CN112096522A - Hard-connected starter-generating system for micro-turbojet engine - Google Patents

Abstract

The invention belongs to the technical field of micro turbojet engines, and particularly relates to a hard connection starting power generation system of a micro turbojet engine, which comprises a starting generator, wherein a coupling male head is arranged at the connecting end of a rotating shaft of the starting generator, a coupling female head is arranged at the connecting end of a driving shaft of a turbine engine, a connecting groove is arranged at the connecting end of the coupling female head, a coupling pin buckle is arranged in the connecting groove, a connecting head arranged at the connecting end of the coupling male head is inserted into the connecting groove, a coupling pin is arranged on the connecting head, the coupling pin is inserted into the coupling pin buckle and is fixed through a pin locking screw, and the coupling pin is vertical to the central line of the rotating shaft of the starting generator; the system also comprises a preheating fuel system for cooling the motor, which is arranged on the starter generator. The invention reduces the occupation of the installation space of the turbojet engine; bidirectional transmission is realized between the motor and the engine rotor, and vibration caused by non-concentricity is greatly reduced; the temperature of the motor is effectively controlled, and the service life of the motor is prolonged.

Description

Hard-connected starter-generating system for micro-turbojet engine

technical field

The invention belongs to the technical field of micro-turbojet engines, and in particular relates to a hard-connected starter and power generation system for a micro-turbojet engine.

Background technique

In recent years, the rapid development of unmanned aerial vehicles and small aerial vehicles has also promoted the development of micro-turbojet engines. Micro turbojet engines are currently mostly used in small UAVs, target drones or missiles and other aircraft. During the working process of the motor mounted on the micro turbojet engine, a part of the loss will be converted into heat. This part of the heat will cause the temperature rise of the motor, which will affect the service life of the motor, and even affect the normal use of the motor.

The overall structure of the micro-turbojet engine has strict restrictions on the volume and weight of its components, and the commonly used air-cooling and water-cooling methods are not suitable for application in the micro-turbojet motor. Therefore existing motors have a short life due to lack of cooling.

At the same time, when the micro-turbine engine is started, the starter motor installed at the front end of the engine drives the rotor part to rotate to a certain speed, and the engine is fuel-injected and ignited to start. After the start is successful, the engine rotor part is separated from the starter motor. The existing clutch structure can only drive the rotor of the micro-turbojet engine unidirectionally by the motor, and the engine cannot drive the motor; and the existing clutch structure has a certain degree of misalignment between the motor shaft and the engine shaft, which produces a similar effect to the rotor. Bending unbalanced vibration, the existing clutch structure is used for the connection between the existing micro turbojet engine and the starter generator, and the measured maximum vibration acceleration is 20g; when the existing coupling male and female are connected, the motor bearing and The engine rotor bearings all generate large invalid axial loads, which affect the service life of the bearings, thereby shortening the engine maintenance cycle and overall life.

SUMMARY OF THE INVENTION

The purpose of the present invention is to avoid the defects of the prior art and provide a hard-connected starter and power generation system for a micro-turbojet engine, so as to solve the problem of the large volume, high power consumption, complex structure and high cost of the fuel preheating system in the prior art , The cooling effect is not ideal, which leads to the short life of the motor.

In order to achieve the above purpose, the technical solution adopted in the present invention is: a micro-turbojet engine hard-connected starter and power generation system, including a starter generator, the starter generator is at the front end of the micro-turbojet engine, the starter generator rotating shaft and the turbine. The drive shaft of the engine is coaxially arranged, the connecting end of the rotating shaft of the generator is equipped with a coupling male head, the connecting end of the driving shaft of the turbine engine is equipped with a coupling female head, and the connecting end of the coupling female head is installed There is a connecting groove in the connecting groove, a coupling pin buckle is arranged in the connecting groove, a connecting head provided at the connecting end of the coupling male head is inserted into the connecting groove, and a coupling pin is arranged on the connecting head, The coupling pin is inserted into the coupling pin buckle and fixed by a pin locking screw, and the coupling pin is perpendicular to the center line of the rotating shaft of the generator; it also includes a cooling motor installed on the generator Preheat the fuel system. The existing starter motor does not have the function of generating electricity. According to the needs of the aircraft, the present invention replaces the starter motor with a starter generator. After the start is successful, the rotor part of the micro-turbojet engine drives the starter generator to generate electricity, so as to provide electric energy of a certain power to the aircraft. , reduce battery load and improve engine efficiency.

Further, the cooling motor preheating fuel system includes a motor housing, the motor housing is sleeved on the motor through the motor housing bracket, the motor gland is installed on the open end of the motor housing, and the motor gland is provided with heat dissipation through holes; An oil inlet pipe and an oil outlet pipe are arranged on the motor shell bracket, the oil inlet pipe joint of the oil inlet pipe is provided with an oil inlet pipe joint, and the oil outlet pipe mouth of the oil outlet pipe is provided with an oil outlet pipe joint; the fuel enters the oil inlet pipe from the oil inlet pipe joint , and enter the cavity formed by the motor, the motor casing and the motor casing bracket through the oil inlet pipe, and then flow out from the oil outlet pipe joint and enter the engine for combustion. The present invention continuously transfers heat through the motor casing and the surrounding medium, and this process of dissipating heat is called motor cooling.

Further, the motor housing bracket includes an upper support foot and a lower support foot, the oil inlet pipe is an oil inlet channel arranged in the upper support foot, and the oil outlet pipe is an oil outlet arranged in the lower support foot. The oil inlet pipe joint and the oil outlet pipe joint are respectively arranged at the oil inlet of the oil inlet channel and the oil outlet of the oil outlet channel; the motor housing bracket is fixed on the engine air intake through the motor bracket fixing screws .

Further, the motor gland is in the shape of a disk; the heat dissipation through holes are uniformly distributed in the circumferential direction at the center position of the motor gland.

Further, a first sealing ring is arranged on the connection surface between the motor casing and the motor; a second sealing ring is arranged on the connection surface between the motor casing and the motor casing bracket; A third sealing ring is arranged on the connecting surface of the motor.

Further, the compressor provided in the turbine engine is provided with a rotational speed induction magnetic ring on the end face of the coupling female head between the coupling female head and the compressor, which provides a sampling frequency for the rotational speed sensor and the rotational speed sensor. Set on the outer wall of the intake duct.

Further, the coupling pin buckle is pressed in the connecting groove by the pressure plate, and the pressure plate is fixed with a fixing screw; the coupling male head is fixed on the rotating shaft end of the generator through the coupling locking screw. department.

Further, the concentricity between the male head of the coupling and the female head of the coupling is 0.01-0.05 mm; the matching clearance between the coupling pin and the coupling pin buckle is 0.02-0.1 mm; the coupling male head and the coupling After the female head is assembled, the axial displacement space is plus or minus 1mm.

Further, at least one motor wire is drawn out from the motor stator coil of the motor, and passes through the hole on the back cover of the motor, and is connected to the built-in circuit board of the engine through the engine air intake from below the motor bracket. .

Further, the motor is a three-phase brushless motor, and three motor wires are drawn out from the stator coil of the motor.

The beneficial effects of the present invention are:

1. The present invention combines the starter and generator of the miniature turbojet engine to realize the integration of starting and power generation, and reduces the installation space occupied by the turbojet engine; when the present invention works, it can realize two-way between the motor and the engine rotor. Transmission, so that the motor can realize the function of power generation; due to the small contact point, the force is uniform, and the vibration caused by the non-concentricity is greatly reduced;

2. No axial force is generated between the male and female heads of the coupling, and there is no invalid axial load, which has no effect on the maintenance cycle and overall life of the engine, and the vibration acceleration value can be reduced from 20g using the existing coupling to 4~ 5g; Solve the problems that the existing coupling technology can only transmit torque in one direction, the vibration is large and the axial force is adverse to the bearing;

3. The invention supports the long-term high-power power generation of the micro-turbojet engine, and the maximum power generation power exceeds 1000 watts;

4. There is a fuel cavity between the motor and the motor casing. When the motor generates electricity, the heat generated by the motor is used to preheat the fuel in the cavity, and the fuel can take away the heat from the fuel to reduce the working temperature of the motor; the motor is effectively used. Its own heat does not consume the electric energy of the on-board power supply, and it effectively controls the motor temperature and prolongs the life of the motor.

Description of drawings

Fig. 1 is the structural representation of the present invention;

Fig. 2 is the position schematic diagram of enlarged sealing ring of the present invention;

FIG. 3 is a left-view structural schematic diagram of the present invention.

Fig. 4 is the sectional structure schematic diagram of the present invention;

Fig. 5 is the top sectional structure schematic diagram of the present invention;

Fig. 6 is the left side view structure diagram of the coupling female head of the present invention;

Fig. 7 is the structural representation of the present invention;

FIG. 8 is a schematic structural diagram of the present invention.

Detailed ways

The principles and features of the present invention will be described below with reference to the accompanying drawings. The examples are only used to explain the present invention, but not to limit the scope of the present invention.

Embodiment 1, as shown in Figures 1-8, a hard-connected starter and power generation system for a micro turbojet engine, including a starter generator 4, the starter generator 4 is at the front end of the micro turbojet engine, and the starter generator rotating shaft 14. It is arranged coaxially with the drive shaft 15 of the turbine engine, the coupling male head 16 is installed on the connecting end of the rotating shaft 14 of the generator, and the coupling female head 17 is installed at the connecting end of the driving shaft 15 of the turbine engine. The connecting end of the coupling female head 17 is provided with a connecting groove, a coupling pin 18 is provided in the connecting groove, and the connecting head provided at the connecting end of the coupling male head 16 is inserted into the connecting groove. The coupling head is provided with a coupling pin 19. The coupling pin 19 is inserted into the coupling pin buckle 18 and fixed by a pin locking screw 20. The coupling pin 20 is connected to the rotating shaft of the generator. The center line of 14 is vertical; it also includes a cooling motor preheating fuel system installed on the generator generator 4.

The compressor 25 provided in the turbine engine is provided with a rotational speed induction magnetic ring 24 on the end face of the coupling female head 17 between the coupling female head 17 and the compressor 25 . The coupling pin buckle 18 is pressed into the connecting groove by the pressing plate 21 , and the pressing plate 21 is fixed by the fixing screw 22 . The coupling male head 16 is fixed on the end of the generator rotating shaft 14 through the coupling locking screw 23 . The concentricity between the coupling male head 16 and the coupling female head 17 is 0.01-0.05 mm, and the matching clearance between the coupling pin 5 and the coupling pin buckle 8 is 0.02-0.1 mm. After the coupling male head 1 and the coupling female head 4 are assembled, the axial displacement space is plus or minus 1 mm.

The cooling motor preheating fuel system includes a motor housing 3, which is sheathed on the generator 4 through a motor housing bracket 7, and a motor gland 1 is installed on the open end of the motor housing 3, on the motor gland 1. There is a heat dissipation through hole 13; an oil inlet pipe and an oil outlet pipe are arranged on the motor shell bracket 7, the oil inlet pipe joint of the oil inlet pipe is provided with an oil inlet pipe joint 8, and the oil outlet pipe mouth of the oil outlet pipe is provided with an oil outlet pipe joint 12; The fuel enters the oil inlet pipe from the oil inlet pipe joint, and enters the cavity formed by the starter generator 4, the motor casing 3 and the motor casing bracket 7 through the oil inlet pipe, and then flows out from the oil outlet pipe joint 12 and enters the engine for combustion.

The motor housing bracket 7 includes an upper support foot and a lower support foot, the oil inlet pipe is an oil inlet channel arranged in the upper support foot, and the oil outlet pipe is an oil outlet channel arranged in the lower support foot, The oil inlet pipe joint 8 and the oil outlet pipe joint 12 are respectively arranged at the oil inlet of the oil inlet channel and the oil outlet of the oil outlet channel. The motor housing bracket 7 is fixed on the engine air intake 11 by the motor bracket fixing screws 9 . A first sealing ring 2 is provided on the connecting surface of the motor casing 3 and the generator 4 . A second sealing ring 5 is provided on the connecting surface of the motor housing 3 and the motor housing bracket 7 . A third sealing ring 6 is provided on the connecting surface of the motor housing bracket 7 and the generator 4 .

At least one motor wire 10 is drawn out from the motor stator coil of the generator generator 4, and is passed through the hole on the motor rear cover 1, and is connected to the built-in engine through the engine air intake from below the motor bracket 7. on the circuit board. The generator 4 is a three-phase brushless motor, and three motor wires 10 are drawn out from the stator coil of the motor.

When the engine is working, the motor temperature rises to about 110°C, the engine fuel enters the cavity formed by the starter generator 4, the motor casing 3 and the motor casing bracket 7 from the fuel inlet pipe joint 8, and then the fuel flows out from the fuel outlet pipe joint 12. Combustion inside the engine, when the engine fuel flows out, it takes away the excess heat generated when the motor works, thus achieving the effect of preheating the fuel and cooling the motor.

At the same time, during the engine starting process of the present invention, the generator rotating shaft 14 drives the coupling male head 16 to rotate, the coupling male head 16 drives the coupling female head 17 to rotate, and the coupling female head 17 drives the turbine engine. The rotation of the drive shaft 15 finally makes the engine reach the ignition speed. After the combustion chamber of the engine is successfully ignited, the engine reaches the self-sustaining speed, that is, the minimum idle speed. At this time, the motor no longer needs to output torque. When the engine speed is greater than the minimum idle speed, the drive shaft 15 of the turbine engine drives the coupling female head 17 to rotate, the coupling female head 17 drives the coupling male head 16 to rotate, and the coupling male head 16 drives the generator. Rotate the shaft 14 so that the electric motor can provide power output. At the same time, since there is no axial contact between the drive shaft 15 of the turbine engine and the generator rotating shaft 14 of the present invention, only torque can be transmitted between the two, but no axial force can be transmitted, which solves the problem of the existing coupling technology. Only one-way torque transmission, large vibration and unfavorable axial force on the bearing are caused.

Example 2: Same as Example 1, the difference is: the motor gland 1 is disc-shaped; the heat dissipation through holes are evenly distributed in the circumferential direction at the center position of the motor gland 3-10.

In order to limit the present invention, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. A micro turbojet engine hard connection starting power generation system comprises a generator, wherein the generator is arranged at the front end of the micro turbojet engine, and a generator rotating shaft and a drive shaft of a turbine engine are coaxially arranged; the system also comprises a preheating fuel system for cooling the motor, which is arranged on the starter generator.

2. The system of claim 1, wherein the cooling motor preheating fuel system comprises a motor housing, the motor housing is sleeved on the motor through a motor housing bracket, a motor gland is installed at an opening end of the motor housing, and a heat dissipation through hole is formed in the motor gland; an oil inlet pipe and an oil outlet pipe are arranged on the motor shell bracket, an oil inlet pipe joint is arranged at an oil inlet pipe orifice of the oil inlet pipe, and an oil outlet pipe joint is arranged at an oil outlet pipe orifice of the oil outlet pipe; fuel enters the oil inlet pipe from the oil inlet pipe joint and enters a cavity formed by the motor, the motor shell and the motor shell bracket through the oil inlet pipe, and then flows out from the oil outlet pipe joint and enters the engine for internal combustion.

3. The micro turbojet engine hard connection starting power generation system of claim 2, wherein the motor casing support comprises an upper support leg and a lower support leg, the oil inlet pipe is an oil inlet channel arranged in the upper support leg, the oil outlet pipe is an oil outlet channel arranged in the lower support leg, and the oil inlet pipe joint and the oil outlet pipe joint are respectively arranged at an oil inlet of the oil inlet channel and an oil outlet of the oil outlet channel; the motor casing support is fixed on an engine air inlet channel through a motor support fixing screw.

4. The micro turbojet engine hard-wired start-up power generation system of claim 2 wherein the motor gland is disc-shaped; 3-10 radiating through holes are uniformly distributed in the circumferential direction at the central position of the motor gland.

5. The micro turbojet engine hard-link start-up power generation system of claim 2 wherein a first seal ring is provided on the connection surface of the motor housing and the motor; a second sealing ring is arranged on the connecting surface of the motor shell and the motor shell bracket; and a third sealing ring is arranged on the connecting surface of the motor shell bracket and the motor.

6. The system as claimed in claim 1, wherein the turbine engine is provided with a compressor, and a rotation speed induction magnet ring is disposed on an end surface of the coupling female head between the coupling female head and the compressor.

7. The micro turbojet engine hard-link start-up power generation system of claim 1 wherein the coupling pin is pressed in the connection groove by the pressure plate and the pressure plate is fixed by the fixing screw; and the male head of the coupler is fixed at the end part of the rotating shaft of the generator through a coupler locking screw.

8. The micro turbojet engine hard-link start-up power generation system of claim 1 wherein the concentricity of the male coupling head and the female coupling head is 0.01 to 0.05 mm; the fit clearance between the coupling pin and the coupling pin buckle is 0.02-0.1 mm; the axial displacement space is plus or minus 1mm after the male coupling head and the female coupling head are assembled.

9. The system according to any one of claims 1 to 8, wherein at least one motor wire is led out from a motor stator coil of the motor, and is led out from a hole on a motor rear cover, and is connected to the internal circuit board of the engine through an engine air inlet below the motor bracket.

10. The system according to claim 9, wherein the motor is a three-phase brushless motor, and three motor wires are led out from a stator coil of the motor.

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