Helicopter key destroying circuit and method

Abstract

The invention discloses a helicopter key destroying circuit and method. A single-pole double-throw control switch and a control end are arranged in the electromagnetic relay (3), a common contact of the single-pole double-throw control switch is connected with an onboard power supply, a normally closed contact of the single-pole double-throw control switch is suspended, and a normally open contact of the single-pole double-throw control switch is connected with a key destroying pin of key destroying equipment; the onboard power supply is also connected with the positive electrode of the control end of the electromagnetic relay (3) through the control switch (2); and the negative electrode of the control end of the electromagnetic relay (3) is grounded with the onboard power supply. The problem that in the existing helicopter avionics field, a key-destroying circuit with a single switch cannot meet the key-destroying requirements of many key-destroying devices is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of helicopter avionics, and in particular relates to a helicopter key-destroying circuit and method. Background Art

[0002] In the existing helicopter avionics field, onboard communication equipment is equipped with a confidentiality module to achieve confidential communication, store keys and encrypt and decrypt data transmission; the military map information loaded by the integrated display system is also confidential information. These confidential information needs to be destroyed at critical moments to prevent the possibility of leakage. There are two main ways to achieve the destruction of the above confidential information. One is hard destruction, which is achieved by powering on and burning the hardware storing confidential information. The other is soft destruction. After the device receives the destruction signal, the software executes the erase program to delete the confidential information. Both methods are achieved through the key destruction circuit.

[0003] Currently, the commonly used key destruction circuit is composed of a switch. When the switch is turned on, a 28V DC power supply is provided to all devices storing confidential information (hereinafter referred to as key destruction devices) at the same time, which serves as a working power supply for hard destruction or a key destruction signal for soft destruction. After receiving the key destruction power supply, the key destruction device executes the operation of destroying confidential information, i.e. destroying the key.

[0004] However, as more and more confidentiality modules are installed on board or devices storing confidential information are added, and the current required for hard destruction is generally above 5A, there are too many devices connected to the key-destroying switch and the current passing through is too large. The control method of this single switch can no longer meet the key-destroying needs of more key-destroying devices on board. Summary of the invention

[0005] The purpose of the present invention is to provide a helicopter key destruction circuit and method. The present invention solves the problem in the existing helicopter avionics field that a single switch key destruction circuit cannot meet the key destruction requirements of multiple key destruction devices.

[0006] The technical solution of the present invention is: a helicopter key-destroying circuit, including an electromagnetic relay, a single-pole double-throw control switch and a control end are arranged inside the electromagnetic relay, the common contact of the single-pole double-throw control switch is connected to the on-board power supply, the break contact of the single-pole double-throw control switch is suspended, and the make contact is connected to the key-destroying pin of the key-destroying device; the on-board power supply is also connected to the positive pole of the electromagnetic relay control end via the control switch, and the negative pole of the electromagnetic relay control end is connected to the ground of the on-board power supply.

[0007] In the aforementioned helicopter key destruction circuit, more than one set of single-pole double-throw control switches are provided in the electromagnetic relay. The common contacts of each single-pole double-throw control switch are connected to the onboard power supply via a permanent connector A, and the normally closed contacts of each single-pole double-throw control switch are connected to the key destruction pin of the key destruction device via a permanent connector B.

[0008] In the aforementioned helicopter key-destroying circuit, the control switch is connected to the positive pole of the electromagnetic relay control terminal via a permanent connector C, and the negative pole of the electromagnetic relay control terminal is also connected to the ground of the onboard power supply via a permanent connector C.

[0009] In the aforementioned helicopter key-destroying circuit, the common contact of the single-pole double-throw control switch and the control switch are connected to the onboard power supply via the key-destroying circuit breaker.

[0010] In the aforementioned helicopter key-destroying circuit, a freewheeling diode is connected between the positive and negative poles of the electromagnetic relay control terminal.

[0011] In the aforementioned helicopter key destruction circuit, the electromagnetic relay uses an aviation DC load power supply type electromagnetic relay.

[0012] In the aforementioned helicopter key destruction circuit, the electromagnetic relay model is J500-D4A.

[0013] In the above-mentioned helicopter key destruction circuit key destruction method, under normal conditions, the electromagnetic relay is powered off, and the key destruction device is disconnected from the onboard power supply; the control switch is turned on, the electromagnetic relay control end is powered on, the electromagnetic relay is started, and the normally closed contact connects the key destruction device to the onboard power supply, starting the key destruction.

[0014] The advantages of the present invention are:

[0015] 1. The present invention meets the key destruction requirements of a large number of key destruction devices through the design of the key destruction circuit, does not add a new key destruction switch, and does not change the original machine key destruction operation mode, while avoiding the following problems existing in the traditional key destruction circuit:

[0016] a) Ordinary switches cannot withstand the passage of large currents. Switches that can withstand large currents are large in size, inconvenient to install in the cockpit, and have high costs.

[0017] b) When there are many key-destroying devices, there will be more wires connected to one end of the switch, making installation difficult, affecting the installation of surrounding equipment and components, and increasing the risk of looseness.

[0018] c) Directly controlling multiple power supplies through switches is an unreasonable design.

[0019] 2. The invention has a simple structure and is easy to operate. It does not change the original key-destroying operation mode and does not increase the burden on the driver.

[0020] 3. The present invention can realize the access of more key-destroying devices, with small changes on the machine, low cost and high efficiency;

[0021] 4. The present invention has strong adaptability and low risk. The power-on control of large current is realized through relays, which can better adapt to and meet the key destruction requirements of more key destruction devices on the aircraft, and also avoid the risks brought by the on-off control of large current; at the same time, the added freewheeling diode design can effectively protect the circuit during the key destruction inspection. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the circuit structure of the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0024] The features and illustrative embodiments of various aspects of the present invention will be described in detail below. In the detailed description below, many specific details are proposed to provide a comprehensive understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is by no means limited to any specific settings and methods proposed below, but covers any improvements, replacements and modifications of structures, methods, devices without departing from the spirit of the present invention. In the accompanying drawings and the following description, known structures and technologies are not shown to avoid unnecessary ambiguity in the present invention.

[0025] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other, and the embodiments can refer to and quote each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0026] Embodiment 1. A helicopter key-destroying circuit mainly consists of a key-destroying circuit breaker, a control switch, an electromagnetic relay, a freewheeling diode, and a permanent connector.

[0027] 1) Destroy key circuit breaker

[0028] In the design of this key-destroying circuit, the key-destroying circuit breaker is mainly used to provide the key-destroying power supply and provide protection for the circuit. When the key-destroying circuit breaker is connected, it provides the power required for the key-destroying circuit. When it is disconnected, the entire key-destroying circuit has no power supply. Under normal conditions, it should be in the connected state.

[0029] Circuit breakers are automatic protection switches, usually bimetallic structures, small in size, easy to use and operate, and widely used in airplanes and helicopters. The selection of key-destroying circuit breakers should be aviation circuit breakers, and should be determined according to the current required by all key-destroying devices, that is, to ensure that all key-destroying devices can achieve confidential information destruction and protect the circuit. For example, DBF-25 circuit breakers can support a maximum current supply of 25A.

[0030] 2) Control switch

[0031] In the design of this key-destroying circuit, the control switch is mainly used to realize the on-off control of the key-destroying circuit and control the working state of the electromagnetic relay. The power supply connected to the control switch is the same as the key-destroying power supply, ensuring that when the key-destroying power supply is turned on, the key-destroying cable can be powered on and work synchronously.

[0032] When the control switch is turned on, the current is transmitted to the control end of the electromagnetic relay through the switch, so that the internal coil of the electromagnetic relay is energized, generating an electromagnetic effect. The armature overcomes the pulling force of the return spring under the action of electromagnetic force attraction, so that the moving contact and the static contact are attracted. After the switch is turned off, the control end of the electromagnetic relay is de-energized, so that the internal coil of the electromagnetic relay is de-energized, the electromagnetic force disappears, and the armature releases the moving contact and the static contact under the pulling force of the return spring.

[0033] The selection of the control switch can be a common aviation switch or a switch used in an existing key-destroying circuit because the current required to control the on and off of the electromagnetic relay is relatively small.

[0034] c) Electromagnetic relay

[0035] In this key-destroying circuit design, the electromagnetic relay is mainly used to realize the connection between the key-destroying power supply and the key-destroying device. The output end of the electromagnetic relay is connected to all the key-destroying devices of the original machine; the input end is connected to the key-destroying power supply, in which the break contact is suspended and not connected, and the close contact is connected to the key-destroying power supply to ensure that the key-destroying device has no key-destroying power supply under normal conditions.

[0036] When the electromagnetic relay is not powered, the key-destroying device is not connected to the key-destroying power supply and the key is not destroyed; when the electromagnetic relay is powered and works, the key-destroying device is connected to the key-destroying power supply and the key is destroyed.

[0037] The electromagnetic relay should be an aviation relay that can pass large currents. The electromagnetic relay is used on helicopters. Considering the power supply characteristics of helicopters, a DC load power supply type electromagnetic relay should be selected. Considering the use of the key-destroying circuit, a switch type electromagnetic relay should be selected. For example, the J500-D4A electromagnetic relay can support a maximum current on-off control of 25A.

[0038] d) Freewheeling diode

[0039] In the design of this key-destroying circuit, the freewheeling diode mainly plays the role of freewheeling (anti-spike).

[0040] The diode connected in parallel at both ends of the inductor is called a freewheeling diode. The internal coil of the electromagnetic relay is an inductor. When the key-destroying circuit is inspected, the internal coil of the electromagnetic relay will produce a sudden change in voltage and current when controlled by the control switch, which will affect the key-destroying circuit and other equipment and circuits on the aircraft. This problem is solved by adding a freewheeling diode to the key-destroying circuit.

[0041] The freewheeling diode should be an aviation diode, and the diode that can play a freewheeling role should be selected.

[0042] e) Permanent joints

[0043] Permanent connectors are used to connect wires in this circuit design. They are actually metal sleeves that insert pre-connected wires and cables from both ends and then mechanically crimp them together.

[0044] The permanent connector should be aviation-grade, and its specifications should be determined according to the wire cross-section of the required connecting wire. Permanent connector A5 can be used to connect wires with large currents, i.e., large cross-sections, and permanent connector C6 can be used to connect wires with small currents, i.e., small cross-sections.

[0045] For specific circuit structure, see Figure 1 , electromagnetic relay 3, the electromagnetic relay 3 is provided with a single-pole double-throw control switch and a control end, the common contact of the single-pole double-throw control switch is connected to the on-board power supply, the moving-break contact of the single-pole double-throw control switch is suspended, and the moving-make contact is connected to the key-destroying pin of the key-destroying device; the on-board power supply is also connected to the positive pole of the control end of the electromagnetic relay 3 through the control switch 2, and the negative pole of the control end of the electromagnetic relay 3 is connected to the ground of the on-board power supply.

[0046] The aforementioned electromagnetic relay 3 is provided with more than one set of single-pole double-throw control switches, the common contacts of each single-pole double-throw control switch are connected to the on-board power supply via a permanent connector A5, and the normally closed contacts of each single-pole double-throw control switch are connected to the key-destroying pin of the key-destroying device via a permanent connector B7.

[0047] The aforementioned control switch 2 is connected to the positive pole of the control terminal of the electromagnetic relay 3 via a permanent connector C6, and the negative pole of the control terminal of the electromagnetic relay 3 is also connected to the ground of the onboard power supply via a permanent connector C6.

[0048] The common contact of the aforementioned single-pole double-throw control switch and the control switch 2 are both connected to the onboard power supply via the key-destroying circuit breaker 1.

[0049] A freewheeling diode 4 is connected between the positive and negative poles of the control terminal of the aforementioned electromagnetic relay 3 .

[0050] The aforementioned electromagnetic relay 3 is an electromagnetic relay of the DC load power supply type for aviation.

[0051] The aforementioned electromagnetic relay 3 is model J500-D4A.

[0052] In the above-mentioned method for destroying the key of the helicopter key destruction circuit, under normal conditions, the electromagnetic relay 3 is powered off, and the key destruction device is disconnected from the onboard power supply; the control switch 2 is turned on, the control end of the electromagnetic relay 3 is powered on, the electromagnetic relay 3 is started, and the normally closed contact connects the key destruction device to the onboard power supply, thereby starting the key destruction.

[0053] To ensure that the circuit connection is reliable and effective, the key-destroying circuit is checked for connection. The specific checks are as follows:

[0054] To avoid the destruction of confidential information during the inspection process, ensure that the connectors of the key-destroying devices are disconnected before the inspection. Use a multimeter to test the DC voltage at the key-destroying pins of each key-destroying device.

[0055] When the control switch 2 is disconnected and the key-destroying circuit breaker 1 is connected, the DC voltage detected by the multimeter is 0V, that is, no voltage; after the control switch 2 is connected, the multimeter should detect a DC voltage of 28V, indicating that the key-destroying circuit is working normally.

[0056] After the inspection is completed, make sure that control switch 2 is in the OFF position.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the field can easily think of various equivalent modifications or substitutions within the technical scope disclosed by the present invention, and these modifications or substitutions should all be covered within the protection scope of the present invention.

Claims

1. A helicopter key destruction circuit, characterized in that: include: The electromagnetic relay (3) is provided with a single-pole double-throw control switch and a control terminal, the common contact of the single-pole double-throw control switch is connected to the onboard power supply, the break contact of the single-pole double-throw control switch is suspended, and the close contact is connected to the key-destroying pin of the key-destroying device; the onboard power supply is also connected to the positive pole of the control terminal of the electromagnetic relay (3) via the control switch (2), and the negative pole of the control terminal of the electromagnetic relay (3) is connected to the ground of the onboard power supply.

2. The helicopter key-destroying circuit according to claim 1, characterized in that: The electromagnetic relay (3) is provided with one or more single-pole double-throw control switches. The common contacts of the single-pole double-throw control switches are connected to the onboard power supply via a permanent connector A (5). The normally closed contacts of the single-pole double-throw control switches are connected to the key-destroying pin of the key-destroying device via a permanent connector B (7).

3. The helicopter key-destroying circuit according to claim 1, characterized in that: The control switch (2) is connected to the positive pole of the control end of the electromagnetic relay (3) via a permanent connector C (6), and the negative pole of the control end of the electromagnetic relay (3) is also connected to the ground of the onboard power supply via a permanent connector C (6).

4. The helicopter key-destroying circuit according to claim 1, characterized in that: The common contact of the single-pole double-throw control switch and the control switch (2) are both connected to the onboard power supply via the key-destroying circuit breaker (1).

5. The helicopter key-destroying circuit according to claim 1, characterized in that: A freewheeling diode (4) is connected between the positive and negative electrodes of the control terminal of the electromagnetic relay (3).

6. The helicopter key-destroying circuit according to claim 1, characterized in that: The electromagnetic relay (3) uses an electromagnetic relay of the DC load power supply type for aviation.

7. The helicopter key-destroying circuit according to claim 6, characterized in that: The electromagnetic relay (3) model is J500-D4A.

8. A method for destroying a key of a helicopter key-destroying circuit according to any one of claims 1 to 7, characterized in that: Under normal conditions, the electromagnetic relay (3) is powered off, and the key destroying device is disconnected from the aircraft power supply; the control switch (2) is turned on, the control end of the electromagnetic relay (3) is powered on, the electromagnetic relay (3) is started, and the normally closed contact connects the key destroying device to the aircraft power supply, thereby starting the key destroying device.

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