JPS63212200A - Variable pitch propeller device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a variable pitch propeller device.

[Conventional technology]

As shown in FIG. 1, the forward speed Vo generated when the propeller rotates is the same in each cross section of A, At, and A3 (see FIG. 3). In FIG. 3, 2 indicates the angle of attack, β indicates the pitch angle, θ indicates the air inflow angle, and Ct, Cz, and Cs each indicate the rotational circumferential speed. This rotational peripheral speed C,,C,.

The value of C1 decreases as it approaches the center of rotation. For this reason, in order to make the forward speed vO of each part of the propeller uniform, the air inflow angle θ is set smaller as the distance from the central axis increases, and as a result, a propeller with a predetermined twist can be obtained. .

By the way, when the forward speed Vo or rotational speed of the propeller changes, the ideal pitch angle β is as shown in FIG. 4. Here, At, Az, and Ai are each s+ = 0.9 (m) from the propeller center.

St = 0.6 (ml, Ss = 0.3 m
(Let the distance be nil. Also, let ■ be the speed corresponding to the forward speed of the propeller. Then, calculate the circumferential speeds C1, C2, CS of A + , A z and A, and calculate the pitch angle β. The results shown in the diagram in Figure 2 can be obtained.

In this case, looking at the difference in pitch angle βΦ, that is, the degree of twist, in A + , A z , and A 3, in Fig. 2, in ■, rAz A,'' is 8.5°, and in ■, rAg
-At J Ka11.6"%■, "A3-Al" is 13".As is clear from this result,
When the rotational circumferential speed C, , C, , C3 or the forward speed VO changes, the torsion of the entire propeller must be changed in order to maintain the ideal pitch angle.

On the other hand, the variable pinch propeller is equipped with a plurality of blades 21 (two in the conventional example shown in FIG. 5) each having a shoulder 20 at the root as shown in FIG.
It is built into the propeller hub along with bearings, etc. A spar member 22 having relatively high rigidity is provided at the center of the blade 21. The spar member 22 and the blade 21 are integrated at their tip ends. On the other hand, since the shoulder 20 is fixed with a bearing or the like, the torsion of the blade 21 relative to the spar 22 is prevented by using a rond or the like (not shown) on the driven pin 2 of the shoulder 20.
3 to the pole (can be easily set, and this allows the pitch angle of the propeller to be changed arbitrarily from the outside.

[Problem that the invention seeks to solve]

However, the conventional variable pitch propeller is
Since all of them are for constant speed rotation, if you set the pinch angle according to the desired rotation speed before starting, even if the propeller rotation speed changes slightly during operation, the pinch angle will deviate from the optimum position. This causes the propeller to become inefficient, resulting in a loss of rotational energy and, in some cases, increased vibration and noise.

[Purpose of the invention]

The present invention aims to improve the disadvantages of the conventional example and to provide a variable pitch propeller that can always set a pitch angle close to the ideal state by following changes in the rotational speed. That purpose.

[Means for solving problems]

Therefore, the present invention includes a blade portion and a spar member that is inserted into the central portion of the blade portion in a penetrating state, and applies a predetermined amount of twist to the spar member from the propeller hub portion to the blade portion. In the variable pitch propeller device configured to do so, an automatic torsion adjustment mechanism is provided at the rotating end of the blade portion and rotates in a direction parallel to the rotational surface of the blade portion when the rotational speed of the blade portion increases. The purpose of the present invention is to achieve the above object.

(Embodiment of the Invention) An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In FIG. 1, reference numeral 1 indicates a blade portion of a propeller, and reference numeral 2 indicates a spar member. The blade portion 1 is made of a structure having relatively low torsional rigidity, and is configured to set an appropriate pitch angle between the blade portion 1 and the spar member 2 via a propeller hub portion (not shown).

To explain this in more detail, an annular shoulder 4 is attached to the rotation center side of the blade portion 1, and a driven pin 5 is provided on the drive side end surface of this shoulder 4. Of these, the shoulder 4 is attached to the propeller hub portion via a bearing.

A driving iron (not shown) for driving the driven pin 5 is installed on the central axis of the propeller hub, and the driving iron is connected between the blade l and the spar member 2 as described above via this driving iron. Appropriate twist is added.

In this embodiment, the spar member 2 is constituted by a rod-shaped member having a cross-shaped cross section. Therefore, the spar member 2 in this embodiment has a structure that has the advantages of relatively high bending strength and low torsional rigidity.

An automatic twist adjustment mechanism 10 is integrally equipped with the spar member 2 at the rotating end of the blade portion 1 . In this embodiment, the automatic twist adjustment mechanism 10 is composed of an iron bell-shaped member.

When the propeller rotates, this iron bell-shaped member automatically acts so that the weight portions 10A and 1OB at both ends become parallel to the rotating surface.

To explain this in more detail, in Fig. 2, each weight IOA
, the centrifugal force of the IOB spreads out from the center of rotation at an angle γ6. γ
2 direction. On the other hand, since the blade portion 1 has a predetermined twist with respect to the rotation direction, each of the weights 10Δ and 10B has a parallel rotation surface with a predetermined distance from the rotation surface Ko of the blade portion 1. Rotate on top. This parallel rotation surface K1. Kt, the aforementioned spread angle T3. The centrifugal forces Ft and Fz in the direction of T2 have a parallel component FIV+FtV and a perpendicular component F□ to the y-axis in the plane of the centrifugal force F, pg, respectively.

It is decomposed into Fix. Among these, the centrifugal force F+, the components F1 yo and F28 in the direction orthogonal to Fz are components in opposite directions, so that the weights 10A and 10B of the iron bell-shaped members are
A rotational moment is generated in the portion, and the rotational ends of the blade portion 1 and the spar member 2 are rotated in a direction toward the parallel plane Ko with respect to the rotational surface of the blade described above. In other words, due to the centrifugal torsional moment of the weights 10A and 10B, the iron bell-shaped member always tends to be parallel to the plane of rotation of the propeller, and as a result, the pitch angle of the propeller gradually decreases from the center toward the ends. The twist is formed smoothly and automatically. In this case, F IX+
F 2x is parallel to the plane of rotation Kl! As the propeller rotation speed increases,
Even during operation, the transition from the state (2) to the state (2) in FIG. 4 described above can be made extremely easily and smoothly.

Here, the iron bell-shaped member is installed perpendicularly to the spar member 2 as shown in FIG. 1, and its weight portions 10A, 1. O
B is the tube distance from the spar member 2 1=l! (TI41t) - Therefore, as the blade rotates, the weight IOA increases.

10B has the advantage that it acts immediately and smoothly, and that the degree of twisting of the blade section 1 is suitably and automatically finely adjusted in accordance with the rotational speed of the blade section 1. In addition, in this embodiment, by the action of the automatic twist adjustment mechanism 10, it is possible to give the propeller an efficient twist according to the propeller rotation speed and forward speed. A state with less resistance can be set, and the propeller rotation speed and forward speed range can be made larger than before.

Additionally, since the propeller blades only need a structure with low torsional rigidity, the weight can be reduced accordingly. Furthermore, it is possible to suppress the generation of vibration and noise of the propeller and improve impact resistance, etc., and by controlling the weight distribution of the entire propeller blade, it is possible to create not only uniform twist but also all kinds of twist. .

Other than that, the configuration required for the variable propeller device is the same as that of the conventional example.

In the above embodiments, the automatic twist adjustment mechanism IO is constructed from an iron bell-shaped member, but it may be constructed from other members as long as they function equally well.

〔Effect of the invention〕

Since the present invention is configured and functions as described above, it is possible to suitably and automatically finely adjust the degree of twist of the blade according to changes in the rotational speed of the propeller, thereby increasing the rotational force of the propeller. is effectively converted into thrust, resulting in less vibration and noise (this makes it possible to smoothly change the rotational speed without energy loss even when the propeller is in operation, which is an unprecedented advantage). A variable propeller device can be provided.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of a blade portion showing an embodiment of the present invention, Fig. 2 is an explanatory diagram of the operation of Fig. 1, and Figs. FIG. 5 is an explanatory diagram showing the relationship between the degree of twisting, etc., and FIG. 5 is an explanatory diagram showing a conventional example. 1...Blade part, 2--Spar member, 10-
-・-Automatic twist adjustment mechanism. Patent applicant: Suzuki Automobile Industry Co., Ltd. Figure 3

Claims (2)

[Claims] (1) Comprising a blade portion and a spar member inserted into the central portion of the blade portion, and configured to apply a predetermined amount of twist to the spar member from the propeller hub portion to the blade portion. In the variable pitch propeller device according to the present invention, an automatic twist adjustment mechanism is provided at the rotating end of the blade portion to rotate in a direction parallel to the rotating surface of the blade portion when the rotational speed of the blade portion increases. A variable pitch propeller device featuring: (2) Comprising a blade portion and a spar member inserted into the central portion of the blade portion, and configured to apply a predetermined amount of twist to the spar member from the propeller hub portion to the blade portion. In the variable pitch propeller device, an automatic torsion adjustment mechanism is provided at the rotating end of the blade portion to rotate in a direction parallel to the rotating surface of the blade portion when the rotational speed of the blade portion increases, and A variable pitch propeller, characterized in that the spar is formed of a cross-shaped member.