Diffuser for micro turbojet engine

Abstract

The utility model discloses a diffuser of micro turbojet engine, it includes mounting disc, diffuser sub -blade is connected with the diffuser secondary vane through the abutment plate and the lock bolt dismounting of mounting groove of mounting disc rear surface is equipped with a plurality, the inner wall of abutment plate is equipped with the locating groove, the inside of locating groove is provided with spring washer. The mounting groove of mounting disc rear surface provides accurate positioning for diffuser secondary vane, guarantees the even distribution of blade circumferential distribution, avoids radial swing, the detachable connection of abutment plate and lock bolt realizes secondary vane convenient dismounting and maintenance, and the lock bolt of symmetrical locking forms rigid connection, prevents loosening, and the locating groove of abutment plate inner wall provides installation datum for spring washer, and the gasket offsets vibration gap through elastic deformation, and its abutment with the blade can compensate thermal expansion and contraction, enhance blade installation stability, avoid the displacement of air flow thrust, guarantee the shape accuracy of diffuser passage.

Description

Technical Field

[0001] This utility model relates to the field of turbojet engine technology, and in particular to the diffuser of a micro turbojet engine. Background Technology

[0002] Micro turbojet engines, with their compact structure and powerful performance, are widely used in drones, target drones, and small aircraft. The diffuser, as a key component, directly affects the overall performance of the engine. Centrifugal compressors, due to their simple construction, low manufacturing cost, and high single-stage pressure ratio, have become an ideal choice for micro-sized aero-engines. Their diffusers typically consist of a radial diffuser, a turning section, and an axial diffuser. Usually, the airflow at the centrifugal impeller outlet is transonic, requiring the radial diffuser to quickly slow down the high-speed airflow, efficiently converting kinetic energy into pressure potential energy.

[0003] Traditional blades are mostly fixed connections without a removable structure such as anti-locking plates and anti-loosening bolts. Replacing or repairing blades requires disassembling a large number of related components, which is cumbersome and time-consuming, significantly increasing maintenance costs. In addition, traditional fixing methods lack a rigid connection design with symmetrical locking, and bolts are easily loosened by vibration, resulting in gaps between the blades and the mounting structure, which exacerbates airflow disturbance and component wear. Utility Model Content

[0004] The purpose of this invention is to provide a diffuser for a micro turbojet engine. The mounting groove on the rear surface of the mounting plate provides precise positioning for the secondary blades of the diffuser, ensuring uniform circumferential distribution of the blades and preventing radial sway. The detachable connection of the contact plate and anti-loosening bolts allows for convenient disassembly and maintenance of the secondary blades. The symmetrically locked anti-loosening bolts form a rigid connection to prevent loosening. The positioning groove on the inner wall of the contact plate provides an installation reference for the spring washer. The washer compensates for vibration gaps through elastic deformation, and its contact with the blades compensates for thermal expansion and contraction, enhancing blade installation stability, preventing displacement due to airflow thrust, and ensuring the shape accuracy of the diffuser channel.

[0005] To achieve the above objectives, a diffuser for a micro turbojet engine is provided, comprising: a mounting plate and a diffuser assembly. The rear surface of the mounting plate has several mounting slots. Secondary diffuser blades are detachably connected to these mounting slots via contact plates and anti-loosening bolts. The inner wall of the contact plate has a positioning groove, and a spring washer is installed inside the positioning groove. Elastic deformation compensates for vibration gaps, thermal expansion and contraction, and enhances blade installation stability.

[0006] The anti-loosening bolts are symmetrically arranged on the upper and lower sides of the rear surface of the contact plate, and the number of contact plates corresponds to the number of mounting slots. This ensures that each blade is effectively clamped, and the balanced force ensures the stability of the overall structure.

[0007] The anti-loosening bolts extend into the interior of the mounting plate, and the dimensions of the diffuser secondary blades are matched to the dimensions of the mounting slot. This prevents radial movement after installation and ensures that the shape accuracy of the airflow channel meets design requirements.

[0008] The positioning groove extends into the interior of the diffuser's secondary blades, and the size of the spring washer is adapted to the size of the positioning groove. This prevents the washer from shifting within the groove, fully utilizing its anti-loosening and vibration-damping functions.

[0009] The contact plate is located behind the secondary blades of the diffuser, and the front surface of the spring washer abuts against the secondary blades of the diffuser. Continuous elastic pressure compensates for dimensional changes and maintains the tightness of the blade installation.

[0010] The diffuser assembly is located on the front surface of the mounting plate. The diffuser assembly includes a main oil line connector through hole, an intake cap locking screw hole, an ignition line connector through hole, a diffuser locking screw hole, a bearing sleeve fixing step, and diffuser primary blades. The front surface of the mounting plate has the main oil line connector through hole, the intake cap locking screw hole, and the ignition line connector through hole. The front surface of the mounting plate also has several diffuser primary blades and a bearing sleeve fixing step. The inner surface of the bearing sleeve fixing step has diffuser locking screw holes. This achieves a rigid connection between the diffuser assembly and the bearing sleeve, enhancing the overall structural rigidity.

[0011] The main oil circuit connector through hole, the intake cap locking screw hole, and the ignition line connector through hole all extend to the front surface of the diffuser primary blades. The diffuser secondary blades are located on the outer surface of the mounting plate, and the bearing sleeve fixing step is located in the middle of the front surface of the mounting plate. This ensures concentricity by being positioned at the center of rotation, reducing rotational vibration and improving operational stability.

[0012] The above-mentioned solution has the following beneficial effects: This utility model includes an installation groove, a contact plate, anti-loosening bolts, secondary diffuser blades, a positioning groove, and spring washers. The installation groove on the rear surface of the installation plate provides precise positioning for the secondary diffuser blades, ensuring uniform circumferential distribution of the blades and preventing radial swaying. The detachable connection of the contact plate and anti-loosening bolts allows for convenient disassembly and maintenance of the secondary blades. The symmetrically locked anti-loosening bolts form a rigid connection to prevent loosening. The positioning groove on the inner wall of the contact plate provides an installation reference for the spring washers. The washers compensate for vibration gaps through elastic deformation, and their contact with the blades compensates for thermal expansion and contraction, enhancing the installation stability of the blades, preventing displacement due to airflow thrust, and ensuring the shape accuracy of the diffuser channel. Attached Figure Description

[0013] Figure 1 This is a perspective view of the diffuser of the micro turbojet engine of this utility model.

[0014] Figure 2This is a front view of the diffuser of the micro turbojet engine of this utility model.

[0015] Figure 3 This is a cross-sectional perspective view of the diffuser of the micro turbojet engine of this utility model.

[0016] Figure 4 This utility model Figure 3 Enlarged view of the structure at point A in the middle.

[0017] Legend: 1. Mounting plate; 2. Secondary diffuser blades; 3. Primary diffuser blades; 4. Main oil line connector through hole; 5. Intake cap locking screw hole; 6. Ignition line connector through hole; 7. Diffuser locking screw hole; 8. Bearing sleeve fixing step; 9. Mounting groove; 10. Abutment plate; 11. Positioning groove; 12. Spring washer; 13. Anti-loosening bolt. Detailed Implementation

[0018] Reference Figure 1-4 The present invention relates to a diffuser for a micro turbojet engine, comprising a mounting plate 1 and a diffuser assembly. The rear surface of the mounting plate 1 has several mounting grooves 9, which provide a precise mounting and positioning base for the secondary blades 2 of the diffuser, ensuring uniform circumferential distribution of the blades. The secondary blades 2 of the diffuser are detachably connected to the mounting grooves 9 via abutment plates 10 and anti-loosening bolts 13, realizing detachable fixing of the secondary blades, which facilitates later maintenance, replacement and position adjustment. The inner wall of the abutment plate 10 has a positioning groove 11, which provides installation space and positioning reference for the spring washer 12. The spring washer 12 is set inside the positioning groove 11, which offsets the gap generated by vibration through elastic deformation, enhancing the stability of the secondary blade installation.

[0019] Anti-loosening bolts 13 are symmetrically arranged on the upper and lower sides of the rear surface of the contact plate 10. They secure the contact plate to the mounting plate via symmetrical force application, preventing loosening. The number of contact plates 10 corresponds to the number of mounting slots 9, ensuring uniform clamping force for the secondary blades in each slot. The anti-loosening bolts 13 extend into the interior of the mounting plate 1, forming a through-type fixing structure that rigidly connects the contact plate, secondary blades, and mounting plate into a single unit. The dimensions of the diffuser secondary blades 2 are matched to the dimensions of the mounting slots 9 to prevent radial wobbling after installation and ensure the accuracy of the airflow channel shape. The positioning slot 11 extends into the interior of the diffuser secondary blades 2, allowing the spring washers to simultaneously... The spring washer 12 contacts the abutment plate and the secondary blades, forming a bidirectional elastic preload. The size of the spring washer 12 matches the size of the positioning groove 11, ensuring that the washer does not move within the groove and fully exerting its anti-loosening and shock-absorbing function. The abutment plate 10 is located behind the secondary blades 2 of the diffuser, limiting the blades from the downstream direction of the airflow to prevent the blades from being displaced by the thrust of the airflow. The front surface of the spring washer 12 abuts against the secondary blades 2 of the diffuser, compensating for the dimensional changes caused by the thermal expansion and contraction of the blades through continuous elastic pressure. The diffuser assembly is located on the front surface of the mounting plate 1, forming a front-to-back coordinated airflow diffuser structure with the secondary blades on the rear surface. The diffuser assembly includes the main oil circuit connector through hole 4 and the intake cover locking screw hole 5. The mounting plate 1 features an ignition line connector through-hole 6, a diffuser locking screw hole 7, a bearing sleeve fixing step 8, and a diffuser primary blade 3, integrating multiple functions such as airflow guidance, pipeline connection, and structural fixation. The front surface of the mounting plate 1 has a main oil line connector through-hole 4, an intake cap locking screw hole 5, and an ignition line connector through-hole 6, providing passageways and connection interfaces for the engine oil line, air line, and ignition system pipelines. The front surface of the mounting plate 1 is equipped with several diffuser primary blades 3, which, in conjunction with secondary blades, form a multi-stage diffusion channel, gradually reducing airflow velocity and increasing pressure. The front surface of the mounting plate 1 also features a bearing sleeve fixing step 8, providing axial positioning and radial support for the bearing sleeve, ensuring the rotation of the part... To ensure the coaxiality of the components, the inner surface of the bearing sleeve fixing step 8 is provided with a diffuser locking screw hole 7, which is used to rigidly connect the diffuser assembly to the bearing sleeve, thereby enhancing the overall structural rigidity. The main oil circuit connector through hole 4, the intake cover locking screw hole 5, and the ignition pipeline connector through hole 6 all extend to the front surface of the diffuser primary blade 3, ensuring that the pipeline interface avoids the blade structure and avoids airflow interference and pipeline wear. The diffuser secondary blade 2 is located on the outer surface of the mounting plate 1, forming an outer airflow diffusion channel, which together with the inner primary blade covers the entire flow channel cross section. The bearing sleeve fixing step 8 is located in the middle of the front surface of the mounting plate 1, at the center of rotation, ensuring the concentricity of the bearing sleeve and the mounting plate and reducing rotational vibration.

[0020] Working principle: First, check the dimensional accuracy of the mounting groove 9 on the rear surface of the mounting plate 1 to ensure that the secondary diffuser blade 2 is sized to fit the mounting groove 9. Verify the quantity of components such as the contact plate 10, spring washer 12, and anti-loosening bolt 13 to ensure they correspond to the quantity in the mounting groove 9. Embed the secondary diffuser blade 2 into the mounting groove 9 of the mounting plate 1, ensuring that the blade has no radial wobble. Place the appropriately sized spring washer 12 in the positioning groove 11 on the inner wall of the contact plate 10, making the washer completely fit the inner surface of the groove. Attach the contact plate 10 to the rear of the secondary diffuser blade 2, ensuring that the positioning groove 11 extends into the interior of the secondary blade, so that the front surface of the spring washer 12 abuts against the blade. Symmetrically lock the contact plate 10 and the mounting plate 1 with the anti-loosening bolt 13, ensuring that the bolts extend into the interior of the mounting plate to form a rigid connection. The elastic deformation of the spring washer eliminates the impact of the vibration. To address the vibration gap, position the bearing sleeve and fix the step 8 on the front surface of the mounting plate 1, placing it at the center of rotation. Secure the bearing sleeve to the mounting plate using the diffuser locking screw hole 7 on the inner surface of the step 8, ensuring coaxiality of the rotating components. Confirm the positions of the main oil line connector through hole 4, the intake cap locking screw hole 5, and the ignition line connector through hole 6 on the front surface of the mounting plate 1, ensuring they extend to the front surface of the diffuser primary blade 3 and avoid the blade structure. Insert the corresponding pipes into the through holes, completing the interface connections for the oil line, air line, and ignition system. Check the circumferential uniformity of the diffuser primary blade 3 and secondary blades to ensure they form a complete diffusion channel. Verify the tightness of all connections. Compensate for thermal expansion and contraction gaps using the elastic pressure of spring washers, ultimately forming a coordinated front and rear airflow diffusion structure.

Claims

1. A diffuser for a micro turbojet engine, characterized in that: The assembly includes a mounting plate (1) and a diffuser assembly. The rear surface of the mounting plate (1) is provided with several mounting slots (9). The mounting slots (9) are connected to the diffuser secondary blades (2) by means of a contact plate (10) and anti-loosening bolts (13). The inner wall of the contact plate (10) is provided with a positioning slot (11). A spring washer (12) is provided inside the positioning slot (11).

2. The diffuser of the micro turbojet engine according to claim 1, characterized in that: The anti-loosening bolts (13) are symmetrically arranged on the upper and lower sides of the rear surface of the contact plate (10), and the number of contact plates (10) and the number of mounting slots (9) are arranged accordingly.

3. The diffuser of the micro turbojet engine according to claim 1, characterized in that: The anti-loosening bolt (13) extends into the interior of the mounting plate (1), and the size of the diffuser secondary blade (2) is adapted to the size of the mounting groove (9).

4. The diffuser of the micro turbojet engine according to claim 1, characterized in that: The positioning groove (11) extends into the interior of the diffuser secondary blade (2), and the size of the spring washer (12) is adapted to the size of the positioning groove (11).

5. The diffuser of the micro turbojet engine according to claim 1, characterized in that: The contact plate (10) is located behind the diffuser secondary blade (2), and the front surface of the spring washer (12) abuts against the diffuser secondary blade (2).

6. The diffuser of the micro turbojet engine according to claim 1, characterized in that: The diffuser assembly is located on the front surface of the mounting plate (1). The diffuser assembly includes a main oil line connector through hole (4), an intake cap locking screw hole (5), an ignition line connector through hole (6), a diffuser locking screw hole (7), a bearing sleeve fixing step (8), and a diffuser primary blade (3). The front surface of the mounting plate (1) is provided with a main oil line connector through hole (4), an intake cap locking screw hole (5), and an ignition line connector through hole (6). The front surface of the mounting plate (1) is provided with a plurality of diffuser primary blades (3). The front surface of the mounting plate (1) is provided with a bearing sleeve fixing step (8). The inner surface of the bearing sleeve fixing step (8) is provided with a diffuser locking screw hole (7).

7. The diffuser of the micro turbojet engine according to claim 6, characterized in that: The main oil line connector through hole (4), the intake cover locking screw hole (5) and the ignition line connector through hole (6) all extend to the front surface of the primary diffuser blade (3), the secondary diffuser blade (2) is located on the outer surface of the mounting plate (1), and the bearing sleeve fixing step (8) is located in the middle of the front surface of the mounting plate (1).

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