A diesel engine for a drone

Abstract

This invention discloses a diesel engine for unmanned aerial vehicles (UAVs), relating to the field of UAV diesel engine technology. It includes a frame, with the diesel engine body installed inside the frame. Two sets of extension plates are installed on both sides of the frame, and rotating propellers are installed on the upper surfaces of both sets of extension plates. A resonance cancellation mechanism that converts landing force into meshing force is installed on the lower surface of the frame. A counting mechanism that converts landing force into contact force is installed at the power output end of the resonance cancellation mechanism. By setting the resonance cancellation mechanism, when the UAV lands on a hard landing or a rough runway, the landing impact force is transmitted to the rack through the landing gear and the receiving block. This causes the rack to slide inside the receiving block and drive the gear to rotate, thereby causing the connecting ring, the receiving frame, and the mass block to swing. Simultaneously, the torsion spring is twisted to store energy, which can couple the high-frequency vibration from the landing gear with the low-frequency vibration of the diesel engine body itself to generate beat frequency energy.

Description

Technical Field

[0001] This invention relates to the field of diesel engine technology for unmanned aerial vehicles (UAVs), specifically to a diesel engine for UAVs. Background Technology

[0002] Unmanned aerial vehicles (UAVs) are aircraft that fly remotely or autonomously without a crew. They are widely used in aerial surveying, agricultural plant protection, logistics transportation, emergency rescue, and military reconnaissance. The diesel engines used in UAVs are usually lightweight, high power-to-weight ratio optimized special heavy oil engines that can directly use aviation kerosene or diesel fuel. Compared to automotive diesel engines, they need to solve special challenges such as high-altitude low-temperature starting, vibration suppression, and heat dissipation, and often adopt high-pressure common rail injection, horizontally opposed or twin opposed piston configurations.

[0003] In existing UAV diesel engines, the intake stroke draws in pure air, the compression stroke compresses the air to high pressure and high temperature, and then during the fuel injection and power strokes, the high-pressure common rail fuel injection system atomizes the diesel fuel and injects it into the cylinder before the top dead center of the compression stroke. The fuel ignites spontaneously and pushes the piston downward to do work. The exhaust stroke discharges the exhaust gas after combustion. The electronic control unit precisely controls the fuel injection quantity and injection timing based on parameters such as flight altitude, speed, and intake pressure. At the same time, it works with the exhaust gas turbocharger to maintain the intake air density at high altitudes, and the cylinder temperature is controlled by a liquid cooling or air cooling system, thereby ensuring that the UAV outputs stable power under different flight conditions.

[0004] However, when a drone makes a hard landing or lands on a rough runway, the high-frequency vibration from the landing gear couples with the low-frequency vibration of the diesel engine itself, producing a beat frequency effect. The engine's rubber damping pads are crushed, the metal fixing bolts are repeatedly stretched and broken, the engine shifts on the frame, and the throttle cable or oil pipe is damaged, which improves the safety of actual operation and use.

[0005] Although the problem during landing can be resolved, ground crew cannot determine whether the resonance during landing is severe enough to require maintenance. Without a record, potential hazards may be overlooked, leading to the same batch of bolts accumulating damage multiple times and suddenly breaking during subsequent flights. Instead, the illusion that the problem has been solved reduces maintenance vigilance, causing safety to decrease rather than increase. Summary of the Invention

[0006] The purpose of this invention is to provide a diesel engine for unmanned aerial vehicles (UAVs) to solve the resonance problem during landing and how to record the resonance.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a diesel engine for an unmanned aerial vehicle (UAV), comprising a frame, wherein a diesel engine body is installed inside the frame, two sets of extension plates are installed on both sides of the frame, a rotating propeller is installed on the upper surface of each of the two sets of extension plates, a resonance cancellation mechanism for converting descent force into meshing force is installed on the lower surface of the frame, and a counting mechanism for converting descent force into contact force is installed at the power output end of the resonance cancellation mechanism.

[0008] Preferably, the resonance cancellation mechanism includes a connecting block, a rack, a receiving block, an L-shaped plate, a connecting rod, and a gear. The upper surface of the connecting block is fixedly installed with the lower surface of the frame, the upper surface of the rack is fixedly installed with the lower surface of the connecting block, the interior of the receiving block is slidably connected with the outer surface of the rack, a rectangular groove is provided on one side of the receiving block, the back of the L-shaped plate is fixedly installed with the front of the receiving block, the outer surface of the connecting rod is rotatably installed with the inner wall of the L-shaped plate, and the interior of the gear is fixedly installed with the outer surface of the connecting rod.

[0009] Preferably, the counting mechanism includes a rectangular block, a touch rod, and a touch counter. The rectangular block is installed below the frame and does not directly contact the lower surface of the frame. The upper surface of the touch rod is fixedly installed to the lower surface of the rectangular block. The upper surface of the touch counter is installed opposite to the bottom end of the touch rod. When the resonance force is too large, the touch rod and the touch counter directly contact each other.

[0010] Preferably, a fixing plate is fixedly installed on the back of the receiving block, and the interior of the fixing plate is rotatably installed on the outer surface of the connecting rod.

[0011] Preferably, a connecting ring is fixedly installed on the outer surface of the connecting rod, a receiving frame is fixedly installed on the outer surface of the connecting ring, and a mass block is fixedly installed on the lower surface of the receiving frame.

[0012] Preferably, a torsion spring is fixedly installed on the back of the L-shaped plate, and one end of the torsion spring is fixedly installed to the right side of the connecting ring.

[0013] Preferably, a connecting spring is fixedly installed at the bottom of the rack, and a telescopic rod is fixedly installed at the bottom of the rack.

[0014] Preferably, one end of the connecting spring is fixedly installed to the bottom end inside the receiving block, and one end of the telescopic rod is fixedly installed to the bottom end inside the receiving block.

[0015] Preferably, a landing gear is fixedly installed on the right side of the receiving block, and a placement pad is fixedly installed on the bottom of the landing gear.

[0016] Preferably, a sliding groove is provided inside one side of the receiving block, the inner wall of the sliding groove is slidably connected to the outer surface of the rectangular block, and one side of the receiving block is fixedly installed with one side of the touch counter.

[0017] Compared with the prior art, the beneficial effects of the present invention are: This invention incorporates a resonance cancellation mechanism. When the UAV lands on a hard landing or a rough runway, the impact force is transmitted to the rack through the landing gear and the receiving block. This causes the rack to slide inside the receiving block and drive the gear to rotate, which in turn causes the connecting ring, the receiving frame, and the mass block to swing. Simultaneously, the torsion spring is twisted to store energy. This converts the beat frequency energy generated by the coupling of the high-frequency vibration from the landing gear and the low-frequency vibration of the diesel engine itself into the mechanical swing kinetic energy of the mass block and the elastic potential energy of the torsion spring. This effectively consumes harmful vibration energy and prevents the vibration from directly impacting the rubber damping pads and metal fixing bolts between the frame and the diesel engine. Compared with the prior art that relies solely on the passive vibration isolation of rubber damping pads, this invention can prevent the engine from shifting on the frame, damaging the throttle cable or oil pipes, and significantly improves the operational safety of the UAV during landing.

[0018] This invention employs a counting mechanism that, while the resonance cancellation mechanism is operating, utilizes the sliding stroke of a rack to drive a rectangular block and a touch rod. When the landing resonance force is excessive and exceeds a preset safety threshold, the bottom end of the touch rod directly contacts a touch-type counter, recording a severe resonance event each time it is triggered. The touch-type counter is a purely mechanical counting device, requiring no power supply and unaffected by vibration or electromagnetic interference. It automatically accumulates the number of resonances during landing. After landing, ground personnel can accurately determine whether a dangerous level of resonance occurred and its severity by directly reading the touch-type counter's value. This avoids the misconception that the problem has been resolved, leading to reduced maintenance vigilance and a potential decrease in safety. It provides reliable data for UAV ground maintenance, effectively ensuring the safety of subsequent flights. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 For the present invention Figure 1 A top-view structural diagram; Figure 3 For the present invention Figure 1 A schematic diagram of the structure viewed from below; Figure 4 For the present invention Figure 1 A schematic diagram of the side view structure; Figure 5 For the present invention Figure 1 A schematic diagram of the cross-sectional structure; Figure 6 For the present invention Figure 5 Enlarged schematic diagram of the structure at point A; Figure 7 For the present invention Figure 5 A schematic diagram of the side view structure; Figure 8 For the present invention Figure 7 Enlarged schematic diagram of the structure at point B.

[0020] In the diagram: 1. Frame; 2. Diesel engine body; 3. Extension plate; 4. Rotating propeller; 5. Resonance cancellation mechanism; 51. Connecting block; 52. Rack; 53. Support block; 54. Rectangular groove; 55. L-shaped plate; 56. Connecting rod; 57. Fixing plate; 58. Gear; 59. Torsion spring; 510. Connecting ring; 511. Support frame; 512. Mass block; 513. Connecting spring; 514. Telescopic rod; 6. Landing gear; 7. Placement pad; 8. Counting mechanism; 81. Sliding groove; 82. Rectangular block; 83. Touch rod; 84. Touch counter. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Please see Figure 1 , Figure 5 Figure 6As shown, the present invention provides a technical solution: a diesel engine for a drone, including a frame 1, a diesel engine body 2 installed inside the frame 1, two sets of extension plates 3 installed on both sides of the frame 1, a rotating propeller 4 installed on the upper surface of each of the two sets of extension plates 3, a resonance cancellation mechanism 5 for converting descent force into meshing force installed on the lower surface of the frame 1, a counting mechanism 8 for converting descent force into contact force installed at the power output end of the resonance cancellation mechanism 5, the resonance cancellation mechanism 5 including a connecting block 51, a rack 52, a receiving block 53, an L-shaped plate 55, a connecting rod 56 and a gear 58, the upper surface of the connecting block 51 is fixedly installed with the lower surface of the frame 1, the upper surface of the rack 52 is fixedly installed with the lower surface of the connecting block 51, the interior of the receiving block 53 is slidably connected with the outer surface of the rack 52, a rectangular groove 54 is formed on one side of the receiving block 53, and the back of the L-shaped plate 55 is connected with... The front of the receiving block 53 is fixedly installed. The outer surface of the connecting rod 56 is rotatably installed with the inner wall of the L-shaped plate 55. The inside of the gear 58 is fixedly installed with the outer surface of the connecting rod 56. A fixing plate 57 is fixedly installed on the back of the receiving block 53. The inside of the fixing plate 57 is rotatably installed with the outer surface of the connecting rod 56. A connecting ring 510 is fixedly installed on the outer surface of the connecting ring 510. A receiving frame 511 is fixedly installed on the outer surface of the connecting ring 510. A mass block 512 is fixedly installed on the lower surface of the receiving frame 511. A torsion spring 59 is fixedly installed on the back of the L-shaped plate 55. One end of the torsion spring 59 is fixedly installed with the right side of the connecting ring 510. A connecting spring 513 is fixedly installed at the bottom of the rack 52. A telescopic rod 514 is fixedly installed at the bottom of the rack 52. One end of the connecting spring 513 is fixedly installed with the bottom inside the receiving block 53. One end of the telescopic rod 514 is fixedly installed with the bottom inside the receiving block 53.

[0023] Specifically, through the resonance cancellation mechanism 5, when the UAV lands, the vertical landing force borne by the frame 1 is transmitted to the rack 52 through the connecting block 51. The receiving block 53 slides on the outer surface of the rack 52 and converts the vertical landing force into the meshing force between the rack 52 and the gear 58, realizing the conversion of force direction. This effectively reduces the impact damage to the diesel engine body 2 at the moment of landing. At the same time, the cooperation between the connecting spring 513 and the telescopic rod 514 provides elastic restoring force to the receiving block 53, further absorbing the landing impact energy and improving the stability and safety of the landing process. The mass block 512 is mounted on the connecting rod 56 via the support frame 511 and the connecting ring 510. When the UAV vibrates during flight or landing, the mass block 512 swings in the opposite direction under the action of gravity and inertia. Combined with the elastic recovery of the torsion spring 59, it forms a resonance cancellation effect, effectively suppressing the vibration amplitude of the frame 1, thereby protecting the diesel engine body 2 installed inside the frame 1 from resonance damage and extending the service life of the diesel engine.

[0024] according to Figure 1 , Figure 7 and Figure 8 As shown, the counting mechanism 8 includes a rectangular block 82, a touch rod 83, and a touch counter 84. The rectangular block 82 is installed below the frame 1 and does not directly contact the lower surface of the frame 1. The upper surface of the touch rod 83 is fixedly installed with the lower surface of the rectangular block 82. The upper surface of the touch counter 84 is installed opposite to the bottom end of the touch rod 83. When the resonance force is too large, the touch rod 83 and the touch counter 84 directly contact each other. A sliding groove 81 is provided inside one side of the receiving block 53. The inner wall of the sliding groove 81 is slidably connected with the outer surface of the rectangular block 82. One side of the receiving block 53 is fixedly installed with one side of the touch counter 84.

[0025] Specifically, through the setting of the counting mechanism 8, when the drone lands, the receiving block 53 in the resonance cancellation mechanism 5 slides on the rack 52 and drives the rectangular block 82 downward through the sliding groove 81, thereby causing the touch rod 83 to move downward. When the landing impact force exceeds the set threshold, the touch rod 83 directly contacts the touch counter 84 and triggers the counting action. This realizes the accurate conversion of the impact force of each landing into a recordable counting signal. It does not require external power supply, has a simple structure, and is accurate and reliable in counting. It is convenient for operators to keep track of the number of drone landings in real time, and provides accurate data for the maintenance cycle of the diesel engine body 2. The rectangular block 82 is installed below the frame 1 and does not directly contact the lower surface of the frame 1. This gap design effectively avoids the touch rod 83 from accidentally contacting the touch counter 84 due to slight vibration or airflow disturbance during normal flight of the UAV. It ensures that counting will only be triggered when a sufficiently large resonant impact force is generated during landing, which greatly improves the accuracy and reliability of counting and prevents maintenance judgment errors due to miscounting.

[0026] according to Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, a landing gear 6 is fixedly installed on the right side of the receiving block 53, and a placement pad 7 is fixedly installed on the bottom of the landing gear 6.

[0027] Specifically, the landing gear 6, fixedly installed on the right side of the receiving block 53, provides a dedicated support structure for the drone when parking or landing on the ground. This prevents the drone's fuselage from directly contacting the ground, effectively preventing wear or scratches to the drone's bottom caused by sand, water, or uneven ground. At the same time, the placement pad 7 fixedly installed at the bottom of the landing gear 6 further increases the contact area with the ground, reducing the overall pressure of the drone on the ground, enabling the drone to land and park smoothly in various terrain conditions. The placement pad 7 is usually made of elastic material. When the drone lands, the placement pad 7 acts as the first buffer layer to contact the ground. It can effectively absorb and disperse the vertical impact force generated at the moment of landing, and prevent the hard impact force from being directly transmitted to the diesel engine body 2 inside the frame 1 through the landing gear 6 and the receiving block 53. Together with the resonance cancellation mechanism 5, it forms a double buffer protection system, which greatly extends the service life of the diesel engine body 2 and its internal precision components.

[0028] The overall mechanism achieves the following effect: when the UAV completes its flight mission and lands, the placement pad 7 at the bottom of the landing gear 6 makes contact with the ground first. During a hard landing or landing on a rough runway, the ground reaction force is transmitted to the receiving block 53 through the landing gear 6. At this time, the frame 1 and the diesel engine body 2 installed inside it continue to move downward due to inertia, causing the connecting block 51, which is fixedly installed on the lower surface of the frame 1, to drive the rack 52 to slide downward inside the receiving block 53. When the rack 52 slides downward, the gear 58 meshing with it is forced to rotate. The gear 58 is fixedly installed on the connecting rod 56, and the two ends of the connecting rod 56 are rotatably supported by the L-shaped plate 55 and the fixed plate 57, respectively. When the gear 58 rotates, the connecting rod 56 synchronously drives the connecting ring 510 to rotate, which in turn drives the receiving frame 511 and the mass block 512 fixed on its lower surface to produce a deflection motion. The torsion spring 59 installed between the back of the L-shaped plate 55 and the right side of the connecting ring 510 is twisted and stores elastic potential energy. The essential function of this mechanism is that the inertial oscillation of the mass block 512 and the elastic restoring force of the torsion spring 59 together form a dynamic vibration absorber. When the high-frequency vibration transmitted from the landing gear couples with the low-frequency vibration of the diesel engine body 2 to produce a beat frequency effect, the dynamic vibration absorber can absorb the vibration energy of a specific frequency and convert it into the mechanical oscillation of the mass block 512 and the elastic deformation energy of the torsion spring 59, thereby preventing the vibration energy from directly impacting the rubber damping pads and metal fixing bolts between the frame 1 and the diesel engine body 2. The connecting spring 513 and the telescopic rod 514 installed at the bottom of the rack 52 are fixedly installed inside the bottom of the receiving block 53. The connecting spring 513 provides a restoring force to ensure that the rack 52 returns to its initial position after landing; the telescopic rod 514 ensures that the rack 52 maintains linear motion during sliding to prevent jamming. While the resonance cancellation mechanism 5 is working, the counting mechanism 8 simultaneously judges and records the resonance intensity. When the landing resonance force is small, the sliding stroke of the rack 52 inside the receiving block 53 is short, the angular displacement of the gear 58 and related transmission components is small, and the rectangular block 82, which is slidably connected to the sliding groove 81 on one side of the receiving block 53, and the touch rod 83 below it will not touch the touch counter. 84. When the landing resonance force is too large, i.e., the severity of ground resonance exceeds the preset safety threshold, the sliding stroke of rack 52 increases. Through meshing transmission, the downward movement of rectangular block 82 increases, and the bottom end of touch rod 83 directly contacts the upper surface of touch counter 84. Finally, after the UAV takes off, the placement pad 7 and landing gear 6 are no longer subject to ground reaction force. Connecting spring 513 pushes rack 52 to slide upward and reset, and torsion spring 59 releases elastic potential energy to return mass block 512 and connecting ring 510 to their initial positions. At the same time, touch rod 83 separates from touch counter 84. The entire mechanism returns to standby state, ready to deal with the resonance impact that may occur during the next landing.

[0029] The specific configuration of the touch counter 84 can be a purely mechanical step-by-step counter, and the rack 52 and gear 58 should be made of alloy steel and subjected to carburizing and quenching treatment to ensure wear resistance and fatigue resistance under high-frequency reciprocating motion; the torsion spring 59 should be made of piano wire or chromium-silicon alloy steel and be shot peened to extend its fatigue life under repeated torsional conditions.

[0030] During use, after each flight mission lands, ground crew must first read the number of the touch counter 84. If the count exceeds the threshold, the corresponding parts must be replaced, and the rubber shock-absorbing pads and fixing bolts between the frame 1 and the diesel engine body 2 must be checked. Even if there is no visible damage, do not continue to use it.

[0031] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A diesel engine for use in unmanned aerial vehicles (UAVs), characterized in that: The system includes a frame (1), inside which a diesel engine body (2) is installed. Two sets of extension plates (3) are installed on both sides of the frame (1). Rotary propellers (4) are installed on the upper surfaces of the two sets of extension plates (3). A resonance cancellation mechanism (5) that converts the descent force into a meshing force is installed on the lower surface of the frame (1). A counting mechanism (8) that converts the descent force into a contact force is installed at the power output end of the resonance cancellation mechanism (5).

2. A diesel engine for an unmanned aerial vehicle according to claim 1, characterized in that: The resonance cancellation mechanism (5) includes a connecting block (51), a rack (52), a receiving block (53), an L-shaped plate (55), a connecting rod (56), and a gear (58). The upper surface of the connecting block (51) is fixedly installed with the lower surface of the frame (1). The upper surface of the rack (52) is fixedly installed with the lower surface of the connecting block (51). The interior of the receiving block (53) is slidably connected with the outer surface of the rack (52). A rectangular groove (54) is provided on one side of the receiving block (53). The back of the L-shaped plate (55) is fixedly installed with the front of the receiving block (53). The outer surface of the connecting rod (56) is rotatably installed with the inner wall of the L-shaped plate (55). The interior of the gear (58) is fixedly installed with the outer surface of the connecting rod (56).

3. A diesel engine for an unmanned aerial vehicle according to claim 1, characterized in that: The counting mechanism (8) includes a rectangular block (82), a touch rod (83), and a touch counter (84). The rectangular block (82) is installed below the frame (1) and does not directly contact the lower surface of the frame (1). The upper surface of the touch rod (83) is fixedly installed with the lower surface of the rectangular block (82). The upper surface of the touch counter (84) is installed opposite to the bottom end of the touch rod (83). When the resonance force is too large, the touch rod (83) and the touch counter (84) directly contact each other.

4. A diesel engine for an unmanned aerial vehicle according to claim 2, characterized in that: A fixing plate (57) is fixedly installed on the back of the receiving block (53), and the interior of the fixing plate (57) is rotatably installed on the outer surface of the connecting rod (56).

5. A diesel engine for an unmanned aerial vehicle according to claim 2, characterized in that: A connecting ring (510) is fixedly installed on the outer surface of the connecting rod (56), a support frame (511) is fixedly installed on the outer surface of the connecting ring (510), and a mass block (512) is fixedly installed on the lower surface of the support frame (511).

6. A diesel engine for an unmanned aerial vehicle according to claim 2, characterized in that: A torsion spring (59) is fixedly installed on the back of the L-shaped plate (55), and one end of the torsion spring (59) is fixedly installed on the right side of the connecting ring (510).

7. A diesel engine for an unmanned aerial vehicle according to claim 2, characterized in that: A connecting spring (513) is fixedly installed at the bottom of the rack (52), and a telescopic rod (514) is fixedly installed at the bottom of the rack (52).

8. A diesel engine for an unmanned aerial vehicle according to claim 7, characterized in that: One end of the connecting spring (513) is fixedly installed inside the bottom of the receiving block (53), and one end of the telescopic rod (514) is fixedly installed inside the bottom of the receiving block (53).

9. A diesel engine for an unmanned aerial vehicle according to claim 2, characterized in that: A landing gear (6) is fixedly installed on the right side of the receiving block (53), and a placement pad (7) is fixedly installed on the bottom of the landing gear (6).

10. A diesel engine for an unmanned aerial vehicle according to claim 2, characterized in that: A sliding groove (81) is provided inside one side of the receiving block (53). The inner wall of the sliding groove (81) is slidably connected to the outer surface of the rectangular block (82). One side of the receiving block (53) is fixedly installed on one side of the touch counter (84).

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