Helicopter transfer function test suspension method and apparatus

Abstract

The present application belongs to the technical field of helicopter full machine transfer function test suspension design, and discloses a helicopter transfer function test suspension method and device, which comprises the following steps: preparing a rigid annular hanging disc with a plurality of retaining holes, wherein the retaining holes are at least three and are uniformly distributed on the hanging disc; using flexible hangers to pass through the retaining holes and form a rope sleeve connection with the hanging disc, and keeping the hanging disc in a horizontal state after all the hanger connections are completed; connecting a rigid hook to each of the above rope sleeves; using a flexible bandage to be tied to the hub central piece support arm at one end and connected to the hook at the other end, and keeping the hanging disc in a horizontal state after all the bandage connections are completed. The present application solves the problem that the existing suspension technology is prone to causing fatigue or deformation of the suspension disc structure, avoids reserving an exciter excitation loading space at the hub center position to implement hub center excitation loading work, and has the effects of simplicity, safety and stability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of helicopter full machine transfer function test suspension design, and particularly relates to a helicopter transfer function test suspension method and device which avoids the conflict between the suspension position and the excitation loading device and avoids the position of the hub center. BACKGROUND

[0002] From the helicopter model development to the design finalization stage, three major dynamic characteristic tests need to be performed on the full machine to verify whether the machine body structure dynamics design is reasonable, and the dynamics design is optimized and improved through the test results. Among them, the transfer function test technology is the most complex technology. It needs to realize the flexible suspension of the full machine, and the suspension position needs to avoid the hub center position to avoid the conflict with the excitation point. In addition, the safety of the helicopter, the test state conditions and the like need to be ensured.

[0003] At present, there is no related technical research on the test device which is specially used for the transfer function test, suspends the hub center of the helicopter and excites and loads at the hub center. There is no specific test implementation method. The present application is specially used for the helicopter full machine transfer function test. The functions are as follows:

[0004] 1. The free state of the helicopter can be simulated.

[0005] 2. Different loading modes of the excitation source can be realized.

[0006] 3. The helicopter suspension method which needs to avoid the hub center is suitable.

[0007] So far, there is no similar suspension method which needs to avoid the hub center position in China, and no relevant public documents are found in foreign countries.

[0008] The traditional suspension system directly acts the load on the suspension disc body, so that the disc bears the vertical tension, which easily causes structural fatigue or deformation. In addition, the uneven force of multiple hangers will cause the system to shake, affecting the stability. The existing technology lacks reserved space for vertical excitation loading, which limits its application in precise test scenarios.

[0009] The present application provides a suspension method and device which avoids the hub center position to reserve the excitation loading space of the exciter to implement the hub center excitation loading work, and has the effects of simplicity, safety and stability. SUMMARY

[0010] The present application aims at the problem that the traditional suspension system usually directly acts the load on the suspension disc, causing the disc to bear vertical tension and easily causing structural fatigue or deformation, and proposes a suspension method and device which can avoid the load position at the center of the hub and suspend the helicopter hub center, optimizes the force transmission path, causes the disc to only bear radial pressure and avoid bearing the relatively larger vertical tension of the suspension, ensures uniform stress of multiple hangers and improves the system stability.

[0011] The technical scheme of the present application is implemented as follows:

[0012] In the first aspect, the present application discloses a helicopter transfer function test suspension method, which comprises the following steps:

[0013] A rigid annular hanger disc with a plurality of mooring holes is prepared, wherein the mooring holes are at least 3 and uniformly distributed on the hanger disc;

[0014] Flexible hangers are used to pass through the mooring holes and form a rope sleeve connection with the hanger disc, and the hanger disc needs to be kept in a horizontal state after all the hangers are connected;

[0015] A rigid hook is connected to each of the above rope sleeves;

[0016] A flexible strap is used, one end of which is tied to the hub central part support arm, and the other end is connected to the hook, and the hanger disc needs to be kept in a horizontal state after all the straps are connected.

[0017] As a further scheme of the present application: the hanger disc material is high-strength metal, provided with 5 uniformly distributed mooring holes, and the edges of the mooring holes are treated with curved surface smoothing;

[0018] The hangers are made of one or more of flexible steel cables, carbon fiber ropes and nylon cloth woven ropes, one end of the hanger is made into a rope sleeve knot, and the hanger passes through the mooring hole and then passes through the above rope sleeve knot, thereby forming a rope sleeve connection with the hanger disc;

[0019] The hook is designed in one piece or in two pieces; when designed in one piece, one end is provided with a hanging hole and the other end is provided with a hook, and the hook is sleeved on the hanger through the hanging hole; when designed in two pieces, it comprises a damping buffer and two hooks symmetrically arranged and connected at both ends of the damping buffer, and one of the hooks is hung on the rope sleeve of the hanger;

[0020] The strap is a high-toughness nylon rope or cloth woven rope; it is folded in half, one end is hung on the hook, and the other end is tied to the hub central part support arm; or one end is connected to the hook in a rope sleeve connection, and the other end is tied to the hub central part support arm.

[0021] As a further solution of the present invention, the strap and the sling are connected by a hook, and a safety rope is provided between the strap and the sling for connecting the strap and the sling when the hook breaks.

[0022] In a second aspect, the present invention discloses a helicopter transfer function test suspension device, comprising:

[0023] The hanging plate adopts a ring-shaped design and has five mooring holes evenly arranged on the hanging plate;

[0024] The hanging part is a flexible part with the same number as the mooring holes, one end of which passes through the mooring hole to form a rope loop connection with the hanging plate;

[0025] The hook is a rigid part connected to the hanging rope loop;

[0026] The strap is a flexible piece, one end of which is tied to the support arm of the central piece of the hub, and the other end is connected to the hook.

[0027] As a further solution of the present invention: 5 mooring holes are evenly opened on the hanging plate, and the edges of the mooring holes need to be processed to smooth the curved surface.

[0028] As a further solution of the present invention: the sling is made of one or more of a flexible steel cable, a carbon fiber rope, and a nylon cloth woven rope, and one end of the sling is made into a rope loop. After the sling passes through the mooring hole, it passes through the above-mentioned rope loop knot to form a rope loop connection with the hanging plate.

[0029] As a further solution of the present invention: a hanging hole is provided at one end of the hook, and a hook is provided at the other end, and the hook is sleeved on the hook through the hanging hole.

[0030] As a further solution of the present invention: the hook adopts a split design, including a damping buffer and two symmetrically arranged hooks respectively connected to the two ends of the damping buffer, one of the hooks is hung on the hanging rope loop.

[0031] As a further solution of the present invention: the strap is a high-toughness nylon rope or a woven cloth rope, which is folded in half, with one end hung on the hook and the other end tied to the support arm of the central part of the hub; or one end is connected to the hook to form a rope loop, and the other end is tied to the support arm of the central part of the hub.

[0032] As a further solution of the present invention, a safety rope is provided between the strap and the sling, which is used to connect the strap and the sling when the hook breaks.

[0033] The beneficial effects of this application are:

[0034] 1. The application can simulate the suspension state of a helicopter; can implement excitation loading work at the hub center; and can be used for vertical excitation loading work at the hub center of helicopters of different types and tonnage.

[0035] 2. The application can implement vertical excitation loading work at the hub center of a helicopter, and can also implement suspension work at the hub center. The suspension work of the helicopter full-machine transfer function test can be realized by the scheme, and the transfer function from the hub center of the helicopter to each concerned part is measured, thereby providing test basis for vibration analysis, vibration control and structure layout of the helicopter.

[0036] 3. The application has a prolonged structural life: the disc stress mode is optimized, alternating vertical stress is avoided, and fatigue life is improved.

[0037] 4. The application has enhanced dynamic stability: the hanging self-adaptive adjustment capability makes the system still stable under impact load, and the amplitude is reduced.

[0038] 5. The application has high function integration: the reserved excitation loading space and other standardized interfaces support rapid integration and replacement of excitation loading devices.

[0039] 6. The application is convenient to maintain: the quick-release binding belt and the modular hook design facilitate replacement of parts and on-site debugging.

[0040] 7. The application adopts decoupling design: the hook has no direct contact with the hanging disc, and directly contacts with the hanging, thereby completely isolating the influence of vertical tension on the hanging disc.

[0041] 8. The application can be modularly extended: the outer diameter of the hanging disc can be designed as a standardized size, supporting multiple disc series connection or parallel connection, and being suitable for different load scale requirements.

[0042] 9. The application adopts redundancy protection design: the tie-in hole is rounded or embedded with a wear-resistant bushing to prevent friction wear of the hanging; a hook and a safety rope double-layer protection device are arranged between the hanging and the binding belt, and when the hook breaks, the safety rope can play a connecting role to prevent the hanging and the binding belt from being separated.

[0043] The application will be further described in detail in combination with the accompanying drawings of the embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 is a schematic view of a helicopter transfer function test suspension device.

[0045] In the drawing, the reference signs are as follows: 1, hanging; 2, hanging disc; 3, hook; 4, binding belt. DETAILED DESCRIPTION

[0046] For the purposes of making the objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application. Identical or similar reference numerals in the drawings represent identical or similar elements or elements having identical or similar functions throughout. The described embodiments are part of the embodiments of the present application, but not all the embodiments.

[0047] The embodiments described below with reference to the drawings are exemplary and are intended to explain the present application, but cannot be understood as a limitation of the present application.

[0048] Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0049] The drawings will be described below in conjunction with the Figure 1 The embodiments of the present application will be described in detail.

[0050] Embodiment 1

[0051] The present application discloses a helicopter transfer function test suspension method, comprising the following steps:

[0052] A rigid annular suspension disc 2 with a plurality of retaining holes is prepared, wherein the retaining holes are at least 3 and are uniformly distributed on the suspension disc 2;

[0053] A flexible sling 1 is used to pass through the retaining holes and form a rope sleeve connection with the suspension disc 2, and after all the slings 1 are connected, the suspension disc 2 needs to be kept in a horizontal state;

[0054] A rigid hook 3 is connected to each of the above rope sleeves;

[0055] A flexible strap 4 is used, one end of which is tied to the hub central piece support arm, and the other end is connected to the hook 3, and after all the straps 4 are connected, the suspension disc 2 needs to be kept in a horizontal state.

[0056] The suspension method can connect the slings 1 and the suspension disc 2, connect the slings 1 and the hooks 3, and not directly connect the suspension disc 2 and the hooks 3, and connect the straps 4 and the hooks 3. Through the above design, the present application is significantly superior to the existing suspension method in terms of structural stability, functional expandability and durability, and has a wide industrial application prospect.

[0057] The hanging plate 2 is made of high-strength metal (such as aviation aluminum, 45 steel, etc.) into a ring shape, with an inner diameter of 600 mm, an outer diameter of 900 mm, and a thickness of 40 mm, and has the ability to bear in-plane pressure load. Five evenly distributed tie holes are provided on the hanging plate 2, and the edges of the tie holes are smoothly curved. The tie holes have a diameter of 100 mm, and the edges are chamfered to reduce stress concentration or sharp corners that can cut the hanging 1. The evenly distributed tie holes are connected to the five hanging 1s by evenly distributed connection and binding.

[0058] The hanging 1 is made of one or more of flexible steel cable, carbon fiber rope, and nylon cloth woven rope. One end of the hanging 1 is made into a rope knot. After the hanging 1 passes through the tie hole, it passes through the above-mentioned rope knot, thereby forming a rope knot connection with the hanging plate 2. Five flexible steel cables or carbon fiber ropes or nylon cloth woven ropes of equal strength and equal length with a loop hole (rope knot) at the front end are used as the hanging 1. They pass through the evenly distributed tie holes of the hanging plate 2 and are tied to the hanging plate 2 through the loop holes of the ropes. The other end of the hanging 1 can be connected to the load-bearing component through a universal joint.

[0059] The hanging hook 3 is designed in one piece or in two pieces. When designed in one piece, one end is provided with a hanging hole, and the other end is provided with a hook. The hanging hook 3 is sleeved on the hanging 1 through the hanging hole. When designed in two pieces, it includes a damping buffer and two hooks symmetrically arranged at both ends of the damping buffer. One of the hooks is hung on the rope sleeve of the hanging 1, and the other is connected with the binding belt 4. The middle part uses a damping buffer to transition, which can avoid the transmission of impact load. The hanging hook 3 is connected to the rope sleeve of the hanging 1 below the hanging plate 2, not directly connected to the tie holes of the hanging plate 2, and does not contact the hanging plate 2 to produce force interaction.

[0060] The binding belt 4 is a high-toughness nylon rope or cloth woven rope, which has several connection methods.

[0061] The first method is to fold it in half, with one end hanging on the hook and the other end tied to the arm of the central part of the hub.

[0062] The second method is to form a rope knot connection with the hook at one end and to tie the other end to the arm of the central part of the hub.

[0063] The third method is to tie one end to the arm of the central part of the hub and to connect the other end to the hook through a quick release buckle, which supports quick replacement and tension adjustment.

[0064] The binding belt 4 and the hanging 1 are connected through the hanging hook 3, and a safety rope is also provided between the binding belt 4 and the hanging 1 to connect the binding belt 4 and the hanging 1 when the hanging hook 3 breaks.

[0065] The present application ties the 5 belts 4 suspending the 5 arms of the hub central piece on the hooks 3 of the hanger 1 instead of directly on the tie holes of the hanger plate 2.

[0066] The working principle of the present application is as follows:

[0067] 1) Force transmission path: the suspension load is transmitted through the belts 4→ hooks 3→ hangers 1, and finally to the hangers 1. The hanger plate 2 is only subjected to the inward radial pressure generated by the pulling force of the hangers 1, without vertical suspension load component.

[0068] 2) Load sharing mechanism: the flexible characteristics of the hangers 1 cooperate with the universal joint design, allowing each hanger 1 to automatically adjust the tension under dynamic load, ensuring that the 5 hangers 1 are evenly stressed and do not cause unstable suspension.

[0069] 3) Vertical excitation loading: the central area (inner diameter 600mm) of the hanger plate 2 is reserved for space to install hydraulic or electromagnetic exciters to apply vertical vibration or periodic load for structural dynamic testing such as full machine transfer function test.

[0070] Example 2

[0071] The present application discloses a helicopter transfer function test suspension device, which comprises:

[0072] a hanger plate 2, which is designed in a ring shape and has 5 tie holes evenly arranged thereon;

[0073] hangers 1, which are flexible members and have the same number as the tie holes, one end of each hanger 1 passing through a tie hole to form a rope sleeve connection with the hanger plate 2;

[0074] hooks 3, which are rigid members and are connected to the rope sleeves of the hangers 1;

[0075] belts 4, which are flexible members, one end of each belt 4 being tied to an arm of the hub central piece and the other end being connected to the hook 3.

[0076] The suspension load is transmitted through the belts 4→ hooks 3→ hangers 1, and finally to the hangers 1. The hanger plate 2 is only subjected to the inward radial pressure generated by the pulling force of the hangers 1, without vertical suspension load component.

[0077] The hanger plate 2 is made of high-strength metal (such as aviation aluminum, 45 steel, etc.) and has a ring shape, an inner diameter of 600mm, an outer diameter of 900mm, and a thickness of 40mm, and has a planar inward pressure load bearing capacity. Five tie holes are evenly arranged on the hanger plate 2, and the edges of the tie holes are smoothly curved. The tie holes have a diameter of 100mm, and the edges are chamfered to reduce stress concentration or sharp corners that can cut the hangers 1. The evenly distributed tie holes are connected to the 5 hangers 1 for uniform distribution. Alternatively, wear-resistant bushings can be embedded in the tie holes to prevent friction and wear of the hangers 1.

[0078] The hanging 1 is made of one or more of flexible steel cable, carbon fiber rope, and nylon cloth woven rope, one end of the hanging 1 is made into a rope noose, the hanging 1 passes through the tethering hole and then passes through the above-mentioned rope noose, thereby forming a rope noose connection with the hanging plate 2. Five flexible steel cables or carbon fiber ropes or nylon cloth woven ropes with equal strength, equal length and ring holes (rope noose) at the front end as the hanging 1 pass through the evenly distributed tethering holes of the hanging plate 2 and then pass through the ring holes of the ropes to be tied on the hanging plate 2. The other end of the hanging 1 can be connected to the load-bearing component through a universal joint.

[0079] The hanging hook 3 adopts an integrated or split design.

[0080] When the integrated design is adopted, one end of the hanging hook 3 is provided with a hanging hole, and the other end is provided with a hook, and the hanging hook 3 is sleeved on the hanging 1 through the hanging hole.

[0081] When the split design is adopted, it includes a damping buffer and two hooks symmetrically arranged and connected at both ends of the damping buffer, one of which is hung on the rope noose of the hanging 1, and the other is connected with the binding belt 4. The middle part is transitioned by the damping buffer, which can avoid the transmission of impact load. The hanging hook 3 is connected to the rope noose of the hanging 1 below the hanging plate 2, and is not directly connected to the tethering hole of the hanging plate 2, and does not contact the hanging plate 2 to produce force interaction.

[0082] The binding belt 4 is a high-toughness nylon rope or cloth woven rope, which has several connection modes.

[0083] Among them, the first is to fold it in half, one end is hung on the hook, and the other end is tied to the arm of the hub central piece.

[0084] The second is to form a rope noose connection with the hook at one end, and to tie the other end to the arm of the hub central piece.

[0085] The third is to tie one end to the arm of the hub central piece, and the other end is connected to the hook through a quick release buckle, which supports quick replacement and tension adjustment.

[0086] The binding belt 4 and the hanging 1 are connected through the hanging hook 3, and a safety rope is also provided between the binding belt 4 and the hanging 1, which is used to connect the binding belt 4 and the hanging 1 when the hanging hook 3 breaks.

[0087] The present application optimizes the force transmission path, so that the hanging plate 2 only bears radial pressure and avoids bearing the relatively larger vertical tension of the suspension, ensures that multiple hangings 1 bear force uniformly, and improves the stability of the system.

[0088] The present application can implement vertical excitation loading work at the hub center of the helicopter, and can also implement suspension work at the hub center position.

[0089] Thus, the object of the present application is achieved.

[0090] The above is only the preferred embodiment of the present application, and is not used to limit the present application, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A helicopter transfer function test suspension method, characterized by, It comprises the following steps: Prepare a rigid ring-shaped suspension platform with several retaining holes, wherein the retaining holes are at least three and evenly distributed on the suspension platform; Use flexible hangers to pass through the retaining holes and form a rope sleeve connection with the suspension platform, and keep the suspension platform in a horizontal state after all the hangers are connected; Connect a rigid hook to each of the above rope sleeves; Use flexible straps to be tied to the central part of the hub arm on one end and connected to the hook on the other end, and keep the suspension platform in a horizontal state after all the straps are connected.

2. A method of testing a helicopter transfer function suspension according to claim 1, characterised in that, The suspension platform material is high-strength metal, provided with five evenly distributed retaining holes, and the edges of the retaining holes are treated with curved surface smoothing; The hangers are made of one or more of flexible steel cables, carbon fiber ropes, and nylon cloth woven ropes, one end of the hanger is made into a rope sleeve knot, and after the hanger passes through the retaining hole, it passes through the above rope sleeve knot, thereby forming a rope sleeve connection with the suspension platform; The hook is designed in one piece or in two pieces; when designed in one piece, one end is provided with a hanging hole and the other end is provided with a hook, and the hook is sleeved on the hanger through the hanging hole; when designed in two pieces, it includes a damping buffer and two hooks symmetrically arranged at both ends of the damping buffer, one of which is hung on the rope sleeve of the hanger; The strap is a high-toughness nylon rope or cloth woven rope, which is folded in half, one end is hung on the hook, and the other end is tied to the central part of the hub arm; or one end is connected to the hook in a rope sleeve connection, and the other end is tied to the central part of the hub arm.

3. A method of testing a helicopter transfer function suspension according to claim 2, characterised in that, The strap and the hanger are connected through the hook, and a safety rope is also provided between the strap and the hanger to connect the strap and the hanger when the hook breaks.

4. A helicopter transfer function test suspension apparatus, characterised in that, It comprises: The suspension platform is designed in a ring shape, and five retaining holes are evenly provided on the suspension platform; The hanger is a flexible piece, and the number of hangers is the same as the number of retaining holes, one end of the hanger passes through the retaining hole to form a rope sleeve connection with the suspension platform; The hook is a rigid piece connected to the rope sleeve of the hanger; The strap is a flexible piece, one end of which is tied to the central part of the hub arm, and the other end is connected to the hook.

5. A helicopter transfer function test suspension apparatus according to claim 4, characterised in that, Five retaining holes are evenly provided on the suspension platform, and the edges of the retaining holes need to be treated with curved surface smoothing.

6. A helicopter transfer function test suspension apparatus according to claim 5, characterised in that, The hanger is made of one or more of flexible steel cables, carbon fiber ropes, and nylon cloth woven ropes, one end of the hanger is made into a rope sleeve knot, and after the hanger passes through the retaining hole, it passes through the above rope sleeve knot, thereby forming a rope sleeve connection with the suspension platform.

7. A helicopter transfer function test suspension apparatus according to claim 6, characterised in that, One end of the hook is provided with a hanging hole, and the other end is provided with a hook, and the hook is sleeved on the hanger through the hanging hole.

8. A helicopter transfer function test suspension apparatus according to claim 6, wherein, The hook is designed in two pieces, including a damping buffer and two hooks symmetrically arranged at both ends of the damping buffer, one of which is hung on the rope sleeve of the hanger.

9. A helicopter transfer function test suspension apparatus according to claim 7 or 8, characterised in that, The strap is a high-toughness nylon rope or cloth woven rope, which is folded in half, one end is hung on the hook, and the other end is tied to the central part of the hub arm; or one end is connected to the hook in a rope sleeve connection, and the other end is tied to the central part of the hub arm.

10. A helicopter transfer function test suspension apparatus according to claim 9, characterised in that, A safety rope is also provided between the strap and the hanger to connect the strap and the hanger when the hook breaks.

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