JP2870078B2 - Aircraft reducer - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to an aircraft speed reducer, and more particularly to an input shaft integrally connected to an engine crankshaft and a variable pitch propeller integrally. The present invention relates to an aircraft speed reducer including an output shaft to be connected, and a speed reduction mechanism provided between the two shafts to reduce the rotation of the input shaft and transmit the rotation to the output shaft.

[Conventional technology]

This type of speed reducer is conventionally used in Porsche PFM3200 type aircraft engines and speed reducers.A booster pump that discharges high-pressure oil and a governor that controls hydraulic oil supplied from this to a variable pitch propeller The booster pump is driven by the engine via a dedicated speed reducer provided between the engine and the hydraulic control device, and the output of the reducer is output from the hydraulic control device. Hydraulic oil (part of the lubricating oil in the engine / reducer) is supplied to the hydraulic oil supply passage provided in the shaft through the first pipe, and the operation is discharged from a lubricating oil supply pump provided in the engine. A part of the oil is guided to the lubricated portion of the speed reducer through the second pipe.

[Problems to be solved by the invention]

In the conventional reduction gear described above, a pipe for guiding hydraulic oil to the hydraulic oil supply passage of the output shaft and a pipe for guiding hydraulic oil to a lubricated portion of the reduction gear are required, and these pipes are required. In addition to the inevitable increase in cost and weight, it is necessary to ensure reliability against oil leakage in each pipe.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has a pipe for guiding hydraulic oil to a hydraulic oil supply passage provided on an output shaft of the speed reducer, and a hydraulic oil in a lubricated portion of the speed reducer. It is an object of the present invention to provide an aircraft speed reducer that can reduce costs and weight and improve reliability against oil leakage and the like by using a common pipe for guiding oil.

[Means for solving the problem]

In order to achieve the above object, in the present invention,
An input shaft integrally connected to an engine crankshaft;
For an aircraft, comprising: an output shaft rotatably supported by a casing and integrally connected to a variable pitch propeller; and a speed reduction mechanism provided between the two shafts to reduce the rotation of the input shaft and transmit the rotation to the output shaft. In the speed reducer, a hydraulic control device for controlling hydraulic oil supplied to the variable pitch propeller is assembled to the casing, and a supply passage of hydraulic oil from the hydraulic control device to the variable pitch propeller is formed in the casing. In addition, an introduction passage that guides hydraulic oil guided from the engine via a pipe to the hydraulic control device is formed in the casing, and a passage that guides the hydraulic oil from the introduction passage to a portion to be lubricated of the speed reducer is provided in the casing. Formed.

[Operation and Effect of the Invention] In the aircraft speed reducer according to the present invention, the hydraulic oil controlled by the hydraulic control device can be varied only by providing piping for guiding the hydraulic oil from the engine to the introduction passage formed in the casing. The pitch propeller can be guided without using piping, and a part of the hydraulic oil can be guided to the lubricated portion of the speed reducer without using piping through a passage formed in the casing from an introduction passage for guiding hydraulic oil to the hydraulic control device. Can be guided and the cost and
It is possible to reduce both the weight and the number of locations where oil leakage occurs, thereby improving the reliability against oil leakage and the like.

Further, a part of the hydraulic oil guided to the introduction passage formed in the casing through a pipe for guiding the hydraulic oil from the engine can be guided to a lubricated portion of the speed reducer through a passage formed in the casing. Even when a pump that discharges hydraulic oil toward the lubricated portion of the speed reducer is provided on the engine side, the hydraulic oil always flows continuously in the pipe, and the oil temperature and viscosity in the pipe are reduced. The change is small, and the control accuracy of the hydraulic oil supplied to the variable pitch propeller is improved.

〔Example〕

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

FIG. 1 shows an aircraft speed reducer (for a single-engine airplane) according to the present invention, which is composed of a casing A and an input shaft.
The casing A is composed of a front case 13 and a rear case 14. The output shaft 12 includes an output shaft 12, a reduction gear train (reduction mechanism) B, and the like.

The input shaft 11 is fitted at a rear end (right end in the drawing) with a coupling 16 mounted on a crankshaft 15 of the engine so as to be slidable in the axial direction and integrally rotatable, and a front end (left end in the drawing). And coaxially fit into the hollow input gear 17 and spline fit so that they can rotate together and snap ring
The axial positioning is performed by 18. Note that a seal member 19 is mounted between the outer periphery of the center of the input shaft 11 and the rear case 14.

The input gear 17 is rotatably supported by both cases 13 and 14 via a pair of radial bearings 21 and 22 and one thrust bearing 23, and is configured to be integrally rotated by the input shaft 11. As shown in FIG. 2, it is always meshed with the intermediate gear 24. The inner races of the front bearings 21 and 23 are fastened by fasteners 25 screwed to the shaft of the input gear 17.
, The outer ring of the thrust bearing 23 is integrally fixed to the front case 13 by a retainer 27 fixed to the front case 13 using a fastener 26.

The intermediate gear 24, as shown in FIG.
4 is rotatably supported via a pair of front and rear radial bearings 31 and 32, and as shown in FIG.
An output gear 33 (see FIG. 1) which is spline-fitted thereon and rotates integrally with the output shaft 12 is always meshed, and connects the input gear 17 and the output gear 33 so as to transmit power.

On the other hand, the output shaft 12 is formed in a hollow shape as shown in FIG. 1, and is rotatable between the two cases 13 and 14 via a pair of radial bearings 34 and 35 and one thrust bearing 36. And an annular flange at the front end
37 is provided with a variable pitch propeller C schematically shown in FIG. The inner races of the front bearings 34 and 36 are integrally fixed to the output shaft 12 together with the output gear 33 by fasteners 38 screwed to the output shaft 12, and the outer race of the thrust bearing 36 uses fasteners 39. It is integrally fixed to the front case 13 by a retainer 41 fixed to the front case 13. A seal member 42 is attached between the front end neck of the output shaft 12 and the front case 13.

With the above configuration, the rotation of the engine crankshaft 15 is transmitted to the output shaft 12 via the reduction gear train B including the input shaft 11 and the three gears 17, 24, 33, and the rotation of the variable The pitch propeller C is rotated at a speed reduced by a predetermined reduction ratio with respect to the speed of the engine crankshaft 15.

The variable pitch propeller C shown in FIG. 4 includes a hydraulic E cylinder 45 having a piston 43 and a return spring 44 that can move only in the axial direction, and a piston of the hydraulic cylinder 45.
A pin 46 which moves in the axial direction integrally with 43, and a housing 48 which has a cam hole 47 into which the pin 46 fits and rotates integrally with the output shaft 12 so as to be rotatable but not move in the axial direction. A hub 49 attached thereto, a gear 51 integrally formed at one end of the hub 49, and a blade 52 integrally rotatably and axially immovably mounted on the housing 48 are formed integrally with one end of a blade 52. An internal hole (operating oil supply) formed at the axis of the output shaft 12 from the pitch control hydraulic supply circuit D2 of the hydraulic control circuit D shown in FIG. When the piston 43 is moved rightward in FIG. 4 by hydraulic oil applied to the hydraulic cylinder 45 through the passageway 54, the blade 52 rotates in the direction of the arrow shown in FIG. 4 and the pitch (propeller pitch) of the blade 52 becomes high. It has been changed.

The hydraulic control circuit D shown in FIG. 5 includes a lubricating oil supply circuit D1 and a pitch control hydraulic supply circuit D2.
Is equipped with an engine oil pan 55, a strainer 56, an oil pump (lubricating oil supply pump) 57, a relief valve 58, a filter 59 with a check valve, a heat exchanger 61 with a check valve, a throttle 62, and the like. The lubricating oil supplied to the lubricated portion E of the engine is lubricated and then lubricated.
It is configured to reflux.

Further, the pitch control hydraulic supply circuit D2 includes a booster pump F that suctions a part of the hydraulic oil that has passed through the heat exchanger 61 and pressurizes and discharges the same, and a relief valve 63 that regulates the maximum discharge pressure of the booster pump F; An electromagnetic flow control valve 64, a throttle 65 and the like are provided, and the operation of the electromagnetic flow control valve 64 is controlled by the electronic control device G, whereby the flow supplied to the hydraulic silling 45 of the variable pitch propeller C is controlled. It is configured as follows.

The electromagnetic flow control valve 64 is a spring center type 3 mounted on the rear case 14 of the reduction gear together with the relief valve 63.
A port solenoid valve (see FIG. 1), wherein the electronic control unit G
The amount of supply and the amount of discharge to the hydraulic cylinder 45 can be controlled in accordance with the current value to each of the solenoids a and b, and the non-control state (for example, the electronic control unit G, the short-circuit or disconnection of the solenoids a and b, etc.) At the time of failure), the port 64a connected to the hydraulic cylinder 45 is held at the illustrated neutral position, and the port 64a connected to the discharge port of the booster pump F and the port 64c connected to the oil reservoir 66 of the reduction gear are cut off. It is configured to be. The throttle 65 is a small hole (see FIG. 1) provided at the front end of the output shaft 12, and a part (a small amount) of the hydraulic oil supplied to the hydraulic cylinder 45 is always stored in the oil sump 66 of the speed reducer. A function to constantly supply hydraulic oil to both bearings 34 and 36 of the output shaft 12 as lubricating oil, and an electromagnetic flow control valve
64 uncontrolled states (eg, electronic control unit G, solenoid a,
In the event of a failure such as a short circuit or disconnection in b), the hydraulic oil in the hydraulic cylinder 45 is released to make the pitch of the blade 52 low (the fail-safe side of a generally known single-engine airplane).

In this embodiment, as shown in FIGS. 1 and 6, a booster pump F for discharging high-pressure oil used by the variable pitch propeller C is provided at the rear end of the output shaft 12. Have been.

The booster pump F is a gear pump having a rear housing 14 and a cover 67 fixed to the rear case 14 as a pump housing.
The drive shaft 68 is hollow and coaxially fitted to the output shaft 12 via a seal ring 69 and engages with a projection provided on the output shaft 12 at a notch provided at the tip to integrally form the output shaft 12. Rotate. As shown in FIGS. 5 and 6, the discharge passage 70 of the booster pump F is connected to the relief valve 63 and the port 64b of the electromagnetic flow control valve 64, and the return passage 71 from the relief valve 63 is located rearward. The booster pump F is provided in the case 14 and connected to the suction side of the booster pump F.

On the other hand, the port 64a of the electromagnetic flow control valve 64 is connected to a through hole 72 provided in the rear case 14 and the cover 67, as shown in FIGS. The hydraulic cylinder 45 is configured to be supplied to the hydraulic cylinder 45 through a through hole 73 provided in the support shaft 68 and the inner hole 54 of the output shaft 12, and a port 64 c of the electromagnetic flow control valve 64 is provided in the rear case 14. 74
(See FIG. 1), and the output shaft
Reducer oil sump 66 after lubricating through 12 bearings 35
It is configured to return to the oil pan 55 of the engine through a through hole 75 (see FIG. 3) provided in the rear case 14.

In this embodiment, FIGS. 1, 5, and 6
As shown in the figure, a small hole (oil jet) 76 is provided in the rear case 14 for always guiding a certain amount of hydraulic oil from the suction side of the booster pump F to the bearing 35 that supports the output shaft 12. The bearing 35 is configured to be lubricated by the operating oil supplied through the small hole 76.

In the present embodiment configured as described above, the booster pump F provided at one end of the output shaft 12 having the hydraulic oil supply passage (inner hole) 54 to the variable pitch propeller C, and the relief valve provided near the booster pump F By simply providing a pipe 77 (see FIG. 5) for guiding hydraulic oil from the engine side to a hydraulic control device such as 63, an electromagnetic flow control valve 64, etc., the hydraulic oil controlled by the hydraulic control device is connected to the output shaft 12. It is possible to guide the hydraulic oil supply passage 54 of the output shaft 12 to the hydraulic oil supply passage 54 without using a pipe through oil passages 70 and 72 formed in a casing or the like that supports the shaft, and to supply the hydraulic oil supplied from the engine side to the hydraulic control device. A small hole partly provided in the rear case 14 on the suction side of the booster pump F
It is possible to guide the output shaft 12 to the bearing 35 that supports the output shaft 12 without using a pipe through the pipe 76, and to share the pipe (in other words, to connect the hydraulic oil supply pipe to the hydraulic control device and the lubricating oil to the bearing 35 with the pipe 77). The cost and weight can be reduced both by using the supply pipe as well) and by using less, and the reliability of oil leakage and the like can be improved by reducing the number of locations where oil leakage occurs.

Further, in the present embodiment configured as described above, since the booster pump F is directly driven by the output shaft 12 through which the rotation of the engine crankshaft 15 is transmitted in a reduced speed, there is no need to use a dedicated reduction gear. Booster pump F
Can be driven at a low speed, the booster pump F can be operated with high efficiency, and the cost and weight can be reduced by eliminating a dedicated speed reducer, and the number of failure sites can be reduced. Reliability can be improved.

Further, in this embodiment configured as described above, the hydraulic control device such as the relief valve 63 and the electromagnetic flow control valve 64 is provided at one end of the output shaft 12 together with the booster pump F. The distance from the hydraulic control device to the variable pitch propeller C, which is close to the passage 54, can be reduced as compared with the related art, and the operation responsiveness of the variable pitch propeller C can be improved. In addition, the excess hydraulic oil generated by the hydraulic control device is led to the bearing 35 that supports the output shaft 12 of the speed reducer through the through hole 74 provided in the case 14, and returned to the oil reservoir 66 through the bearing 35. Thus, the lubrication of the speed reducer can be improved without increasing the cost.

In the above embodiment, the hydraulic oil is guided from the suction side of the booster pump F to the bearing 35 through the small hole 76 provided in the rear case 14. However, in the embodiment of the present invention, the hydraulic oil is guided to the discharge side of the booster pump F (for example, , The passageway 70) through a small hole provided in the rear case 14 to guide the hydraulic oil to the bearing 35 that supports the output shaft 12 or the bearing 32 that supports the intermediate gear 24. When such a configuration is adopted, the booster pump may be provided on the engine side.

When the booster pump is provided on the engine side (in this case, the relief valve 63 is also usually provided on the engine side), the introduction passage (the hydraulic control device) formed in the casing through a pipe for guiding the hydraulic oil from the engine is also provided. A part of the hydraulic oil guided to the hydraulic fluid) can be guided to a lubricated portion of the speed reducer through a passage formed in the casing, so that the hydraulic oil always flows continuously in the pipe. Therefore, changes in oil temperature and viscosity in the pipe are reduced, and the control accuracy of the hydraulic oil supplied to the variable pitch propeller is improved.

In the above embodiment, the operation of the variable pitch propeller C is controlled by using the hydraulic control circuit D. However, the operation of the variable pitch propeller C is controlled by a conventional governor (hydraulic control governor). It is possible to implement the present invention in this way, or to change the configuration of the variable pitch propeller C as appropriate to implement the present invention.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of an aircraft speed reducer according to the present invention, FIG. 2 is a sectional view showing the relationship between an input gear and an intermediate gear of the speed reducer, and FIG. FIG. 4 is a schematic configuration diagram of a variable pitch propeller mounted on an output shaft, and FIG. 5 is a hydraulic control including a pitch control hydraulic supply circuit for supplying hydraulic oil to the variable pitch propeller. FIG. 6 is a vertical sectional rear view of the booster pump. Explanation of reference numerals 11 ... input shaft, 12 ... output shaft, 14 ... rear case, 15 ...
... Crankshaft, 35 ... Bearing (part to be lubricated), 54 ...
... Hydraulic oil supply passage, 63, 64 ... Relief valve, electromagnetic flow control valve (hydraulic control device), 67 ... Cover, 76 ... Small hole (passage), 77 ... Piping, B ... Reduction gear train ( Reduction mechanism), C
...... Variable pitch propeller.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-49-124795 (JP, A) Patent 132847 (JP, C2) (58) Fields investigated (Int. Cl. ⁶ , DB name) B64C 11/38 -11/42 F16H 57/04

Claims (1)

(57) [Claims] 1. An input shaft integrally connected to a crankshaft of an engine, an output shaft supported by a casing and integrally connected to a variable pitch propeller, and the input shaft provided between these two shafts. In an aircraft speed reducer having a speed reduction mechanism for reducing the rotation of a shaft and transmitting the rotation to the output shaft, a hydraulic control device for controlling hydraulic oil supplied to the variable pitch propeller is assembled to the casing, and the hydraulic pressure A passage for supplying hydraulic oil from the control device to the variable pitch propeller is formed in the casing, and an introduction passage for guiding hydraulic oil guided from the engine via a pipe to the hydraulic control device is formed in the casing. A reduction gear for an aircraft, wherein a passage for guiding hydraulic oil from an introduction passage to a lubricated portion of the reduction gear is formed in the casing.