Variable lift hydrofoil

Abstract

To provide a hydrofoil capable of controlling the direction of travel of a vehicle by increasing or decreasing the area of ​​the wing surface. [Solution] The hydrofoil of the present invention is a hydrofoil that controls the motion of a navigation body and is capable of changing the area of ​​the wing surface of the hydrofoil main body. The hydrofoil has a structure in which a first plate-like body, a second plate-like body, and a third plate-like body are stacked in three layers. The peripheral portions of the first plate-like body and the second plate-like body are connected to form a box-like body, and the third plate-like body is housed inside the box-like body so as to be movable in a direction perpendicular to the length direction of the slit. The rotation shaft is connected to the box-like body. And, two resistance plates are provided on the front upper side of the third plate-like body so as to face upward.

Description

[Technical field]

[0001] The present invention relates to a hydrofoil with variable lift. [Background technology]

[0002] Conventionally, the progress and depth of a moving body (hereinafter referred to as a "vehicle") traveling on or underwater has been controlled by changing the angle of the hydrofoil (including the rudder). For example, Patent Document 1 discloses an automatic depth-keeping device for a submarine that controls the depth by controlling the diving rudder and side rudder to apply a moment to the hull, and detects the difference between the rudder control signal applied to the diving rudder and the rudder angle limit value of the diving rudder, and when the rudder control signal exceeds the rudder angle limit value, holds the diving rudder at the rudder angle limit value while correcting the diving rudder angle range that exceeds the rudder angle limit value with the side rudder to maintain the set depth.

[0003] The automatic depth control device described in Patent Document 1 provides improved depth control function, especially at low speeds. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Unexamined Patent Publication No. 61-110695 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the automatic depth keeping device described in Patent Document 1 is similar to the directional control of conventional vessels in that it controls the direction of the hull by changing the rudder angle, and has the problem that it takes time for the rudder direction to change and the direction of the hull cannot be controlled in a short period of time.

[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a hydrofoil capable of controlling the direction of travel of a vehicle by increasing or decreasing the area of ​​its wing surface. [Means for solving the problem]

[0007] A hydrofoil according to a first embodiment of the present invention is a hydrofoil that controls the motion of a vessel, and is capable of changing the wing surface area of ​​the hydrofoil main body.

[0008] In general, the lift generated by a hydrofoil is expressed by the following formula: F=CL 1 / 2ρU U S however F: Lift CL: Lift coefficient is determined by the shape of the hydrofoil and is a function of the hydrofoil's angle of attack. ρ: density of water U: Water inflow velocity S: Wing area The hydrofoil according to the first embodiment of the present invention is intended to control the lift force F by changing S in the above equation and the area of ​​the wing surface. Possible mechanisms for changing the area of ​​the wing surface include a mechanism for opening and closing slits in the hydrofoil, and a mechanism for arranging multiple rotatable fins in parallel with the axis of rotation of the hydrofoil.

[0009] The hydrofoil of the second form of the present invention is the hydrofoil of the first form, wherein the hydrofoil body is composed of a plurality of plate-like bodies, slits are formed in all of the plate-like bodies that penetrate all of the plate-like bodies, and the penetration area of ​​the slits changes depending on the change in the relative positions of the plurality of plate-like bodies. By changing the relative positions of the multiple plate-like bodies, the total area penetrating all the plate-like bodies changes, making it possible to change the lift even while keeping the angle of attack of the hydrofoil constant.

[0010] A hydrofoil according to a third aspect of the present invention is the hydrofoil according to the second aspect, The hydrofoil body has a rotation axis and a longitudinal direction A plurality of parallel slits are formed parallel to the rotation axis, and the plurality of plate-like bodies are hydrofoils whose relative positions change in a direction perpendicular to the length direction of the slits. Since the axis of rotation of an underwater foil is usually arranged in a direction perpendicular to the direction of movement of the vehicle, the underwater foil of the third form of the present invention can be equipped with a mechanism for converting the resistance caused by the water flow generated by the movement of the vehicle into force, thereby making it possible to open and close the slit by utilizing the water flow.

[0011] A hydrofoil according to a fourth aspect of the present invention is the hydrofoil according to the third aspect, in which the hydrofoil body is constituted by two layers of plate-like bodies. One of the plate-like bodies is connected to the rotation axis of the hydrofoil, and the other is a hydrofoil that is movable in a direction perpendicular to the length of the slit.

[0012] A hydrofoil according to a fifth aspect of the present invention is the hydrofoil according to the third aspect, wherein the hydrofoil body has a three-layer structure of a first plate-like body, a second plate-like body, and a third plate-like body; The first plate-like body and the second plate-like body are joined at both sides perpendicular to the rotation axis to form a box-like body, The above The hydrofoil is provided with a rotation shaft, and the third plate-like body is provided within the box body so as to be slidable in a direction perpendicular to the length direction of the slit. The total area of ​​the slits passing through the hydrofoil changes when the third plate-like body moves inside the box in a direction perpendicular to the length of the slits.

[0013] The hydrofoil according to a sixth aspect of the present invention is the hydrofoil according to the fifth aspect, and has a resistance plate provided on the third plate-like body in a standing manner parallel to the rotation axis and protruding from the box body. The resistance plate, which is erected on the third plate-like body parallel to the rotation axis, protrudes from the box body, so that as the vehicle moves, it experiences water resistance in the opposite direction to the direction of travel of the vehicle. This causes the third plate-like body, which is integrated with the resistance plate, to move in the opposite direction to the direction of travel of the vehicle. If the total area of ​​the slits penetrating the hydrofoil is reduced, the lift applied to the hydrofoil increases, and if the total area of ​​the slits is increased, the lift applied to the hydrofoil decreases. In addition to the resistance plate, hydraulic or mechanical power can also be used as a means for moving the third plate-like body. Effect of the Invention

[0014] According to the hydrofoil of the present invention, the lift can be controlled without changing the angle of attack of the hydrofoil. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a perspective view showing the structure of a hydrofoil 10 (closed state). [Diagram 2] FIG. 2 is a perspective view showing the structure of the hydrofoil 10 (in an open state). [Diagram 3] FIG. 3 is a cross-sectional view taken along line AA in FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line BB in FIG. [Diagram 5] FIG. 5 is a cross-sectional view taken along line AA in FIG. [Figure 6] FIG. 6 is a cross-sectional view taken along line BB in FIG. [Figure 7] FIG. 7 is an explanatory diagram showing the movement of the automatic floating and sinking marine buoy 90. As shown in FIG. [Figure 8] FIG. 8 is an explanatory diagram showing the movement of the self-maintaining marine buoy 92. As shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] (Embodiment) [Structure of Hydrofoil 10] The structure of the slit 30 of the hydrofoil 10 in the closed state according to the embodiment of the present invention will be described below with reference to the drawings. Fig. 1 is a perspective view showing the structure of the slit 30 of the hydrofoil 10 in the closed state. Fig. 2 is a perspective view showing the structure of the slit 30 of the hydrofoil 10 in the open state. Fig. 3 is a cross-sectional view taken along line AA in Fig. 1. Fig. 4 is a cross-sectional view taken along line BB in Fig. 1. Fig. 5 is a cross-sectional view taken along line AA in Fig. 2. Fig. 6 is a cross-sectional view taken along line BB in Fig. 2.

[0017] In this specification, directions are defined as follows. The box body 50 of the hydrofoil 10 extends in the front-rear direction. The front-rear axis, left-right axis, and up-down axis are perpendicular to one another. The upward, downward, leftward, rightward, forward, and rearward directions are directions defined for the convenience of explanation. Therefore, these directions do not have to match the directions when the hydrofoil 10 is in use. Furthermore, the upward and downward directions may be interchanged, the leftward and rightward directions may be interchanged, and the forward and rearward directions may be interchanged.

[0018] In this specification, "extending in the front-rear direction" includes extending in a direction parallel to the front-rear direction and extending in a direction slightly tilted to the front-rear direction. "extending in the left-right direction" includes extending in a direction parallel to the left-right direction and extending in a direction slightly tilted to the left-right direction. "extending in the up-down direction" includes extending in a direction parallel to the up-down direction and extending in a direction slightly tilted to the up-down direction.

[0019] In this specification, for example, "a first member is connected to a second member" includes a case where the first member is directly connected to the second member and a case where the first member is connected to the second member via a third member. Also, for example, "a first member is supported by a second member" includes a case where the first member is directly supported by the second member and a case where the first member is supported by the second member via a third member.

[0020] The disclosure is merely an example, and those who are skilled in the art can easily come up with appropriate modifications that maintain the gist of the invention, and naturally, these modifications are included in the scope of the present invention. In addition, the drawings may be more schematic than the actual embodiment in order to make the explanation clearer, but they are merely an example and do not limit the interpretation of the present invention.

[0021] In each figure, the reference numerals may be omitted for the same or similar elements arranged consecutively. In addition, in this specification and each figure, the same reference numerals may be used for components that perform the same or similar functions as those described above with respect to the previous figures, and duplicate detailed descriptions may be omitted.

[0022] As shown in Figs. 1 and 2, the hydrofoil 10 is composed of a hydrofoil body 20 and a rotating shaft 60. The hydrofoil body 20 has a structure in which a first plate-like body 21, a second plate-like body 22, and a third plate-like body 23 are laminated in three layers. The peripheral parts of the first plate-like body 21 and the second plate-like body 22 are connected to form a box body 50, and the third plate-like body 23 is housed inside the box body 50 so as to be movable in a direction perpendicular to the rotating shaft 60. The rotating shaft 60 is connected to the box body 50. Two resistance plates 40 are provided on the front upper side of the third plate-like body 23 so as to face upward. It is desirable that the sliding portion between the peripheral part of the box body 50 and the third plate-like body 23 is formed of a material with low friction resistance, or a sliding resistance reducing mechanism such as a roller bearing or a ball bearing is provided.

[0023] The first plate-like body 21, the second plate-like body 22, and the third plate-like body 23 are provided with a plurality of slits 30 of the same shape, and in the state shown in Fig. 1, the slits 30 of the first plate-like body 21 and the second plate-like body 22 are blocked by the third plate-like body 23. Fig. 2 shows a state in which the third plate-like body 23 has moved forward from the state shown in Fig. 1, so that the slits 30 of the first plate-like body 21 and the second plate-like body 22 and the slits 30 of the third plate-like body are in the same position, and all of the slits 30 penetrate in the vertical direction.

[0024] The structure of the hydrofoil 10 will be described in more detail with reference to Figures 3 to 6. Figure 3 is a cross-sectional view taken along line AA in Figure 1, and Figure 4 is a cross-sectional view taken along line BB in Figure 1. A portion of the third plate-like body 23 without slits 33a-33g is located between each of the slits 31a-31g of the first plate-like body 21 and each of the slits 32a-32g of the second plate-like body, thereby blocking each of the slits 31a-31g of the first plate-like body 21 and each of the slits 32a-32g of the second plate-like body.

[0025] Fig. 5 is a cross-sectional view taken along line AA in Fig. 2, and Fig. 6 is a cross-sectional view taken along line BB in Fig. 2. In Fig. 6, the third plate-like body 23 has moved forward compared to Fig. 4. Then, the slits 31a-31g of the first plate-like body 21 and the slits 32a-32g of the second plate-like body overlap with the slits 33a-33g of the third plate-like body 23, forming slits that penetrate the hydrofoil 10 in the vertical direction. As a result, the area of ​​the wing surface of the hydrofoil 10 is reduced compared to the state in Fig. 1.

[0026] [Hydrofoil 10 movement] Next, the operation of the hydrofoil 10 will be described with reference to Figures 1 and 2. Figure 1 shows a state in which the third plate-like body 23 is located at the rear end of the box body 50. In this state, when a force due to a water current is applied to the resistance plate 40 in the forward direction, the third plate-like body 23 integrated with the resistance plate 40 moves forward and stops at the front end of the box body 50. In the state of Figure 2, when a force due to a water current is applied to the resistance plate 40 in the rearward direction, the third plate-like body 23 integrated with the resistance plate 40 moves rearward and stops at the rear end of the box body 50. In this way, the area of ​​the wing surface of the hydrofoil 10 changes depending on the direction of the force applied to the resistance plate 40.

[0027] [Effects of the hydrofoil 10] When a vehicle equipped with hydrofoil 10 moves on or underwater, in addition to controlling the direction of motion of the vehicle by changing the angle of attack of the hydrofoil, it is also possible to control the direction of motion of the vehicle by changing the area of ​​the wing surface while keeping the angle of attack of the hydrofoil constant.

[0028] (First Example) [Structure of the Automatic Floating and Sinking Ocean Buoy 90] FIG. 7 is an explanatory diagram showing the movement of an automatic floating and sinking marine buoy 90 equipped with the hydrofoil 10 of the present invention. The automatic floating and sinking marine buoy 90 is equipped with a buoyancy adjusting device that adjusts the amount of water in the buoy, and is a type that can adjust buoyancy and repeatedly float and sink. The automatic floating and sinking marine buoy 90 is equipped with two pairs of hydrofoils 10a and 10c, and 10b and 10d (not shown) of the present invention on the upper part of a cylindrical body. Note that the hydrofoils 10a to 10d have resistance plates (not shown) similar to the hydrofoils shown in FIG. 1 and FIG. 2, and the slits are closed when sinking and open when rising.

[0029] [Movement of the Automatic Floating and Sinking Ocean Buoy 90] The angle of attack of the hydrofoils 10a-10d of the automatic floating and sinking marine buoy 90 can be changed, but in this embodiment, the movement is explained by changing the area of ​​the wing surface while keeping the angle of attack constant. In Fig. 7, the automatic floating and sinking marine buoy 90 repeats automatic rising and sinking ((a)-(e)) from the sea surface 100. When sinking from (a) to (c), the slits of the hydrofoils 10a-10d are in a closed state, and the automatic floating and sinking marine buoy 90 sinks to the lower left of Fig. 7 along the sinking flow line DL1.

[0030] Next, when the hydrofoils 10a-10d ascend from (c) to (e), the slits of the hydrofoils 10a-10d are open, and the surface area of ​​the hydrofoils 10a-10d is reduced. As a result, the lift of the hydrofoils 10a-10d is less when the hydrofoils ascend than when the hydrofoils descend, so the direction of the automatic floating and sinking marine buoy 90 changes more gradually, and the hydrofoil 90 ascends along the floating line UL1 to a position different from when the hydrofoils started to sink.

[0031] (Second Example) [Structure of Automatic Position-Maintaining Marine Buoy 92] FIG. 8 is an explanatory diagram showing the movement of an automatic fixed-position marine buoy 92 equipped with the hydrofoil 10 of the present invention. The automatic fixed-position marine buoy 92 floats on the sea surface, but is equipped with the hydrofoils 10s, 10t, 10u, and 10v (not shown) of the present invention in an area under the sea surface that is not affected by waves. The hydrofoils 10s, 10t, 10u, and 10v can change the angle of attack and the area of ​​the wing surface. The automatic fixed-position marine buoy 92 moves on the sea surface by utilizing the lift generated in the hydrofoils 10s, 10t, 10u, and 10v by the up and down motion caused by the waves. The hydrofoils 10s to 10v have resistance plates (not shown) like the hydrofoils shown in FIG. 1 and FIG. 2, and the slits are closed when sinking and open when surfacing, so that the area of ​​the wing surface decreases when surfacing.

[0032] [Movement of the Automatic Position-Keeping Ocean Buoy 92] FIG. 8 shows the movement of the self-positioning marine buoy 92 at a wave crest 102, a wave trough 104, and a point 103 between the crest and the trough. The hydrofoils 10t and 10v are set to a constant angle of attack, and are structured so that the area of ​​the wing surface decreases when the buoy rises up as described above. The self-positioning marine buoy 92 moves up and down depending on the wave height, and accordingly, the hydrofoils 10s, 10t, 10u, and 10v in the water also move up and down. The self-positioning marine buoy 92 repeatedly rises up and sinks ((a) to (e)) from the wave crest 102 to the wave trough 104. And, accompanying this movement, the hydrofoils 10s, 10t, 10u, and 10v also repeatedly rise up and sink.

[0033] Since the hydrofoils 10t, 10v are set to a constant angle of attack, the automatic station-keeping marine buoy 92 sinks to the lower left in Fig. 8 when it sinks from (a) to (c). Next, when it surfaces from (c) to (e), the slits of the hydrofoils 10a to 10d are open, and the surface area of ​​the hydrofoils 10a to 10d is reduced. As a result, the lift of the hydrofoils 10a to 10d is less when it surfaces than when it sinks, so the direction of the automatic station-keeping marine buoy 92 changes more gradually, and it surfaces in a different position than when it started to sink.

[0034] The automatic fixed position marine buoy 92 has a function of controlling the angle of attack of the hydrofoils 10a-10d when the staying position is changed by the ocean current, and returning it to the fixed position by using the up and down movement of the waves. In order to move using this function, it is necessary to change the angle of attack and the lift when sinking and surfacing, but it is usually difficult to change the angle of attack instantly in accordance with the up and down movement of the waves. According to the present invention, it is possible to change the lift without changing the angle of attack by changing the area of ​​the wing surface.

[0035] (Other embodiments) The hydrofoil according to the present invention is not limited to the hydrofoil 10, and can be modified within the scope of the present invention. For example, a hydrofoil having a streamlined cross section in a direction perpendicular to the axis of rotation may be divided into upper and lower halves to allow the relative positions to be changed, forming a two-layer structure, with slits provided in each. [Explanation of symbols]

[0036] 10 Hydrofoil 10a hydrofoil 10b hydrofoil 10c hydrofoil 10d Hydrofoil 10s hydrofoil 10t hydrofoil 10u hydrofoil 10v hydrofoil 20 Hydrofoil body 21 First plate-like body 22 Second plate-like body 23 Third plate 30 Slit 31a Slit 31b Slit 31c Slit 31d Slit 31e Slit 31f Slit 31g slit 32a Slit 32b Slit 32c slit 32d slit 32e Slit 32f Slit 32g slit 33a Slit 33b Slit 33c Slit 33d slit 33e Slit 33f Slit 33g slit 40 Resistance plate 50 box body 60 Rotational Axis 90 Automatic floating and sinking marine buoy 92 Automatic Position-Maintaining Marine Buoy 100 sea level 102 Wave Peak 103 Between the peak and the trough 104 Valley of the Waves UL1 Floating flow line DL1 Sedimentation flow line

Claims

1. A hydrofoil for controlling the motion of a vehicle, comprising: An underwater foil whose main body is composed of a plurality of plate-like bodies, all of which have slits formed therein that penetrate all of the plate-like bodies, and which can change the area of ​​the wing surface of the underwater foil main body by changing the relative positions of the plurality of plate-like bodies, thereby changing the penetration area of ​​the slits.

2. An underwater foil as described in claim 1, wherein the slits, whose length is parallel to the rotation axis provided in the underwater foil body, are formed parallel to the rotation axis, and the multiple plate-like bodies change their relative position in a direction perpendicular to the length direction of the slits.

3. The hydrofoil according to claim 2, wherein the hydrofoil body is constructed from two layers of plate-like bodies.

4. The hydrofoil body has a three-layer structure including a first plate-like body, a second plate-like body, and a third plate-like body, The hydrofoil described in claim 2, wherein the first plate-like body and the second plate-like body form a box-like body joined at both sides perpendicular to the rotation axis, the rotation axis is provided in the box-like body, and the third plate-like body is provided within the box-like body so as to be slidable in a direction perpendicular to the longitudinal direction of the slit.

5. The hydrofoil according to claim 4, further comprising a resistance plate provided on the third plate body in a standing manner parallel to the rotation axis and protruding from the box body.

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