CN201138592Y - Magnetizing and demagnetizing controller for electric permanent magnet attraction disc - Google Patents
Magnetizing and demagnetizing controller for electric permanent magnet attraction disc Download PDFInfo
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- CN201138592Y CN201138592Y CNU2007200363778U CN200720036377U CN201138592Y CN 201138592 Y CN201138592 Y CN 201138592Y CN U2007200363778 U CNU2007200363778 U CN U2007200363778U CN 200720036377 U CN200720036377 U CN 200720036377U CN 201138592 Y CN201138592 Y CN 201138592Y
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Abstract
The utility model relates to a magnet charging and demagnetization controller for an electric permanent magnet cupula; the controller has the advantages of high control precision, high trigger reliability, less interference, small size, being convenient to be mounted and connected, high trigger point capacity as well as perfect detecting and protecting alarm functions. The controller includes a micro-processing controller, a power circuit device, a photoelectric isolating circuit device for inputting a control signal, a parameter setting circuit device, a magnet charging and demagnetization current measuring circuit device, a controllable silicon and trigger drive circuit device, a large power magnet maintaining relay and drive circuit device, a working state relay drive circuit device and a digital display drive circuit device; the utility model is characterized in that the magnet charging and demagnetization current measuring circuit device includes an analog integrator consisting of a full load output operational amplifier OPA 335 and a R(2), a R(6) and a C(1); a current measuring loop differential current sensor and an 1/2 analog power voltage consisting of a R(4), a R(5), a C(2) and a C(3); the controllable silicon and trigger drive circuit device adopts a controllable silicon trigger mode by connecting photo-controllable silicon in series; the relay and the relays in the drive circuit device and a working state feed back relay circuit device are magnetic remaining relays.
Description
(1) technical field
The utility model relates to the parts of electric permanent-magnet suction disc, is specially electrically permanent magnet cupula magnetizing and demagnetizing controller.
(2) background technology
Electric permanent-magnet suction disc is the renewal product of traditional electrical magnetic-disc, and its functional characteristics is as long as through after magnetizing, just can keep magnetic attraction for a long time, and the time spent can not removed magnetic attraction by demagnetization.Only magnetize or the demagnetization process in just need energising, operating state need not switched at ordinary times, so both can reduce coil heating and cause workpiece deformation, can save a large amount of electric energy again, can also avoid pulling, being out of shape of magnechuck and workpiece by the control size that intensity regulates its electromagnetic attraction that magnetizes.Electrically permanent magnet cupula magnetizing and demagnetizing controller is one of core component of electric permanent-magnet suction disc indispensability, and its performance quality directly affects the overall performance of electric permanent-magnet suction disc and safe in utilization.Traditional electrically permanent magnet cupula magnetizing and demagnetizing controller has following shortcoming: 1, its SCR control circuit adopts the sawtooth waveforms triggering form relatively of control voltage and synchronized, and the silicon controlled angle of flow is bigger with the mains frequency fluctuation, has influenced control precision.Silicon controlled triggers and often applies pulse current by pulse transformer between the SCR control utmost point and negative electrode, very easily causes electrical Interference and false triggering; 2. its power commutation circuit, often adopt electromagnetic relay as diverter switch, not only volume is big, cost is high but also contact capacity is limited, maximum contact capacity average current has only 25A during 250VAC, can not guarantee to fill the reliability service of demagnetization peak current up to the large tracts of land electric permanent-magnet suction disc more than the 60A; 3. it has the function that simply magnetizes, and when there are short circuit in supply voltage catastrophic fluctuation or electric permanent-magnet suction disc circuit, open circuit, during the cable connector loose contact, can not effectively detect and report to the police, very easily causes security incident.
(3) summary of the invention
At the problems referred to above; the utility model provides a kind of electrically permanent magnet cupula magnetizing and demagnetizing controller; have control precision height, silicon controlled reliable trigger height, disturb advantages such as little; and volume is little, easy-to-connect, contact capacity height are installed; guaranteed the reliability of power commutation circuit; have perfect detection and protection warning function, avoid electric permanent-magnet suction disc under the state that magnetizes unusually, to work, improved its job security.
Its technical scheme is such: it comprises microprocessor controller, power circuit device, control signal input photoelectric isolating circuit device, the parameter setting circuit arrangement, fill demagnetization current measuring circuit device, controllable silicon and triggering driving circuit device, power magnetic force keeping relay and driving circuit device, operating state relay drive circuit device, digital display driver circuit device, it is characterized in that: the described pulse current connecting line of in the demagnetization current measuring circuit device high-power silicon controlled rectifier being exported that fills passes in Rogowski coil CT1, be connected to the contact input common port of high-power switching magnetic latching relay, resistor R 4 is connected with R5, the other end of R4 is connected to power supply VCC, the other end of R5 is connected to power supply ground, capacitor C2, C3 respectively with R4, the R5 parallel connection, because R4 is identical with the C3 parameter with R5 and C2, one 1/2 virtual power supply voltage has just been formed in R4 and R5 junction like this, the induced signal output negative terminal of Rogowski coil CT1 is connected on this virtual power supply voltage of 1/2 and connects 3 pin (in-phase input end) of moving operational amplifier U1A by resistance R 3, the induced signal output plus terminal of Rogowski coil CT1 is by the integrating resistor R6 of series connection, R2 is connected to 2 pin (inverting input) of operational amplifier U1A, integrating condenser C1 is connected between 6 pin (signal output part) of the 2 pin inverting inputs of operational amplifier U1A and operational amplifier U1A, the resistance R 1 that is used to eliminate the accumulated error that amplifier imbalance etc. causes is in parallel with capacitor C1, the 6 pin output signals of operational amplifier U1A are connected to the input of A/D analog to digital converter, 7 pin (power supply+) of operational amplifier U1A, 4 pin (power supply-) respectively with power supply VCC, power supply ground connects; In controllable silicon and the triggering driving circuit device, resistance R 11 is connected between the pulse output CF end and triode Q3 base stage of microprocessor controller, the emitter of Q3 connects the light-emitting diodes tube cathode that power supply ground collector electrode is connected to light activated power thyristor U12, the light-emitting diodes tube anode of U12 is connected with the light-emitting diodes tube cathode of light activated power thyristor U11, current-limiting resistance R12 is serially connected between the light-emitting diodes tube anode of power supply VCC and U11, the photosensitive controllable silicon anode of U11 is connected to the control utmost point of high-power silicon controlled rectifier module Q2, the photosensitive controllable silicon negative electrode of U11 is connected with the photosensitive controllable silicon anode of U12, the photosensitive controllable silicon negative electrode of U12 is connected in series to the control utmost point of high-power silicon controlled rectifier module Q1 by current-limiting resistance R6, grading resistor R13, R14 is connected in parallel on photosensitive controllable silicon the moon of U11 and U12 respectively, between the anode, disturb suppression capacitor C11, C12 is connected in parallel on respectively between the negative electrode and the control utmost point of Q1 and Q2, with the anode of Q1 and the A end that is connected to AC power after the negative electrode of Q2 is related, the anode of Q2 is connected to the public input that power switches magnetic latching relay with passing Rogowski coil CT1 after the negative electrode of Q1 is related, is parallel to the moon of Q1 and Q2 after being used for capacitor C13 that surge absorbs and resistor R 16 being connected again, anode; Relay and driving circuit device, in the operating state feedback relay circuit device, described relay is a magnetic latching relay, one end of the power contact of magnetic latching relay Kcom is connected to AC power one end, the other end is connected to the common port of electric permanent-magnet suction disc coil, magnetic latching relay K1, K2, K3 ... one end of the power contact of Kn passes the parallel connected end that Rogowski coil CT1 is connected to high-power silicon controlled rectifier module Q2 anode and Q1 negative electrode as common port, the other end is connected respectively to corresponding electric permanent- magnet suction disc 1,2,3 ... the input of n coil, magnetic latching relay K1, K2, K3 ... the Kn control coil is connected respectively to corresponding drive circuit of magnetic latching relay.
In the said structure of the present utility model; it is wide that current measurement coil differential current sensor Rogowski coil has measuring range; the precision height; reliable and stable; response band is wide; have simultaneously and measure and the relaying protection function; volume is little; in light weight; safety; the controllable silicon of light activated power thyristor series connection triggers form; it is big with the volume that pulse transformer exists to have avoided traditional controllable silicon to trigger rice; the power consumption height; the problem that electromagnetic interference is serious, magnetic latching relay substitutes the common electrical magnetic relay, and the power that is applied to the electrically permanent magnet cupula magnetizing and demagnetizing coil switches; make contact capacity be increased to 60A/400VAC, and volume reduce half by original maximum 25A/250VAC.
(4) description of drawings
Fig. 1 is the utility model principle schematic;
Fig. 2 is for filling the electrical schematic diagram of demagnetization current measuring circuit device in the utility model;
Fig. 3 is a controllable silicon and trigger the electrical schematic diagram of driving circuit device in the utility model.
(5) embodiment
See Fig. 1, the utility model comprises microprocessor controller 18, power circuit device 1, control signal input photoelectric isolating circuit device 2, parameter setting circuit arrangement 3, fill demagnetization current measuring circuit device 17, controllable silicon and triggering driving circuit device 16, power magnetic force keeping relay and driving circuit device 15, operating state relay drive circuit device 8, digital display driver circuit device 7, see Fig. 2, filling the pulse current connecting line of in the demagnetization current measuring circuit device high-power silicon controlled rectifier being exported passes in Rogowski coil CT1, be connected to the contact input common port of high-power switching magnetic latching relay, resistor R 4 is connected with R5, the other end of R4 is connected to power supply VCC, the other end of R5 is connected to power supply ground, capacitor C2, C3 respectively with R4, the R5 parallel connection, because R4 is identical with the C3 parameter with R5 and C2, one 1/2 virtual power supply voltage has just been formed in R4 and R5 junction like this, the induced signal output negative terminal of Rogowski coil CT1 is connected on this virtual power supply voltage of 1/2 and connects 3 pin (in-phase input end) of moving operational amplifier U1A by resistance R 3, the induced signal output plus terminal of Rogowski coil CT1 is by the integrating resistor R6 of series connection, R2 is connected to 2 pin (inverting input) of operational amplifier U1A, integrating condenser C1 is connected between 6 pin (signal output part) of the 2 pin inverting inputs of operational amplifier U1A and operational amplifier U1A, the resistance R 1 that is used to eliminate the accumulated error that amplifier imbalance etc. causes is in parallel with capacitor C1, the 6 pin output signals of operational amplifier U1A are connected to the input of A/D analog to digital converter, 7 pin (power supply+) of operational amplifier U1A, 4 pin (power supply-) respectively with power supply VCC, power supply ground connects; See Fig. 3, in controllable silicon and the triggering driving circuit device, resistance R 11 is connected between the pulse output CF end and triode Q3 base stage of microprocessor controller, the emitter of Q3 connects the light-emitting diodes tube cathode that power supply ground collector electrode is connected to light activated power thyristor U12, the light-emitting diodes tube anode of U12 is connected with the light-emitting diodes tube cathode of light activated power thyristor U11, current-limiting resistance R12 is serially connected between the light-emitting diodes tube anode of power supply VCC and U11, the photosensitive controllable silicon anode of U11 is connected to the control utmost point of high-power silicon controlled rectifier module Q2, the photosensitive controllable silicon negative electrode of U11 is connected with the photosensitive controllable silicon anode of U12, the photosensitive controllable silicon negative electrode of U12 is connected in series to the control utmost point of high-power silicon controlled rectifier module Q1 by current-limiting resistance R6, grading resistor R13, R14 is connected in parallel on photosensitive controllable silicon the moon of U11 and U12 respectively, between the anode, disturb suppression capacitor C11, C12 is connected in parallel on respectively between the negative electrode and the control utmost point of Q1 and Q2, with the anode of Q1 and the A end that is connected to AC power after the negative electrode of Q2 is related, the anode of Q2 is connected to the public input that power switches magnetic latching relay with passing Rogowski coil CT1 after the negative electrode of Q1 is related, is parallel to the moon of Q1 and Q2 after being used for capacitor C13 that surge absorbs and resistor R 16 being connected again, anode; Relay and driving circuit device, in the operating state feedback relay circuit device, described relay is a magnetic latching relay, one end of the power contact of magnetic latching relay Kcom is connected to AC power one end, the other end is connected to the common port of electric permanent-magnet suction disc coil, magnetic latching relay K1, K2, K3 ... one end of the power contact of Kn passes the parallel connected end that Rogowski coil CT1 is connected to high-power silicon controlled rectifier module Q2 anode and Q1 negative electrode as common port, the other end is connected respectively to corresponding electric permanent- magnet suction disc 1,2,3 ... the input of n coil, magnetic latching relay K1, K2, K3 ... the Kn control coil is connected respectively to corresponding drive circuit of magnetic latching relay.Describe control procedure of the present utility model below in conjunction with Fig. 1: microprocessor controller 18 receives the AC synchronous signal of power circuit device 1, realizes the phase-locked and AC synchronous tracking of numeral; Receive the instruction of control signal input photoelectric isolating circuit device 2, control electric permanent-magnet suction disc a (see figure 2) is finished the magnetization, demagnetization function; According to the set point of parameter setting circuit arrangement 3, the maximum protection that fills demagnetization intensity, fills the demagnetization umber of pulse and fill demagnetization of determining electric permanent-magnet suction disc a is reported to the police and minimum alarm current (among Fig. 14 be overcurrent, undercurrent device for fill demagnetize pulse regulation device, 6 for filling demagnetization intensity adjustments device, 5); By reading the current value that fills the electrically permanent magnet cupula magnetizing and demagnetizing that demagnetization current measuring circuit device 17 gathers, judge filling demagnetization and whether being in normal condition of electric permanent-magnet suction disc, protection and warning can be provided when unusual; Export phase shift triggering signal accurately, by controllable silicon and trigger that driving circuit device 16 controls the silicon controlled angle of flow and electric permanent-magnet suction disc reliably fill demagnetization intensity; By power magnetic force keeping relay and driving circuit device 15 control power magnetic force keeping relay, realize that the demagnetization of filling of many groups coil of electric permanent-magnet suction disc is automaticallyed switch; The operating state of electric permanent-magnet suction disc is outputed on the operating state feedback relay feedback information of robot control system(RCS)s such as realization and PLC; Operating state with every setup parameter and electric permanent-magnet suction disc respectively fill degaussion coil realizes digital the demonstration by digital display driver circuit device 7, finishes man-machine information exchange; The current measurement coil differential current sensor that fills in the demagnetization current measuring circuit device 17 is the loop coil of a uniform winding on nonferromugnetic material.Output signal is the electric current time differential, carries out the circuit of integration by a voltage signal to output, just can truly reduce input current.Because be nonferrous magnetic material, so there is not hysteresis effect, phase error is almost nil; No magnetic saturation phenomenon, thereby measuring range can be from several amperes to hundreds of kiloampere electric currents; Simple in structure, and and tested electric current between do not have the contact of direct circuit; The wide 0.1Hz-1MHz of response band.Compare with traditional instrument transformer of ribbon core, it is wide that the Rogowski coil has measuring range, the precision height, and reliable and stable, response band is wide, has simultaneously to measure and the relaying protection function, and volume is little, in light weight, safety and compliance with environmental protection requirements.Current measurement based on the Rogowski coil has the advantages that response speed soon, not can saturated, almost have phase error, so it is highly suitable for the big impulse current measurement of electrically permanent magnet cupula magnetizing and demagnetizing coil.Its operation principle is as shown in Figure 2: analogue integrator is reduced into the induced potential (to filling the signal of demagnetization current and time diffusion (di/dt)) of Rogowski coil CT1 and fills the demagnetization current signal, send microprocessor to calculate after the A/D conversion.Among Fig. 2, R4, R5, C2, C3 form 1/2 virtual power supply voltage, and R1 is used to eliminate the accumulated error that amplifier imbalance etc. causes, when filling demagnetization current and be zero, it is 1/2 supply voltage that the integrator transmission of electricity is pressed.See Fig. 3, the controllable silicon trigger process of light activated power thyristor series connection, be subjected to the triggering signal of microprocessor controller 18 when the CF termination, triode Q3 conducting, light activated power thyristor U11, U12 be triggering and conducting simultaneously, and high-power silicon controlled rectifier Q1, the Q2 control utmost point obtains trigger current, Q1 conducting when alternating current is in positive half wave, be in the operating state that magnetizes, the Q2 conducting is in the demagnetization operating state when alternating current is in negative half-wave.R13, R14 are grading resistor among Fig. 3, and R15 is a current-limiting resistance, and C11, C12 suppress electric capacity for disturbing, and C13, R16 are used to fill the surge absorption in demagnetization loop.The power that magnetic latching relay is applied to the electrically permanent magnet cupula magnetizing and demagnetizing coil switches, and make contact capacity be increased to 60A/400VAC by original maximum 25A/250VAC, and volume reduces half.9 finish feedback signal passage, 11 and finish the feedback signal passage for magnetizing for demagnetization for fault feedback signal passage, 10 among Fig. 1; 12,13,14 be respectively output channel; 19 are the control input of magnetizing; 20 are demagnetization control input; 21 separate the lock control input.
Claims (1)
1, electrically permanent magnet cupula magnetizing and demagnetizing controller, it comprises microprocessor controller, power circuit device, control signal input photoelectric isolating circuit device, the parameter setting circuit arrangement, fill demagnetization current measuring circuit device, controllable silicon and triggering driving circuit device, power magnetic force keeping relay and driving circuit device, operating state relay drive circuit device, digital display driver circuit device, it is characterized in that: the described pulse current connecting line of in the demagnetization current measuring circuit device high-power silicon controlled rectifier being exported that fills passes in Rogowski coil CT (1), be connected to the contact input common port of high-power switching magnetic latching relay, resistor R 4 is connected with R5, the other end of R (4) is connected to power supply VCC, the other end of R (5) is connected to power supply ground, capacitor C (2), C (3) respectively with R (4), R (5) parallel connection, the induced signal output negative terminal of Rogowski coil CT (1) is connected on this virtual power supply voltage of 1/2 and connects 3 pin that move operational amplifier U1A by resistance R (3) is in-phase input end, the induced signal output plus terminal of Rogowski coil CT (1) is by the integrating resistor R (6) of series connection, 2 pin that R (2) is connected to operational amplifier U1A are inverting input, integrating condenser C (1) is connected to the 2 pin inverting inputs of operational amplifier U1A and 6 pin of operational amplifier U1A are between the signal output part, the resistance R (1) that is used to eliminate the accumulated error that amplifier imbalance etc. causes is in parallel with capacitor C (1), the 6 pin output signals of operational amplifier U1A are connected to the input of A/D analog to digital converter, 7 pin of operational amplifier U1A be power supply+, 4 pin are power supply-respectively and power supply VCC, power supply ground connects; In controllable silicon and the triggering driving circuit device, resistance R (11) is connected between the pulse output CF end and triode Q (3) base stage of microprocessor controller, the emitter of Q (3) connects the light-emitting diodes tube cathode that power supply ground collector electrode is connected to light activated power thyristor U (12), the light-emitting diodes tube anode of U (12) is connected with the light-emitting diodes tube cathode of light activated power thyristor U (11), current-limiting resistance R (12) is serially connected between the light-emitting diodes tube anode of power supply VCC and U (11), the photosensitive controllable silicon anode of U (11) is connected to the control utmost point of high-power silicon controlled rectifier module Q (2), the photosensitive controllable silicon negative electrode of U (11) is connected with the photosensitive controllable silicon anode of U (12), the photosensitive controllable silicon negative electrode of U (12) is connected in series to the control utmost point of high-power silicon controlled rectifier module Q (1) by current-limiting resistance R (6), grading resistor R (13), R (14) is connected in parallel on photosensitive controllable silicon the moon of U (11) and U (12) respectively, between the anode, disturb suppression capacitor C (11), C (12) is connected in parallel on respectively between the negative electrode and the control utmost point of Q (1) and Q (2), with the anode of Q (1) and the A end that is connected to AC power after the negative electrode of Q (2) is related, the anode of Q (2) is connected to the public input that power switches magnetic latching relay with passing Rogowski coil CT1 after the negative electrode of Q (1) is related, is parallel to the moon of Q (1) and Q (2) after being used for capacitor C (13) that surge absorbs and resistor R (16) being connected again, anode; Relay and driving circuit device, in the operating state feedback relay circuit device, described relay is a magnetic latching relay, one end of the power contact of magnetic latching relay Kcom is connected to AC power one end, the other end is connected to the common port of electric permanent-magnet suction disc coil, magnetic latching relay K (1), K (2), K (3) ... one end of the power contact of K (n) passes the parallel connected end that Rogowski coil CT (1) is connected to high-power silicon controlled rectifier module Q (2) anode and Q (1) negative electrode as common port, the other end is connected respectively to corresponding electric permanent-magnet suction disc 1,2,3 ... the input of n coil, magnetic latching relay K (1), K (2), K (3) ... K (n) control coil is connected respectively to corresponding drive circuit of magnetic latching relay.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007200363778U CN201138592Y (en) | 2007-04-11 | 2007-04-11 | Magnetizing and demagnetizing controller for electric permanent magnet attraction disc |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007200363778U CN201138592Y (en) | 2007-04-11 | 2007-04-11 | Magnetizing and demagnetizing controller for electric permanent magnet attraction disc |
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| Publication Number | Publication Date |
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| CN201138592Y true CN201138592Y (en) | 2008-10-22 |
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| CNU2007200363778U Expired - Fee Related CN201138592Y (en) | 2007-04-11 | 2007-04-11 | Magnetizing and demagnetizing controller for electric permanent magnet attraction disc |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20220170965A1 (en) * | 2020-12-02 | 2022-06-02 | Hyundai Mobis Co., Ltd. | Apparatus and method for compensating for offset in switching current sensing |
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2007
- 2007-04-11 CN CNU2007200363778U patent/CN201138592Y/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20220170965A1 (en) * | 2020-12-02 | 2022-06-02 | Hyundai Mobis Co., Ltd. | Apparatus and method for compensating for offset in switching current sensing |
| US11940473B2 (en) * | 2020-12-02 | 2024-03-26 | Hyundai Mobis Co., Ltd. | Apparatus and method for compensating for offset in switching current sensing |
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| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20081022 Termination date: 20120411 |