Helicopter shock absorbing step

Abstract

The application belongs to the technical field of mechanical design, and discloses a helicopter damping footrest, which comprises an inner cylinder, a medium cylinder, an outer cylinder, a front end fixed sealing plate, a spring assembly, a counterweight assembly, an eccentric cylinder and an eccentric cylinder rotating assembly. The inner cylinder is coaxial with and fixedly connected to the original footrest, the outer cylinder is coaxial with the original footrest, and the outer cylinder is connected to the front end of the inner cylinder through the front end fixed sealing plate. The medium cylinder is sleeved outside the inner cylinder and coaxial with the inner cylinder, a medium cavity is formed between the inner cylinder and the medium cylinder, and the inner cavity is filled with damping medium. The eccentric cylinder is sleeved outside the medium cylinder, and the rotating shaft of the eccentric cylinder is coaxial with the medium cylinder. The counterweight assembly is arranged in the eccentric cylinder, the spring assembly is arranged between the counterweight assembly and the medium cylinder, and the eccentric cylinder rotating assembly is arranged at the rear end of the outer cylinder and connected to the eccentric cylinder to drive the eccentric cylinder to rotate.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of mechanical design, and particularly relates to a helicopter vibration-reducing footrest. BACKGROUND

[0002] The helicopter footrest, also known as a rudder, mainly functions to control the pitch of the tail rotor blades of a helicopter through a control cable system, change the balance state of the torque and counter-torque of the helicopter, and cause the heading of the helicopter to change to the left or right, thereby realizing the change of the forward direction of the helicopter.

[0003] The tail rotor blades of a certain type of helicopter vibrate greatly, and when the vibration of the tail rotor blades is transmitted to the footrest through the hard rod structure of the control cable system, the footrest also vibrates violently at a high frequency, which affects the feet of the pilot. The main solutions are to reduce the vibration level of the tail rotor blades or to use a non-hard structure control cable system, but the research and improvement and economic cost are great, and the implementation difficulty is great. SUMMARY

[0004] The present application aims to provide a helicopter vibration-reducing footrest. By using high-density small-particle bodies such as lead sand to achieve the energy absorption effect of following movement, the first layer of vibration reduction is realized. By using springs with different extension amounts to load weights, different vibration reduction effects can be achieved, and the second layer of vibration reduction is realized. The different vibration reduction effects can be felt and adjusted by the pilot through the footrest, which is scientific and reasonable and provides great convenience for the pilot.

[0005] TECHNICAL SCHEME

[0006] A helicopter vibration-reducing footrest comprises an inner cylinder, a medium cylinder, an outer cylinder, a front-end fixed sealing plate, a spring assembly, a counterweight assembly, an eccentric cylinder, and an eccentric cylinder rotation assembly.

[0007] The inner cylinder is coaxial with and fixedly connected to the original footrest, and the outer cylinder is coaxially arranged with the original footrest. The outer cylinder is connected to the inner cylinder through the front-end fixed sealing plate.

[0008] The medium cylinder is sleeved outside the inner cylinder and coaxial with the inner cylinder, and a medium cavity is formed between the inner cylinder and the medium cylinder, which is filled with a vibration-reducing medium.

[0009] The eccentric cylinder is sleeved outside the medium cylinder, and the rotation axis of the eccentric cylinder is coaxial with the medium cylinder.

[0010] The counterweight assembly is arranged in the eccentric cylinder, and the spring assembly is arranged between the counterweight assembly and the medium cylinder.

[0011] The eccentric cylinder rotation assembly is arranged at the rear end of the outer cylinder and connected to the eccentric cylinder for driving the eccentric cylinder to rotate.

[0012] Further, the eccentric cylinder is a cylinder body with one end open, and the unopened end is provided with an eccentric shaft, which is arranged at the four-sixth division point of the diameter.

[0013] Further, the counterweight assembly comprises a counterweight tube and a counterweight rod;

[0014] The counterweight tube is a cylinder with one end open, which is arranged between the medium cylinder and the eccentric cylinder, and the counterweight rod is placed at the lower end inside the counterweight tube, which rolls in the counterweight tube under the action of gravity; the upper outer side of the counterweight tube is in contact with the inner wall of the eccentric cylinder.

[0015] Further, the spring assembly comprises a spring top plate, a spring bottom plate and a spring group fixed between the two;

[0016] The spring bottom plate is fixed on the outer side wall of the medium cylinder, and the spring top plate is in contact with the inner wall of the counterweight tube;

[0017] When the shorter side of the eccentric tube radius is turned upward, the compression amount of the spring reaches the upper limit, and when the longer side of the eccentric tube radius is turned upward, the compression amount of the spring reaches the lower limit.

[0018] The spring group comprises at least five springs, which are completely identical. Alternatively, the springs have the same length but different elastic coefficients.

[0019] Further, the eccentric cylinder rotating assembly comprises an eccentric cylinder gear, an intermediate pinion, an intermediate gear, an adjusting wheel gear and an adjusting wheel;

[0020] The eccentric cylinder gear is coaxially connected with the eccentric shaft of the eccentric cylinder, the eccentric cylinder gear is engaged with the intermediate pinion, the intermediate pinion is coaxially fixed with the intermediate gear, the intermediate gear is engaged with the adjusting wheel gear; the adjusting wheel gear is coaxially fixed with the adjusting wheel;

[0021] The intermediate gear and the intermediate pinion are hinged on the intermediate gear fixed plate through the intermediate shaft; the adjusting wheel and the adjusting wheel gear are hinged on the adjusting wheel fixed plate through the intermediate shaft.

[0022] Further, the outer cylinder is provided with an annular boss on the side close to the adjusting wheel gear, the diameter of the adjusting wheel is greater than the diameter of the annular boss, and the outer contour of the adjusting wheel is provided with anti-skid lines.

[0023] Further, the outer diameter size of the medium cylinder is 1.5 times the outer diameter size of the inner cylinder, and the damping medium is a high-density particle body of a solid state at room temperature with a density greater than 10 g / cm 3 The diameter is not more than 0.25 nm, and the filling volume of the damping medium is 60% to 90% of the volume of the medium cavity.

[0024] Further, the counterweight tube and the counterweight rod are made of iron, copper, lead, tungsten and other metals with a density greater than 7 g / cm 3 at room temperature in a solid state.

[0025] Furthermore, it also includes: a spring plate sliding mechanism, which is disposed on the inner surface of the front fixed sealing plate and is used to limit the spring top plate, thereby allowing the spring top plate to move radially along the spring plate sliding mechanism.

[0026] Furthermore, the outer diameter of the counterweight tube is 0.6 to 0.7 times the inner diameter of the eccentric cylinder.

[0027] In summary, the beneficial effects of the present invention are as follows:

[0028] (1) This invention uses the energy absorption effect of high-density small particles such as lead sand following the motion to achieve the purpose of the first layer of vibration reduction. Using springs with different extension and loads can produce different vibration reduction effects, thus achieving the purpose of the second layer of vibration reduction. This invention is scientific.

[0029] (2) This invention, through its ingenious internal structure and small structural volume, compactly achieves the energy absorption effect of high-density small particles following motion and the different vibration reduction effects that spring-loaded weights with varying degrees of extension and contraction can produce. The concept is ingenious.

[0030] (3) Through meticulous design, this invention saves a lot of structure, has low manufacturing complexity, simple assembly method, clear and easy-to-understand usage logic, small size and light weight, and good economy.

[0031] (4) The present invention allows the helicopter pilot to feel and adjust different vibration reduction effects by using the foot pedal of the pilot's foot. It is scientific and reasonable, provides great convenience for helicopter pilots, has good human-machine interaction, and is highly practical. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the appearance of a helicopter vibration damping foot pedal.

[0033] Figure 2 This is a cross-sectional view of a helicopter vibration damping pedal. Detailed Implementation

[0034] A helicopter vibration damping foot pedal is composed of: a spring plate sliding mechanism 1, an inner cylinder 2, a medium cylinder 3, a counterweight bar 4, a counterweight tube 5, a connecting bolt 6, a medium cavity 7, an eccentric cylinder gear 8, an adjusting wheel gear 9, an adjusting wheel fixing plate 10, an adjusting wheel 11, a middle large gear 12, a middle gear fixing plate 13, a middle small gear 14, an eccentric cylinder fixing plate 15, an eccentric cylinder 16, a spring 17, a spring base plate 18, a spring top plate 19, an outer cylinder 20, and a front end fixed sealing plate 21.

[0035] System device composition and main functions:

[0036] (1) The damping pedal is a cylindrical structure, the outermost layer is an outer cylinder 20, the innermost layer is an inner cylinder 2, the front end is a front end fixed sealing plate 21, and the rear end is an adjusting wheel 11. The original pedal tail section is screwed into the inner cylinder 2;

[0037] (2) The inner cylinder 2, the medium cylinder 3, the counterweight tube 5, the eccentric cylinder gear 8, the adjusting wheel gear 9, the adjusting wheel fixed plate 10, the adjusting wheel 11, the eccentric cylinder fixed plate 15, the outer cylinder 20, and the front end fixed sealing plate 21 are coaxial with the original pedal tail section;

[0038] (3) The inner diameter of the inner cylinder 2 is equivalent to the outer diameter of the original pedal tail section but slightly larger. The inner side of the inner cylinder 2 is arranged with threads, and the connecting bolt 6 is fixedly connected with the original pedal tail section. The outer side is arranged with threads, and the connecting bolt 6 is threadedly connected with the inner cylinder 2;

[0039] (4) The medium cylinder 3 is fixedly connected at the front end of the front end fixed sealing plate 21. The outer diameter of the medium cylinder 3 is 1.5 times the outer diameter of the inner cylinder 2. The medium cylinder 3 is sleeved on the outer side of the inner cylinder 2. The gap between the medium cylinder 3 and the inner cylinder 2 forms a medium cavity 7. The medium cavity 7 stores high-density small particles such as lead sand. The volume of the stored high-density small particles is required to be four-fifths of the volume of the medium cavity 7. When the pedal vibrates greatly, the high-density small particles follow the movement to absorb energy, achieving the first layer of damping;

[0040] (5) The lower end of the spring 17 is fixedly connected to the spring bottom plate 18, and the upper end is fixedly connected to the spring top plate 19. Under the action of gravity, the spring bottom plate 18 is placed on the top end of the medium cylinder 3. The spring top plate 19 can slide freely in the vertical direction through the spring plate sliding mechanism 1, so that the spring can stretch and contract in the vertical direction. The spring plate sliding mechanism 1 is arranged on the upper half of the front end fixed sealing plate 21, and the front end of the spring top plate 19 is limited at the end of the front end fixed sealing plate 21 in the axial direction of the pedal to prevent axial movement. There are generally not less than 5 groups of springs 17 between the spring bottom plate 18 and the spring top plate 19;

[0041] (6) The counterweight tube 5 is arranged between the eccentric cylinder 16 and the spring top plate 19, with its top end placed on the upper end of the spring top plate 19 and its bottom end placed with a counterweight rod 4. The counterweight tube 5 can cover the structures of the inner cylinder 2, the medium cylinder 3, the spring 17, the spring bottom plate 18, the spring top plate 19, etc. The counterweight tube 5 and the counterweight rod 4 are made of lead or other high-density materials. The large mass of the counterweight tube 5 and the counterweight rod 4 presses the springs 17 of different lengths to achieve the second layer of damping at different vibration frequencies and intensities;

[0042] (7) The eccentric cylinder 16 rotates around the eccentric shaft of its rear end, the eccentric shaft of its rear end is arranged at the four-sixth point of the diameter of the eccentric cylinder 16, when the eccentric cylinder 16 rotates around the eccentric shaft of its rear end, the distance between the upper end of the cylinder wall of the eccentric cylinder 16 and the lower end of the spring 17 changes continuously, so that the length of the spring changes continuously. The eccentric cylinder 16 is hinged to the outer cylinder 20 through the eccentric cylinder fixing plate 15.

[0043] (8) The eccentric shaft rear end of the eccentric cylinder 16 is arranged with the eccentric cylinder gear 8, the eccentric cylinder gear 8 is engaged with the intermediate pinion 14, the intermediate pinion 14 is coaxially fixed with the intermediate gear 12, the intermediate gear 12 is engaged with the adjusting wheel gear 9, the adjusting wheel gear 9 is coaxially fixed with the adjusting wheel 11. The intermediate gear 12 and the intermediate pinion 14 are hinged on the intermediate gear fixing plate 13 through the intermediate shaft. The transmission ratio of the eccentric cylinder gear 8 and the intermediate pinion 14 is 1:2, the transmission ratio of the intermediate gear 12 and the adjusting wheel gear 9 is 3:1, the number of teeth and the diameter of the intermediate gear 12 are twice that of the intermediate pinion 14, therefore, the adjusting wheel 11 rotates 6 circles, the eccentric cylinder 16 rotates 1 circle.

[0044] (9) The adjusting wheel 11 and the adjusting wheel gear 9 are hinged on the adjusting wheel fixing plate 10 through the intermediate shaft, the diameter of the adjusting wheel 11 is slightly larger than the diameter of the boss of the outer cylinder 20, the outer contour of the adjusting wheel 11 is arranged with anti-skid lines, the helicopter pilot adjusts the different damping effects by stepping on and stirring the outer contour of the adjusting wheel 11, so that the adjusting wheel 11 rotates, through the intermediate transmission mechanism, so that the eccentric cylinder 16 rotates, and the extension amount of the spring 17 changes.

[0045] (10) When the footrest vibrates greatly, the counterweight rod 4 and the counterweight tube 5 press on the spring 17 with different extension amounts adjusted by the adjusting wheel 11 through their own weight, which can produce different damping effects. The helicopter pilot feels and adjusts the different damping effects by stepping on and stirring the adjusting wheel 11.

[0046] (11) The front end fixed sealing plate 21 is fixed at the front end of the outer cylinder 20, the adjusting wheel fixing plate 10 is fixed at the rear end of the outer cylinder 20, the wall rear end of the outer cylinder 20 protrudes a ring boss, which prevents the helicopter pilot's foot from accidentally touching the adjusting wheel 11 when the footrest vibrates well.

[0047] System running process

[0048] (1) First, the connecting bolt 6 is coaxially fixed at the last end of the original footrest tail section, the device is screwed into the connecting bolt 6, the connecting bolt 6 is threadedly matched with the inner cylinder 2, so that the arrow mark on the front end fixed sealing plate 21 is vertically upward, as shown in Figure 2 Thus, the assembly of the device on the original footrest tail section is completed.

[0049] (2) When the foot pedal vibrates greatly, the medium cavity 7 contains high-density small particles such as lead sand, which absorb energy as they move, thus achieving the purpose of the first layer of vibration reduction.

[0050] (3) When the vibration of the foot pedal is too great for the helicopter pilot to accept, the helicopter pilot can step on the outer contour of the adjustment wheel 11 with his foot to make the adjustment wheel 11 rotate.

[0051] (4) The adjusting wheel 11 drives the adjusting wheel gear 9 on the same axis. The adjusting wheel gear 9 meshes with the middle large gear 12, which reduces the speed by 3 times. The middle large gear 12 drives the middle small gear 14 on the same axis. The middle small gear 14 meshes with the eccentric cylinder gear 8, which reduces the speed by 2 times. The eccentric cylinder gear 8 drives the eccentric cylinder 16 on the same axis. Therefore, for every 6 rotations of the adjusting wheel 11, the eccentric cylinder 16 rotates 1 rotation.

[0052] (5) The eccentric cylinder 16 rotates, causing the spring 17 to change its extension and contraction.

[0053] (6) When the foot pedal vibrates greatly, the counterweight bar 4 and the counterweight tube 5 press against the springs 17 with different extensions adjusted by the adjusting wheel 11 through their own weight, which can produce different vibration reduction effects. The helicopter pilot can feel and adjust the different vibration reduction effects by stepping on and turning the adjusting wheel 11.

[0054] (1) Inner cylinder 2, medium cylinder 3, counterweight tube 5, eccentric cylinder gear 8, adjusting wheel gear 9, adjusting wheel fixing plate 10, adjusting wheel 11, eccentric cylinder fixing plate 15, outer cylinder 20, and front end fixing sealing plate 21 are all coaxial with the original foot pedal tail section.

[0055] (2) The inner diameter of the inner cylinder 2 is similar to but slightly larger than the outer diameter of the original pedal tail section, and the connecting bolt 6 forms a threaded fit with the inner cylinder 2.

[0056] (3) The outer diameter of the medium cylinder 3 is 1.5 times that of the outer diameter of the inner cylinder 2. The medium cavity 7 stores high-density small particles such as lead sand. The volume of the high-density small particles stored is required to be four-fifths of the volume of the medium cavity 7. When the foot pedal vibrates greatly, the high-density small particles follow the movement and absorb energy, thus achieving the purpose of the first layer of vibration reduction.

[0057] (4) The spring top plate 19 can slide freely in the vertical direction through the spring plate sliding mechanism 1, so that the spring can extend and retract in the vertical direction. The front end of the spring top plate 19 is restricted to the front fixed sealing plate 21 in the axial direction of the pedal to prevent it from moving axially. At least 5 sets of springs 17 are generally arranged between the spring bottom plate 18 and the spring top plate 19;

[0058] (5) Both the counterweight tube 5 and the counterweight rod 4 are made of high-density materials such as lead. The large mass of the counterweight tube 5 and the counterweight rod 4 presses down on the springs 17 at different lengths to achieve the purpose of vibration reduction under different vibration frequencies and intensities in the second layer.

[0059] (6) The eccentric cylinder 16 rotates around the eccentric shaft of its rear end, the eccentric shaft of its rear end is arranged at the four-sixth point of the diameter of the eccentric cylinder 16, when the eccentric cylinder 16 rotates around the eccentric shaft of its rear end, the distance between the upper end of the eccentric cylinder 16 cylinder wall and the lower end of the spring 17 changes continuously, so that the length of the spring changes continuously.

[0060] (7) The eccentric cylinder gear 8 is engaged with the intermediate pinion 14, the intermediate gear 12 is engaged with the adjusting wheel gear 9, the transmission ratio of the eccentric cylinder gear 8 and the intermediate pinion 14 is 1:2, the transmission ratio of the intermediate gear 12 and the adjusting wheel gear 9 is 3:1, the number of teeth and the diameter of the intermediate gear 12 is twice that of the intermediate pinion 14, therefore, the adjusting wheel 11 rotates 6 circles, the eccentric cylinder 16 rotates 1 circle.

[0061] (8) The diameter of the adjusting wheel 11 is slightly larger than the diameter of the boss of the outer cylinder 20, the outer contour of the adjusting wheel 11 is arranged with anti-skid lines, the helicopter pilot adjusts the different damping effects by stepping on and turning the outer contour of the adjusting wheel 11, through the intermediate transmission mechanism, the eccentric cylinder 16 rotates, and the extension and retraction amount of the spring 17 changes.

[0062] (9) When the foot pedal vibration is large, the counterweight rod 4 and the counterweight tube 5 press on the spring 17 with different extension and retraction amounts adjusted by the adjusting wheel 11 through its own weight, which can produce different damping effects. The helicopter pilot feels and adjusts the different damping effects by stepping on and turning the adjusting wheel 11.

Claims

1. A helicopter vibration-damping foot pedal, characterized in that: The vibration-damping foot pedal includes: an inner cylinder, a medium cylinder, an outer cylinder, a front fixed sealing plate, a spring assembly, a counterweight assembly, an eccentric cylinder, and an eccentric cylinder rotating assembly; The inner cylinder is coaxial with and fixedly connected to the foot pedal, the outer cylinder is coaxial with the foot pedal, and the front end of the outer cylinder is connected to the front end of the inner cylinder through a front end fixed sealing plate. The medium sleeve is installed outside the inner cylinder and is coaxial with the inner cylinder. A medium cavity is formed between the inner cylinder and the medium sleeve, which is filled with vibration damping medium. An eccentric cylinder is sleeved on the outside of the medium cylinder, and the rotation axis of the eccentric cylinder is coaxial with that of the medium cylinder; A counterweight assembly is installed inside the eccentric cylinder, and a spring assembly is installed between the counterweight assembly and the medium cylinder. The eccentric cylinder rotation assembly is located at the rear end of the outer cylinder and is connected to the eccentric cylinder to drive the eccentric cylinder to rotate. The counterweight assembly includes: a counterweight tube and a counterweight bar; The counterweight tube is a cylinder with one end open, which is set between the medium cylinder and the eccentric cylinder. A counterweight bar is placed at the lower end of the counterweight tube, and the counterweight bar rolls inside the counterweight tube under the action of gravity. The upper outer side of the counterweight tube is in contact with the inner wall of the eccentric cylinder. The spring assembly includes: a spring top plate, a spring bottom plate, and a spring assembly fixed between the two; The spring base plate is fixed to the outer wall of the medium cylinder, and the spring top plate is in contact with the inner wall of the counterweight tube. When the side with the shorter radius of the eccentric tube rotates to the top, the spring is compressed to its upper limit; when the side with the longer radius of the eccentric tube rotates to the top, the spring is compressed to its lower limit. The spring assembly consists of at least five springs.

2. The helicopter vibration-damping foot pedal according to claim 1, characterized in that: An eccentric cylinder is a cylinder with one open end and an eccentric shaft at the closed end. The eccentric shaft is located at the 4 / 6 division point of the diameter.

3. The helicopter vibration-damping foot pedal according to claim 2, characterized in that: The springs are exactly the same, or the springs are the same length but have different spring constants.

4. The helicopter vibration-damping foot pedal according to claim 3, characterized in that: The eccentric cylinder rotating assembly includes: an eccentric cylinder gear, a small intermediate gear, a large intermediate gear, an adjusting wheel gear, and an adjusting wheel; The eccentric cylinder gear is coaxially connected to the eccentric shaft of the eccentric cylinder, the eccentric cylinder gear meshes with the intermediate small gear, the intermediate small gear is coaxially fixed to the intermediate large gear, the intermediate large gear meshes with the adjusting wheel gear, and the adjusting wheel gear is coaxially fixed to the adjusting wheel. The large intermediate gear and the small intermediate gear are hinged to the intermediate gear fixing plate via the intermediate shaft; the adjusting wheel and the adjusting wheel gear are hinged to the adjusting wheel fixing plate via the intermediate shaft.

5. The helicopter vibration-damping foot pedal according to claim 4, characterized in that: The outer cylinder has an annular boss on the side near the adjusting wheel gear. The diameter of the adjusting wheel is larger than the diameter of the annular boss, and the outer contour of the adjusting wheel is decorated with anti-slip texture.

6. The helicopter vibration-damping foot pedal according to claim 5, characterized in that: The outer diameter of the medium cylinder is 1.5 times the outer diameter of the inner cylinder, and the damping medium has a density greater than 10 g / cm³. 3 The material is a room-temperature solid high-density particle with a diameter not exceeding 0.25nm, and the vibration damping medium filling volume is 60%~90% of the medium cavity volume.

7. The helicopter vibration-damping foot pedal according to claim 6, characterized in that: The counterweight tube and counterweight bar are made of a material with a density greater than 7 g / cm³. 3 Solid metal at room temperature.

8. The helicopter vibration-damping foot pedal according to claim 6, characterized in that: Also includes: The spring plate sliding mechanism is located on the inner surface of the front fixed sealing plate and is used to limit the spring top plate, thereby allowing the spring top plate to move radially along the spring plate sliding mechanism.

9. The helicopter vibration-damping foot pedal according to claim 6, characterized in that: The outer diameter of the counterweight tube is 0.6 to 0.7 times the inner diameter of the eccentric cylinder.

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