CN201854462U

CN201854462U - Electromagnetic induction heater

Info

Publication number: CN201854462U
Application number: CN2010205974746U
Authority: CN
Inventors: 赵崇赛; 赵仁翁
Original assignee: WENZHOU YALEFEI ELECTRONIC TECHNOLOGY Co Ltd
Current assignee: WENZHOU YALEFEI ELECTRONIC TECHNOLOGY Co Ltd
Priority date: 2010-11-09
Filing date: 2010-11-09
Publication date: 2011-06-01
Anticipated expiration: 2020-11-09

Abstract

The utility model discloses an electromagnetic induction heater, which comprises a nozzle, a machine barrel, an electromagnetic coil and a controller, wherein the nozzle is position at one end of the machine barrel, and the electromagnetic coil is wound on the machine barrel; and the controller is connected with the electromagnetic coil. Compared with a heating coil mode, the heat loss is relatively reduced, and the danger of high-temperature scalding does not occur.

Description

Electromagnetic induction heater

Technical field

The utility model relates to a kind of heater, particularly a kind of electromagnetic induction heater.

Background technology

The heater of traditional injection moulding machine is a resistance type heater, and as shown in Figure 1, resistance type heater comprises nozzle 1, machine barrel 2 and heating circle 3, and heating circle 3 generates heat, and heat contacts with the surface of machine barrel 2 by heating circle 3 again, carries out the heat transmission; In heat transfer process, the outside spatial diffusion of temperature of heating circle outer ring, ambient temperature constantly raises.

But a part of heat of resistance type heater is dispersed into the space from heating circle outer surface, causes energy waste.And the surface temperature of heating circle is high, and the danger of being scalded by high temperature is arranged.In addition, the heat of resistance type heater is to be delivered to by heat exchange pattern to be heated device, and firing rate is slow, and thermal resistance is very big, and efficient is lower.

Summary of the invention

Technical problem to be solved in the utility model provides a kind of electromagnetic induction heater, and its circle mode of generating heat relatively aspect thermal loss reduces, the danger that does not have high temperature to scald.

For solveing the technical problem, the utility model provides a kind of electromagnetic induction heater, it is characterized in that, it comprises nozzle, machine barrel, solenoid, controller, nozzle is positioned at an end of machine barrel, and solenoid is wrapped on the machine barrel, and controller is connected with solenoid.

Preferably, described controller comprises the AC-DC translation circuit, the DC-AC translation circuit, synchronizing signal and high-frequency current testing circuit, IGBT drives and short-circuit detecting circuit, control circuit, the power current testing circuit, accessory power supply and voltage detecting circuit, microprocessor, AC-DC translation circuit and DC-AC translation circuit, the power current testing circuit, accessory power supply and voltage detecting circuit connect, the DC-AC translation circuit is connected with synchronizing signal and high-frequency current testing circuit, the high-frequency current testing circuit is connected with control circuit, and IGBT drives and short-circuit detecting circuit, the power current testing circuit, accessory power supply and voltage detecting circuit are connected with microprocessor.

Positive progressive effect of the present utility model is: after the solenoid in the utility model feeds high-frequency current, demand side does not carry out heat transmission with contacting of face, but pass through metal barrel and screw rod by high-frequency alternating magnetic field, make and himself induce very big electric current eddy current, thereby heating, and the circle mode of generating heat relatively aspect thermal loss reduces, and ambient temperature improves significantly.

Description of drawings

Fig. 1 is the structural representation of existing resistance type heater.

Fig. 2 is the structural representation of the utility model electromagnetic induction heater.

Fig. 3 is the theory diagram of the utility model middle controller.

Fig. 4 is the circuit diagram of AC-DC translation circuit in the utility model.

Fig. 5 is the circuit diagram of DC-AC translation circuit in the utility model.

Fig. 6 is the circuit diagram of synchronizing signal and high-frequency current testing circuit in the utility model.

Fig. 7 is that IGBT drives and the circuit diagram of short-circuit detecting circuit in the utility model.

Fig. 8 is the circuit diagram of control circuit in the utility model.

Fig. 9 is the circuit diagram of power current testing circuit in the utility model.

Figure 10 is the circuit diagram of accessory power supply and voltage detecting circuit in the utility model.

Embodiment

Lift a preferred embodiment below, and come the clearer the utility model that intactly illustrates in conjunction with the accompanying drawings.

As shown in Figure 2, the utility model electromagnetic induction heater comprises nozzle 11, machine barrel 12, solenoid 13 and controller 14, and nozzle 11 is positioned at an end of machine barrel 12, and solenoid 13 is wrapped on the machine barrel 12, and controller 14 is connected with solenoid 13.

As shown in Figure 3, controller 14 comprises AC-DC translation circuit 21, DC-AC translation circuit 22, synchronizing signal and high-frequency current testing circuit 23, IGBT(Insulated Gate Bipolar Transistor, igbt) driving and short-circuit detecting circuit 24, control circuit 25, power current testing circuit 26, accessory power supply and voltage detecting circuit 27, microprocessor 28, AC-DC translation circuit 21 and DC-AC translation circuit 22, power current testing circuit 26, accessory power supply and voltage detecting circuit 27 connect, DC-AC translation circuit 22 is connected with synchronizing signal and high-frequency current testing circuit 23, high-frequency current testing circuit 23 is connected with control circuit 25, and IGBT drives and short-circuit detecting circuit 24, power current testing circuit 26, accessory power supply and voltage detecting circuit 27 are connected with microprocessor 28.AC-DC translation circuit 21 is that civil power is converted to DC power supply, for follow-up DC-AC translation circuit 22 provides electric energy.DC-AC translation circuit 2 is the high frequency electric sources that DC power supply become 12 ~ 25KHz.Synchronizing signal and high-frequency current testing circuit 23 are for the DC-AC converter provides lockin signal, detect the intensity of high-frequency current simultaneously, for the protection of power adjustment and IGBT module provides foundation.IGBT drives and short-circuit detecting circuit 24 is to be that safety drives the requisite circuit of IGBT module, also has function of short circuit detection simultaneously, is short-circuited or output circuit cuts out the IGBT drive signal when meeting accident in load.And export a guard signal for microprocessor.Control circuit 25 control vibrations, phase-locked, PWM(Pulse Wavelength Modulation, pulse-width modulation) etc.Control circuit 25 is to guarantee that entire circuit is operated in the treatment circuit of optimum state, two-way pwm signal that includes the higher-order of oscillation and the tracking and the generation of phase of output signal had the dead band complementation etc.Power current testing circuit 26 is the intensity that is used for detecting power current, on the one hand as the foundation of adjusting power, when current anomaly, closes power output on the other hand.Accessory power supply and voltage detecting circuit 27 are for this circuit inside provides necessary low-voltage supply, as the DC(direct current of relay work) 15V, the DC15V that the IGBT drive circuit needs, the DC5V of microprocessor work etc.Another function of accessory power supply and voltage detecting circuit 27 work is to detect supply voltage, when supply voltage is unusual, exports a control signal and gives microprocessor.Microprocessor 28 is used to gather the information of related work state, and operation is dealt with and output alarm signal when the circuit abnormality.

As shown in Figure 4, the operation principle of AC-DC translation circuit 31 is as follows: power supply is behind X, Y, Z three road interface input circuits, wherein one insert three-phase bridge rectification bridge DB1 behind power frequency instrument transformer T3, the pi type filter that the output ripple direct current is formed via inductance L 1, capacitor C 12, capacitor C 14 becomes level and smooth relatively direct current.Finish the conversion of AD-DC.

As shown in Figure 5, the operation principle of DC-AC translation circuit 22 is as follows: IGBT module, capacitor C 4, capacitor C 7, magnet exciting coil (DUT1, DUT2) etc. are formed symmetrical expression semi-bridge alternation circuit.On the 4th and 6 pin driving grids of IGBT module, add the complementary PWM of the two-way that has the dead band.Two IGBT alternate conduction in the IGBT module.On magnet exciting coil, produce the high-frequency current of 15 ~ 25KHz.Producing eddy current near near the magnetic conduction workpiece the magnet exciting coil is inner, thereby making workpiece directly produce heat energy.

As shown in Figure 6, the operation principle of synchronizing signal and high-frequency current testing circuit 23 is as follows: HF current transformer T1 is converted to voltage signal with current signal, and this voltage signal also includes the phase information of IGBT work simultaneously.Phase information is exported to control circuit 25 by the 2nd pin of HF current transformer T1.High-frequency current signal is exported to control circuit 25 through resistance R 13 after resistance R 11, resistance R 12, capacitance D3, capacitance D4 conversion.

As shown in Figure 7, IGBT driving and short-circuit detecting circuit 24 be modularization, its operation principle is as follows: inner optocoupler and the main circuit of adopting of module M1 isolated, and imports the prime working power between the 2nd and 4 pin of module M1, drives two groups of power supplys of IGBT in the input of the 6th, 9,11,14 pin.The 3rd and 5 pin are the input of two-way pwm signal.The 8th and 13 pin output IGBT drive signal.The 10th and 15 pin are that short-circuit signal detects input pin.Finish the differentiation of short trouble in inside modules.And give microprocessor at the 3rd pin output short-circuit fault-signal.This module also has low pressure and detects, and falls defencive functions such as grid voltage, for the IGBT trouble free service provides strong guarantee.

As shown in Figure 8, control circuit 25 is modularization also, and its operation principle is as follows: the 2nd pin input sync signal of module M2, the 3rd pin input high-frequency current information.The 11st pin input power current information, the 12nd pin is the fault detect input pin.The 8th pin is the vibration control end.The 7th pin is a power adjustment end.After the 8th pin was received start signal, the inside modules oscillator was started working, and oscillator signal is finished dead band control in inside, complementary handle and under the cooperation of phase lock circuitry, at module the 9th and 10 pin output pwm signals.The two-way current signal that is input to inside modules is in inter-process.When detecting the overcurrent letter, in time close PWM output.Prevent unexpected the generation.

As shown in Figure 9, power current testing circuit 26 comprises capacitor C 16, resistance R 15 etc., and power current testing circuit 26 also is the current signal translation circuit that utilizes current transformer, and principle is similar with the frequency modulation current conversion circuit, describes no longer one by one here.

As shown in figure 10; the operation principle of accessory power supply and voltage detecting circuit 27 is as follows: three-phase alternating current two-phase wherein is through current protector FUSE; common mode is drawn up behind the inductance input three-phase bridge rectification bridge DB2, and to give triode Q1, inductance T2 be main subsequent conditioning circuit to the output high direct voltage behind interelectrode capacitance EC3 and interelectrode capacitance EC4 smothing filtering.Power module M3 finishes inside voltage detecting, current detecting, vibration, PWM pulse-width modulation.At module the 3rd pin output voltage abnormal signal, after isolating, optocoupler U6 sends into microprocessor.At the 5th pin output pwm signal.Drive subsequent conditioning circuit and finish the power conversion function.Line group 1 ~ 10, line group 8 ~ 9 provide power supply for behind rectifying and wave-filtering the IGBT driver module.Processing provides power supply to line group 6 ~ 7 to small-signals such as relay and microprocessors behind rectifying and wave-filtering.

Electromagnetic induction heating of the present utility model is to produce eddy current and generate heat being heated the magnetic conduction device inside by solenoid, and heat does not need conduction, so temperature rise is rapid.Generally all there is insulation material heat insulation between magnetic conduction device and the solenoid being heated, is heated the heat that the magnetic conduction device inside produces and is difficult for being diffused into the space, so efficient is higher.In addition, solenoid D.C. resistance because of self when work generates heat.The D.C. resistance of general solenoid is all very little, so the temperature rise of solenoid is lower, and the danger that does not have high temperature to scald.

After solenoid fed high-frequency current, demand side did not carry out heat transmission with contacting of face, but passes through metal barrel and screw rod by high-frequency alternating magnetic field, make himself inducing very big electric current eddy current, thus heating.The circle mode reduces and the thermal loss aspect generates heat relatively, and ambient temperature improves significantly.

Though more than described embodiment of the present utility model, but those skilled in the art is to be understood that, these only illustrate, and under the prerequisite that does not deviate from principle of the present utility model and essence, can make numerous variations or modification to these execution modes.Therefore, protection range of the present utility model is limited by appended claims.

Claims

1. an electromagnetic induction heater is characterized in that, it comprises nozzle, machine barrel, solenoid, controller, and nozzle is positioned at an end of machine barrel, and solenoid is wrapped on the machine barrel, and controller is connected with solenoid.

2. electromagnetic induction heater as claimed in claim 1, it is characterized in that, described controller comprises the AC-DC translation circuit, the DC-AC translation circuit, synchronizing signal and high-frequency current testing circuit, IGBT drives and short-circuit detecting circuit, control circuit, the power current testing circuit, accessory power supply and voltage detecting circuit, microprocessor, AC-DC translation circuit and DC-AC translation circuit, the power current testing circuit, accessory power supply and voltage detecting circuit connect, the DC-AC translation circuit is connected with synchronizing signal and high-frequency current testing circuit, the high-frequency current testing circuit is connected with control circuit, and IGBT drives and short-circuit detecting circuit, the power current testing circuit, accessory power supply and voltage detecting circuit are connected with microprocessor.