RU2535763C1 - Electric impulse de-icing device - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: electric impulse de-icing device is related to impulse devices and may be used for mechanic de-icing of metal coating of vehicles such as planes, helicopters, aerofoil boats and vessels. It comprises electromagnetic induction coils, a control pulse distributer and an ice detector. The electromagnetic induction coils are coupled through thyristors in parallel to a storage capacitor connected to a charger. The control pulse distributer comprises in-series clock generator, a pulse counter and a decoder. The clock generator is frequency controlled; it includes the master clock, a three-digit binary counter, a multiplexor, and three comparators. The decoder outputs are connected through pulse amplifiers to control electrodes of the thyristors. The ice detector output is coupled to the controlled input of the clock generator. The device ensures partial load modes of force impact during pulse treatment of the de-iced coating.

EFFECT: reducing probability of coatings damage, reducing consumed power of the device and increasing its service life.

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Description

The invention relates to anti-icing impulse devices and can be used for mechanical removal of ice from metal skins of vehicles, such as aircraft, helicopters, ekranoplanes and ships.

Known anti-icing device (Patent RU 2112708, IPC B64D 15/16, 06/10/1998) containing a charging element, a storage capacitor, coils, thyristors, a control unit and a voltage pulse shaper.

The disadvantage of this device is that regardless of the degree of icing of the casing, the device creates impulses of power action of an unchanged maximum value. In this case, residual deformation occurs in the casing, which, on the one hand, leads to its damage, and on the other hand, to a decrease in the efficiency of the anti-icing device.

Closest to the proposed device is an electric pulse device for removing ice from the wings of an airplane (Patent US 5129598, IPC B64D 15/00, B64D 15/16, 07/14/1992), containing inductors located inside the wings near the metal skin, a battery charger with storage a capacitor, to which inductors are connected in parallel through the thyristors, and a distribution block of pulses controlling the thyristors.

The disadvantage of the device also lies in the fact that the amplitude of the pulses of force on the wing skin does not change depending on the degree of icing and in many cases is excessive. This leads to damage to the casing, an increase in the gaps between the inductors and the casing, and, as a result, a decrease in the efficiency of the device.

The proposed device allows you to change the amplitude of the pulses of force on the surface cleaned from ice, depending on the degree of icing, providing a sparing mode of operation.

Figure 1 presents a functional diagram of an electric pulse anti-icing device, and figure 2 is a timing diagram of the voltage across the storage capacitor - u _s and discharge current pulses - i _bit in various modes of operation of the device.

The device comprises electromagnetic inductors 2 mounted near metal sheathing 1, connected through thyristors 3 in parallel with a storage capacitor 4 connected to a charging device 5, and a control pulse distributor including a clock generator 6 connected in series, a pulse counter 7, and a decoder 8. The outputs of the decoder 8 through pulse amplifiers 9 are connected to the control electrodes of the thyristors 3. The device is equipped with a sensor 10 icing of the cleaned surface 1, and the clock generator 6 olnen controlled frequency, wherein the output of the sensor 10 is connected to the control input of oscillator 11 June.

The generator 6 contains a master generator 12 connected to the input of a three-digit binary counter 13, the outputs of which are connected to the information inputs of the multiplexer 14, the output of which is connected to the output 15 of the generator 6, and three comparators 16, 17, 18. The common input of the comparators 16, 17, 18 connected to the input 11 of the generator 6, and the outputs to the address inputs of the multiplexer 14. The unused information inputs of the multiplexer 14 are connected to ground (not shown in figure 1).

Electro-pulse anti-icing device operates as follows.

With the formation of ice on the metal casing 1, the operator includes an anti-icing device. In this case, the charger 5 starts charging the capacitor 4, and a voltage appears at the output of the sensor 10, the magnitude of which is proportional to the thickness of the ice. At the same time, a generator 12 starts operating, starting the counter 13, at the first (upper) output of which the pulse frequency will be two times higher than at the second (average), and four times higher than at the third (lower) output. With a small thickness of ice, the voltage supplied from the sensor 10 to the input 11 of the generator 6 is small and only the comparator 16 is triggered from the three comparators 16, 17, 18. As a result, a code combination 100 is generated at the outputs of the comparators 16, 17, 18, which translates the multiplexer 14 to a state in which pulses arriving at its output pass to its input “01” from the first output of counter 13, that is, pulses with the highest frequency. The pulse repetition period is chosen equal to a quarter of the time of the full charge of the capacitor 4 (3T / 4 = 0.75T). Under the influence of these pulses, the counter 7 is controlled, which controls the decoder 8, which, at a specified frequency, opens the thyristors 3, discharging the capacitor 4 to the inductors 2, removing ice from the casing 1. In this mode, the capacitor 4 manages to charge up to a value of approximately half the maximum value of the voltage of the capacitor with unlimited time of its charge. The amplitude of the discharge current pulse is also equal to half of the maximum amplitude. Thus, the treatment of the casing with a small thickness of ice is carried out by low-power pulses of force, but at a high repetition rate. The diagrams corresponding to this case are shown in FIG. 2c).

With an increase in the thickness of ice on the casing 1, the output voltage of the sensor 10 increases. In addition to the comparator 16, the comparator 17 is activated and a code combination 110 is applied to the address inputs of the multiplexer 14, which transfers the multiplexer 14 to a state in which pulses transmitted to its input pass to its output "03" from the second output of the counter 13. In this case, the pulse repetition period will be equal to half the time of the full charge of the capacitor 4 (3T / 2 = 1.5T). During this time, the capacitor 4 will have time to charge up to a value approximately equal to 77% of the possible maximum value. The amplitude of the discharge current pulse will also be this value from the maximum possible. As a result, the processing of the skin will be carried out by more powerful pulses of force, but with a frequency two times lower than the previous case. On figb) shows the corresponding diagrams.

With a further increase in the ice thickness, in addition to the comparators 16, 17, the comparator 18 is activated, a combination of 111 is applied to the address inputs of the multiplexer 14 and pulses from the third output of the counter 13 pass to its output. Their repetition period is equal to the time of the full charge of the capacitor 4 (3T). During this time, the capacitor 4 will be charged to its maximum value, and when it is discharged, a current pulse with a maximum amplitude will be formed. In this case, the casing will be exposed to the most powerful force pulses, but their repetition rate will be minimal. Timing diagrams for this mode are shown in figa).

The generator 6 can also be performed using widespread voltage to frequency converters, however, in this case they have some redundancy, complicating their use.

To obtain other ratios between the periods of repetition of clock pulses and the magnitude of the pulses of power actions in various modes of operation of the device can be applied to more complex circuits of the counter 13 and the multiplexer 14.

In the absence of the sensor 10, the operation mode of the device can also be set using an additionally entered switch that feeds the corresponding code combinations to the address inputs of the multiplexer 14.

Thus, the proposed device provides gentle modes of processing by pulses of the force impact of the skin being cleaned from ice. The operation mode of the device is determined by the degree of icing of the object. As a result, the likelihood of damage to the casing is reduced, the efficiency of the anti-icing device is increased, its service life is increased and the power consumption is reduced.

Claims (2)

1. Electropulse de-icing device containing electromagnetic inductors mounted near metal sheathing, connected through thyristors in parallel to a storage capacitor connected to a charging device, and a control pulse distributor including a clock generator, a pulse counter and a decoder connected in series, the outputs of which are connected via pulse amplifiers to the control electrodes of the thyristors, characterized in that it is equipped with a sensor for icing cleaning surface, and the clock generator is made controlled by frequency, and the output of the icing sensor is connected to the control input of the clock generator. 2. The device according to claim 1, characterized in that the frequency-controlled clock generator includes a master oscillator connected to the input of a three-digit binary counter, the outputs of which are connected to the information inputs of the multiplexer, the output of which is connected to the output of the clock generator, and three comparators, a common input which is connected to the control input of the clock generator, and the outputs are with the address inputs of the multiplexer.

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