2, characterized in that: The output shaft of the stepper motor (9) is flexibly connected to the potentiometer (11) via a flexible coupling (12), and the pins of the potentiometer (11) are fixedly connected to the connection end of the aviation instrument (13).

4. The control device based on resistance value transformation according to claim 1, characterized in that: The output end of the control unit (4) is fixedly connected to a light-emitting element.

5. A control device based on resistance value transformation according to claim 1, characterized in that: A differential bus receiver (2) is provided between the host computer 485 interface unit (1) and the control unit (4).

6. The control device based on resistance value transformation according to claim 5, characterized in that: It also includes limit switches (5) and Hall switches (6). Both limit switches (5) and Hall switches (6) are connected in parallel on the control unit (4). Limit switches (5) are used to adjust the extreme position of the motor rotation, and Hall switches (6) are used to adjust the position of the motor returning to the origin.

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