Control device and control system capable of communicating with proximity switch

Abstract

The invention provides a control device and a control system capable of communicating with a proximity switch, the control device is used for performing bidirectional communication with the proximity switch, and the control device converts MTX data of an MCU module into CTX data of the control device through a first pulse reverse module, a voltage regulation circuit module, a follower circuit module and a push-pull circuit module. The data is sent to the proximity switch, so that the control device transmits data to the proximity switch; the control device receives output data of the proximity switch and converts the output data into CRX data, the CRX data is converted into MRX data of the MCU module after passing through the comparator, the first level conversion module and the second pulse reverse module, and the purpose that the proximity switch transmits data to the control device is achieved. According to the invention, by using the existing proximity switch cable, bidirectional communication between the control device and the proximity switch is realized, and distance calibration, temperature calibration and online program upgrading of the proximity switch are facilitated.

Description

Technical Field

[0001] The present invention relates to the field of sensor communication technology, and in particular to a control device and a control system capable of communicating with a proximity switch. Background Art

[0002] With the development of industrial automation, the working conditions of discrete proximity switches are becoming more and more complex, requiring high protection performance and compact appearance design, without extra space to add cables for data transmission. Commonly used connection lines for proximity switches include positive power supply, negative power supply, and output line. The working voltage is generally 10-30V DC, which is much higher than the TTL level and cannot be used for direct communication.

[0003] However, when producing proximity switches, distance calibration, temperature coefficient calibration and other processes are performed, data transmission is required, and communication function is required. Existing proximity switches usually do not have communication function, so it is necessary to provide a control device that can communicate with the proximity switch. Summary of the invention

[0004] In view of the defects in the prior art, the purpose of the present invention is to provide a control device and a control system that can communicate with a proximity switch. The present invention utilizes the existing proximity switch cable to achieve two-way communication between the control device and the proximity switch, thereby facilitating distance calibration, temperature calibration and online program upgrade of the proximity switch.

[0005] To solve the above problems, the technical solution of the present invention is:

[0006] A control device capable of communicating with a proximity switch, the control device being used for bidirectional communication with the proximity switch, the control device converting M_TX data of an MCU module into C_TX data of the control device via a first pulse inversion module, a voltage regulating circuit module, a following circuit module, and a push-pull circuit module, and then sending the data to the proximity switch, thereby realizing data transmission from the control device to the proximity switch; the control device receives output data of the proximity switch, and converts the output data into C_RX data, which is converted into M_RX data of the MCU module via a comparator, a first level conversion module, and a second pulse inversion module, thereby realizing data transmission from the proximity switch to the control device.

[0007] Preferably, the MCU module of the control device is used to send the M_TX data to the first pulse reversal module, and control whether the M_TX data is reversed through EN1 of the first pulse reversal module.

[0008] Preferably, the proximity switch is provided with a level conversion module for converting C_TX data into TTL level.

[0009] Preferably, the voltage of C_RX is divided by resistors R1 and R2 and compared with the reference voltage. When the voltage is greater than the reference voltage, the comparator outputs a high level, and when the voltage is less than the reference voltage, the comparator outputs a low level.

[0010] Preferably, the first level conversion module converts the output voltage of the comparator into a TTL level, and controls whether the M_RX data is reversed through EN2 of the second pulse inversion module.

[0011] A control system comprises a proximity switch and a control device communicating with the proximity switch. The control device and the proximity switch together convert the level of serial port data twice to realize data transmission and reception. The positive power pole of the proximity switch is not only used for power supply but also for communication reception. The output of the proximity switch is not only used for outputting switch quantity signals but also for communication transmission, that is, the control device can receive data from the proximity switch and the proximity switch can receive instructions from the control device, thereby realizing two-way communication between the proximity switch and the control device.

[0012] Preferably, the output of the proximity switch includes an NPN type and a PNP type.

[0013] Preferably, a level conversion module is provided in the proximity switch.

[0014] Compared with the prior art, the present invention utilizes the wider working voltage of the proximity switch and performs level changes within this voltage range, thereby realizing data transmission while the proximity switch is powered normally. The existing proximity switch cable is utilized to realize two-way communication between the control device and the proximity switch, thereby facilitating distance calibration, temperature calibration, and online program upgrades of the proximity switch. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0016] Figure 1 It is the structure diagram of the control system of the present invention;

[0017] Figure 2 It is a positive pulse diagram;

[0018] Figure 3 This is a reverse pulse diagram. DETAILED DESCRIPTION

[0019] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0020] Specifically, the present invention provides a control device and a control system that can communicate with a proximity switch, such as Figure 1 As shown, the control system includes a proximity switch and a control device that can communicate with the proximity switch. The control device and the proximity switch together convert the level of the serial port data twice to realize the sending and receiving of data. The positive pole of the power supply of the proximity switch is not only used for power supply, but also for communication reception. The output of the proximity switch is not only used for outputting switch quantity signals, but also for communication transmission. That is, the control device can receive data from the proximity switch, and the proximity switch can receive instructions from the control device, thereby realizing two-way communication between the proximity switch and the control device. The present invention utilizes the wide working voltage of the proximity switch, and performs level changes within this voltage range to realize normal power supply of the proximity switch while realizing data transmission.

[0021] Specifically, the control device converts the M_TX data of the MCU module into C_TX data through the first pulse reversing module, the voltage regulating circuit module, the following circuit module, and the push-pull circuit module. Then, the C_TX is converted into the TTL level through the level conversion module inside the proximity switch, so that the control device transmits data to the proximity switch. In order to match the TX conversion of the proximity switch output, whether the load 1 and load 2 in the control device are opened and closed, through the U2 comparator, the first level conversion module, and the second pulse reversing module, the proximity switch transmits data to the control device.

[0022] The USB in the control device can be connected to a computer for human-computer interaction. The MCU module is used to send the M_TX data to the first pulse reverse module, and control whether the M_TX data is reversed through EN1. The voltage regulating circuit module is used to convert the TTL level of the first pulse reverse module into high and low level changes of V0 and V1 or high and low level changes of V3 and V4, and change it into C_TX signal after passing through the follower circuit module and the push-pull circuit module. The C_TX signal has positive pulse changes and negative pulse changes. Whether the pulse is flipped is controlled by EN1 of the first pulse direction module. The push-pull circuit module improves the load capacity and also ensures that the pulse change slope is steep. The pulse voltage value is between Vbmin and Vbmax. Generally, the minimum operating voltage Vbmin of the proximity switch is usually 10V, and the maximum limit voltage Vbmax is usually 30V. Since V0 and V3 are greater than Vbmin, the proximity switch ensures normal power supply during the communication process; V1 and V4 are less than Vbmax, and the proximity switch will not be damaged. When the control device sends data to the proximity switch, the pulse voltage change from the MCU module M_TX to C_TX in the control device is transmitted to the proximity switch, and then after passing through the level conversion module in the proximity switch, the voltage changes of V0 and V1, V3 and V4 are converted into the high and low level changes of TTL, that is, the TTL level is converted to the C_TX level. Among them, the low level of C_TX and C_RX is V0 or V3, and the high level of C_TX and C_RX is V1 or V4. Figure 2 The positive pulse and Figure 3 The reverse pulse is shown.

[0023] When the output of the proximity switch is NPN type, the MCU module EN3 in the control device is 1, EN4 is 0, load 1 is closed, and load 2 is open. Connect load 1 to the output of the proximity switch to achieve the TX level conversion of the proximity switch output to C_RX. When the output of the proximity switch is PNP type, the MCU module EN3 in the control device is 0, EN4 is 1, load 1 is open, and load 2 is closed. Connect load 2 to the output of the proximity switch to achieve the TX level conversion of the proximity switch output to C_RX.

[0024] When the voltage of C_RX is divided by resistors R1 and R2, it is compared with the reference voltage. When it is greater than the reference voltage, the U2 comparator outputs a high level, and when it is less than the reference voltage, the U2 comparator outputs a low level. The first level conversion module converts the output voltage of the U2 comparator into a TTL level. The second pulse inversion module is controlled by EN2 to reverse the M_RX data according to the configuration, thereby improving the flexibility of use.

[0025] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A control device capable of communicating with a proximity switch, characterized in that: The control device is used for bidirectional communication with the proximity switch. The control device converts the M_TX data of the MCU module into C_TX data of the control device through the first pulse reversal module, the voltage regulation circuit module, the follower circuit module, and the push-pull circuit module, and then sends it to the proximity switch, so that the control device transmits data to the proximity switch; the control device receives the output data of the proximity switch, and converts the output data into C_RX data, which is converted into M_RX data of the MCU module after passing through the comparator, the first level conversion module, and the second pulse reversal module, so that the proximity switch transmits data to the control device.

2. The control device capable of communicating with a proximity switch according to claim 1, characterized in that: The MCU module of the control device is used to send the M_TX data to the first pulse reversal module, and control whether the M_TX data is reversed through EN1 of the first pulse reversal module.

3. The control device capable of communicating with a proximity switch according to claim 1, characterized in that: The proximity switch is provided with a level conversion module for converting C_TX data into TTL level.

4. The control device capable of communicating with a proximity switch according to claim 1, characterized in that: The voltage of C_RX is divided by resistors R1 and R2 and compared with the reference voltage. When it is greater than the reference voltage, the comparator outputs a high level, and when it is less than the reference voltage, the comparator outputs a low level.

5. The control device capable of communicating with a proximity switch according to claim 4, characterized in that: The first level conversion module converts the output voltage of the comparator into a TTL level, and controls whether the M_RX data is reversed through EN2 of the second pulse inversion module.

6. A control system, characterized in that: The control system includes a proximity switch and a control device as described in any one of claims 1 to 5. The control device and the proximity switch together convert the level of the serial port data twice to realize data sending and receiving. The positive power pole of the proximity switch is not only used for power supply, but also for communication reception; the output of the proximity switch is not only used for outputting switch signals, but also for communication transmission, that is, the control device can receive data from the proximity switch, and the proximity switch can receive instructions from the control device, thereby realizing two-way communication between the proximity switch and the control device.

7. The control system according to claim 6, characterized in that: The output of the proximity switch includes NPN type and PNP type.

8. The control system according to claim 6, characterized in that: A level conversion module is provided in the proximity switch.

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