JP2809362B2 - Power unit for combined helicopter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable mechanism of a thrust fan of a convertible engine used for a power unit of a compound helicopter (hereinafter referred to as a compound helicopter). The present invention can also be used for convertible engines for hovercraft.

[0002]

[Prior art]

(1) FIG. 4 shows an example of a conventional convertible engine for a compound helicopter. As shown in FIG. 4, in the rotorcraft mode, the output turbine of the engine and the thrust fan 1
The rotation of the thrust fan is stopped by rotating the planetary gear unit 4 and the planetary gear unit 7 by a multi-plate friction clutch 23, disengaging the clutch, and idling the planetary carrier (or ring gear). On the other hand, in the fixed wing machine mode, the clutch 23 is engaged, and the thrust fan 14 is rotationally driven via the planetary gear unit 7.

(2) Another example of a conventional convertible engine is shown in FIG. As shown in FIG. 5, the pitch of the thrust fan of the engine is made variable, and is set to a flat pitch (zero angle of attack) in the rotary wing mode and to a high pitch (large angle of attack) in the fixed wing mode.

[0004]

[Problems to be solved by the invention]

(1) In a compound helicopter, it is necessary to continuously and smoothly change the thrust of the thrust fan when shifting from the rotary wing mode to the fixed wing mode or vice versa. However, in the conventional system using a clutch, a large loss horsepower due to slippage is involved in the transitional state of engagement and disengagement, so that continuous use in the transitional state has been difficult.

(2) Further, in the conventional variable pitch thrust fan system, a space between blades is required to enable a change from a flat pitch to a high pitch angle, so that only a small number of blades can be arranged. Therefore, a fan with high thrust efficiency cannot be obtained. In addition, there has been a problem that the variable pitch mechanism is complicated and the weight, cost and reliability are poor. The present invention aims to provide a power plant that solves these problems.

[0006]

SUMMARY OF THE INVENTION A power unit for a combined helicopter according to the present invention is a convertible engine capable of extracting output from the same engine in each of a fixed wing aircraft mode and a rotary wing aircraft mode. A thrust fan 14 forming a part of the engine is driven by the output turbine 2 via the planetary gear device 7, and the power of the output turbine of the engine drives the rotor 6 via the extension shaft 4 and the transmission 5,

The planetary gear unit 7 includes a ring gear 8, a planet carrier 9, and a sun gear 10, the sun gear 10 is connected to the output turbine 2, the ring gear 8 (or the planet carrier 9) is connected to the thrust fan 14, and the planet carrier 9 (or ring gear 8) are each rotationally coupled to the adjacent hydraulic pump / motor 11,

The extension shaft 4 is rotatably connected to a hydraulic pump / motor 15 provided in a drive system of the transmission 5, and at least one of the two hydraulic pumps / motors 11 and 15 is of a variable displacement type and The suction side and the discharge side of the pumps / motors 11 and 15 are connected to each other by a hydraulic pipe 19, and the operating shaft can circulate between the hydraulic pumps / motors 11 and 15.

[0009]

The sun gear 10 and the ring gear 8 of the planetary gear device 7
And a differential type reduction gear obtained by coupling the planetary carrier 9 to the input shaft, the output shaft and the hydraulic pump / motor 11, respectively, is used for the thrust fan drive of the engine. Then, the variable displacement hydraulic pump / motor 15 is connected to the transmission device for driving the rotating blades, and the suction side and the discharge side of the hydraulic pump / motor 11 are connected to each other via a pipe 19 to form the variable displacement hydraulic pump 15. The rotation speed of the thrust fan 14 is changed by controlling the flow rate. The thrust fan 14 is stopped in the rotary wing aircraft mode, set to a high speed in the fixed wing aircraft mode, and can be set to a middle speed in the intermediate mode in a stepless manner.

[0010]

1 to 3 show an embodiment of the present invention.

FIG. 1 shows a power unit according to an embodiment of the present invention, FIG. 2 shows an enlarged view of a thrust fan unit of the power unit of FIG. 1, and FIG. 3 shows a hydraulic pump / motor of the power unit of FIG. The characteristic diagram is shown.

The compound helicopter equipped with the power unit of this embodiment is equipped with two engines on the left and right. One variable displacement hydraulic pump / motor 15 provided in the transmission is provided with a hydraulic pump / motor 15 for both engines. The thrust of both engines can be changed evenly by operating one swash plate angle control actuator which is connected to the motor 11 by piping.

In FIG. 1, an output turbine 2 of an engine 1
Is transmitted from the engine to the transmission 5 by the extension shaft 4 by the bevel gear 3 to drive the variable displacement hydraulic pump 15 and the rotary blade 6. On the other hand, the rotational force of the output turbine 2 is reduced by the planetary gear device 7 provided inside the engine and drives the thrust fan 14. The planet carrier 9 of the planetary gear set is rotationally connected to a hydraulic pump 11. here,
The inclination of the swash plate 17 of the hydraulic pump 15 is adjusted by the actuator 18.
, The discharge amount becomes zero, and the hydraulic pump 11
Stops, the planet carrier 9 also stops, and the planetary gear unit functions as a normal speed reducer.

On the other hand, when the inclination of the swash plate 17 is adjusted, the hydraulic oil circulates through the hydraulic pipe 19 in accordance with the inclination angle, and the rotation speed of the hydraulic pump 11 and the planet carrier 9 can be controlled. As a result, the rotation speed of the ring gear 8, that is, the rotation speed of the thrust fan can be arbitrarily adjusted between the stopped state and the maximum speed. The relationship between the flow rate of the hydraulic oil circulating through the hydraulic pump / motor, the transmission horsepower, and the rotation speed of the thrust fan is as shown in FIG. ) And the cruise state (B) can minimize the horsepower loss due to the hydraulic pump / motor in the frequently used state.

The required transmission horsepower of the hydraulic pump / motor is generally proportional to the square of the rotation speed, and therefore may be about one-fourth of the cruise thrust fan drive horsepower, and a relatively compact design as shown in FIG. Becomes possible.

[0016]

Since the present invention is configured as described above, it has the following effects. (1) A compound helicopter capable of continuously and smoothly switching from the rotary wing aircraft mode to the fixed wing aircraft mode can be realized.

(2) In the conventional convertible engine of the clutch type, a large loss of horsepower is generated when the clutch is switched, so that a large hydraulic oil cooler is required. Since high transmission efficiency (about 85%) is obtained, the size of the cooler can be reduced.

(3) In the conventional variable pitch thrust fan type convertible engine, it was difficult to design a highly efficient fan due to the restriction of the variable pitch mechanism. However, in the present invention, there is no such restriction. A highly efficient fan can be designed.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is an enlarged view of a thrust fan unit of FIG.

FIG. 3 is a characteristic diagram of the hydraulic pump / motor of FIG.

FIG. 4 is a sectional view of a conventional clutch convertible engine.

FIG. 5 is a sectional view of a conventional variable thrust fan type convertible engine.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Power turbine, 3 ... Bevel gear, 4 ... Extension shaft, 5 ... Transmission, 6 ... Rotor blade, 7 ... Planetary gear device, 8 ... Ring gear, 9 ... Planet carrier, 10 ...
Sun gear, 11 hydraulic pump / motor, 12 plunger, 13 swash plate, 14 thrust fan, 15 variable displacement hydraulic pump / motor, 16 plunger, 17 swash plate,
18 Actuator, 19 Hydraulic piping, 20 Gas generator, 21 Body, 22 Engine nacelle, 23
... multi-plate friction clutch, 24 ... hydraulic piston, 25 ... variable pitch actuator, 26 ... variable pitch linkage.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F02C 7/36 B64C 27/14 B64C 27/26 B64D 35/00

Claims (1)

(57) [Claims] 1. A convertible engine capable of extracting power from the same engine according to each of a fixed-wing aircraft mode and a rotary-wing aircraft mode, wherein a thrust fan (14) forming a part of the engine is a planetary gear unit. (7) driven by the output turbine (2), and the power of the output turbine of the engine drives the rotor (6) via the extension shaft (4) and the transmission (5), The device (7) comprises a ring gear (8), a planet carrier (9) and a sun gear (10), the sun gear (10) being connected to the power turbine (2) and the ring gear (8).
(Or planet carrier (9)) to thrust fan (14),
The planet carrier (9) (or ring gear (8)) is rotatably coupled to an adjacent hydraulic pump / motor (11), and the extension shaft (4) is connected to a hydraulic pump / motor provided in a drive system of the transmission (5). A motor (15), and at least one of the two hydraulic pumps / motors (11, 15) is of a variable displacement type;
The suction side and the discharge side of (1, 15) are respectively connected by hydraulic piping (19), and the operating shaft is hydraulic pump / motor (11, 1).
5) A power unit for a combined helicopter, wherein the power unit can circulate between 5).