SU1480085A1 - Ultrasonic generator - Google Patents

Abstract

The invention relates to ultrasound technology. The purpose of the invention is to increase reliability. Ultrasonic g-r contains power supply 1, source 2 bias, magnetostrictive transducer / ICP / 3, diodes 4 and 5, transistors 6 and 7, bias sources 8 and 9, current switches 10 and 11, transformer 12, driving r-13 , threshold three-port 14 and two-input el-OR 15. 15. When the transistor 6 is disconnected, ICP 3 is applied to the difference in voltage of sources 2 and 1. Source 1 has a three-terminal breakdown voltage 14, the output of which is a single level signal and OR 15, forcibly opens the transistor 7 and causes a reset accumulated in the source 1 of the energy in the ICP 3 through the open transistors 6 and 7. The current of the ICP 3, the increase, passes the level of the constant component and, as soon as the three-terminal circuit 14 recovers its locked state, the pulse at its output ends. In the absence of control pulses at the output of switch 11, source 1 is in stabilization mode at the level of breakdown of three-port 14, and its excess energy enters SME 3. THIS REDUCES DANGER OF BREAKDOWN EL-TOV AND INCREASES RELIABILITY OF G-RA. 2 IL.

Description

four

00

oo ate

sources 2 and 1. Source 1 has a three-pole breakdown voltage 14, the output of which is a single level signal and, passed through OR 15, forcibly opens transistor 7 and causes the energy accumulated in source 1 in the ICP 3 to discharge through the open transistors 6 and 7. The current ICP 3, increase, pass the level of the constant component, and as soon as

The invention relates to ultrasound technology and can be used in power generators for ultrasonic magnetostrictive emitters.

The aim of the invention is to increase reliability.

Fig, 1 shows the structural scheme of the ultrasonic generator; Fig 2A-n - diagrams of his work.

The ultrasonic generator (Fig. 1) contains a power source 1, a bias source 2, a magnetostrictive transducer (MP) 3, the first and second diodes 4, 5, the first and second transistors 6, 7, the first 8 and second 9 bias sources, the first a current switch 10 with an inverting output, a second current switch 11, a transformer 12, a master oscillator 13, a three-terminal threshold 14, a two-input element OR 15, a transformer 12 contains a primary winding 16, the first and second secondary windings 17, 18; master oscillator 53 (FIG. 1) contains a power setting device 19, a self-oscillating timer 20 with continuous and pulse outputs, a comparator 21, And 22, 23 elements, a counting trigger 24 ..

Ultrasonic generator works as follows.

The initial state of the ultrasonic generator corresponds to the time interval (t19t2) in Fig. 2 and reflects the mode of normal operation. The voltage at the output of timer 20 has a sawtooth shape (Fig. 2a) and is compared with the level of the output voltage of the power setting device 19 (Fig. 2b).

to tripolar 14 will restore its locked state, the pulse at its output ends. In the absence of control pulses at the output of switch 11, source 1 is in stabilization mode at the level of a three-pole 14 breakdown, and its excess energy enters SME 3. This reduces the danger of electrical breakdowns and increases the reliability of Mr. 2 ill.

0

five

0

five

0

five

0

on the comparator 21. The result of the comparison is depicted in FIG. In turn, the voltage at the pulse output of timer 20 has a rectangular shape (Figure 2b), the negative triggering of which triggers the counting trigger 24. The output signal of the counting trigger 24 is depicted in Figure 2d. As a result of the logical multiplication of the signals at the outputs of the comparator 21 and the counting trigger 24, the elements 22 and 23 form square pulses (FIGS. 2e and 2g) whose durations tK change as the signal at the output of the power setting device 19 changes. The transformer 12 combines the output signals elements 22 and 23, producing a corresponding signal of different polarity with symmetric pulses shown in fig.2z. The first and second comparators 10, 11 perform a logical multiplication of the antiphase signals of the transformer 12 by constant levels of the signals of the first and second displacement sources 8, 9, with the first switch 10 also inverting its output signal. As a result, the signal at the output of the first current switch 10 has the form shown in Fig. 2i, and the signal at the output of the second switch looks like the one shown in Fig. 2k. The first transistor 6 is in the closed state for most of the period and is open for time tn, and the second transistor 7 is open and closed for time tn.

The logic of the first and second transistors 6, 7 in the initial state consists of four intervals.

As a result of their switching to the magnetostriction converter (MP) 3, the voltage determined by the signal in FIG. 2d is applied and current flows in accordance with FIG. 2 In the first interval, the first and second transistors 65 7 are open (zero levels in FIG. 2i and 2k), K MP 3 is applied the voltage difference between the source 2 of the bias and the source 1 of the power supply (level 2-1 in fig. 2d) under which the current decreases, becoming less than the constant component i.0. The current flows through the circuit MP 3 - the second diode 5 - the power source - the first diode 4 - the source 2 of the magnetization and the MP 3. On the second interval, the first transistor 6 is closed and the second transistor 7 is open (unit level nafig, 2i and zero -% ff) 2k) To MP 3 the voltage of the source 2 of the magnetization is applied (level 2 in FIG. 2l. Under its action, the current begins to increase s and rises to the level of the constant component rc (figure 2m). At the same time the current flows through the circuit MP 3 - the second diode 5 - the first transistor 6 - the source 2 of the bias and the MP 3. In the third interval, both transistor 6, 7 (unit levels on, figs 2i and 2k) n K MP 3 the sum of the voltages of the power source 1 and the power source 2 of the paramagnetic is applied (level 2 + 1 in fig.2l). The current MP 3 rises above the level of 10 (fig. 2m) s flow through the circuit (figure 1): MP 3 - second transistor 7 - source 1 - first transistor 6 - source 2 and MP 3. The fourth interval corresponds to the second with the only difference that the current tends to a constant component, decreasing. In the initial state, the source 1 and the source 2 exchange their energies 5 being in the dynamic equal vesii. The source voltage 1, in particular, does not exceed its operating value. Threshold three-pole 14 does not transmit its information signal output (fcg.2n) and the two-input borrowing OR does not accept participation in the work. Long-term opening (or closure) of the first transistor 5 (or the second transistor 7) can lead to disruption of the dynamic equilibrium between sources 1 and 25 lhrh on this

ten

15

20

25

thirty

five

0

five

0

five

output of one of them occurs overvoltage. The most realistic long-term opening of the second transistor 7 (FIG. 2k for t 7 t2). There are at least two reasons leading to this - the failure of the second current switch 11 and the mismatch of the turn-off times of the first and second transistors 6, 7. The consequence of loss of control pulses at the output of the second transistor 7 is the ability to breakdown the first 6 and second 7 transistors and the possibility of the impact of a working tool (not shown) attached to the MP 3. The compensation system for the turn-off times of the first and second transistors 6, 7 is designed to prevent the process of pumping energy from point 1 to source 2 with the subsequent increase of the constant component 10 in MP 3. It delays the appearance of the control pulse at the output of the second current switch 1, equalizing the duration of the control pulses of the first and second transistors 6, 7

This delay is formed by comparing two parameters: a constant voltage at the output of source 2 and a value of current i0 MP 3. The increase in current 10 in transients affects the formation of this delay and can permanently eliminate control pulses at the output of the second current switch 11. Let (Fig. 2k) from the moment of time t the control pulses from the output of the second current switch 11 completely disappear, and the first switch 10 continues to operate. Skipping the first pulse will lead to the continuation of the current increase to the level of 1 ", and the next opening of the first transistor 6 following it will cause the current to drop to zero, i.e. switch to intermittent current mode. During the fall of the current, the source 2 through the first and second diodes 4, 5 (FIG.) Will give the source 1 an additional charge that it has nowhere to spend. With the closure of the first transistor 6, the current rise to the level 10 will begin again. 1 and 2-1).

At time t3, the voltage at the output of source 1 reaches the breakdown value of the threshold three-port network (Fig 2l, level 1) K MP 3 when the first transistor opens

6, a voltage difference of source 2 and source 1 is applied. The latter has a breakdown voltage of a threshold three-terminal 14, at the output of which a single level signal (FIG. 2n), which, having passed a two-input element OR 15, forcibly opens the second transistor

7 will cause the discharge of the energy stored in the source 1 in the MP 3 through the open first and second transistors 6, 7, the current MP 3, increase, pass level 10 and, as soon as the threshold three-pole 14 recovers its locked state, the pulse at its output will end at the absence of control pulses at the output of the second current switch 11 (the third pulse in Fig. 2k), source 1 will be in the stabilization mode at the level of the breakdown of the threshold three-port 14, and its excess energy will flow to MP 3

As a result, the danger of breakdown of elements is reduced, and it increases reliably.

Claims (1)

The invention is an ultrasonic generator comprising a master oscillator, a transformer consisting of a primary winding and a first and second secondary circuit. five the current, the power source, the dual single-ended amplifier, which is made according to the bridge circuit, two opposite arms of which are made on the first and second transistors respectively, and the other two arms on the first and second diodes, respectively, the first offset source, which through the first current switch with the inverting output is connected to the control input of the first transistor, the second bias source, the output of which is connected to the input of the second switch, while the power source is connected to one of the bridge diagonals, th diagonal of which are connected in series and connected to a source of bias 0 magnetostrictive transducer, the primary winding of the transformer is connected to the output of the master oscillator, the first secondary winding of the transformer is connected to the control 5 input of the first switch, second The secondary winding of the transformer is connected to the control input of the second current switch, characterized in that, in order to improve reliability, a threshold three-port network is inserted, which is connected parallel to the power source, and a two-input element OR, the first input of which is connected to the output of the threshold three-terminal network, the second two-input input - the OR element is connected to the output of the second current switch, and the output of the two-input element OR is connected to the control input of the second transistor. five ft-15,17 eight