Universal-interface programmable controller

Abstract

A universal interface programmable controller comprises a CPU (central processing unit) board and 16 groups of IO (input / output) boards, current sensor signals of a power circuit are also accessed to the CPU board, the CPU board is arranged in the middle of a welding workshop, the IO boards are dispersedly arranged in grouped welding machine areas, the input end of the CPU board is connected with the 16 groups of IO boards through network cable interfaces, each group of network cable interfaces is provided with four pairs of differential signal lines, and the differential signal lines are connected with the CPU board. The four groups of differential signals are respectively a differential input interface, a differential output interface, a differential clock signal and a differential latch signal, the output board decodes and encodes the four groups of differential signals from the output end of the CPU board and then is connected with the 32 welding machines, and the monitoring computer is connected with the CPU board through a 485 bus. The whole controller controls 16 groups, each group comprises 32 welding machines, and 512 electric welding machines can be controlled in total; the CPU uses a mode similar to an SPI (Serial Peripheral Interface) bus to operate an input port and an output port, the data of 512 welding machines scanned by the programmable logic controller is less than 1mS and can reach 0.5 mS, the programmable logic controller is superior to any existing PLC in the world, and the time delay performance is superior to the 5G network standard.

Description

Technical Field

[0001] The present invention relates to a programming controller, specifically a general interface programmable controller. Background Art

[0002] In the field of equipment group control, the common practice is to connect all devices using a network. For example, in a welding machine group control system, in a situation with fewer devices, a conventional serial port connection can be used. In an intelligent manufacturing workshop for body spot welding, there are often hundreds of spot welding machines forming a spot welding machine group. If many welding machines in the group are powered on simultaneously, it will cause an excessive peak current. By adopting an intelligent on-demand queue method to connect the spot welding machines in an orderly manner, the current peak can be effectively suppressed. In a situation with a large amount of data and many devices, Ethernet communication can be used, such as Siemens PROFIBUS, ETHERNET network; Rockwell EtherNet / IP industrial Ethernet, etc. However, these communications all have different degrees of time delay. Even when using the remote IO port technology with Siemens 1200 / 1500 series programmable controllers, there will still be an uncertain time delay phenomenon, which cannot meet the actual control requirements for the cycle accuracy of welding machines. Moreover, the input and output points of the above programmable controllers are limited, and it is impossible to complete the control of hundreds of devices by one main controller. If all the main control devices of the spot welding machines are transformed into controllers meeting the high-speed Ethernet standard and then equipped with a low-delay server, the control requirements can be barely met, but it is not feasible to transform all the spot welding machines. Summary of the Invention

[0003] In order to solve the above problems, the purpose of the present invention is to provide a general interface programmable controller.

[0004] To achieve the above purpose, the technical solution of the present invention is: a general interface programmable controller, which consists of 1 CPU board and 16 groups of IO boards. The current sensor signal of the power circuit is also connected to the CPU board. The CPU board is arranged in the middle part of the welding workshop, and the IO boards are dispersedly arranged in the grouped welding machine areas. The input end of the CPU board is connected to 16 groups of IO through network cable interfaces. Each group of network cable interfaces has 4 pairs of differential signal lines, namely differential input interfaces, differential output interfaces, differential clock signals, and differential latch signals. It also includes an output board, which decodes and encodes 4 groups of differential signals from the output end of the CPU board and then connects 32 welding machines. The monitoring computer is connected to the CPU board using a 485 bus.

[0005] Further, the differential signal lines use twisted pair signal lines with a characteristic impedance of 50 ohms, and the line drive circuit uses 25LS32 or 26LV32.

[0006] Further, the main control CPU of the CPU board uses an ARM architecture processor.

[0007] Further, two isolated normally open contact signal lines are independently led out from each output port.

[0008] Further, the CPU board circuit includes a CPU with an ARM core and a chip 2003A. The output pins of the CPU are connected to the corresponding input pins of chips U17 and 2003A.

[0009] Further, the IO board circuit includes a chip RJ45A8, two chips AM26LS32, and six chips AM26LS31. The six chips AM26LS31 are respectively connected to the corresponding pins of the chip RJ45A8, and the two chips AM26LS32 are connected by a plurality of resistors.

[0010] Further, the output board includes one chip AM26LS31 and one chip AM26LS32. Four of the eight chips HC165 are connected in series and then connected to the chip AM26LS31, and the other four chips HC165 are respectively connected to the chip AM26LS32. The chip 2003A is respectively provided for connection. The 7th pins of the four chips HC165 connected to the chip AM26LS32 are also respectively connected to another chip 2003A, and the 13th pins are also respectively connected to the 3rd pin of the same clock chip 555.

[0011] With the above settings, the present invention provides a general interface programmable controller equipped with 1024 input and output points, divided into 16 groups, with each group containing 64 I / O points. Among them, there are 16 groups of differential remote IO interfaces, and each group of interfaces has 4 differential signal lines, namely: 1 input port differential signal line, 1 output port differential signal line, 1 clock differential signal line, and 1 latch differential signal circuit; the 64 I / Os of each group include 32 inputs (I) and 32 outputs (O). Each group can control 32 spot welders, and the entire controller manages 16 groups with 32 welders in each group, totaling 512 welders that can be controlled; the CPU uses a method similar to the SPI bus for input and output port operations. The programmable controller scans the data of 512 welders in less than 1 mS, reaching 0.5 mS, which is better than any existing PLC worldwide, and the latency performance is better than the 5G network standard. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The present invention will be further described in conjunction with the accompanying drawings.

[0013] Figure 1 It is the circuit diagram of the CPU board of the present invention;

[0014] Figure 2 It is the circuit diagram of the IO board of the present invention;

[0015] Figure 3 It is the circuit diagram of the output board of the present invention. Detailed implementation mode

[0016] As Figures 1-3 shown, a general interface programmable controller includes a CPU board and 16 groups of IO boards. The current sensor signal of the power circuit is also connected to the CPU board. The CPU board is arranged in the middle of the welding workshop, and the IO boards are scattered in the grouped welding machine areas. The input end of the CPU board is connected to 16 groups of IO through network cable interfaces. Each network cable interface has 4 pairs of differential signal lines, namely differential input interface, differential output interface, differential clock signal and differential latch signal. It also includes an output board. The output board decodes and encodes 4 groups of differential signals from the output end of the CPU board and connects 32 welding machines. The monitoring computer is connected to the CPU board using the 485 bus.

[0017] The differential signal lines use twisted pair signal lines with a characteristic impedance of 50 ohms. The line driver circuit uses 25LS32 or 26LV32. The main control CPU of the CPU board uses an ARM architecture processor, which has very low power consumption, reduces the heat generation of the main control, and improves the reliability of the programmable controller; 2 isolated normally open contact signal lines are independently led out from each output port to avoid the problem of ground potential difference between different welding machines.

[0018] The CPU board circuit includes a CPU with an ARM core and a chip 2003A. The output pins of the CPU are connected to the corresponding input pins of chips U17 and 2003A.

[0019] The IO board circuit includes a chip RJ45A8, 2 chips AM26LS32, and 6 chips AM26LS31. The 6 chips AM26LS31 are respectively connected to the corresponding pins of the chip RJ45A8, and the 2 chips AM26LS32 are connected through multiple resistors.

[0020] The output board includes 1 chip AM26LS31 and 1 chip AM26LS32. 4 of the 8 chips HC165 are connected in series and then connected to the chip AM26LS31. The other 4 chips HC165 are respectively connected to the chip AM26LS32, and the connected chips 2003A are respectively set. The 7th pin of the 4 chips HC165 connected to the chip AM26LS32 is also respectively connected to another chip 2003A, and the 13th pin is also respectively connected to the 3rd pin of the same clock chip 555.

[0021] In addition, DMA channels can be used for port data reading and writing, reducing the CPU time occupied by reading and writing input / output ports and optimizing performance. The programmable controller is equipped with 12 channels of 4-20mA analog input, which can collect the three-phase currents of up to 4 different power transformers, suitable for the occasion where multiple power transformers are arranged in each workshop. The programmable controller is equipped with 3 channels of 485 interfaces, which can be connected to an industrial human-machine interface to monitor various working states and can be connected to a remote controller to change control parameters at any time. The programmable controller is equipped with 1 channel of CAN interface to access the CAN network and expand CAN bus sensors. The programmable controller is equipped with an Ethernet interface for accessing the Internet or an MQTT message server and can be incorporated into the Internet of Things system or MAS system.

[0022] Working principle of the present invention:

[0023] To minimize latency as much as possible, the circuit uses 16 parallel serial input ports and 16 parallel serial output ports, enabling each clock signal to read 16 input and 16 output signals simultaneously. Each channel is configured with 32 serial port signal data. With 32 clocks, the port signals of 1024 points can be read and written. Adding port latching and loading, 34 clocks are required for each scan cycle. The multi-channel serial data port synchronous clock sequence generator uses the internal advanced timer PWM function of the processor, greatly reducing the processor load and improving the processor's computing power. The speed of the clock determines the latency time of the port, and the distance from the port to the main control determines the clock time. For every 300-meter distance, the round-trip time of light is approximately 2uS. Within this distance range, the clock speed can reach 200kHz, and the latency is approximately 34 clock times, totaling 0.17mS. The overall latency within 1500 meters is less than 1mS.

[0024] The above are only illustrative specific embodiments of the present invention and are not intended to limit the scope of the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A general interface programmable controller, which consists of 1 CPU board and 16 groups of IO boards, is characterized in that: The current sensor signal of the power circuit is also connected to the CPU board. The CPU board is laid out in the middle of the welding workshop, and the IO boards are scattered in the grouped welding machine areas. The input end of the CPU board is connected to 16 groups of IO through network cable interfaces. Each network cable interface has 4 pairs of differential signal lines, namely differential input interface, differential output interface, differential clock signal, and differential latch signal. There is also an output board. The output board decodes and encodes 4 groups of differential signals from the output end of the CPU board and then connects 32 welding machines. The monitoring computer is connected to the CPU board using a 485 bus.

2. The general interface programmable controller according to claim 1, wherein: The differential signal lines use twisted pair signal lines with a characteristic impedance of 50 ohms, and the line drive circuit uses 25LS32 or 26LV32.

3. The general interface programmable controller according to claim 1, characterized in that: The main control CPU of the CPU board uses an ARM architecture processor.

4. The general interface programmable controller according to claim 1, characterized in that: Each output port independently leads out 2 isolated normally open contact signal lines.

5. The general interface programmable controller according to claim 1, characterized in that: The CPU board circuit includes a CPU with an ARM core and a chip 2003A. The output pins of the CPU are connected to the corresponding input pins of chips U17 and 2003A.

6. The general interface programmable controller according to claim 1, wherein: The IO board circuit includes a chip RJ45A8, 2 chips AM26LS32, and 6 chips AM26LS31. The 6 chips AM26LS31 are respectively connected to the corresponding pins of the chip RJ45A8, and the 2 chips AM26LS32 are connected through multiple resistors.

7. A general interface programmable controller according to claim 1, characterized in that: The output board includes 1 chip AM26LS31 and 1 chip AM26LS32. 4 of the 8 chips HC165 are connected in series and then connected to the chip AM26LS31, and the other 4 chips HC165 are respectively connected to the chip AM26LS32. Chip 2003A is respectively set for connection. The 7th pin of the 4 chips HC165 connected to the chip AM26LS32 is also respectively connected to another chip 2003A, and the 13th pin is also respectively connected to the 3rd pin of the same clock chip 555.

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