SU1022750A1 - Ultrasonic device for cleaning thermal units from deposits - Google Patents

Description

Yu Yu

 ate

The invention responds to ultrasonic technology and can be used to clean up deposits of internal and external heat transfer surfaces and channels of heat generating units in heat and power engineering, the food industry, on ships of river and sea fleets.

Ultrasonic devices for cleaning heat-generating units are known, which contain a magnetostriction transducer, a switching element, a storage capacitor, a power supply unit and a unit specifying the pulse frequency of the AC,

The closest to the proposed technical entity is an ultrasound device that includes a power source, a switching element, a pulse frequency block, a storage capacitor, a magnetostrictive converter, an excitation winding connected to the windings of a storage capacitor through a C21 switching circuit.

The disadvantage of these devices is the low excitation efficiency of the magnetostrictive converter, limiting their performance.

The purpose of the invention is to increase the productivity and efficiency of cleaning,

The goal is achieved by the fact that the ultrasonic device for cleaning the decontamination of deposits from deposits is provided with an additional excitation winding placed on the magnetostrictive transducer and disconnected according to the first excitation winding, the switching element and the control unit of the switching elements, while the additional winding of the capacitor is connected to the plates of the storage capacitor sequentially power & circuit additional switching element and the source of the lithane, and the output unit and the pulse frequency is connected to the input of the control unit of the switching elements, the outputs of which are respectively connected to the control circuits of the switching elements.

FIG. 1 shows a functional diagram of the device; in Fig. 2, the characteristic impurity diagrams of the control voltage of the switching elements C and U, the current through the storage capacitor l, the voltage on the winding of the converter Uj, and the oscillations of the converter face.

The device contains a power supply unit 1, the output of which through the power circuit of the additional switching element 2 and the additional excitation winding 3 is connected to the plates of the storage capacitor k, the plates of which also through the main winding 5 are connected to the power circuit of the main switching element 6, the output of the pulse frequency block 7 connected to the input of the control unit of the switching elements 8, the outputs of which are connected respectively to the control circuits of the additional 2 and main 6 switching elec- ENTOV.

The device works as follows.

The pulse frequency block 7 generates a pulse that triggers the control unit 8 with the switching elements. This block generates a control pulse U (plot a), which opens an additional switching element. 2, which connects the storage capacitor through the additional winding 3 of the converter to the output of the power supply unit 1, the storage capacitor A is charged with current flowing from the power supply through the additional switching element 2 and the winding 3 of the converter. Charging is oscillatory in nature and, on windings 3 and 5 of the converter, the voltage variation Ug is close to cosine (plot g). The force arising in the magnetostatic force (the pictorial material drives the oscillator system of the transducer. The oscillations are most intense at frequencies close to their own, determined by equivalent mass, elasticity and impedance of the transducer load. To increase the amplitude of the acoustic oscillations, the duration of the electrical excitation pulse is determined by windings 3 or 5 and the capacitor of the storage capacitor, taking into account the nonlinearity of the magnetostriction characteristics and the optimal values between the frequencies in the transient and is selected from 1 to 2 half-periods of the resonant frequency of the loaded transducer. At the time when current 1 decreases to zero (plot c), switching element 2 closes and the transducer oscillates freely. At this time, on the windings 3 and 5, a voltage is induced by the reverse magnetostrictive effect. At a time when the transducer oscillates through zero from a negative value to a positive one, the control unit 8 generates a trigger Pulse Ug, opens the main switching element 6 zhayuschy discharge the storage capacitor through the primary winding 5 of the transducer. The capacitor discharge k, like its charge, is oscillatory in nature and lasts for a time close to the charge time of capacitor 4. Since both windings 3 and 5 are turned on according to the discharge current of capacitor i causes 3 cores a magnetic field of the same direction. This is the way energy is supplied to the converter. in time with its oscillations, increasing them, and on the winding of the transducer, a krsinusoidal impulse of the same direction is induced. . At the end of the impulse, the switching element 6 is turned off, and the capacitor i is charged oppositely polarity relative to the power source 1. When the switching element 2 is reopened, the current pulse Jg and the voltage Us are increased, respectively, the process of capacitor charge, is additionally increased by the amplitude of oscillations of the converter. The increase in amplitude oscillations. Research institutes with alternating the charge charge of the capacitor through the windings 3 and 5 of the converter occurs until equality between the added and consumed energy at the same time is established. After the operation of the block of the pulse frequency 7 and the control unit of the switching elements 8 stop working the control pulses Uif and and both of the switching elements remain open and the oscillations of the converter gradually fade out. When the next pulse is generated, all processes are repeated. Possible operation mode of the device when, when generating acoustic pulses, the opening of switching elements occurs not with the frequency of acoustic oscillations, but with a lower one, but a multiple of this frequency. The present invention improves the performance and effects of cleaning the heat units from deposits by increasing the excitation efficiency of the magnetostrictive transducers in amplitude by 3 and in intensity by 10 times in comparison with the known devices.

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Claims (1)

ULTRASONIC DEVICE FOR CLEANING HEAT UNITS FROM DEPOSITS, including a power source, a pulse repetition rate unit and a storage capacitor, to the plates of which are connected through the power circuit of a switching element a magnetostrictive converter excitation coil, which is connected with the fact that in order to increase the productivity and cleaning efficiency, it is equipped with an additional field winding located on the magnetostrictive transducer and switched on in accordance with the first field winding a switching element, and a control unit for switching elements, the additional field winding being connected to the plates of the storage capacitor in series through the power circuit of the additional switching element and the power source, and the output of the pulse repetition rate unit is connected to the input of the switching unit control unit, the outputs of which ζ respectively connected to the control * circuits of the switching elements. *> 1022750 2