A helicopter cooling fan testing apparatus

Abstract

The utility model discloses a kind of helicopter cooling fan test equipment, belong to aviation department accessory maintenance field;Equipment main body is horizontal frame structure, by base, flow limiting air pipe, fan mounting rack, angle adjusting lever and locking clamp composition;Parallel slide rail is equipped on base, flow limiting air pipe can be infinitely variable displacement along slide rail and be quickly locked;Fan mounting rack one end is hinged with base, the other end is realized by angle adjusting lever pitch angle infinitely variable adjustment and lock dead;Same set of device can be adapted to different air cylinder angle and axial length of all models helicopter cooling fan, without replacing mounting support, the utility model has the characteristics that structure is simple, easy to operate, small, test cost is low, safety factor is high, can be completed function test, performance inspection and fault location once.

Description

Technical Field

[0001] This utility model relates to the field of aviation accessory maintenance technology, and in particular to a helicopter cooling fan testing device. Background Technology

[0002] Helicopter cooling fans come in a wide variety, with different models having varying angles between the fan duct's central axis and the mounting flange surface, as well as inconsistent axial lengths of the fan duct. Traditional testing fixtures use a dedicated bracket for each model, requiring complete disassembly and reassembly of the bracket for every model change, leading to:

[0003] The preparation period is long, and frequent disassembly and assembly increase the workload.

[0004] The number of dedicated brackets increases exponentially with random variations, occupying a large amount of factory space and incurring high maintenance costs.

[0005] Multiple processing steps result in waste of steel, processing time, and coating materials, which is inconsistent with the concept of green maintenance.

[0006] The disassembly and assembly process poses safety hazards such as falling and pinching.

[0007] Therefore, there is an urgent need for a universal testing device that does not require changing the bracket and can quickly adjust the angle and axial position to meet the need for functional testing of multiple types of fans at the same workstation. Utility Model Content

[0008] The purpose of this invention is to provide a helicopter cooling fan testing device, thereby solving the aforementioned problems existing in the prior art.

[0009] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0010] A helicopter cooling fan testing device includes:

[0011] A rectangular base arranged horizontally, the base is a frame formed by welding two long side frames and two short side frames.

[0012] Two parallel X-axis slide rails are fixed along the upper surface of the long frame of the base.

[0013] The flow-limiting duct is slidably installed on the X-axis slide rail by means of the flow-limiting duct locking clamp, and the axis of the flow-limiting duct is parallel to the X-axis slide rail;

[0014] The fan mounting bracket is located at one end of the base. The bottom end of the fan mounting bracket is hinged to a short frame of the base adjacent to the fan mounting bracket. An angle adjustment rod is also provided on the side frame of the fan mounting bracket. The side frame of the fan mounting bracket is adjustablely connected to the long frame of the base through the angle adjustment rod.

[0015] The lower end of the angle adjustment rod is hinged to the long frame, and the upper end is provided with an arc groove. The side frame of the fan mounting bracket is connected to the arc groove by bolts, forming a structure that allows for stepless angle adjustment and locking.

[0016] In some specific embodiments, the flow-limiting duct locking clamp includes: a U-shaped screw, a pressure plate, and two M8 locking nuts; the U-shaped screw straddles the X-axis slide rail, the pressure plate presses against the upper surface of the flange of the flow-limiting duct, and the flow-limiting duct is fixed to the base by tightening the M8 locking nuts.

[0017] In some specific embodiments, the flow-limiting duct is a PVC rack pipe, whose outer circular surface matches the arc-shaped concave surface of the pressure plate, and whose lower surface of the flange edge slides in contact with the upper surface of the X-axis slide rail to achieve X-axis displacement adjustment.

[0018] In some specific embodiments, it further includes: a hinged support; the hinged support is welded to the center of the upper surface of the short frame of the base, and the two side walls of the hinged support have coaxial hinge holes. The corresponding end of the fan mounting bracket is inserted between the two side walls of the hinged support and connected by M8 hinge bolts and M8 lock nuts to form a horizontal rotation shaft.

[0019] In some specific embodiments, the rod body of the angle adjustment rod is a 45×45×5Q235A equilateral angle steel, and its lower end is hinged to the long frame of the base through another set of hinged supports. The center of the upper arc groove coincides with the lower hinge axis, and an angle scale is provided next to the arc groove.

[0020] In some specific embodiments, the side frame of the fan mounting bracket is welded with a boss with a threaded hole at the corresponding arc groove position. An M8 bolt passes through the arc groove and screws into the boss to lock the fan mounting bracket and the angle adjustment rod.

[0021] In some specific embodiments, the fan mounting bracket is a rectangular frame welded together with a long frame and a short frame. The long frame is made of 50×50×5 Q235A angle steel, and the short frame is made of 45×45×5 Q235A angle steel. A safety net is welded inside the rectangular frame, and a fan mounting hole is provided in the center of the safety net.

[0022] In some specific embodiments, the fan mounting holes are four elongated holes arranged in a rectangular pattern to accommodate helicopter cooling fans with different flange hole spacings.

[0023] In some specific embodiments, the X-axis slide rail is made of 50×50×5 Q235A angle steel. Its horizontal side is welded to the upper surface of the long frame of the base, and its vertical side serves as a limiting stop, fitting against the inner side of the U-shaped screw of the flow-limiting duct locking clamp to prevent the flow-limiting duct from moving in the Y direction.

[0024] In some specific embodiments, all angle steel parts are connected by continuous fillet welds with a weld height of not less than 5mm. The entire surface is coated with anti-rust primer and yellow safety warning topcoat to meet the explosion-proof and 6S management requirements of aviation maintenance workshops.

[0025] The beneficial effects of this utility model are:

[0026] High versatility: Through the combined adjustment of the angle adjustment rod and the slide rail, it can cover the duct angle and axial dimension of all helicopter cooling fans, realizing "one machine to measure all types".

[0027] High testing efficiency: The replacement of the dedicated bracket is eliminated, reducing the changeover time from 2 hours to 5 minutes, and reducing the testing cycle of a single fan by more than 40%.

[0028] Low cost: The entire set of equipment uses only conventional angle steel, PVC pipes and standard fasteners, which are simple to process and the material cost is less than 20% of the total cost of traditional multiple sets of special brackets.

[0029] Small footprint: The horizontal and compact structure occupies less than 1m², allowing for more testing stations to be arranged in the same factory area.

[0030] High safety: The fan mounting bracket comes with a protective net to prevent the blades from flying out accidentally; each adjustment position is equipped with a locking mechanism to prevent loosening due to vibration during testing.

[0031] Green maintenance significantly reduces repeated steel processing and painting, lowers carbon emissions, and meets the requirements for sustainable development in aviation maintenance. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the adjustment of angle 'a' in the digital model isometric projection of the testing equipment of this utility model;

[0033] Figure 2 This is a schematic diagram of the adjustment b of the digital model isometric projection angle of the testing equipment of this utility model;

[0034] Figure 3 This is a diagram illustrating the configuration of the testing equipment of this utility model;

[0035] Figure 4 These are two-dimensional three-view drawings of the testing equipment of this utility model.

[0036] In the attached diagram: 10. Base; 11. Long frame; 12. Short frame; 20. Flow-limiting duct; 30. Flow-limiting duct locking clamp; 40. Fan mounting bracket; 41. Long frame; 42. Short frame; 43. Safety net; 50. Angle adjustment rod. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the scope of the present utility model.

[0038] Reference Figure 1 , Figure 2 , Figure 3 and Figure 4 The helicopter cooling fan testing device shown includes:

[0039] A rectangular base 10 is arranged horizontally. The base 10 is formed by welding two long side frames 11 and two short side frames 12 into a frame shape.

[0040] Two parallel X-axis slide rails are fixed along the upper surface of the long frame 11 of the base 10.

[0041] The flow-limiting duct 20 is slidably installed on the X-axis slide rail via the flow-limiting duct locking clamp 30, and the axis of the flow-limiting duct 20 is parallel to the X-axis slide rail;

[0042] The fan mounting bracket 40 is located at one end of the base 10. The bottom end of the fan mounting bracket 40 is hinged to a short frame 12 on the base 10 adjacent to the fan mounting bracket 40. An angle adjustment rod 50 is also provided on the side frame of the fan mounting bracket 40. The side frame of the fan mounting bracket 40 is adjustablely connected to the long frame 11 of the base 10 through the angle adjustment rod 50.

[0043] The lower end of the angle adjustment rod 50 is hinged to the long frame 11, and the upper end is provided with an arc groove. The side frame of the fan mounting bracket 40 is connected to the arc groove by bolts to form a structure with stepless angle adjustment and locking.

[0044] In this embodiment, the overall structure is as follows: The testing equipment is a horizontal rectangular frame, placed on the ground or a workbench. The frame is formed by welding two long side frames and two short side frames end to end, forming a horizontal rectangular base. On the upper surface of each long side frame, an angle steel with a "┐" shaped cross-section is fixed along its entire length as an X-axis slide rail. The two slide rails are parallel to each other and the spacing is fixed. The vertical flanges of the slide rails face upwards and are used for lateral limiting.

[0045] The flow-limiting duct is a section of PVC round pipe, the outer diameter of which matches the outlet of the helicopter cooling fan. The rear end of the duct has an annular flange. This flange is clamped between the pressure plate of the flow-limiting duct locking clamp and the horizontal flange of the slide rail. A U-shaped screw straddles the slide rail, passes downwards through the through holes at both ends of the pressure plate, and is then locked with two M8 nuts. Loosening the nuts eliminates the clamping force between the pressure plate and the slide rail, allowing the flow-limiting duct to slide steplessly along the slide rail. Tightening the nuts compresses the flange, instantly locking the duct in the X-axis, achieving integrated displacement adjustment and positioning.

[0046] The fan mounting bracket is located at the front end of the base. Two parallel lugs extend downwards from the end closest to the short frame. These lugs are inserted between the two side walls of the hinged support welded to the upper surface of the short frame. A horizontal M8 bolt forms the hinge axis, allowing the fan mounting bracket to tilt and swing vertically around this axis. The main body of the mounting bracket is a rectangular frame with a safety mesh welded inside. Four elongated holes are pre-drilled in the center to accommodate cooling fans with different flange hole spacings.

[0047] The angle adjustment rod is also made of angle steel, with its lower end hinged to the long frame of the base via a second set of hinged supports. The upper end has an arc-shaped groove centered on the hinge axis. A boss with threaded holes is welded to the corresponding position on the side frame of the fan mounting bracket. An M8 bolt passes through the arc-shaped groove and screws into the boss; when the bolt is loosened, the boss slides along the arc-shaped groove, causing the fan mounting bracket to change its pitch angle; when the bolt is tightened, the boss and the angle adjustment rod are clamped together, locking the pitch angle. Angle markings are engraved on the edge of the arc-shaped groove for easy reading.

[0048] II. Dynamic Working Process

[0049] Pre-adjustment stage

[0050] Based on the angle of the fan duct under test, first loosen the M8 bolt on the angle adjustment rod, move the fan mounting bracket to the target angle indicated by the scale, and then tighten the bolt to lock the pitch angle. Next, loosen the nut on the flow-limiting duct locking clamp, push and pull the flow-limiting duct until the distance between its inlet end face and the outer end face of the fan is equal to the axial length of the duct, and then tighten the nut to complete the X-axis positioning. The order of the above two steps can be interchanged.

[0051] Clamping stage

[0052] Place the cooling fan inside the safety guardrail, aligning its flange with the oblong hole of the mounting bracket, and secure the fan with four bolts. At this point, the fan axis is coaxial with the flow-limiting duct axis, and the axial clearance has been eliminated.

[0053] Testing phase

[0054] Once the fan is powered on, it rotates at high speed under the protection of the safety net, and the airflow directly enters the flow-limiting duct, forming a stable flow field. The testing instrument can collect air volume, air pressure, speed, and noise parameters at the duct outlet. If it is necessary to replace a different fan model, only the three steps of "loosening bolts - adjusting angle - sliding duct - tightening" need to be repeated. No disassembly or replacement of any brackets is required, and the entire process can be completed with one hand within 5 minutes.

[0055] Reset phase

[0056] After the test is completed, disconnect the power and remove the fan after it stops rotating. If the next fan is of the same specification, it can be directly clamped. If the specifications are different, the arc groove and slide rail can be used again to compensate for the angle and displacement, so that continuous operation can be carried out.

[0057] Through the above structure and its linkage mechanism, the equipment can perform functional testing, performance inspection and fault location of all models of helicopter cooling fans in a single workstation, meeting the requirements of the Patent Law for utility models of "novelty, inventiveness and utility".

[0058] Figure 1 , Figure 2 The image shows a comparison of the same test equipment at two typical pitch angles, which is used to visually demonstrate the linkage between the angle adjustment rod and the fan mounting bracket.

[0059] exist Figure 1 In this configuration, the locking bolt at the upper end of the angle adjustment rod is located at the lowest point of the arc-shaped groove. At this time, the fan mounting bracket is in a horizontal position, and its axis is parallel to the upper surface of the base. This configuration is suitable for cooling fans with a 0° outlet angle. It can be seen that the flange edge of the flow-limiting duct maintains a minimum axial distance from the outer end face of the fan. The entire device is in a "low-position and straight" posture with a low center of gravity, which facilitates quick clamping.

[0060] exist Figure 2 After loosening the locking bolts, lift the rear end of the fan mounting bracket upwards, allowing the bolts to slide along the arc-shaped groove to near the top, then tighten the nuts. The mounting bracket will then rotate upwards approximately 45° around the front hinge axis, resulting in a "head-up" position. At this point, the fan axis forms a distinct angle with the upper surface of the base, and the flow-limiting duct simultaneously retracts along the slide rail, while its inlet end face remains coaxially aligned with the fan outlet end face, ensuring a continuous flow field. This configuration is compatible with various types of fans with duct outlet angles ranging from 30° to 60°, without requiring any parts replacement.

[0061] As can be seen from the comparison of the two pictures, it is only necessary to tighten or loosen one bolt and push or pull the air duct once to complete the continuous conversion from "horizontal" to "large tilt angle". The angle scale line is placed to the side, and the adjustment process can be operated with one hand, which fully demonstrates the equipment's advantages of "stepless, visual and quick lock" angle adjustment.

[0062] In some specific embodiments, the flow-limiting duct locking clamp 30 includes: a U-shaped screw, a pressure plate and two M8 locking nuts; the U-shaped screw straddles the X-axis slide rail, the pressure plate presses on the upper surface of the flange of the flow-limiting duct 20, and the flow-limiting duct 20 is fixed to the base 10 by tightening the M8 locking nuts.

[0063] In some specific embodiments, the flow-limiting duct 20 is a PVC rack pipe, whose outer circular surface matches the arc concave surface of the pressure plate, and whose lower surface of the flange edge slides in contact with the upper surface of the X-axis slide rail to achieve X-axis displacement adjustment.

[0064] In some specific embodiments, it also includes: a hinge support; the hinge support is welded to the center of the upper surface of the short frame 12 of the base 10, and the two side walls of the hinge support have coaxial hinge holes. The corresponding ends of the fan mounting bracket 40 are inserted between the two side walls of the hinge support and connected by M8 hinge bolts and M8 anti-loosening nuts to form a horizontal rotation shaft.

[0065] In some specific embodiments, the rod body of the angle adjustment rod 50 is a 45×45×5Q235A equilateral angle steel, and its lower end is hinged to the long frame 11 of the base 10 through another set of hinged supports. The center of the upper arc groove coincides with the lower hinge axis, and an angle scale is provided next to the arc groove.

[0066] In some specific embodiments, the side frame of the fan mounting bracket 40 is welded with a boss with a threaded hole at the corresponding arc groove position. An M8 bolt passes through the arc groove and is screwed into the boss to lock the fan mounting bracket 40 and the angle adjustment rod 50.

[0067] In some specific embodiments, the fan mounting bracket 40 is a rectangular frame welded together with a long frame 41 and a short frame 42. The long frame 41 is made of 50×50×5 Q235A angle steel, and the short frame 42 is made of 45×45×5 Q235A angle steel. A safety net 43 is welded inside the rectangular frame, and a fan mounting hole is provided in the center of the safety net 43.

[0068] In some specific embodiments, the fan mounting holes are four elongated holes arranged in a rectangular pattern to accommodate helicopter cooling fans with different flange hole spacings.

[0069] In some specific embodiments, the X-axis slide rail is made of 50×50×5 Q235A angle steel. Its horizontal side is welded to the upper surface of the long frame 11 of the base, and its vertical side serves as a limiting stop, fitting against the inner side of the U-shaped screw of the flow-limiting duct locking clamp 30 to prevent the flow-limiting duct 20 from moving in the Y direction.

[0070] In some specific embodiments, all angle steel parts are connected by continuous fillet welds with a weld height of not less than 5mm. The entire surface is coated with anti-rust primer and yellow safety warning topcoat to meet the explosion-proof and 6S management requirements of aviation maintenance workshops.

[0071] Working principle:

[0072] This equipment utilizes the mechanical principle of "two-point positioning, one-axis rotation, and bidirectional stepless locking" to quickly adapt helicopter cooling fans of different specifications. The fan mounting bracket uses the hinged support on the short frame of the base as the fixed rotation center. The arc-shaped groove on the angle adjustment rod is concentric with the same rotation center, forming a "swing rod-slide groove" mechanism in a rigid four-bar linkage. Loosening or tightening the single locking bolt allows for stepless adjustment of the fan pitch angle within the range of 0° to 60°, and instantaneous locking at any angle. Simultaneously, the flow-limiting duct can slide steplessly in the X-axis direction through a quick-release clamp consisting of a "U-shaped screw-pressure plate-slide rail". The same set of clamps provides both guidance and locking, ensuring that the duct inlet end face and the fan outlet end face remain coaxial and the axial clearance is controllable. The linkage of these two components can compensate for the differences in the duct angle and length of different fans in three-dimensional space, achieving "one machine for all types".

[0073] By adopting the above-disclosed technical solution of this utility model, the following beneficial effects are obtained:

[0074] Compared with the traditional "one type, one bracket" solution, this utility model reduces the preparation time for model changeover from 2 hours to 5 minutes, reduces the number of brackets to zero, and a single device can cover all the cooling fans of currently in service helicopters. The entire set of equipment is welded using only commercially available angle steel, PVC pipes, and standard fasteners. The material cost is less than 20% of the total cost of multiple traditional dedicated brackets. It occupies less than 1m², has fewer welds, is lightweight, and is easy to maintain. All adjustment positions are equipped with locking mechanisms and protective nets to prevent the risk of blades flying out or ducts shifting during high-speed rotation, meeting the requirements of explosion-proof, 6S management, and green maintenance in aviation maintenance workshops.

[0075] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A helicopter cooling fan testing device, characterized in that, include: A rectangular base (10) arranged horizontally, wherein the base (10) is a frame formed by welding two long side frames and two short side frames. Two parallel X-axis slide rails are fixed along the upper surface of the long frame of the base (10); The flow-limiting duct (20) is slidably installed on the X-axis slide rail by the flow-limiting duct locking clamp (30), and the axis of the flow-limiting duct (20) is parallel to the X-axis slide rail; The fan mounting bracket (40) is located at one end of the base (10). The bottom end of the fan mounting bracket (40) is hinged to a short frame of the base (10) adjacent to the fan mounting bracket (40). An angle adjustment rod (50) is also provided on the side frame of the fan mounting bracket (40). The side frame of the fan mounting bracket (40) is adjustablely connected to the long frame of the base (10) through the angle adjustment rod (50). The lower end of the angle adjustment rod (50) is hinged to the long frame, and the upper end is provided with an arc groove. The side frame of the fan mounting bracket (40) is connected to the arc groove by bolts to form a structure with stepless angle adjustment and locking.

2. The testing equipment according to claim 1, characterized in that: The flow-limiting duct locking clamp (30) includes: a U-shaped screw, a pressure plate and two M8 locking nuts; the U-shaped screw straddles the X-axis slide rail, the pressure plate presses on the flange side of the flow-limiting duct (20), and the flow-limiting duct (20) is fixed to the base (10) by tightening the M8 locking nuts.

3. The testing equipment according to claim 2, characterized in that: The flow-limiting duct (20) is a PVC rack pipe, whose outer circular surface matches the arc concave surface of the pressure plate, and the lower surface of the flange edge slides in contact with the upper surface of the X-axis slide rail to achieve X-axis displacement adjustment.

4. The testing equipment according to claim 3, characterized in that: Also includes: Hinged support; the hinged support is welded to the center of the upper surface of the short frame of the base (10). The two side walls of the hinged support have coaxial hinge holes. The corresponding ends of the fan mounting bracket (40) are inserted between the two side walls of the hinged support and connected by M8 hinge bolts and M8 anti-loosening nuts to form a horizontal rotating shaft.

5. The testing equipment according to claim 4, characterized in that: The angle adjustment rod (50) is made of 45×45×5 Q235A equilateral angle steel. Its lower end is hinged to the long frame of the base (10) through another set of hinged supports. The center of the upper arc groove coincides with the lower hinge axis. An angle scale is provided next to the arc groove.

6. The testing equipment according to claim 5, characterized in that: The side frame of the fan mounting bracket (40) has a boss with a threaded hole welded at the position corresponding to the arc groove. An M8 bolt passes through the arc groove and is screwed into the boss to lock the fan mounting bracket (40) and the angle adjustment rod (50).

7. The testing equipment according to claim 1, characterized in that: The fan mounting bracket (40) is a rectangular frame welded together with a long frame and a short frame. The long frame is made of 50×50×5 Q235A angle steel, and the short frame is made of 45×45×5 Q235A angle steel. A safety net (43) is welded inside the rectangular frame, and a fan mounting hole is provided in the center of the safety net (43).

8. The testing equipment according to claim 7, characterized in that: The fan mounting holes are four elongated holes arranged in a rectangular pattern, designed to accommodate helicopter cooling fans with different flange hole spacings.

9. The testing equipment according to claim 1, characterized in that: The X-axis slide rail is made of 50×50×5 Q235A angle steel. Its horizontal side is welded to the upper surface of the long frame of the base, and its vertical side serves as a limiting stop, which fits against the inner side of the U-shaped screw of the flow-limiting duct locking clamp (30) to prevent the flow-limiting duct (20) from moving in the Y direction.

10. The testing equipment according to any one of claims 1-9, characterized in that: All angle steel parts are connected by continuous fillet welds with a weld height of not less than 5mm. The entire surface is coated with anti-rust primer and yellow safety warning topcoat to meet the explosion-proof and 6S management requirements of the aviation maintenance workshop.

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