Lubricating structure for gear shaft and spline bearing of fuel pump of aircraft engine accessory casing
By employing an oil passage shaft and adapter ring structure in the aircraft engine accessory housing, and designing bearing lubrication channels and oil collection grooves, the lubrication problem of the fuel pump gear shaft was solved, enabling separate lubrication of splines and bearings, simplifying the machining process, and ensuring lubrication effect.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- AECC SHENYANG ENGINE RES INST
- Filing Date
- 2026-03-06
- Publication Date
- 2026-04-21
AI Technical Summary
In the accessory housing of an aircraft engine, it is difficult to achieve separate lubrication for the splines and bearings of the fuel pump gear shaft, and increasing the number of injection points will affect the internal structure and oil passage layout of the housing.
It adopts an oil-passing shaft and adapter ring structure, and through the bearing lubrication channel and annular oil collection groove design on the gear shaft, it realizes the centrifugal distribution of lubricating oil, and lubricates the spline and bearing separately, avoiding the addition of new spray points.
It enables separate lubrication of splines and bearings, simplifies the machining process, does not affect the internal space of the casing and the oil circuit layout, and ensures the lubrication effect.
Smart Images
Figure CN121897670A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the technical field of aircraft engine accessory housing structure design, specifically relating to a lubrication structure for a fuel pump gear shaft spline bearing in an aircraft engine accessory housing. Background Technology
[0002] The aircraft engine accessory housing is compact and highly integrated, providing a reliable and stable power source for all aircraft and engine accessories. The gears and bearings inside the accessory housing are lubricated by oil mist, and the oil supply lines are integrated inside the accessory housing shell, ultimately supplying oil to the shell through an oil supply injector.
[0003] The fuel pump is one of the core components of an engine, connected to a gear shaft via a spline. Compared to other components, the fuel pump is heavier and has a higher rated power. To ensure its safe and stable operation, a good lubrication environment must be provided for the spline. Furthermore, a bearing is located at the end of the fuel pump gear shaft furthest from the fuel pump. This bearing bears a significant load and requires an additional lubrication path on top of oil mist lubrication to ensure its reliable operation.
[0004] Currently, for engine fuel pump gear shafts, the common approach is to add oil lines and injection points to provide separate lubrication for the splines and bearings. However, given the overall internal layout of the accessory housing, adding a separate oil injection point at the spline connection between the fuel pump and the gear shaft is quite difficult. Furthermore, the limited space and compact structure of the housing leave no space for pre-installed bearing injection points. Adding injection points for separate bearing lubrication would interfere with the gear shaft, disrupt the existing oil line layout within the housing, affect the overall structure of the accessory housing, and impact the installation method of related accessories and the arrangement of external pipelines.
[0005] In view of the aforementioned technical deficiencies, this application is hereby filed. Summary of the Invention
[0006] The purpose of this application is to provide a lubrication structure for the spline bearing of the fuel pump gear shaft in an aircraft engine accessory casing, in order to overcome or mitigate at least one of the known technical defects.
[0007] The technical solution of this application is:
[0008] A lubrication structure for a spline bearing of a fuel pump gear shaft in an aircraft engine accessory casing includes an oil passage shaft and a transition ring.
[0009] The oil passage shaft is a hollow shaft, which is installed inside the gear shaft at one end. A bearing is sleeved on this end of the gear shaft, and the bearing is located on the outside of the gear. A spline is installed inside the other end of the gear shaft.
[0010] The gear shaft has multiple bearing lubrication channels distributed circumferentially. Each bearing lubrication channel connects the part between the bearing and the gear, and each bearing lubrication channel is inclined towards the bearing.
[0011] The adapter ring is sleeved on the oil-conducting shaft and connected to the inside of the gear shaft;
[0012] The end of the adapter ring facing the spline has an annular oil collection groove, and an annular oil collection cavity is formed between the adapter ring and the gear shaft. The annular oil collection groove and the annular oil collection cavity are connected by multiple oil passages distributed along the axial direction, and the annular oil collection cavity is connected to the lubrication channels of each bearing.
[0013] According to at least one embodiment of this application, in the above-described lubrication structure for the spline bearing of the fuel pump gear shaft of the aircraft engine accessory casing, the angle of inclination of each bearing lubrication channel toward the bearing direction is 15° to 30°.
[0014] According to at least one embodiment of this application, in the above-described lubrication structure for the fuel pump gear shaft spline bearing of the aircraft engine accessory casing, the transition ring is integrally formed on the oil passage shaft.
[0015] According to at least one embodiment of this application, in the above-described lubrication structure for the spline bearing of the fuel pump gear shaft in the aircraft engine accessory casing, the transition ring is interference-fitted to the inner side of the gear shaft.
[0016] According to at least one embodiment of this application, in the above-described lubrication structure of the fuel pump gear shaft spline bearing in the aircraft engine accessory casing, there are ten oil passages and bearing lubrication channels, which are staggered in the circumferential direction.
[0017] This application has at least the following beneficial technical effects:
[0018] A lubrication structure for the fuel pump gear shaft spline bearing in an aircraft engine accessory housing is provided. The structure is simple in principle and easy to process. It can simultaneously lubricate the spline and bearing separately through a single oil supply, without the need for additional oil supply points and without affecting the internal space layout and oil circuit layout of the accessory housing. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the lubrication structure of the fuel pump gear shaft spline bearing in the aircraft engine accessory housing provided in this application embodiment;
[0020] Figure 2 This is an end view of the lubrication structure of the fuel pump gear shaft spline bearing in the aircraft engine accessory housing provided in this application embodiment;
[0021] Figure 3 yes Figure 2 AA view;
[0022] Figure 4This is an installation schematic diagram of the lubrication structure for the fuel pump gear shaft spline bearing in the aircraft engine accessory housing provided in this application embodiment;
[0023] Figure 5 This is a schematic diagram of the working operation of the lubrication structure of the fuel pump gear shaft spline bearing in the aircraft engine accessory housing provided in this application embodiment;
[0024] in:
[0025] 1-Oil passage shaft; 2-Adapter ring; 3-Gear shaft; 4-Gear; 5-Bearing.
[0026] To better illustrate this embodiment, some content in the accompanying drawings may be omitted, enlarged, or reduced. They are for illustrative purposes only and should not be construed as limiting the scope of this application. Detailed Implementation
[0027] To make the technical solution and advantages of this application clearer, the technical solution of this application will be described in a clearer and more complete manner below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of this application, and are only used to explain this application, not to limit this application. It should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings, and other related parts can be referred to the general design.
[0028] Furthermore, unless otherwise defined, the technical or scientific terms used in this application description shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The word "comprising" as used in this application description indicates that the concept preceding the word encompasses the concepts listed following the word and their equivalents, without excluding other related concepts.
[0029] Furthermore, the terms indicating location used in the description of this application are only used to indicate relative directions or positional relationships. When the absolute position of the described object changes, its relative positional relationship may also change accordingly. It should also be noted that, unless otherwise explicitly specified and limited, terms such as "installation" and "connection" used in the description of this application should be interpreted broadly. For example, a connection can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand its specific meaning in this application according to the specific circumstances.
[0030] This application provides a lubrication structure for the spline bearing of the fuel pump gear shaft in an aircraft engine accessory casing. This structure is a centrifugal oil-throwing mechanism that can simultaneously lubricate the spline and bearing under high-speed rotation. Figures 1-3 As shown, it includes an oil passage shaft 1 and an adapter ring 2.
[0031] The oil passage shaft 1 is a hollow shaft, located inside one end of the gear shaft 3 where the gear 4 is mounted. A bearing 5 is sleeved on this end of the gear shaft 3, with the bearing 5 located outside the gear 4. A spline 6 is located inside the other end of the gear shaft 3. Figure 4 As shown.
[0032] The gear shaft 3 has multiple bearing lubrication channels distributed circumferentially. Each bearing lubrication channel connects the part between the bearing 5 and the gear 4, and each bearing lubrication channel is inclined towards the bearing 5 at an angle of 15° to 30°.
[0033] The adapter ring 2 is sleeved on the oil passage shaft 1, and can be integrally formed on the oil passage shaft 1. It is connected to the inner side of the gear shaft 3, and can be interference-fitted.
[0034] The end of the adapter ring 2 facing the spline 6 has an annular oil collection groove. An annular oil collection cavity is formed between the adapter ring 2 and the gear shaft 3. The annular oil collection groove and the annular oil collection cavity are connected by multiple oil passage holes distributed along the axial direction. The annular oil collection cavity is connected to each bearing lubrication channel. The number of oil passage holes and bearing lubrication channels can be designed to be ten, and they are staggered in the circumferential direction.
[0035] When the lubrication structure for the fuel pump gear shaft spline bearing of the aircraft engine accessory casing disclosed in the above embodiments is working, lubricating oil can be introduced into the gear shaft 3 through the oil passage shaft 1. Under the action of centrifugal force, the lubricating oil is divided into two paths. One path flows along the oil passage shaft 1 to the spline 6 to lubricate the spline 6. The other path enters the annular oil collecting groove, and then enters the annular oil collecting cavity through the oil passage hole. It accumulates in the annular oil collecting cavity and finally flows through the bearing lubrication channel to the part between the bearing 5 and the gear 4 to lubricate the bearing 5. Figure 5 As shown.
[0036] The lubrication structure for the fuel pump gear shaft spline bearing in the aircraft engine accessory housing disclosed in the above embodiments has a simple structure and is easy to process. It can simultaneously lubricate the spline 6 and the bearing 4 separately through one oil supply, without the need to add oil supply points and without affecting the internal spatial layout and oil circuit layout of the accessory housing.
[0037] The technical solution of this application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of this application.
Claims
1. A lubrication structure for the spline bearing of the fuel pump gear shaft in an aircraft engine accessory casing, characterized in that, Includes oil passage shaft (1) and adapter ring (2); The oil passage shaft (1) is a hollow shaft. It is installed inside one end of the gear shaft (3) where the gear (4) is located. A bearing (5) is sleeved on this end of the gear shaft (3). The bearing (5) is located outside the gear (4). A spline (6) is installed inside the other end of the gear shaft (3). The gear shaft (3) has multiple bearing lubrication channels distributed circumferentially. Each bearing lubrication channel connects the part between the bearing (5) and the gear (4), and each bearing lubrication channel is inclined towards the bearing (5). The adapter ring (2) is sleeved on the oil-conducting shaft (1) and connected to the inside of the gear shaft (3); The end of the adapter ring (2) facing the spline (6) has an annular oil collection groove. An annular oil collection cavity is formed between the adapter ring (2) and the gear shaft (3). The annular oil collection groove and the annular oil collection cavity are connected by multiple oil passages distributed along the axial direction, and the annular oil collection cavity is connected to each bearing lubrication channel.
2. The lubrication structure for the fuel pump gear shaft spline bearing in the aircraft engine accessory housing according to claim 1, characterized in that, The angle of inclination of each bearing lubrication channel toward the bearing (5) is 15°~30°.
3. The lubrication structure for the fuel pump gear shaft spline bearing in the aircraft engine accessory housing according to claim 2, characterized in that, The adapter ring (2) is integrally formed on the oil-conducting shaft (1).
4. The lubrication structure for the fuel pump gear shaft spline bearing in the aircraft engine accessory housing according to claim 3, characterized in that, The adapter ring (2) is interference-fitted to the inside of the gear shaft (3).
5. The lubrication structure for the fuel pump gear shaft spline bearing in the aircraft engine accessory housing according to claim 4, characterized in that, There are ten oil passages and bearing lubrication channels, which are staggered in the circumferential direction.