Introduction
In the actual production process, must use frequently to have the automatic reverse forced reversing function control portion, like in machine-finishing’s shuttle operation (displacement), direct-current power supply’s forward and reverse output, the electric motor is reversing phenomena and so on movement, is when to (or reverse) is moving to one is fixed time certain once in a while the position, automatically trades for reverse (or to) is moving, process again and again. Realizes this process automation, designs a set of control circuit, matches the position transmitter or the time relay again. At present although the market existing time relay may use many combinations to satisfy some use situation the request, but still has the redundant timing error to be big, the stable reliability service is not high, uses nimble and so on questions not conveniently. Therefore, the author has researched and developed take the monolithic integrated circuit as core composition time/displacement reversing controller SWHX-1, this system has the cost low status characteristic, may and overcomes the above insufficiency completely.
Electric circuit composition and principle of work
SWHX-1 internal circuit as shown in Figure 1. This system divides into the input output electrical signal to transform, the CPU software programming control and fixed time the time delay to establish three parts, the entire electric circuit altogether has 14 lead-out wires, 2, 3, 4 feet public carry VGND for the direct-current grounding. This component available alternating and direct two kind of power supply way work. When with exchange power supply, through the pin 13, 14 inputs exchanges 12 V, after bridge-type rectification, constant voltage the supplies internal circuit constant pressure datum power source, after and 12 V passes through the rectification cocurrent the pin 1, 2, 3, 4 to send out, supplies the exterior other electric circuit use; When with direct-current power supply, the pin 1, 2, 3, 4 pieces become the input end, the input 12V DC voltage after the constant voltage supplies the internal circuit again, this way may omit the alternating current supply, but must pay attention the pin 14, 13 puts in the hanging condition.
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| Figure 1 time/displacement commutator electric circuit schematic diagram |
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The SWHX-1 internal circuit design has 1 group commutation time delay and 2 groups fixed time outputs, the commutation delay time is points out mistakes after (either reverse) outputs the group shuts off time delay period of time only then clears reverse (or) the group work time, the user may establish willfully between 0.5~2s; 2 groups fixed time time respectively are point out mistakes the operating time which outputs to and the reverse group, the user may between 1m~7h31m establish willfully. If the 1m~7h31m time fixed time cannot satisfy time the operation requirements, in addition leaves leeway 4 port P1~P4, but the external connection 4 time relays or 4 limit switches make up. Pl and P3 are the forward group, P2 and P4 are the reverse groups.
◇ delay time hypothesis
(1) delay time hypothesis law
Figure 1 t0~t4 is the commutation delay time hypothesis pipe nipple switch, t0 is to the place public end, t1~t4 with 0.5 s, 1 s, 1.5 s, 2 s corresponds separately, when the two pipe nipple, may realize the corresponding commutation time delay through the CPU software programming. When for example t0 and t1 pipe nipple, the time delay is 0.5 s; when t0 and t3 pipe nipple, the time delay is 1.5 s.
(2) fixed time time setting law
Figure 1 S1 and S2 are 8 fixed time time settings dial the position switch, each switch first three are the hour positions, latter 5 for a minute position, use the binary system encoding method, when after 8 dial the code designation, sends in through CPU P1 and the P2 mouth, after the software programming control, realizes the corresponding function fixed time. Therefore each road’s time fixed time may establish willfully between 1m 7h31m.
◇ fixed time commutator’s principle of work
When SWHX one 1 uses makes fixed time the reverse control, CPU first reads in dials position switch S the setting value fixed time, realizes after the software programming recognition and through the CPU interior timer and the software time delay, when fixed time time, through the P0 mouth after the pin 12, 11 will send out one fixed time to arrive at the pulse, when pin 12, 11 separately with 5, 7 foot pipe nipples, this will fixed time arrive at the pulse to produce an interrupt request signal to CPU, after CPU will receive this interrupt request, will output a blockade electric potential signal through the pin Vs1 port, stops presently a group which will work, and after 0.5~2 s time delay, outputs a start signal through the pin Vs2 port, starts another group to start to work, thus completes a commutation action cycle. Vice versa, starts once again.
◇ makes the displacement commutator’s principle of work
When SWHX one 1 uses makes the displacement reverse control, the above fixed time function will not have an effect, but will move examines the sensor (for limit switch to send generally) “moves” the signal through the pin 5, 7 ports to send out the interrupt request to CPU, when after CPU receives this interrupt request signal, then completes the above commutation work process. Moreover, pin 6; 8th, uses in moving limits, because in the overwhelming majority actual production process’s displacement has the limit, therefore sends out the spacing sensor the signal after the port 6, 8 sends, CPU after receiving this request signal, through the pin 9, 10 sends out the spacing blockade signal immediately, stops the displacement work.
Software design
The SWHX-1 software routine divides into the initialization, fixed time distinguishes and time delay processing and the interrupt commutation processes three parts, its procedure flow as shown in Figure 2.
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Cyclical commutation power source application
In many production processes must use the periodicity to commutate the electrical power unit. Here only as regularly explains its application method take the common galvanization power source’s in one kind. Shown in Figure 3 for the three-phase double zed star type bidirectional 6 pulse wave cycle commutation power source’s electric circuit schematic diagram. This power source uses two set of thyristor silicon-controlled rectifier leveling circuit, but under the SWHX-1 control, can only have set of work during the same period of time, other set is blocked the closure. Two set of leveling circuit’s operating time may S1 and S2 establishes separately through Figure 1. Figure 3 CF97088B is the double zed star type 6 pulse wave thyristor triggering special-purpose component, it besides produces 6 synchronization trigger pulse, the interior also has the electric current, the voltage double P1 negative feedback adjustment function, and can also in the automatic diagnosis input three-phase electricity lack, as well as the overvoltage protection, crosses functions and so on current limitation, when has these phenomena occur, the system may the holding trigger pulse output, by have the protection and the limit goal. W1 and W3 respectively be forward and reverse output voltage setting value adjusting knob, but W2 and W4 respectively be forward and reverse output voltage feedback quantity adjusting knob.
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This power circuit’s merit is the structure is simple, is advantageous for the assembly, the debugging and on-site maintenance. Because CF97088 and SWHX one 1 is the entire sealed component, therefore may use in galvanizing, in the electrolysis and the chemical industry.
In moves in the electric drive application
In the machine-finishing production process, has the round-trip displacement movement process frequently, reflected that is the electric motor is reversing the phenomenon to the electric appliance transmission part’s work phenomenon, here only digs, the milling machine take common Dragon Gate as regularly to explain a SWHX 1 application. Figure 4 digs, the milling machine cocurrent liang salary proper far commutator circuit schematic diagram example. In chart S1 and S2 are reversing the limit switch, S3 and S4 are the spacing limit switches. When the forward displacement bumps touches switch S1, under a SWHX 1 control, after time delay 0.5~2 s, trades automatically for the reverse movement, when moves bumps touches S2, also automatically trades for the forward movement, starts once again. The displacement bumps touches switch S3 or S4 may use in indicating that moves ultra receives limits, closes the output immediately under a SWHX 1 control, stops the displacement movement.
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Concluding remark
Will substitute for the present timer and the time relay based on monolithic integrated circuit’s control is present’s development direction, a SWHX 1 component which this article introduced may take an attempt. This component’s indicated in cyclical commutation power source application result that this controller fixed time is fixed time precise, the movement is reliable, the effect is good.
