JP2001073875A - Super-high bypass ratio engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a low fuel consumption in a compact engine by introducing a super-high bypassing structure of engine. SOLUTION: A pinion 11 is attached to the tip of the shaft 6 of a gas generator 7 installed in an engine duct 1, and a large diametric fan 12 is installed under the pinion 11. The rotary shaft 13 of the fan 12 is supported rotatably by a frame 14 overhung from the engine duct 1. A ring-shaped externally cogged gear 15 having a large diameter is attached rigidily to the outer end of the fan 12. The gear 15 is meshed with the pinion 11, and a large-ratio speed reducing mechanism is formed. The gas generator 7 is rotated at a high speed, and the fan 12 is rotated at a low speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultra-high bypass ratio engine used as a commercial aircraft engine.

[0002]

2. Description of the Related Art As shown in FIGS. 2A and 2B, a high bypass ratio engine used as a commercial aircraft engine has a compressor 2 and a combustion engine in an engine duct 1 in order from the front end. Generator 3, a turbine 4, and a fan turbine 5 are arranged in the direction of the shaft 6, and a fan 8 is coaxially arranged in front of the gas generator 7, and the rotation of the gas generator 7 is planetary. In general, the speed is reduced by the mold gear mechanism 9 and transmitted to the fan 8 to reduce fuel consumption (high efficiency). Reference numeral 10 denotes a fan duct.

[0003]

However, in the case of the above-described high bypass ratio engine, in order to increase the propulsion efficiency of the fan 8, the outer diameter is increased to increase the mass of the fluid, and the ejection speed of the fluid is reduced to the machine speed. On the other hand, it is important to increase the compression ratio of the compressor 2 by rotating the gas generator 7 at the highest possible speed in order to achieve high efficiency, but the planetary gear mechanism 9
There is also a space restriction that the fan 8 is arranged in the mainstream of the gas generator 7, so that the reduction ratio of the fan 8 can be only about 3 to 4 at most. Is suitable for a large engine having a relatively small number of revolutions, but is not suitable for a small engine.

As described above, in order to achieve low fuel consumption (high efficiency), it is necessary to lower the speed of the fan 8 for generating thrust and to rotate the gas generator 7 for driving the fan 8 at a higher speed. It is necessary to satisfy the conflicting demands of the planetary gear mechanism 9 as described above.
It was difficult to achieve a sufficiently low fuel consumption with an engine that employs.

Accordingly, the present invention aims at achieving ultra-high bypass in a small engine capable of increasing the speed of the gas generator section without restriction on the blade tip speed, thereby achieving low fuel consumption. is there.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, a gear is attached to a tip end of a shaft of a gas generator provided in an engine duct, and the engine duct projects outward from the engine duct. The fan's rotating shaft so that it can rotate freely, and
A ring-shaped external gear is integrally attached to the outer periphery of the fan,
The ring-shaped external gear and the gear are meshed with each other to rotate a fan via the ring-shaped external gear, and the gear ratio between the gear and the ring-shaped external gear is set to 1. : 10 or more.

Even when the gas generator is rotated at a high speed, the fan rotates at a low speed because a small gear and a large-diameter ring-shaped external gear constitute a large ratio reduction mechanism. Therefore, the high-speed rotation of the gas generator and the low-speed rotation of the fan can be performed at the same time, and the fuel consumption of the engine can be reduced.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 (a) and 1 (b) show an embodiment of the present invention. In a configuration in which a gas generator 7 similar to that shown in FIG. A small gear (gear) 11 is attached to the tip of the shaft 6 of the gas generator 7 so that the small gear 11 can be rotated by the driving of the gas generator 7, while a support projecting from the outer wall of the engine duct 1. Frame 14
In addition, a rotating shaft 13 of a large fan 12 is rotatably supported, and a ring-shaped external gear 15 having a large diameter is integrally and concentrically provided with the rotating shaft 13 at the outer end of each blade 12 a of the fan 12. In addition, the ring-shaped external gear 15 and the small gear 11 are meshed with each other, and the small gear 11 is rotated at a high speed so that the fan 12 is rotated at a low speed via the ring-shaped external gear 15. I do.

The gear ratio between the small gear 11 and the large-diameter ring-shaped external gear 15 is selected to be 1:10 or more.

In the drawing, the same parts as those in FIG. 2A are denoted by the same reference numerals.

In the engine having the above-described configuration, the engine duct 1 is suspended from the wing 16 of an aircraft.

In the ultrahigh bypass ratio engine of the present invention, a ring-shaped external gear 15 having a large diameter is mounted on the outer diameter portion of the fan 12, which is mounted on the shaft 6 of the gas generator 7 and rotated by the small gear 11. Thus, if the small gear 11 is rotated and the fan 12 is rotated, a reduction ratio of a large ratio (10 or more) can be configured, and low fuel consumption can be achieved. That is,
Even if the gas generator 7 is rotated at a high speed, the small gear 1
The rotation speed of the fan 12 is reduced by a large reduction ratio of 1 and the ring-shaped external gear 15 having a large diameter to rotate the fan 12, so that the fan 12 for generating thrust can be rotated at a low speed.

Therefore, the low speed rotation of the fan 12 and the high speed rotation of the gas generator 7 for driving the fan 12 can be satisfied at the same time as a requirement necessary for achieving low fuel consumption. It is possible to achieve extremely low fuel consumption (high efficiency).

In the above embodiment, the aircraft wing 1
Although the case where the engine duct 1 is directly suspended from the position 6 is shown, the whole may be accommodated in a large frame, and various changes may be made without departing from the gist of the present invention. Of course.

[0016]

As described above, according to the ultrahigh bypass ratio engine of the present invention, a gear is attached to the tip of the shaft of the gas generator provided in the engine duct, and the gear is mounted on the engine duct outward. On the overhanging support frame, the fan's rotating shaft is rotatably supported,
Further, a ring-shaped external gear is integrally attached to the outer periphery of the fan, and the ring-shaped external gear is meshed with the gear,
The gear is configured to rotate the fan via the ring-shaped external gear, and the gear ratio between the gear and the ring-shaped external gear is set to 1:10 or more. In order to achieve high fuel consumption (high efficiency), it is possible to simultaneously satisfy the requirements of high-speed rotation of the gas generator and low-speed rotation of the fan,
Sufficient fuel consumption (high efficiency) can be achieved,
It has an excellent effect that ultra-high bypass can be achieved with a small engine.

[Brief description of the drawings]

FIG. 1 shows an embodiment of an ultra-high bypass ratio engine of the present invention, in which (A) is a schematic side view of the whole, and (B) is a view taken in the direction of arrows AA in (A).

FIGS. 2A and 2B show an example of a conventional high bypass ratio engine, wherein FIG. 2A is a schematic side view, and FIG.

[Explanation of symbols]

 Reference Signs List 1 engine duct 6 shaft 7 gas generator 11 small gear 12 fan 13 rotating shaft 15 external gear

Claims (2)

[Claims] 1. A rotating shaft of a fan is rotatably supported on a support frame having a gear attached to a tip end of a shaft of a gas generator mounted in an engine duct and projecting outward to the engine duct. Let me
A ring-shaped external gear is integrally attached to the outer periphery of the fan,
An ultra-high bypass ratio engine having a configuration in which the ring-shaped external gear and the gear are meshed with each other, and the fan is rotated by the gear via the ring-shaped external gear. 2. The ultra-high bypass ratio engine according to claim 1, wherein the gear ratio between the gear and the ring-shaped external gear is 1:10 or more.