RU2728914C1 - Device for active vibration protection of electronic equipment - Google Patents

Abstract

FIELD: printing equipment.

SUBSTANCE: invention relates to devices for protection of printed circuit boards from vibration action. Device of active vibration protection of electronic equipment consists of in-series electrically connected converter of mechanical energy into electric, charge amplifier, phase shifter and converter of electric energy into mechanical, the last of which is kinematically connected to plate, metal case. Plate is intended for attachment of electronic equipment and is made in the form of a printed-circuit board. Metal case is made in the form of a hollow rectangular parallelepiped, in which the elastic plate is installed so that it forms one of its faces. In the metal housing there is a converter of electric energy into mechanical one, which one side is fixed on the inner surface of the plate, and the other side is fixed on the inner surface of the base of the metal housing.

EFFECT: simplified design, which increases speed of operation, as well as high reliability of structure and noise immunity.

1 cl, 2 dwg

Description

The invention relates to the field of instrumentation, in particular to devices for protecting printed circuit boards from vibration.

An active vibration damping device is known (RF patent No. 2416551 priority dated 01/03/2006, "Active vibration damping device experienced by a fragile element of moving equipment with automatic power supply" authors Blanchard Laurent, Dupuis Jean, IPC: F16F 15/00, B64G 1/38, published on April 20, 2011, Bulletin No. 11). The invention relates to a vibration damping device for movable equipment, equipment with such a device and the use of this device in the space field. The vibration damping device comprises a structure to which the first element and the second fragile element are connected, protected from the mentioned vibrations, the first piezoelectric conversion means included between the structure and the first element and installed to convert the mechanical vibration energy of the structure into electrical energy, one sensor connected to the structure and installed to provide measurement signals characteristic of vibrations experienced by said equipment, control means electrically powered by said electrical energy and installed to obtain from each measurement signal a single displacement amplitude. The amplitude of displacement is designed to compensate for the mentioned vibrations experienced by the structure, as well as to issue control signals characteristic of each defined amplitude. Second piezoelectric conversion means of the vibration damping device are included between the structure and the second element and are installed to convert said control signals into movement (s) so as to partially damp vibrations for the second element experienced by said equipment.

The disadvantages of the known device are the complex design, the ineffectiveness of protection against high levels of vibration due to the use of piezoelectric protection.

Known device for active vibration protection of electronic equipment (Lysenko AV thesis "INFORMATION-MEASURING SYSTEM OF CONTROL OF ACTIVE VIBRATION PROTECTION OF RADIO-ELECTRONIC DEVICES", Penza 2014, pp. 80-100 Fig. 3.3, Fig. 3.5, Fig. 4.10), containing sequentially connected primary converter of the first active shock absorber (converter of mechanical energy into electrical energy), a control unit, and four active shock absorbers (converter of electrical energy into mechanical energy). A platform is installed on the active shock absorbers, the outer surface of which is intended for fastening radio electronic devices, and the inner surface of the control unit is attached. The signal from the vibration source goes to the active dampers. With the help of the primary transducer of the first shock absorber, vibration readings are taken and transferred to a functional transducer (control unit). In it, the signal is amplified to the required level using an amplifier (charge amplifier) and converted into digital for further processing. The digital signal is fed to the signal difference synthesizer, in which four signals are formed according to the transformation law. The generator, according to the developed algorithm, shifts the phase of each channel by the required angle (phase shifter). After digital-to-analog conversions, the signals, passing through the corresponding amplifiers, are fed to the active shock absorbers and, thanks to the summation of the signals, a signal of the required level is output to the vibration protection object. The first active shock absorber (vibration shock absorber) with a primary transducer consists of an inductance coil attached to a rod in a constant magnetic field, which is used to measure the value of the amplitude of the external vibration effect entering the shock absorber. The stem is fixed on the upper and lower suspensions, which act as membranes for decoupling mechanical vibrations affecting the stem and permanent magnets. The signal from the measuring inductance coil, the amplitude of which changes in antiphase with the external vibration, enters the functional converter, in which the signal is amplified in amplitude, the phase mismatch is introduced, and digital-to-analog and analog-to-digital conversions take place. From the output of the processing unit, the signal is directed to a master inductor located on the same rod as the measuring coil, but in the magnetic field of the second permanent magnet. As a result, a vibration action is excited that is phase-shifted relative to the input action. The superposition of two vibration signals on one rod provides a compensating effect that dampens the external vibration impact and reduces the vibration amplitude of the REU as a whole. The effect of vibration damping at resonant frequencies is especially significant. This device was chosen as the closest analogue, which is an electromechanical active vibration protection system. The electromechanical system is designed to protect against infra-low frequencies. It has the advantages of electro-hydraulic systems. The frequency range of action of electromechanical systems is much narrower, and the system will be operational only up to frequencies not exceeding 5-10 Hz. A distinctive feature of electromechanical systems is the implementation of the power drive in the form of a tracking system (electrical), which acts on the actuator.

The disadvantage of this device is its complex execution scheme.

A technical problem is the creation of an effective device for active vibration protection of electronic equipment.

The technical results to be achieved by the invention are to simplify the design, which entails an increase in protection against vibrations, an increase in the response speed, as well as an increase in the reliability of the structure and noise immunity.

These technical results are achieved by the fact that in a device for active vibration protection of electronic equipment, which contains a series-electrically connected mechanical-to-electrical converter, a charge amplifier, a phase shifter and an electrical-to-mechanical converter, the latter of which is kinematically connected to a platform that is designed for fixing electronic equipment with a new is that the platform is made in the form of an elastic plate, a metal body made in the form of a hollow rectangular parallelepiped is additionally introduced, in which an elastic plate is installed in such a way that it forms one of its faces, while a converter of electrical energy into mechanical is installed in the metal body , one side of which is fixed on the inner surface of the platform, and the other side on the inner surface of the base of the metal body.

The increase in reliability is due to the elimination of the piezoelectric element (the converter of electrical energy into mechanical energy is a passive device), which also increases noise immunity, and also provides the ability to compensate for higher levels of vibration.

The increase in performance is achieved due to the fact that the device for active vibration protection of electronic equipment is a device that is powered from an external power source, and, therefore, no time is spent on reaching the required value of the supply voltage, and the performance is also increased due to the fact that no additional monitoring devices are required ...

The use of an elastic plate as a platform makes it possible to exclude the use of additional elastic elements based on vibration isolators (shock absorbers), which simplifies the implementation scheme and further increases the protection against vibration.

The concept of placing the protection system directly on an elastic plate from the composition of small-sized on-board equipment makes it possible to simplify the protection implementation scheme.

FIG. 1 shows a variant of a device for active vibration protection of electronic devices located on a printed circuit board. FIG. 2 - axial section of the structure of the converter of electrical energy into mechanical.

The device for active vibration protection of electronic equipment (Fig. 1) contains an elastic plate 1, a converter 2 of mechanical energy into electrical energy, a converter 3 of electrical energy into mechanical, metal body 4 and a charge amplifier 5, a phase shifter 6.

The elastic plate 1 is made in the form of a substrate 1 of a printed circuit board, on which ERIs are located (not shown in Fig. 1).

The converter 2 of mechanical energy into electrical energy can be made in the form of a piezoelectric accelerometer 2 and installed on the substrate 1.

The charge amplifier 5 and the phase shifter 6 can be implemented on operational amplifiers and are designed to amplify and change the phase of the input signal coming from the piezoelectric accelerometer 2. In this case, the converter 2 of mechanical energy into electrical energy, charge amplifier 5, phase shifter 6 and converter 3 of electrical energy into mechanical are electrically connected in series.

The metal body 4 is made in the form of a hollow rectangular parallelepiped, in which the substrate 1 is installed in such a way that it forms one of its faces.

In the metal case 4, a converter 3 of electrical energy into mechanical is installed, one side of which is mounted on the inner surface of the substrate 1, and the other side on the inner surface of the base of the metal body 4, while the converter 3 of electrical energy into mechanical energy is kinematically connected to the substrate 1.

The converter 3 of electrical energy into mechanical (Fig. 2) contains the first 7, the second 8 and the third 9 inductance coils, housing 10, cover 11, sleeve 12, rod 13, washer 16.

The body 10 is made in the form of a ring, on one end of which the cover 11 is fixed by means of screws 14. The other end of the body 10 is fixed on the inner surface of the base of the metal body 4 (not shown in Fig. 2). In the opening of the housing 10 (ring 10), a rod 13 is installed with the possibility of axial movement. One end of the rod 13 is fixed on the substrate 1 of the printed circuit board (not shown in Fig. 2), on the other end of the rod 13, the washer 16 is fixed with a screw 17. A recess is made in the ring 10 on the side of the substrate 1 of the printed circuit board, in which the first inductor 7 is fixed, a protrusion is made on the inner surface of the first inductor 7. A sleeve 12 is installed between the rod 13 and the ring 10, on which the protrusion of the first inductor 7 is fixed. In the gaps formed by the surfaces of the rod 13, the sleeve 12, the protrusion of the first inductor 7 and the inner surface of the ring 10, respectively, the second 8 and third 9 inductance coils are installed with the possibility of axial movement, while the second 6 and third 7 inductors are kinematically connected to the rod 13 ...

The cover 11 contains contacts 15 for electrical connection of the first 7, second 8 and third 9 inductors with a phase shifter 6 (not shown in Fig. 2).

The piezoelectric accelerometer 2 is an active sensor that generates an electrical signal proportional to the mechanical vibrations of the PCB substrate 1.

Each coil 7 (8, 9) inductance contains a cylindrical frame made of non-magnetic material, on which the wire is wound.

The device for active vibration protection of electronic equipment works as follows.

The external power is pre-supplied to the operational amplifiers of the charge amplifier 5 and the phase shifter 6.

When vibrations of the substrate 1 of the printed circuit board (hereinafter referred to as the printed circuit board 1) occur, the piezoelectric accelerometer 2 generates an electrical signal proportional to the mechanical vibrations of the printed circuit board 1. Next, the specified electrical signal through the charge amplifier 5 is amplified to the required level and fed to the phase shifter 6 to change the phase of the input signal ... From the phase shifter 6, the electrical signal is fed to the moving inductors 8 and 9.

The wires of the inductors 8 and 9 through the cover 11 are brought out to the contacts 15, through which voltage is supplied to drive the rod 13 in motion. Power is supplied through the phase shifter 6 to the inductance coil 7, by means of which a constant magnetic field is created in the gaps formed by the surfaces of the rod 13, the sleeve 12, the protrusion of the first inductor 7 and the inner surface of the ring 10.

The electrical signal from the phase shifter 6 is fed to the moving inductors 8 and 9.

Inductors 8 and 9, moving in a constant magnetic field created by the inductor 7, convert an electrical signal proportional to a mechanical signal to compensate for the vibration level of the substrate 1. Coils 8 and 9, kinematically interacting with the rod 13, move it to the vibration amplitude, but in the opposite direction. Compensation is achieved by the fact that the signal from the piezoelectric accelerometer 2 and the signal applied to the moving coils of the electromagnet are the same in amplitude and different in phase.

Claims (2)

1. A device for active vibration protection of electronic equipment, containing a series of electrically connected mechanical-to-electrical energy converter, a charge amplifier, a phase shifter and an electrical energy-to-mechanical converter, the latter of which is kinematically connected to a plate, which is intended for fastening electronic equipment, characterized in that the plate is made in the form of a printed circuit board, a metal case is additionally introduced, made in the form of a hollow rectangular parallelepiped, in which an elastic plate is installed in such a way that it forms one of its faces, while an electrical energy to mechanical converter is installed in the metal case, one side of which is fixed on the inner surface of the plate, and the other side is on the inner surface of the base of the metal body. 2. The device for active vibration protection of electronic equipment according to claim 1, characterized in that the converter of electrical energy into mechanical energy is made in the form of an electrodynamic or piezoelectric converter.

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