Helicopter audio switching circuit and method

Abstract

The invention discloses a helicopter audio switching circuit and method. A calling channel of the original machine equipment (1) is electrically connected with a calling channel of the built-in communication system (3) through a normally closed pin of the electromagnetic relay A (4), and a listening channel of the original machine equipment (1) is electrically connected with a listening channel of the built-in communication system (3) through a normally closed pin of the electromagnetic relay B (5); a calling channel of the newly-installed device (2) is electrically connected with a calling channel of the built-in communication system (3) through a normally-open pin of the electromagnetic relay A (4), and a listening channel of the newly-installed device (2) is electrically connected with a listening channel of the built-in communication system (3) through a normally-open pin of the electromagnetic relay B (5). One end of a parallel branch formed by connecting the control ends of the electromagnetic relays A and B in parallel is connected with the change-over switch (6), the other end of the parallel branch is connected with the onboard power ground, and the change-over switch (6) is connected with a working power supply of the newly-installed equipment (2). According to the invention, sharing of the audio channel of the newly-added device and the audio channel of the original device is realized, and manual switching control is carried out by using the audio switching switch, so that the audio channel requirement of the newly-added device is met, and the call in the original device does not need to be changed.

Description

Technical Field

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

[0002] In the process of using helicopters, in order to meet various business needs such as agricultural and forestry spraying, medical emergency, etc., helicopters are usually modified accordingly. After installing appropriate equipment, helicopters can perform specific work tasks. If the installed equipment has voice requirements, especially equipment that requires external voice communication, the problem of insufficient audio channels in the original aircraft's internal communication system may be encountered.

[0003] There are two main ways to solve the problem of insufficient machine-to-machine audio channels: one is to replace the original machine's intercom system or improve and upgrade it, add corresponding machine-to-machine audio channels, and provide audio interfaces for newly installed equipment; the other is to install audio processing equipment to expand the original machine's audio channels. Although these two methods can completely solve the problem of insufficient audio channels, they are costly and require a lot of changes for retrofitting only to add a few devices or a few audio channels. Summary of the invention

[0004] The purpose of the present invention is to provide a helicopter audio switching circuit and method. The present invention realizes the sharing of the audio channel of the newly added equipment with the audio channel of the original equipment, and uses the audio switching switch for manual switching control, which not only meets the audio channel requirements of the newly added equipment, but also does not need to change the original machine's internal call.

[0005] The technical scheme of the present invention is: a helicopter audio switching circuit, comprising: original equipment, newly installed equipment and an in-machine communication system; the speaking channel of the original equipment is electrically connected to the speaking channel of the in-machine communication system via the normally closed pin of an electromagnetic relay A, and the listening channel of the original equipment is electrically connected to the listening channel of the in-machine communication system via the normally closed pin of an electromagnetic relay B; the speaking channel of the newly installed equipment is electrically connected to the speaking channel of the in-machine communication system via the normally open pin of an electromagnetic relay A, and the listening channel of the newly installed equipment is electrically connected to the listening channel of the in-machine communication system via the normally open pin of an electromagnetic relay B; one end of a parallel branch formed by parallel connection of control ends of electromagnetic relays A and B is connected to a switching switch, and the other end is connected to an on-board power ground, and the switching switch is connected to a working power supply of the newly installed equipment.

[0006] In the aforementioned helicopter audio switching circuit, a newly installed equipment circuit breaker is provided between the switching switch and the newly installed equipment.

[0007] In the aforementioned helicopter audio switching circuit, a freewheeling diode A is connected between the positive and negative electrodes of the control end of the electromagnetic relay A.

[0008] In the aforementioned helicopter audio switching circuit, a freewheeling diode B is connected between the positive and negative electrodes of the electromagnetic relay B control end.

[0009] In the aforementioned helicopter audio switching circuit, the switching switch is connected to the positive poles of the control ends of the electromagnetic relays A and B via permanent connectors A and B, respectively, and the negative poles of the control ends of the electromagnetic relays A and B are connected to the ground of the onboard power supply via permanent connectors C and D, respectively.

[0010] In the aforementioned helicopter audio switching circuit, the electromagnetic relay uses an aviation DC load power supply type electromagnetic relay.

[0011] In the aforementioned helicopter audio switching circuit, the electromagnetic relay model is J400-D4A.

[0012] In the audio switching method of the above-mentioned helicopter audio switching circuit, under normal conditions, the audio of the original equipment is connected to the intercom system through the normally closed pins of electromagnetic relays A and B; when switching the audio, the switching switch is closed, the electromagnetic relays A and B are powered on, the normally closed pins are disconnected, and the normally open pins are closed and connected, and the audio of the newly installed equipment is connected to the intercom system through the normally open pins of electromagnetic relays A and B, completing the audio switching between the original equipment and the newly installed equipment.

[0013] The advantages of the present invention are:

[0014] 1. The present invention solves the problem that the audio channel of the original machine's intercom system does not meet the requirements of the installed equipment during the existing modification work, and realizes that the audio channel of the newly added equipment is shared with the audio channel of one of the original equipment, and uses an audio switching switch for manual switching control, which not only meets the audio channel requirements of the newly added equipment, but also does not need to change the intercom of the original machine.

[0015] 2. The present invention has a simple structure, convenient circuit design and operation, and requires little modification. It can realize the call function of the newly installed equipment without changing the state of the original machine, thus solving the problem of insufficient audio channels of the original machine.

[0016] 3. The present invention has significant cost-effectiveness. Without changing the hardware of the airborne equipment, the switching control method of the logic circuit constructed by switching switches and relays saves a lot of test and verification expenses caused by the modification of the airborne equipment, thereby reducing the overall equipment cost.

[0017] 4. The audio communication effect of the present invention is guaranteed. The audio transmitting and receiving channels are effectively separated through the logic circuit, and the crosstalk caused by the mixing of audio channels is reduced, so the audio call effect is guaranteed. At the same time, the designed freewheeling diode can effectively protect the circuit and reduce the impact of current mutation on airborne equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1It is a schematic diagram of the circuit structure of the present invention. DETAILED DESCRIPTION

[0019] 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.

[0020] 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.

[0021] 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.

[0022] Embodiment 1. A helicopter audio switching circuit mainly utilizes the working principle of an electromagnetic relay conversion circuit to realize the function of switching the audio circuits of two devices to access the original aircraft's intercom system, thereby solving the problem of insufficient audio channels in the original aircraft's intercom system.

[0023] The newly installed equipment needs to make audio calls, and the number of audio channel interfaces of the original machine's intercom can no longer meet its needs. It is necessary to design an audio circuit to meet its requirements. There are two ways to achieve this. One is to modify the original machine's intercom. The disadvantage is that a lot of tests are required to verify that the modified intercom meets the relevant requirements. The other is to design an audio switching circuit to realize audio channel sharing and audio channel separation to ensure clear voice.

[0024] Connect the input end of the switching switch to the power circuit breaker of the newly installed equipment, and connect the output end of the switching switch to the positive pole of the relay control end; the negative pole of the relay control end is connected to the power ground on the machine; connect the audio transceiver channels of the original equipment to the normally closed input pins of the relay, and connect the audio transceiver channels of the newly installed equipment to the normally open input pins of the relay, and connect the output end of the relay to the intercom system.

[0025] The newly installed equipment and relay are powered by the same working power supply; when the new equipment is powered on, the switch can be controlled to provide power to the relay control end at the same time, and the relay can be controlled to connect its normally open input pin with the output pin, so that the audio of the newly installed equipment is connected to the intercom system, so that the newly installed equipment can make normal audio calls. When designing this logic circuit, the control power supply of the relay is shared with the power supply of the newly installed equipment, so that the switching audio channel is allowed to be started only when the newly installed equipment is in use, and the switching of the audio channel is not allowed when the newly installed equipment is not powered on, so as to ensure the normal use of the original equipment, thereby avoiding the audio call of the original equipment being affected by misoperation when the new equipment is not powered on.

[0026] For specific circuit structure, see Figure 1 , including: original equipment 1, newly installed equipment 2 and inter-machine communication system 3; the speaking channel of the original equipment 1 is electrically connected to the speaking channel of the inter-machine communication system 3 via the normally closed pin of the electromagnetic relay A4, and the listening channel of the original equipment 1 is electrically connected to the listening channel of the inter-machine communication system 3 via the normally closed pin of the electromagnetic relay B5; the speaking channel of the newly installed equipment 2 is electrically connected to the speaking channel of the inter-machine communication system 3 via the normally open pin of the electromagnetic relay A4, and the listening channel of the newly installed equipment 2 is electrically connected to the listening channel of the inter-machine communication system 3 via the normally open pin of the electromagnetic relay B5; one end of the parallel branch formed by the control ends of the electromagnetic relays A and B in parallel is connected to the switching switch 6, and the other end is connected to the power ground on the machine, and the switching switch 6 is connected to the working power supply of the newly installed equipment 2.

[0027] In this audio switching circuit design, the switch is mainly used to realize the on-off control of the audio switching circuit power supply and control the working state of the electromagnetic relay. The power supply connected to the switch is the same as the power supply of the additional equipment, ensuring that the audio switching circuit can be powered on and work synchronously when the additional equipment is working.

[0028] When the 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 normally open. 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.

[0029] When selecting a switching switch, an ordinary aviation switch can be used because the current required to control the electromagnetic relay to switch on and off is small.

[0030] In the aforementioned helicopter audio switching circuit, a newly installed equipment circuit breaker 7 is provided between the switching switch 6 and the newly installed equipment 2 .

[0031] In the aforementioned helicopter audio switching circuit, a freewheeling diode A8 is connected between the positive and negative electrodes of the control end of the electromagnetic relay A4.

[0032] In the aforementioned helicopter audio switching circuit, a freewheeling diode B9 is connected between the positive and negative electrodes of the control end of the electromagnetic relay B5.

[0033] In the design of this audio switching circuit, the freewheeling diode mainly plays the role of freewheeling and anti-spike.

[0034] 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 audio circuit is switched by switching the switch, the internal coil of the electromagnetic relay will produce a sudden change in voltage and current, which will affect the audio switching circuit and other equipment and circuits on the aircraft. This problem is solved by adding a freewheeling diode in the audio switching circuit.

[0035] The freewheeling diode should be an aviation diode, and the diode that can play a freewheeling role should be selected.

[0036] In the aforementioned helicopter audio switching circuit, the switch 6 is connected to the positive poles of the control ends of the electromagnetic relays A and B via permanent connectors A10 and B11, respectively, and the negative poles of the control ends of the electromagnetic relays A and B are connected to the ground of the onboard power supply via permanent connectors C12 and D13, respectively.

[0037] In this audio switching circuit design, the permanent connector is used to connect the wires and realize the connection between the freewheeling diode and the relay. It is actually a metal sleeve that inserts the pre-connected wires and cables from both ends and then mechanically crimps them together.

[0038] The permanent connector selected should be an aviation-grade one, and its specification should be determined based on the conductor cross-section of the required connecting line.

[0039] In the aforementioned helicopter audio switching circuit, the electromagnetic relay uses an aviation DC load power supply type electromagnetic relay.

[0040] In the aforementioned helicopter audio switching circuit, the electromagnetic relay model is J400-D4A.

[0041] In this audio switching circuit design, the electromagnetic relay is mainly used to realize the switching of the audio circuit. The output end of the electromagnetic relay is connected to the audio channel of the original machine; the input end is connected to the audio equipment and the installed equipment used by the original machine, among which the break contact is connected to the original equipment and the make contact is connected to the installed equipment, ensuring that even if the switch is not turned on, that is, the installed equipment is not powered on, the original equipment can still use the audio channel.

[0042] When the electromagnetic relay is not energized, the original equipment in the audio switching circuit is connected to the inter-machine communication system, the original equipment can perform voice communication, and the added equipment cannot perform voice communication; when the electromagnetic relay is energized and works, the added equipment in the audio switching circuit is connected to the inter-machine communication system, the added equipment can perform voice communication, and the original equipment cannot perform voice communication.

[0043] The electromagnetic relay should be an aviation relay, and the electromagnetic relay is used on a helicopter. In view of the helicopter power supply characteristics, a DC load power supply type electromagnetic relay should be selected; in view of the switching use of the audio circuit, the current carrying capacity is very small, so a switch type electromagnetic relay should be selected. For example, the J400-D4A electromagnetic relay can support signal transmission and control.

[0044] The audio switching method of the aforementioned helicopter audio switching circuit is as follows: under normal conditions, the audio of the original device 1 is connected to the intercom system 3 via the normally closed pins of the electromagnetic relays A and B; when switching the audio, the switching switch 6 is closed, the electromagnetic relays A and B are powered on, the normally closed pins are disconnected, the normally open pins are closed and connected, and the audio of the newly installed device 2 is connected to the intercom system 3 via the normally open pins of the electromagnetic relays A and B, completing the audio switching between the original device 1 and the newly installed device 2.

[0045] 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 audio switching circuit, characterized in that: include: The original equipment (1), the newly installed equipment (2) and the inter-machine communication system (3); the speaking channel of the original equipment (1) is electrically connected to the speaking channel of the inter-machine communication system (3) via the normally closed pin of the electromagnetic relay A (4), and the listening channel of the original equipment (1) is electrically connected to the listening channel of the inter-machine communication system (3) via the normally closed pin of the electromagnetic relay B (5); the speaking channel of the newly installed equipment (2) is electrically connected to the speaking channel of the inter-machine communication system (3) via the normally open pin of the electromagnetic relay A (4), and the listening channel of the newly installed equipment (2) is electrically connected to the listening channel of the inter-machine communication system (3) via the normally open pin of the electromagnetic relay B (5); one end of the parallel branch formed by the control ends of the electromagnetic relays A and B in parallel is connected to the switching switch (6), and the other end is connected to the ground of the on-board power supply, and the switching switch (6) is connected to the working power supply of the newly installed equipment (2).

2. The helicopter audio switching circuit according to claim 1, characterized in that: A newly installed equipment circuit breaker (7) is provided between the switching switch (6) and the newly installed equipment (2).

3. The helicopter audio switching circuit according to claim 1, characterized in that: A freewheeling diode A (8) is connected between the positive and negative electrodes of the control terminal of the electromagnetic relay A (4).

4. The helicopter audio switching circuit according to claim 1, characterized in that: A freewheeling diode B (9) is connected between the positive and negative electrodes of the control end of the electromagnetic relay B (5).

5. The helicopter audio switching circuit according to claim 1, characterized in that: The switch (6) is connected to the positive poles of the control terminals of the electromagnetic relays A and B through permanent connectors A (10) and B (11), respectively, and the negative poles of the control terminals of the electromagnetic relays A and B are connected to the ground of the onboard power supply through permanent connectors C (12) and D (13), respectively.

6. The helicopter audio switching circuit according to claim 1, characterized in that: The electromagnetic relay uses an aviation DC load power supply type electromagnetic relay.

7. The helicopter audio switching circuit according to claim 6, characterized in that: The electromagnetic relay model is J400-D4A.

8. An audio switching method for a helicopter audio switching circuit according to any one of claims 1 to 7, characterized in that: Under normal conditions, the audio of the original device (1) is connected to the intercom system (3) via the normally closed pins of electromagnetic relays A and B. When switching the audio, the switch (6) is closed, the electromagnetic relays A and B are powered on, the normally closed pins are disconnected, and the normally open pins are closed and connected, and the audio of the newly installed device (2) is connected to the intercom system (3) via the normally open pins of electromagnetic relays A and B, completing the audio switching between the original device (1) and the newly installed device (2).

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