A three-dimensional electronic system for steering gear based on rigid-flex printed circuit board

Abstract

The present invention relates to a three-dimensional electronic system for a steering gear based on a rigid-flexible printed circuit board, comprising four layers of printed circuit boards stacked from top to bottom; the top printed circuit board carries and installs a telemetry control unit of the steering gear, the middle printed circuit board carries and installs a low-power unit of the steering gear, the second-middle printed circuit board carries and installs a power drive unit of the steering gear, and the bottom printed circuit board carries and installs a power supply unit; the top printed circuit board and the middle printed circuit board are connected through a first interlayer flexible printed circuit board; the top printed circuit board and the second-middle printed circuit board are connected through a second interlayer flexible printed circuit board; the second-middle printed circuit board and the bottom printed circuit board are connected through a third interlayer flexible printed circuit board. The three-dimensional electronic system of the present invention adopts a rigid-flexible printed circuit board structure to replace the internal cable connection, and the three-dimensional layout after the flexible printed circuit board is bent makes the structure more compact, occupies less space, and has more optimized processability.

Description

Technical Field

[0001] The present invention relates to the technical field of steering gears, and in particular to a three-dimensional electronic system for steering gears based on a rigid-flex printed circuit board. Background Art

[0002] With the rapid development of aircraft and weapon systems, the demand for lightweight, miniaturized, and rapid prototyping designs has increased dramatically. Electric servos have irreplaceable advantages over pneumatic and hydraulic servos. However, electric servos have many electrical cables, high electromagnetic performance requirements, and many reliability links. For missile weapon systems, the more compact the structure of sensors and actuators and the smaller the size, the greater the effective killing ratio they can provide.

[0003] As a missile actuator, in the traditional design, the mechanical structure and electrical circuit equipment of the servo must be connected by cables to form a channel for data and energy transmission, which requires cable design and PCB welding and routing between circuit modules. When designing cables and PCB welding and routing, it is necessary to calculate the routing length, form routing, open wire welding, solder joint inspection, and silicone curing. The above design and operation not only increase the difficulty of servo design, increase the weight of weapons and equipment, and increase the space occupied by solder joint glue curing and screw fastening methods; but also there are many types of cables inside the servo, and the small space makes it difficult to operate, which is a big test for the operator's craftsmanship. In addition, the internal cable branches are complex, the plugs are prone to misoperation, and the production, transportation, installation, and protection of the cables are all key quality control nodes, which brings risks to the reliability control of the servo. Summary of the invention

[0004] In view of the above analysis, the present invention aims to provide a three-dimensional electronic system for a steering gear based on a rigid-flex printed circuit board, and solve the problems caused by internal cable connections in the steering gear electronic system.

[0005] The present invention discloses a three-dimensional electronic system for a steering gear based on a rigid-flex printed circuit board, comprising four layers of printed circuit boards stacked from top to bottom; the top layer of the printed circuit board carries and installs a telemetry control unit of the steering gear, the middle layer of the printed circuit board carries and installs a low-power unit of the steering gear, the second middle layer of the printed circuit board carries and installs a power drive unit of the steering gear, and the bottom layer of the printed circuit board carries and installs a power supply unit;

[0006] The top printed board and the middle printed board are connected through the first interlayer flexible printed board, which is used for control and sensor signal transmission between the telemetry control unit and the low power unit; the top printed board and the second interlayer flexible printed board are connected through the second interlayer flexible printed board, which is used for control signal transmission between the telemetry control unit and the power drive unit; the second interlayer flexible printed board and the bottom printed board are connected through the third interlayer flexible printed board, which is used for power supply distribution from the power supply unit to the power drive unit.

[0007] Furthermore, the top-layer printed circuit board is an integrated rigid printed circuit board, which is connected to one end of the first interlayer flexible printed circuit board through a first plug port; and is connected to one end of the second interlayer flexible printed circuit board through a second plug port; the telemetry control unit adopts a DSP+FPGA architecture, obtains the servo sensor signal from the first plug port and combines it with the external telemetry control signal to generate a servo control signal, and outputs the servo control signal to the power drive unit carried by the secondary middle layer printed circuit board through the second plug port.

[0008] Furthermore, the middle layer printed circuit board is a rigid-flexible integrated printed circuit board, and the rigid area of ​​the printed circuit board adopts a split layout, which is divided into a first middle layer rigid area, a second middle layer rigid area, a third middle layer rigid area and a fourth middle layer rigid area of ​​the same shape and 90° apart to form a circle; adjacent middle layer rigid areas are connected by four middle layer flexible printed circuit boards;

[0009] A low-power module is carried and mounted on each middle rigid zone for processing sensing information and electromechanical lock control information;

[0010] The middle-layer flexible printed circuit board connected between adjacent middle-layer rigid areas is used to form an information transmission area to transmit sensor information and electric mechanical lock control information between the four middle-layer rigid areas.

[0011] Furthermore, the other end of the first interlayer flexible printed circuit board forms a rigid-flexible integrated structure with one of the four middle-layer rigid areas; the sensing information processed by the low-power module on each middle-layer rigid area is transmitted to the telemetry control unit of the top-layer printed circuit board through the first interlayer flexible printed circuit board and the middle-layer flexible printed circuit board; the electric mechanical lock control logic generated by the telemetry control unit is output to each low-power module.

[0012] Furthermore, each middle-layer rigid zone is also connected to the angle, temperature and current sensors via the flexible printed circuit board ZC which adopts a rigid-flexible integrated structure therewith; and is also connected to the electric mechanical lock via the flexible printed circuit board ZS which adopts a rigid-flexible integrated structure therewith.

[0013] Further, the sub-middle layer printed circuit board includes four sub-middle layer units with the same shape and structure;

[0014] Each secondary middle layer unit includes a rigid board, a first middle layer flexible board, a second middle layer flexible board, and a transfer board; the rigid board, the first middle layer flexible board, and the second middle layer flexible board adopt a rigid-flexible integrated structure, and the rigid board and the transfer board are interconnected by a 90-degree bent pin plug-in method;

[0015] The rigid plate is used to carry and install the power drive module;

[0016] The first inter-middle layer flexible board and the second inter-middle layer flexible board are used to connect adjacent sub-middle layer units through the plug-in ports to form a control information transmission area;

[0017] The adapter board is used to transfer the driving power output by the power supply unit to the rigid board to power the power driving module, transfer the motor driving signal output by the power driving module to the motor, and transfer the motor Hall signal to the power driving module.

[0018] Furthermore, the other end of the second interlayer flexible printed circuit board forms a rigid-flexible integrated structure with one of the four sub-middle layer units; through the second interlayer flexible printed circuit board and the first inter-middle layer flexible board and the second inter-middle layer flexible board of each sub-middle layer unit; the motor control command output by the telemetry control unit is output to the power drive module carried by each sub-middle layer unit.

[0019] Furthermore, the third interlayer flexible printed circuit boards include four pieces, one end of each of which is connected to a adapter board of a secondary middle layer unit to form a rigid-flexible integrated structure, and the other end is connected to the bottom layer printed circuit board through a plug-in port, so as to provide high and low voltage power supply voltages to each power driving module.

[0020] Furthermore, the bottom printed circuit board is an integrated rigid printed circuit board, which carries and installs an external power supply interface and four power supply circuits corresponding to the four secondary middle layer units; it is used to distribute the external 28V power supply circuit to the four power supply circuits; each power supply circuit performs two-way EMI filtering on the external 28V to form a controller 28V power supply and a driver 28V power supply, wherein the driver 28V power supply outputs a high-voltage power supply after energy storage in the energy storage module.

[0021] Furthermore, the third interlayer flexible printed circuit board connects the controller 28V power supply, the driver 28V power supply and the high-voltage power supply to the sub-middle layer unit in the corresponding sub-middle layer printed circuit board; the controller 28V power supply is transferred to the top layer printed circuit board through the second interlayer flexible printed circuit board connected to the sub-middle layer printed circuit board to power the telemetry control unit; after the secondary power supply module of the telemetry control unit performs voltage conversion, it is output to the middle layer printed circuit board through the first interlayer flexible printed circuit board to provide driving voltage to the MOS tube of the electric mechanical lock driving circuit.

[0022] The beneficial effects of the present invention are as follows:

[0023] The present invention adopts the planar design of the rigid-flexible printed circuit board to replace the internal cable connection, and the three-dimensional layout after the flexible printed circuit board is bent makes the structure more compact, occupies less space, and has more optimized processability;

[0024] The three-dimensional design of rigid-flex printed circuit boards saves assembly time, omits the process of electrical welding and on-site inspection, increases the design assurance ratio of product quality, and weakens the assurance of process; it saves personnel costs, ensures quality, and reduces the probability of misoperation.

[0025] It is conducive to mass production, has high efficiency and high yield rate, and ensures rapid design and rapid assembly, providing strong support for the modernization of equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0027] Figure 1 Schematic diagram of the structure of a three-dimensional electronic system for a steering gear in an embodiment of the present invention;

[0028] Figure 2 Schematic diagram of the top printed circuit board structure in an embodiment of the present invention;

[0029] Figure 3 Schematic diagram of the structure of the middle printed circuit board in the embodiment of the present invention;

[0030] Figure 4 Schematic diagram of the installation structure of the middle printed circuit board in the embodiment of the present invention;

[0031] Figure 5 Schematic diagram of the structure of the secondary middle layer printed circuit board in the embodiment of the present invention;

[0032] Figure 6 is a schematic diagram of the installation structure of the secondary middle layer unit in an embodiment of the present invention;

[0033] Figure 7 Schematic diagram of the structure of the bottom printed board in the embodiment of the present invention;

[0034] Figure 8 It is an installation diagram of a printed circuit board in a three-dimensional electronic system in an embodiment of the present invention;

[0035] Fig. 9 The figure is a schematic diagram of the composition and connection of specific circuit modules of the electronic system in the embodiment of the present invention.

[0036] Figure numerals: 110-top printed circuit board, 120-middle printed circuit board, 130-second middle printed circuit board, 140-bottom printed circuit board; 301-middle rigid area, 302-middle flexible area, 303-first inter-layer flexible printed circuit board, 304-first plug-in port, 305-flexible printed circuit board ZC, 306-flexible printed circuit board ZS; 401-rigid board, 402-first inter-middle flexible board, 403-second inter-middle flexible board, 404-second inter-layer flexible printed circuit board, 405-second plug-in port, 406-second middle unit plug-in port, 407-adapter board, 408-motor and Hall signal adapter flexible printed circuit board, 409-third inter-middle flexible board, 410-power supply circuit plug-in port. DETAILED DESCRIPTION

[0037] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used to illustrate the principles of the present invention together with the embodiments of the present invention.

[0038] This embodiment discloses a three-dimensional electronic system for a steering gear based on a rigid-flex printed circuit board, such as Figure 1 As shown, it includes four layers of printed circuit boards stacked from top to bottom; the top printed circuit board carries and installs the telemetry control unit of the steering gear, the middle printed circuit board carries and installs the low-power unit of the steering gear, the second middle printed circuit board carries and installs the power drive unit of the steering gear, and the bottom printed circuit board carries and installs the power supply unit;

[0039] The top printed board and the middle printed board are connected through the first interlayer flexible printed board, which is used for control and sensor signal transmission between the telemetry control unit and the low power unit; the top printed board and the second interlayer flexible printed board are connected through the second interlayer flexible printed board, which is used for control signal transmission between the telemetry control unit and the power drive unit; the second interlayer flexible printed board and the bottom printed board are connected through the third interlayer flexible printed board, which is used for power supply distribution from the power supply unit to the power drive unit.

[0040] Specifically, Figure 2 As shown, the top printed circuit board is an integrated rigid printed circuit board, which is connected to one end of the first interlayer flexible printed circuit board through a first plug port; and is connected to one end of the second interlayer flexible printed circuit board through a second plug port; the telemetry control unit adopts a DSP+FPGA architecture, obtains the servo sensor signal from the first plug port and combines it with the external telemetry control signal to generate a servo control signal, and outputs the servo control signal to the power drive unit carried by the secondary middle layer printed circuit board through the second plug port.

[0041] Specifically, the telemetry control unit mainly includes an embedded digital processing module, an analog-to-digital converter, a high-speed communication module and a power supply module;

[0042] Among them, the embedded digital processing module adopts the DSP+FPGA architecture as the control core of the servo system, generates servo control signals including PWM&DIR according to the acquired servo sensor signals combined with the external telemetry control signals, and realizes the overall control of the servo movement. The "one-to-four" structure sampled in this embodiment, that is, one embedded digital processing module is used to control the movement of four servos. The volume of the servo electronic system is reduced.

[0043] Preferably, the DSP model in the embedded digital processing module is TMS320F28377D, and the FPGA is XC7S50 in a small package of the sparten-7 series.

[0044] High-speed communication modules include telemetry RS422 communication module and 1553B communication module;

[0045] Among them, the RS422 communication module realizes remote RS422 communication through the peripheral SCI interface and the RS422 transceiver chip MAX3491, and uses the chip ADUM1400 to isolate the bidirectional RS422 communication signal;

[0046] The steering gear control quantity and direction signal are used for isolation and voltage conversion of brushless motor control signals through the external PWM interface, photocoupler GH0631 and level conversion chip SN74LVC164245;

[0047] 1553B communication module, through the peripheral XINTF and low voltage 1553B chip BU64843 to achieve 1553B communication of the servo; and use isolation transformer B3226 to achieve signal isolation;

[0048] The analog-to-digital converter realizes analog quantity acquisition through the peripheral SPI and the analog-to-digital converter chip AD7606A, adopts the operational amplifier chip AD8066 for signal conditioning, and is used for sensor signal amplification and filtering of the 4-way servos of the 4-way angular displacement sensors.

[0049] The power supply module includes a first power supply module and a second power supply module;

[0050] The first power module is used to supply power to the low-power unit carried by the middle printed circuit board through the switching of the first interlayer flexible printed circuit board;

[0051] Specifically, the power conversion LTM4622 used is a single-channel 5V / 5A step-down micro μ-Module module with built-in switching DC / DC regulator, MOSFET, inductor and supporting circuits. Only a few capacitors and resistors are required on the periphery.

[0052] The second power supply module is used to supply power to the embedded digital processing module, including power conversion chips LTM4622, LTM8078 and LTM4668A;

[0053] LTM4622 is a dual-channel positive and negative voltage μ-Module module, each channel output current 1A, similarly, the peripheral configuration circuit is relatively small, suitable for bipolar power supply of operational amplifier;

[0054] LTM8078 is a dual-channel positive voltage μ-Module module used to power the DSP.

[0055] The LTM4668A is a four-channel μ-Module regulator module with an output current of 1.2A per channel. It integrates a switch controller, power FET, inductor and other supporting components, which simplifies the design process while reducing power consumption and board space. It supports frequency synchronization, multi-phase operation, optional burst mode operation, 100% duty cycle and low IQ operation. The high switching frequency and current mode architecture can make very fast transient responses to line and load changes. The LTM4668A generates a pin voltage of 3.3V and a core voltage of 1.2V; the LTM8078 is a dual-channel μ-Module regulator with an output current of 1.4A, 3.3V and 1.2V per channel. It is used to power FPGAs.

[0056] The telemetry control unit also includes a power monitoring chip TPS8033, which is used to monitor the control power supply 28V and the drive power supply 28V of the entire electronic system, and send the monitoring results to the outside through the high-speed communication module.

[0057] Specifically, Figure 3 As shown, the middle layer printed circuit board is a rigid-flexible integrated printed circuit board, and the rigid area of ​​the printed circuit board adopts a split layout, which is divided into a first middle layer rigid area, a second middle layer rigid area, a third middle layer rigid area and a fourth middle layer rigid area of ​​the same shape and 90° apart to form a circle; adjacent middle layer rigid areas are connected by four middle layer flexible printed circuit boards (the first middle layer flexible area, the second middle layer flexible area, the third middle layer flexible area and the fourth middle layer flexible area);

[0058] In order to reduce the space occupied and increase the connection strength, each middle-layer flexible area is connected to the corner of the adjacent middle-layer rigid area. The middle-layer printed circuit board effectively prevents the mechanical stress problem after the installation of large-area rigid printed circuit boards and large-mass devices through the rigid-flex integrated structure.

[0059] Each middle-layer rigid zone corresponds to a servo, carries and installs a low-power module, and the four low-power modules carried by the four middle-layer rigid zones constitute a low-power unit of the servo electronic system; each low-power module is used to process the sensor information and electric mechanical lock control information of the corresponding servo; and the middle-layer flexible printed circuit board connected between adjacent middle-layer rigid zones is used to form an information transmission area to transmit the sensor information and electric mechanical lock control information between the four middle-layer rigid zones.

[0060] Specifically, one end of the first interlayer flexible printed circuit board is connected to the top layer printed circuit board through the first plug port, and the other end is connected to one of the four middle layer rigid zones to form a rigid-flexible integrated structure (for example, the first middle layer rigid zone); the first plug port adopts J30JZ-31ZK; in this way, by bending the first interlayer flexible printed circuit board, a cable-free three-dimensional layout of the top layer printed circuit board and the middle layer printed circuit board is realized.

[0061] Through the first interlayer flexible printed circuit board and the middle layer flexible printed circuit board, the sensing information processed by the low-power module on each middle layer rigid area is transmitted to the telemetry control unit of the top layer printed circuit board; the electric mechanical lock control logic generated by the telemetry control unit is output to each low-power module.

[0062] Specifically, each low-power module includes an electric mechanical lock control switch MOS tube, a current and temperature signal conditioning interface, and an angular displacement signal conditioning interface;

[0063] Among them, the electric mechanical lock control switch MOS tube is used to amplify the power of the electric mechanical lock control logic generated by the telemetry control unit, so that the output control signal can control the corresponding electric mechanical lock to lock or unlock the motor according to the control logic. The driving power supply of the electric mechanical lock control switch MOS tube comes from the power supply voltage output by the first power module on the top printed board connected through the first inter-layer flexible printed board bridge. No power module is set on the middle printed board, which can reduce the interference of power leakage interference signals on the low-power sensor acquisition signal.

[0064] The angular displacement signal conditioning interface is used to condition the angle sensor information of the corresponding servo. The angle sensor for collecting angle sensor information is a resistive sensor. The 0~4.7K ohm resistance of the sliding resistor represents an angle of 0~360, which is generated into a stable ±10V through the AD8066 operational amplifier; the angular displacement signal conditioning interface connects the output voltage of the sliding end of the sliding resistor to the analog-to-digital converter AD7606A of the top printed board through the first interlayer flexible printed board to collect the angle information.

[0065] The current and temperature signal conditioning interface is used to condition the current and temperature sensing information of the corresponding servo. The temperature sensing information is collected by the temperature sensor PT1000, and a 1mA constant current source is generated by the voltage reference TL431. The temperature information can be obtained by connecting to the thermistor. The current sensing information is collected by the current sensor resistive LA150P, and the signal conditioning method and transmission method are consistent with the collection of angle information.

[0066] More specifically, the connection between each middle-layer rigid zone and the angle, temperature and current sensors and the electric mechanical lock also adopts a cable-free rigid-flexible integrated structure; that is, each middle-layer rigid zone is also connected to the angle, temperature and current sensors through a flexible printed circuit board ZC that adopts a rigid-flexible integrated structure; and is also connected to the electric mechanical lock through a flexible printed circuit board ZS that adopts a rigid-flexible integrated structure.

[0067] Specifically, the installation structure diagram of the middle printed circuit board is as follows Figure 4 As shown, the bending operation of the first interlayer flexible printed circuit board enables the top layer printed circuit board and the middle layer printed circuit board to be connected through J30JZ-31ZK; the middle layer printed circuit board is plugged into the angle, temperature and current sensors by bending the flexible printed circuit board ZC; the middle layer printed circuit board is plugged into the electric mechanical lock by bending the flexible printed circuit board ZS; thus, by disconnecting the plug-in interface with the top layer printed circuit board, the angle, temperature and current sensors and the electric mechanical lock, the middle layer printed circuit board can be independently separated from the electronic system for easy detection, maintenance and replacement.

[0068] Specifically, Figure 5 As shown, the sub-middle layer printed circuit board includes four sub-middle layer units with the same shape and structure;

[0069] Each secondary middle layer unit includes a rigid board, a first middle layer flexible board, a second middle layer flexible board, and an adapter board; the rigid board, the first middle layer flexible board, and the second middle layer flexible board adopt a rigid-flexible integrated structure; the rigid board and the adapter board are interconnected by a 90-degree bent pin plug-in method;

[0070] The rigid plate is used to carry and install the power drive module; the rigid plates of the four secondary middle layer units are used to carry and install the power drive modules of the four steering gears.

[0071] The first inter-middle layer flexible board and the second inter-middle layer flexible board are used to connect adjacent sub-middle layer units through the plug-in ports to form a control information transmission area;

[0072] Optionally, the first middle layer flexible plate and the second middle layer flexible plate are located on opposite sides of the rigid plate, one end forms a rigid-flexible integrated structure with the rigid plate, and the other end is installed with a plug-in port. Each secondary middle layer flexible plate is bent at a certain horizontal angle so that it is flat after being connected through the plug-in port. After being connected, the four secondary middle layer units are arranged in a circle at 90° intervals.

[0073] The plug-in interface between the rigid board and the adapter board is located on the outside of the rigid board relative to the surrounding structure. Through plugging with the rigid board, it is used to transfer the driving power output by the power supply unit to the rigid board to power the power drive module, transfer the motor drive signal output by the power drive module to the motor, and transfer the motor Hall signal to the power drive module.

[0074] The motor and Hall signal transfer flexible printed circuit board with a rigid-flexible integrated structure is connected to the three-phase terminals and Hall signal terminals of the brushless motor through the connector J112-8T3HS to achieve cable-free connection.

[0075] The other end of the second interlayer flexible printed circuit board forms a rigid-flexible integrated structure with one of the four sub-middle layer units; through the second interlayer flexible printed circuit board and the first inter-middle layer flexible board and the second inter-middle layer flexible board of each sub-middle layer unit, the motor control command output by the telemetry control unit is output to the power drive module carried by each sub-middle layer unit.

[0076] Specifically, one end of the second interlayer flexible printed circuit board is connected to the top layer printed circuit board through the second plug-in port, and the other end is connected to one of the four secondary middle layer units to form a rigid-flexible integrated structure (for example, the first middle layer unit); the second plug-in port adopts J30JZ-31ZK; in this way, by bending the second interlayer flexible printed circuit board, a cable-free three-dimensional layout of the top layer printed circuit board and the middle layer printed circuit board is realized.

[0077] Specifically, the third interlayer flexible printed circuit boards include four pieces, one end of each of which is connected to a transfer board of a secondary middle layer unit to form a rigid-flexible integrated structure, and the other end is connected to the bottom layer printed circuit board through a plug-in port to provide high and low voltage power supply voltages to each power driving module.

[0078] The power drive module carried by each sub-middle unit is mainly used to generate the three-phase voltage required for the rotation of the brushless motor according to the collected motor rotor Hall sensor information and the PWM&DIR control logic output by the telemetry control unit. Specifically, it includes a drive logic generation module, a drive amplifier module and a power amplifier module;

[0079] The drive logic generation module uses TI's brushless motor dedicated control chip UCC3626 as the control core. It has hardware resources such as Hall signal decoding circuit, triangular wave oscillator and comparator, a current sensing amplifier and absolute value circuit, which simplifies the design of the control circuit; UCC3626 converts the Hall signal received by the rotor position input into six outputs for controlling the external power tube; the triangular wave oscillator and comparison latch can provide voltage or current type PWM control; UCC3626 can control the operation mode of the power tube; the internal integrated current amplifier can be used for current closed-loop control; the duty cycle output is precisely controlled; the internal precision oscillator is the same as the synchronous main clock source.

[0080] The drive amplifier module uses amplifier IR2130.

[0081] The power amplifier module uses the IR company's Direct FET MOSFET device IRF6643, which has a maximum supply voltage of 150V and a rated current of 35A. The metal can structure provides double-sided cooling, excellent heat dissipation and higher efficiency. The key performance parameters of Rds, Qg and Qgd inside the power tube determine the conduction, switching and reverse recovery losses of the device, which ensures that a single small-volume MOSFET device can operate at a higher current level.

[0082] The installation structure diagram of a secondary middle unit is as follows: Figure 6 As shown, since the power drive module carried by the secondary middle layer unit is a high voltage and high current module, it is a module that is prone to failure during testing or actual use. Therefore, the rigid board of each secondary middle layer unit carrying the power drive module is connected through a plug-in port, and the secondary middle layer unit can be replaced by simply plugging and unplugging. In this way, the advantages are prominent during the disassembly process of the consumable power device, and the system has good maintainability. The normal sudden change of current in the power amplifier module will cause electromagnetic compatibility problems. This embodiment also realizes the effective packaging of electromagnetic signals by sealing the power MOS tube through the heat dissipation shell.

[0083] like Figure 7 As shown, the bottom printed circuit board is an integrated rigid printed circuit board, which carries and installs an external power supply interface and four power supply circuits corresponding to the four secondary middle layer units; it is used to distribute the external 28V power supply circuit to the four power supply circuits; each power supply circuit performs two-way EMI filtering on the external 28V to form a controller 28V power supply and a driver 28V power supply, wherein the driver 28V power supply outputs a high-voltage power supply after energy storage in the energy storage module.

[0084] Specifically, the power supply circuit includes a first filter, a second filter, a transient suppressor and an energy storage module;

[0085] The first filter filters the external 28V voltage and outputs a 28V power supply to the controller;

[0086] The second filter filters the external 28V voltage and outputs a 28V power supply for the driver;

[0087] The first filter and the second filter both use EMI filter HDF-CE03F to match electromagnetic compatibility. The EMI filter is used to filter out high-frequency clutter and interference signals in the power supply of the missile, and prevent the electromagnetic radiation generated by the power module from leaking to the outside, so as to reduce interference to the outside world.

[0088] Transient suppressors are used to suppress spikes and surges of external power supplies. The nominal input of the missile product is a 28V power supply, and the maximum allowable is 40V. In the case of power spikes and surges, a protection circuit is used to keep the input voltage below 40V to ensure the normal operation of the missile-borne electronic equipment. Commonly used protection schemes are composed of diodes, inductors, high-voltage capacitors and transient suppressors (TVS tubes), etc. The circuit reliability is poor and is not conducive to compact product design. LTC4364 is an anti-surge suppressor with an ideal diode controller. It has a wide voltage operating range of 4 to 80V and can be used in circuits such as surge protection to protect the load from damage by high-voltage transients. LTC4364 can accurately monitor the overvoltage and undervoltage status of the input power supply, and limit and adjust the output during overvoltage and undervoltage by controlling the voltage drop across the external N-channel MOSFET. In the design, the circuit effectively suppresses the 40V surge during the voltage surge and avoids damage to the load due to continuous high voltage.

[0089] The energy storage module is used to provide power supply for the MOSFET device of the power amplifier module carried by the secondary middle layer printed circuit board. Specifically, the energy storage module adopts the energy storage capacitor TW3518.

[0090] In order to realize the cable-free power supply line, more specifically, the power supply line design of this embodiment is as follows:

[0091] The third interlayer flexible printed circuit board connects the controller 28V power supply, the driver 28V power supply and the high-voltage power supply to the corresponding sub-middle layer unit in the sub-middle layer printed circuit board; the controller 28V power supply is transferred to the top layer printed circuit board through the second interlayer flexible printed circuit board connected to the sub-middle layer printed circuit board to power the telemetry control unit; after the secondary power supply module of the telemetry control unit performs voltage conversion, it is output to the middle layer printed circuit board through the first interlayer flexible printed circuit board to provide driving voltage for the MOS tube of the electric mechanical lock driving circuit.

[0092] In order to better achieve electromagnetic shielding, a conductive layer is laminated on the flexible board of this embodiment to shield external electromagnetic interference and avoid signal distortion during signal transmission on the flexible board.

[0093] In order to more clearly express the relative position relationship between the layers, Figure 8 It is an installation diagram of the printed circuit board in a three-dimensional electronic system, so that the connection relationship between each layer of the printed circuit board is clearer.

[0094] To better understand the servo control implementation of the electronic system, Fig. 9 It is a schematic diagram of the composition and connection of the specific circuit modules of the electronic system, so as to make the function of the electronic system clearer.

[0095] In summary, this embodiment adopts the planar design of the rigid-flexible printed circuit board to replace the internal cable connection, and the three-dimensional layout after the flexible printed circuit board is bent makes the structure more compact, occupies less space, and has more optimized processability;

[0096] The three-dimensional design of rigid-flex printed circuit boards saves assembly time, omits the process of electrical welding and on-site inspection, increases the design assurance ratio of product quality, and weakens the assurance of process; it saves personnel costs, ensures quality, and reduces the probability of misoperation.

[0097] It is conducive to mass production, has high efficiency and high yield rate, and ensures rapid design and rapid assembly, providing strong support for the modernization of equipment.

[0098] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A three-dimensional electronic system for a steering gear based on a rigid-flex printed circuit board, characterized in that: It includes four layers of printed circuit boards stacked from top to bottom; the top printed circuit board carries and installs the telemetry control unit of the steering gear, the middle printed circuit board carries and installs the low-power unit of the steering gear, the second middle printed circuit board carries and installs the power drive unit of the steering gear, and the bottom printed circuit board carries and installs the power supply unit; The top printed board and the middle printed board are connected through the first interlayer flexible printed board, which is used for the control and sensor signal transmission between the telemetry control unit and the low power unit; the top printed board and the second interlayer flexible printed board are connected through the second interlayer flexible printed board, which is used for the control signal transmission between the telemetry control unit and the power drive unit; the second interlayer flexible printed board and the bottom printed board are connected through the third interlayer flexible printed board, which is used for the power supply distribution from the power supply unit to the power drive unit; The sub-middle layer printed circuit board comprises four sub-middle layer units having the same shape and structure; Each secondary middle layer unit includes a rigid board, a first middle layer flexible board, a second middle layer flexible board, and a transfer board; the rigid board, the first middle layer flexible board, and the second middle layer flexible board adopt a rigid-flexible integrated structure, and the rigid board and the transfer board are interconnected by a 90-degree bent pin plug-in method; The rigid plate is used to carry and install the power drive module; The first inter-middle layer flexible board and the second inter-middle layer flexible board are used to connect adjacent sub-middle layer units through the plug-in ports to form a control information transmission area; The adapter board is used to transfer the driving power output by the power supply unit to the rigid board to power the power driving module, transfer the motor driving signal output by the power driving module to the motor, and transfer the motor Hall signal to the power driving module.

2. The three-dimensional electronic system for a steering gear according to claim 1, characterized in that: The top-layer printed circuit board is an integrated rigid printed circuit board, which is connected to one end of the first interlayer flexible printed circuit board through a first plug port; and is connected to one end of the second interlayer flexible printed circuit board through a second plug port; the telemetry control unit adopts a DSP+FPGA architecture, obtains the servo sensor signal from the first plug port and combines it with the external telemetry control signal to generate a servo control signal, and outputs the servo control signal to the power drive unit carried by the secondary middle layer printed circuit board through the second plug port.

3. The three-dimensional electronic system for a steering gear according to claim 2, characterized in that: The middle layer printed circuit board is a rigid-flexible integrated printed circuit board, and the rigid area of ​​the printed circuit board adopts a split layout, which is divided into a first middle layer rigid area, a second middle layer rigid area, a third middle layer rigid area and a fourth middle layer rigid area of ​​the same shape and 90° apart to form a circle; adjacent middle layer rigid areas are connected by four middle layer flexible printed circuit boards; A low-power module is carried and mounted on each middle rigid zone for processing sensing information and electromechanical lock control information; The middle-layer flexible printed circuit board connected between adjacent middle-layer rigid areas is used to form an information transmission area to transmit sensor information and electric mechanical lock control information between the four middle-layer rigid areas.

4. The three-dimensional electronic system for a steering gear according to claim 3, characterized in that: The other end of the first interlayer flexible printed circuit board forms a rigid-flexible integrated structure with one of the four middle-layer rigid areas; the sensing information processed by the low-power module on each middle-layer rigid area is transmitted to the telemetry control unit of the top-layer printed circuit board through the first interlayer flexible printed circuit board and the middle-layer flexible printed circuit board; the electric mechanical lock control logic generated by the telemetry control unit is output to each low-power module.

5. The three-dimensional electronic system for a steering gear according to claim 4, characterized in that: Each middle-layer rigid zone is also connected to the angle, temperature and current sensors through a flexible printed circuit board ZC that adopts a rigid-flexible integrated structure; and is also connected to the electric mechanical lock through a flexible printed circuit board ZS that adopts a rigid-flexible integrated structure.

6. The three-dimensional electronic system for a steering gear according to claim 3, characterized in that: The other end of the second interlayer flexible printed circuit board forms a rigid-flexible integrated structure with one of the four sub-middle layer units; through the second interlayer flexible printed circuit board and the first inter-middle layer flexible board and the second inter-middle layer flexible board of each sub-middle layer unit, the motor control command output by the telemetry control unit is output to the power drive module carried by each sub-middle layer unit.

7. The three-dimensional electronic system for a steering gear according to claim 6, characterized in that: The third interlayer flexible printed circuit boards include four pieces, one end of each of which is connected to a transfer board of a secondary middle layer unit to form a rigid-flexible integrated structure, and the other end is connected to the bottom layer printed circuit board through a plug-in port to provide high and low voltage power supply voltages to each power driving module.

8. The three-dimensional electronic system for a steering gear according to claim 6, characterized in that: The bottom printed circuit board is an integrated rigid printed circuit board, which carries and installs an external power supply interface and four power supply circuits corresponding to the four secondary middle layer units; it is used to distribute the external 28V power supply circuit to the four power supply circuits; each power supply circuit performs two-way EMI filtering on the external 28V to form a controller 28V power supply and a driver 28V power supply, wherein the driver 28V power supply outputs a high-voltage power supply after energy storage in the energy storage module.

9. The three-dimensional electronic system for a steering gear according to claim 3, characterized in that: The third interlayer flexible printed circuit board connects the controller 28V power supply, the driver 28V power supply and the high-voltage power supply to the corresponding sub-middle layer unit in the sub-middle layer printed circuit board; the controller 28V power supply is transferred to the top layer printed circuit board through the second interlayer flexible printed circuit board connected to the sub-middle layer printed circuit board to power the telemetry control unit; after the secondary power supply module of the telemetry control unit performs voltage conversion, it is output to the middle layer printed circuit board through the first interlayer flexible printed circuit board to provide driving voltage for the MOS tube of the electric mechanical lock driving circuit.

Images