An engine automatic cranking device after parking

Abstract

The application provides an automatic rotating device after engine parking, and belongs to the technical field of ground bench test and maintenance equipment of an aero-engine, and specifically comprises a motor with a speed reducer, a speed reduction assembly, a one-way clutch and a driving shaft; the motor is connected with an input shaft of the one-way clutch through the speed reduction assembly, an output shaft of the one-way clutch is connected with the driving shaft, and the driving shaft is fixedly connected with a standby transmission shaft of the engine; the output rotating speed of the motor is 500-700 r / min, the speed reduction ratio of the speed reduction assembly is greater than 100, the rotating speed of the driving shaft is 1.5-8 r / min, the output torque of the driving shaft is not less than 35 N.m, the power of the motor is not greater than 80 W, and the input voltage is not greater than 30 V. Through the processing scheme, uniform cooling of a high-pressure compressor rotor is ensured, and vibration when the engine restarts is reduced.

Description

Technical Field

[0001] This application relates to the field of ground test bench maintenance equipment for aircraft engines, and in particular to an automatic cranking device after an engine stops. Background Technology

[0002] Early multi-stage gas turbines or general industrial gas turbines, due to their numerous rotor stages and relatively heavy structure, experienced long cooling times for internal components, especially the rotor discs, after shutdown. During the cooling process, the rising of hot gas and the sinking of cold gas within the rotor create a temperature difference between the upper and lower parts of the rotor structure, leading to uneven thermal expansion and bending deformation. Theoretically, this deformation should disappear on its own as the temperature becomes more uniform after the engine has fully cooled down. However, in some structurally heavy industrial gas turbines, the prolonged cooling time and structural factors can result in residual permanent deformation. If the unit is restarted in this state, it will generate significant vibration. For units without residual deformation or aero gas turbine engines, starting them shortly after shutdown before they have fully cooled down—a so-called hot start—can cause temporary uneven heating of the rotor, leading to bending and deformation, increasing rotor imbalance, and resulting in significant vibration. Summary of the Invention

[0003] In view of this, this application provides an automatic cranking device after the engine stops, which solves the problems in the prior art, ensures uniform cooling of the high-pressure compressor rotor, and reduces vibration when the engine restarts.

[0004] The automatic cranking device after engine shutdown provided in this application adopts the following technical solution:

[0005] An automatic cranking device after engine shutdown includes a motor with a reducer, a reduction assembly, a one-way clutch, and a drive shaft;

[0006] The motor drives the input shaft of the one-way clutch through a reduction assembly. The output shaft of the one-way clutch is connected to the drive shaft, and the drive shaft is fixedly connected to the engine's spare transmission shaft.

[0007] The output speed of the motor is 500-700 r / min, the reduction ratio of the reduction assembly is greater than 100, the speed of the drive shaft is 1.5-8 r / min, the output torque of the drive shaft is not less than 35 N·m, the power of the motor is not greater than 80 W, and the input voltage is not greater than 30 V.

[0008] Optionally, the automatic cranking device after the engine stops also includes a mounting housing, one end of which is fixedly connected to the engine spare transmission seat, and the other end of which is fixedly connected to the housing of the reduction assembly. The drive shaft is rotatably mounted inside the mounting housing via bearings, and the one-way clutch is located inside the mounting housing.

[0009] Optionally, the bottom of the mounting housing is provided with an oil outlet, which is used to connect to an oil return line or a sealing bolt.

[0010] Optionally, the input shaft of the one-way clutch has a neck region with a reduced diameter, forming a mechanically weak point.

[0011] Optionally, the reduction assembly package consists of multiple planetary gear reduction units connected in series.

[0012] Optionally, two adjacent planetary gear reduction units in the reduction assembly are connected by a right-angle transmission structure;

[0013] The axial directions of the output shaft, drive shaft, and one-way clutch of the reduction assembly are parallel to the axial direction of the engine's spare drive shaft.

[0014] The output shaft of the reduction assembly and the axial direction of the motor are perpendicular to the axial direction of the spare transmission shaft.

[0015] Optionally, the automatic cranking device after the engine stops also includes a control component, which is electrically connected to the motor and controls the motor to stop working for 5 minutes after every 2 minutes of continuous operation.

[0016] Optionally, the length of the automatic cranking device after the engine stops, both in the direction parallel to the drive shaft axis and in the direction parallel to the motor axis, is less than 250mm.

[0017] The diameter of the automatic cranking device after the engine stops, both in the direction parallel to the drive shaft axis and in the direction parallel to the motor axis, is less than 120mm.

[0018] In summary, this application includes the following beneficial technical effects:

[0019] The automatic engine cranking device of this application is lightweight, easy to install, disassemble, and use. It meets the requirements for cranking and uniform cooling when the engine needs to be parked after shutdown during bench testing of a certain type of engine, improving upon the current manual cranking method which is labor-intensive and uneven. It effectively reduces excessive vibration during engine testing caused by uneven cooling after engine shutdown, resulting in excessive vibration during hot starts and before full warm-up. This device is also suitable for field use, preventing situations where excessive vibration necessitates sufficient engine cooling before aircraft takeoff due to incomplete engine cooling, thus avoiding prolonged sortie times and impacting mission execution. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the overall structure of the automatic cranking device after the engine stops.

[0022] Explanation of reference numerals in the attached drawings: 1. Motor; 2. Reduction assembly; 3. One-way clutch; 4. Drive shaft; 5. Mounting housing; 6. Bearing; 7. Oil outlet; 71. Sealing bolt; 8. Engine spare drive shaft; 9. Engine spare drive seat. Detailed Implementation

[0023] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0024] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this application, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0026] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this application. The illustrations only show the components related to this application and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0027] Furthermore, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that the described aspects can be practiced without these specific details.

[0028] This application provides an automatic cranking device after the engine stops.

[0029] like Figure 1 As shown, an automatic cranking device after the engine stops includes a motor 1 with a reducer, a reduction assembly 2, a one-way clutch 3, and a drive shaft 4.

[0030] The motor 1 drives the input shaft of the one-way clutch 3 via the reduction gear assembly 2. The output shaft of the one-way clutch 3 is connected to the drive shaft 4, and the drive shaft 4 is fixedly connected to the engine's spare transmission shaft 8. The motor 1 drives the input shaft of the one-way clutch 3 to rotate via the reduction gear assembly 2.

[0031] The output speed of the motor 1 is 500-700 r / min, the reduction ratio of the reduction assembly 2 is greater than 100, the speed of the drive shaft 4 is 1.5-8 r / min, the output torque of the drive shaft 4 is not less than 35 N·m, the power of the motor 1 is not greater than 80 W, and the input voltage is not greater than 30 V. In one embodiment, the one-way clutch 3 is a roller one-way clutch 3, the drive shaft 4 is a splined shaft, the engine spare transmission shaft 8 is provided with a splined sleeve that mates with the drive shaft 4, the output shaft of the drive shaft 4 and the one-way clutch 3 are connected by a key, and the input shaft of the one-way clutch 3 and the output shaft of the reducer are connected by a key.

[0032] The length of the automatic cranking device after engine shutdown, both in the axial direction parallel to drive shaft 4 and in the axial direction parallel to motor 1, is less than 250mm; the diameter of the automatic cranking device, both in the axial direction parallel to drive shaft 4 and in the axial direction parallel to motor 1, is less than 120mm. The maximum outline of the device and the outline of the electrical socket should not affect operation during engine testing, and should be as small and lightweight as possible while ensuring functionality.

[0033] The automatic cranking device of this application is installed on the engine during engine testing, meaning it only needs to be installed and removed once during normal engine testing, reducing disassembly and assembly work. The device uses a one-way transmission clutch to ensure that cranking can only be performed after the high-pressure rotor has stopped rotating. This application provides a small, lightweight, and portable electric automatic cranking device that ensures uniform cooling of the engine's high-pressure rotor, preventing deformation of internal structural components due to uneven heating and cooling after a hot start, which could lead to abnormally large vibrations during operation.

[0034] The automatic cranking device after engine shutdown also includes a control component, which is electrically connected to the motor 1. The control component controls the motor 1 to work continuously for 2 minutes and then stop for 5 minutes, thereby achieving cyclical control of the engine during shutdown, which involves continuous operation for 2 minutes followed by a 5-minute stop. In one embodiment, the control component is a PLC controller.

[0035] The automatic cranking device after engine shutdown also includes a mounting housing 5. One end of the mounting housing 5 is fixedly connected to the engine spare transmission housing, and the other end of the mounting housing 5 is fixedly connected to the housing of the reduction assembly 2. The drive shaft 4 is rotatably mounted inside the mounting housing 5 via a bearing 6, and the one-way clutch 3 is located inside the mounting housing 5. The mounting housing 5 is fixedly connected to the engine spare transmission housing by a clamp. Because the connection between the drive shaft 4 and the engine spare transmission shaft 8 does not completely seal the lubricating oil mist inside the engine spare transmission housing, the mounting housing 5 is used to prevent the lubricating oil mist from spreading.

[0036] Furthermore, an oil outlet 7 is provided at the bottom of the mounting housing 5, which is used to connect to the return oil line or the sealing bolt 71. The lubricating oil inside the mounting housing 5 can be drained to the rear transmission case of the engine through the return oil line. A filter screen can be installed at the inlet of the return oil line, or the lubricating oil accumulated inside the mounting housing 5 can be drained through the oil outlet 7 by disassembling the return oil line. When the engine stops and the automatic cranking device is in operation, the oil outlet 7 is sealed by the sealing bolt 71.

[0037] During engine operation, the output shafts of drive shaft 4 and one-way clutch 3 rotate with the engine, with a rotational speed range of 0-4250 r / min. Therefore, drive shaft 4 is mounted in mounting housing 5 via bearing 6.

[0038] The input shaft of the one-way clutch 3 has a neck area with a reduced diameter, forming a weak point in mechanical structure and a shearing design. This design is intended to prevent the input shaft of the one-way clutch 3 from breaking under abnormal conditions when it is driven by the output shaft of the one-way clutch 3. This prevents damage to the deceleration assembly 2 and other components from entering the rear transmission housing when the engine is running.

[0039] The reduction assembly 2 comprises multiple planetary gear reduction units connected in series. In one embodiment, two adjacent planetary gear reduction units in the reduction assembly 2 are connected by a right-angle transmission structure.

[0040] The axial directions of the output shaft, drive shaft 4, and one-way clutch 3 of the reduction assembly 2 are parallel to the axial direction of the engine backup transmission shaft 8; the axial directions of the output shaft and motor 1 of the reduction assembly 2 are perpendicular to the axial direction of the backup transmission shaft.

[0041] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An automatic cranking device after the engine stops, characterized in that, It includes a motor (1) with a speed reducer, a speed reduction assembly (2), a one-way clutch (3), and a drive shaft (4); The motor (1) is driven to the input shaft of the one-way clutch (3) via the reduction assembly (2). The output shaft of the one-way clutch (3) is connected to the drive shaft (4). The drive shaft (4) is fixedly connected to the engine spare transmission shaft (8). The output speed of the motor (1) is 500-700 r / min, the reduction ratio of the reduction assembly (2) is greater than 100, the speed of the drive shaft (4) is 1.5-8 r / min, the output torque of the drive shaft (4) is not less than 35 N.m, the power of the motor (1) is not greater than 80 W, and the input voltage is not greater than 30 V. The automatic cranking device after the engine stops also includes a mounting shell (5), one end of which is fixedly connected to the engine spare transmission seat, and the other end of which is fixedly connected to the housing of the reduction assembly (2). The drive shaft (4) is rotatably mounted in the mounting shell (5) via a bearing (6), and the one-way clutch (3) is located in the mounting shell (5). The deceleration assembly (2) consists of multiple planetary gear reduction units connected in series; The two adjacent planetary gear reduction units in the reduction assembly (2) are connected by a right-angle transmission structure; The axial directions of the output shaft, drive shaft (4) and one-way clutch (3) of the reduction assembly (2) are parallel to the axial direction of the engine spare transmission shaft (8); The output shaft of the reduction assembly (2) and the axial direction of the motor (1) are perpendicular to the axial direction of the engine's spare drive shaft.

2. The automatic cranking device after engine shutdown according to claim 1, characterized in that, The mounting housing (5) has an oil outlet (7) at the bottom, which is used to connect the return oil pipeline or the sealing bolt (71).

3. The automatic cranking device after engine shutdown according to claim 1, characterized in that, The input shaft of the one-way clutch (3) has a neck region with a reduced diameter, forming a weak point in mechanical structure.

4. The automatic cranking device after engine shutdown according to claim 1, characterized in that, The automatic cranking device after the engine stops also includes a control component, which is electrically connected to the motor (1) and controls the motor (1) to run for 2 minutes of continuous operation followed by a 5-minute stop.

5. The automatic cranking device after engine shutdown according to claim 1, characterized in that, The length of the automatic rocking device after the engine stops is less than 250mm in both the axial direction parallel to the drive shaft (4) and the axial direction parallel to the motor (1). The diameter of the automatic cranking device after the engine stops is less than 120mm in both the axial direction parallel to the drive shaft (4) and the axial direction parallel to the motor (1).

Images