Foreign object collection device

Abstract

To recover fine foreign matter in water without sacrificing power performance of a vessel propeller.SOLUTION: A foreign matter recovery device is provided in a vessel propeller for imparting propulsion force to a hull. The foreign matter recovery device includes an anti-ventilation plate (41) spreading in the horizontal direction and a recovery unit (51) provided on the anti-ventilation plate. A channel (49) from a water inlet (47) to a drain outlet (48) is formed in the anti-ventilation plate and a filter is provided in the recovery unit capable of recovering fine grain state foreign matter from water flow in the channel.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a foreign object recovery device. [Background technology]

[0002] In recent years, pollution of oceans, lakes, rivers, etc. by garbage has become a serious environmental destruction problem. In particular, pollution by tiny plastic fragments called microplastics has attracted attention. Since tiny foreign matter such as microplastics has a large impact on aquatic organisms, active measures to collect these foreign matter are desired. In the case of an outboard motor that takes in cooling water for the power source from underwater, there is known a device in which a strainer or the like is provided in the cooling water flow path (see, for example, Patent Document 1). In the marine propulsion device of Patent Document 1, tiny foreign matter that slips through the mesh of the strainer is discharged into the water without being collected.

[0003] Also, a foreign object collection device that is retrofitted to a marine propulsion unit has been proposed (see, for example, Patent Document 2). The foreign object collection device described in Patent Document 2 is attached above an anti-ventilation plate of the marine propulsion unit. A flow path is formed in the case body of the foreign object collection device from a water intake at the front to a drain outlet at the rear, and a filter capable of capturing fine foreign objects is disposed midway along this flow path. While traveling, water flows into the flow path from the water intake, fine foreign objects in the water are removed by the filter, and the water is discharged from the drain outlet. When traveling at high speeds, the foreign object collection device is exposed above the water surface, reducing running resistance. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 61-184198 [Patent Document 2] Patent Publication No. 2021-008199 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the foreign object collection device described in Patent Document 2 is a large device targeted at medium to large ship propulsion units, and adding such a foreign object collection device to a small ship propulsion unit is not practical. Also, while the foreign object collection device reduces running resistance during high-speed driving, there is a problem in that the foreign object collection device increases running resistance during normal driving.

[0006] The present invention has been made in consideration of the above-mentioned points, and has an object to provide a foreign object recovery device that can recover small foreign objects in water without sacrificing the power performance of a marine propulsion engine. [Means for solving the problem]

[0007] The foreign object recovery device according to one aspect of the present invention is a foreign object recovery device provided in a ship propulsion device that applies a propulsive force to a hull, the foreign object recovery device comprising: an anti-ventilation plate extending in a horizontal direction; Rear of The above problem is solved by providing an anti-ventilation plate with a collection section provided in the anti-ventilation plate, a flow path from the water intake to the water discharge outlet, and a filter capable of collecting fine foreign matter from the water flow in the flow path provided in the collection section. Effect of the Invention

[0008] According to the foreign object collection device of one aspect of the present invention, the water flow in the flow passage of the anti-ventilation plate passes through a filter, thereby removing fine foreign objects such as microplastics from the water flow, and a foreign object collection measure is implemented while the ship is traveling. In addition, since a collection section is provided in the anti-ventilation plate, the running resistance is unlikely to increase during both normal and high-speed traveling, and the power performance of the ship propulsion unit is not sacrificed. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a right side view of the outboard motor of the present embodiment. [Diagram 2] FIG. 2 is a perspective view of the foreign object recovery device and its surroundings according to the present embodiment. [Diagram 3] 1 is a perspective view of a foreign object recovery device according to an embodiment of the present invention; [Figure 4] FIG. 2 is a perspective view of a recovery section of the present embodiment. [Diagram 5] 5 is a cross-sectional view of the recovery section of FIG. 4 in this embodiment taken along line AA. [Figure 6] FIG. 4 is a diagram showing the flow of water when the marine vessel of the present embodiment is traveling forward. [Figure 7] FIG. 4 is a diagram showing the flow of water when the boat of the present embodiment is traveling backward. [Figure 8] FIG. 13 is a right side view of the foreign object collecting device and its surroundings for an outboard motor according to a modified example. [Figure 9] FIG. 13 is a right side view of the vicinity of a foreign object collecting device for an outboard motor according to another modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A foreign object recovery device according to one aspect of the present invention is provided in a ship propulsion unit that provides a propulsive force to a ship body. The foreign object recovery device includes an anti-ventilation plate that extends in a horizontal direction and a recovery unit provided in the anti-ventilation plate. A flow path is formed in the anti-ventilation plate from a water intake port toward a water discharge port, and a filter capable of recovering fine foreign objects from the water flow in the flow path is provided in the recovery unit. When the water flow in the flow path of the anti-ventilation plate passes through the filter, fine foreign objects such as microplastics are removed from the water flow, and a foreign object recovery measure is implemented while the ship is traveling. In addition, since the recovery unit is provided in the anti-ventilation plate, running resistance is suppressed both during normal traveling and during high-speed traveling, and the power performance of the ship propulsion unit is not sacrificed. EXAMPLES

[0011] An outboard motor (outboard drive) to which the foreign object recovery device of this embodiment is applied will be described below with reference to the attached drawings. In this embodiment, an outboard motor will be described as an example of a marine propulsion device, but the foreign object recovery device can also be applied to other marine propulsion devices such as inboard / outboard motors (inboard engine / outboard drive). Figure 1 is a right side view of the outboard motor of this embodiment. In the following figures, the arrow FR indicates the front, the arrow RE indicates the rear, the arrow L indicates the left, and the arrow R indicates the right.

[0012] As shown in FIG. 1, the outboard motor 1 is an electric outboard motor powered by an electric motor 12. The outboard motor 1 is attached to a transom board 2 at the stern, and the driving force of the electric motor 12 is transmitted to a propeller 34 to generate thrust for the boat. A motor cover 11 is provided on the top of the outboard motor 1. The electric motor 12, an inverter (not shown), a pump (not shown), etc. are housed inside the motor cover 11. A handle 13 for steering the boat is provided in front of the motor cover 11. A base end of the handle 13 is connected to an attachment 15 via a handle shaft 14, and the attachment 15 is connected to the upper end of a shaft housing 21.

[0013] The shaft housing 21 extends downward from the motor cover 11. A drive shaft 22 connected to the electric motor 12 is housed vertically inside the shaft housing 21. A swivel bracket 23 is provided around the periphery of the upper half of the shaft housing 21, and the shaft housing 21 is rotatably supported by the swivel bracket 23. A pair of clamp brackets 25, one on the left and one on the right, are provided on the swivel bracket 23 via a tilt shaft 24. The transom board 2 is clamped by each clamp bracket 25, and the swivel bracket 23 is moved in the tilt direction around the tilt shaft 24.

[0014] A heat sink 26 that is wide in the front-to-rear direction is formed at the bottom of the shaft housing 21. A cooling water passage is formed in the motor cover 11 and the shaft housing 21 to circulate cooling water between the heat sink 26 and the pump in the motor cover 11. Cooling water heated in the motor cover 11 is cooled by the heat sink 26 through the cooling water passage. A gear case 31 is provided below the heat sink 26. The drive shaft 22 that protrudes downward from the shaft housing 21 is housed inside the gear case 31. A skeg 32 that functions as a straightening plate is formed at the bottom of the gear case 31.

[0015] A propeller shaft 33 connected to the drive shaft 22 is housed sideways inside the gear case 31. The propeller shaft 33 protrudes rearward from the gear case 31, and a propeller 34 is attached to the protruding portion of the propeller shaft 33. The drive shaft 22 and the propeller shaft 33 are connected via a bevel gear, so that the rotation of the drive shaft 22 is converted into the rotation of the propeller shaft 33, and the power of the electric motor 12 is converted into the propulsion force of the boat. An anti-ventilation plate 41 is provided near the boundary between the gear case 31 and the heat sink 26 to suppress the inflow of air from the water surface into the propeller 34.

[0016] Incidentally, as an environmental measure, it is desirable to collect fine foreign matter such as microplastics from the sea, lakes, rivers, etc. Although it is possible to provide a foreign matter collection device on the anti-ventilation plate 41 as a retrofit, the user must perform the work required to retrofit the anti-ventilation plate 41. In addition, the addition of a collection device may increase the running resistance, which may result in a decrease in the power performance of the outboard motor 1. Therefore, the outboard motor 1 of this embodiment is provided with a foreign matter collection device 40 that has a foreign matter collection flow path formed inside the anti-ventilation plate 41.

[0017] The detailed configuration of the foreign object recovery device will be described below with reference to Fig. 2 to Fig. 5. Fig. 2 is a perspective view of the foreign object recovery device and its periphery in this embodiment. Fig. 3 is a perspective view of the foreign object recovery device in this embodiment. Fig. 4 is a perspective view of the recovery section in this embodiment. Fig. 5 is a cross-sectional view of the recovery section in Fig. 4 of this embodiment taken along line AA.

[0018] As shown in FIG. 2, a foreign object recovery device 40 is attached to the heat sink 26. The outer shell of the foreign object recovery device 40 is formed by an anti-ventilation plate 41. The anti-ventilation plate 41 spreads out horizontally from the rear side of the outer circumferential surface of the heat sink 26 so as to cover the propeller 34 from above. The tilt angle of the outboard motor 1 (see FIG. 1) is adjusted so that the anti-ventilation plate 41 is approximately parallel to the water surface when the boat is planing (running at high speed). The anti-ventilation plate 41 is formed in a generally elliptical shape when viewed from above, with a portion of the front side cut out along the outer circumferential surface of the heat sink 26.

[0019] The anti-ventilation plate 41 is formed into a flat plate shape with a predetermined thickness (for example, 25 mm) by a plate case 42 with an open bottom and a plate cover 43 covering the bottom of the plate case 42. By forming the anti-ventilation plate 41 into a flat plate shape, an increase in running resistance caused by the anti-ventilation plate 41 is suppressed. An attachment portion 44 protrudes from the top surface of the plate cover 43, and the attachment portion 44 is attached to the heat sink 26 by a pair of bolts 45. In this manner, the anti-ventilation plate 41 is detachably attached to the heat sink 26.

[0020] A cartridge-type collection unit 51 is attached to the rear of the anti-ventilation plate 41. The collection unit 51 is inserted into the anti-ventilation plate 41 from the rear, and the collection unit 51 is fixed to the plate case 42 by a thumbscrew 46. An arch-shaped knob 53 is provided on the rear surface of the collection unit 51, and the collection unit 51 is removed from the anti-ventilation plate 41 by removing the thumbscrew 46 from the plate cover 43 and pulling out the knob 53. Because the collection unit 51 is of the cartridge type, the replacement work of a filter 62 (see FIG. 4), which will be described later and is provided in the collection unit 51, is simplified.

[0021] As shown in Figures 3(A) and 3(B), the plate cover 43 is screwed to the plate case 42 at multiple locations. A pair of water intake ports 47 are formed in the front part of the anti-ventilation plate 41, and a pair of water drain ports 48 are formed in the rear part of the anti-ventilation plate 41. More specifically, the front side of the plate case 42 is divided into left and right, and the pair of water intake ports 47 are formed at the tip of this branching part. A pair of water drain ports 48 connected to the collection section 51 are formed in the rear part of the lower surface of the anti-ventilation plate 41, i.e., in the rear part of the plate cover 43.

[0022] A pair of flow paths 49 are formed inside the anti-ventilation plate 41, leading from a pair of water intakes 47 to a pair of water discharge ports 48. A backflow prevention structure is formed in each flow path 49 between the water intakes 47 and the collection section 51. In this embodiment, a so-called Tesla valve consisting of multiple branch flow paths is used as the backflow prevention structure. The flow from each water intake 47 to each water discharge port 48 is strengthened at the joining point of the branch flow paths, and the flow from each water discharge port 48 to each water intake 47 is weakened at the joining point of the branch flow paths. Note that a mechanical check valve may be provided midway along the water path as the backflow prevention structure.

[0023] When the vessel is traveling forward, water is taken in from each water intake 47, and a flow occurs from each water intake 47 to each water discharge outlet 48 through each flow path 49. When the vessel is traveling backward, the backflow prevention structure of the flow path 49 prevents backflow from each water discharge outlet 48 to each water intake 47. A strainer (not shown) that captures pebbles, algae, etc. is provided in each water intake 47. Therefore, foreign matter such as pebbles and algae is removed from the water flow in each flow path 49. Although a strainer does not have to be provided in each water intake 47, each water intake 47 may be formed of a large number of small holes so that foreign matter that would clog the flow path 49 is not taken in.

[0024] As shown in Figures 4 and 5, the collection section 51 is formed in a generally rectangular shape when viewed from above so as to be able to be pulled out from the anti-ventilation plate 41 (see Figure 3(A)). The rear half of the collection section 51 is a collection section main body 52 with a knob 53 attached, and the front half of the collection section 51 is a holder 61 that is in the shape of a rectangular frame when viewed from above and holds a filter 62. The rear surface of the collection section main body 52 is formed along the outer circumferential surface of the anti-ventilation plate 41, and an arch-shaped knob 53 protrudes from the rear surface of the collection section main body 52. ​​A through hole 54 is formed from the upper surface to the lower surface of the collection section main body 52, and the threaded portion of a wing screw 46 (see Figure 3(B)) is inserted into the through hole 54.

[0025] A pair of cavities 55 opening forward are formed inside the collection section main body 52. ​​A pair of openings 56 are formed on both side walls of the collection section main body 52, and each of the cavities 55 communicates with each of the flow paths 49 (see FIG. 3(A)) through each of the openings 56. A partition wall 57 protrudes forward from the collection section main body 52, and the inside of the holder 61 is divided into left and right by the partition wall 57. A front wall 58 wide in the left-right direction is formed at the tip of the partition wall 57, and the front wall 58 presses the filter 62 against the front frame 66 of the holder 61. A pair of snap-fit ​​claws 59 protrude forward from both side walls of the collection section main body 52, and a pair of protrusions 63 at the rear end of the holder 61 are hooked by the pair of claws 59.

[0026] The rear frame of the holder 61 is formed by an upper beam 64 and a lower beam 65, and the inside of the holder 61 communicates with a pair of cavities 55 of the collection section main body 52 through an opening between the upper beam 64 and the lower beam 65. The filter 62 is attached by the holder 61 and the collection section main body 52. ​​Specifically, the filter 62 is sandwiched between the upper beam 64 of the holder 61 and the upper wall of the collection section main body 52, between the front frame 66 of the holder 61 and the front wall 58 of the collection section main body 52, and between the lower beam 65 of the holder 61 and the lower wall of the collection section main body 52. ​​For this reason, it is possible to replace only the filter 62 from the collection section 51 by removing the holder 61 from the collection section main body 52.

[0027] The filter 62 is a filtering member with a multi-layer structure with different mesh sizes, and is formed so that fine foreign matter such as microplastics can be collected from the water flow by the filter 62. For example, when a net is used as the filter 62, a combination of multiple nets with different mesh sizes is used. The target size of the foreign matter to be collected by the filter 62 is at least a size that can be seen with the naked eye (for example, a diameter of 0.1 mm or more to 0.2 mm or more). In this way, water is taken into the anti-ventilation plate 41 from the water intake 47 as the ship travels forward, and fine foreign matter is removed by the filter 62 near the discharge outlet 48.

[0028] Foreign matter captured by the filter 62 is removed from the anti-ventilation plate 41 by replacing the filter 62. The cartridge-type collection section 51 may be pulled out from the anti-ventilation plate 41 and the filter 62 may be replaced together with the collection section 51, or the filter 62 may be removed from the collection section 51 and only the filter 62 may be replaced. Even if the filter 62 becomes clogged, the flow in each flow path 49 is merely impeded, and the anti-ventilation plate 41 can still perform its original function with little effect on driving performance. For this reason, the filter 62 can be replaced at any time the user desires.

[0029] The water flow in the anti-ventilation plate will be described with reference to Fig. 6 and Fig. 7. Fig. 6 is a diagram showing the water flow when the boat of this embodiment is traveling forward. Fig. 7 is a diagram showing the water flow when the boat of this embodiment is traveling backward.

[0030] As shown in FIG. 6(A), when the ship is traveling forward, water flows into a pair of flow paths 49 from a pair of water intakes 47 at the front of the anti-ventilation plate 41. At this time, large foreign objects such as pebbles are removed by the strainers of each water intake 47. Water flows from each water intake 47 toward the collection unit main body 52, branching and gathering repeatedly through the multiple branch flow paths of the flow path 49. The water flow is strengthened at the gathering point of the multiple branch flow paths (the point where multiple arrows F1 gather) and flows smoothly. Then, water passes from each cavity 55 of the collection unit main body 52 through the inside of the holder 61 and is discharged from each drainage port 48 on the underside of the anti-ventilation plate 41.

[0031] As shown in FIG. 6(B), water flows from each cavity 55 of the collection unit main body 52 into the holder 61, and fine foreign matter C is removed by the filter 62 and discharged from each drainage port 48. At this time, the foreign matter C is likely to accumulate in the front half of the holder 61 due to the influence of the water flowing forward from each cavity 55 of the collection unit 51. Since each drainage port 48 is located in the rear half of the holder 61, the filter 62 is unlikely to become clogged with the foreign matter C near each drainage port 48. In this way, the water taken in from each water intake port 47 is filtered by the filter 62, and fine foreign matter C is collected during normal operation of the ship, thereby implementing environmental measures.

[0032] As shown in Fig. 7(A), when the vessel is traveling backward, water flows from the recovery unit main body 52 toward each water intake 47, repeatedly branching and converging through the multiple branch flow paths of the flow path 49. At the point where the multiple branch flow paths converge (where multiple arrows F2 gather), the flow of water is weakened and backflow is suppressed. In addition, the flow along the outer circumferential surface of the anti-ventilation plate 41 separates in front of the anti-ventilation plate 41, generating a wake F3 such as a Karman vortex. The wake F3 suppresses discharge from each water intake 47, and backflow in the flow path 49 is suppressed.

[0033] As shown in Fig. 7(B), the drainage ports 48 are formed on the underside of the anti-ventilation plate 41, so that the direction of the water flow during reverse driving intersects with the direction of the drainage ports 48, making it difficult for water to flow in through the drainage ports 48. Even if water flows back near the drainage ports 48 and exerts water pressure on the filter 62, the filter 62 swells upward, trapping the foreign matter C that has accumulated in the front half of the holder 61. In this way, the filter 62 is held in the holder 61 with some slack. By preventing backflow from the drainage ports 48 to the water intakes 47, it is difficult for the foreign matter C to flow out of the filter 62.

[0034] As described above, according to this embodiment, the water flow in the flow passage 49 of the anti-ventilation plate 41 passes through the filter 62, thereby removing fine foreign matter such as microplastics from the water flow and implementing a measure to collect the foreign matter while the boat is traveling. In addition, since the anti-ventilation plate 41 is provided with the collection section 51, the running resistance does not increase and the power performance of the outboard motor 1 is not sacrificed either during normal running or high-speed running.

[0035] In this embodiment, the anti-ventilation plate is detachably provided on the outboard motor, but as shown in Fig. 8, the anti-ventilation plate 71 may be integrally provided on the outboard motor 1. This makes it possible to omit the installation work of the anti-ventilation plate 71.

[0036] In this embodiment, no airflow straightening device is provided on the anti-ventilation plate, but as shown in Fig. 9, a course keeper 76 may be detachably provided as an airflow straightening device on the anti-ventilation plate 41. A stabilizer or a propeller guard may also be provided as the airflow straightening device. This facilitates the installation of the airflow straightening device, and simplifies the maintenance of the airflow straightening device.

[0037] In addition, in this embodiment, because the anti-ventilation plate is detachably provided on the outboard motor, anti-ventilation plates with different front-to-rear lengths may be used for a single propeller and a dual propeller (contra-rotating propellers). This allows the gear case and heat sink to be used for both the single propeller and the dual propeller. Also, because the anti-ventilation plate is manufactured separately, the size of the mold does not increase when manufacturing the gear case and heat sink.

[0038] In addition, in this embodiment, the anti-ventilation plate is attached to the heat sink of the outboard motor, but the attachment position of the anti-ventilation plate is not particularly limited. For example, the anti-ventilation plate may be attached to the gear case of the outboard motor.

[0039] In addition, in this embodiment, the anti-ventilation plate extends horizontally from the heat sink, but the horizontal direction is not limited to a direction completely perpendicular to the vertical direction, but also includes a direction that is slightly inclined to the extent that it can be considered to be substantially perpendicular to the vertical direction.

[0040] In addition, in this embodiment, the anti-ventilation plate is formed in a flat plate shape, but the shape of the anti-ventilation plate is not particularly limited as long as it performs the anti-ventilation function.

[0041] In addition, while the purpose of this embodiment is to remove foreign matter such as microplastics, for fish farmers, the filter can also effectively remove leftover feed and other contaminants in addition to microplastics, thereby contributing to the prevention of marine pollution.

[0042] The anti-ventilation plate may also be called a ventilation plate, an anti-cavitation plate, or a cavitation plate.

[0043] In the present embodiment, the collection section is formed in a cartridge type, but the collection section is not limited to the cartridge type, and only the filter of the collection section may be formed so as to be replaceable.

[0044] Further, in this embodiment, a filter having a multi-layer structure is used, but a filter having a single layer structure may be used as long as it is capable of capturing fine foreign matter.

[0045] In addition, in this embodiment, a backflow prevention structure is formed in the flow path, but the flow path does not necessarily have to be formed with a backflow prevention structure. Backflow can also be prevented by the wake of Karman vortexes, the position of the drain port, etc.

[0046] In addition, in this embodiment, the filter is provided near the drain outlet, but the filter may be provided anywhere between the water intake and the drain outlet.

[0047] As described above, the foreign object recovery device (40) of this embodiment is a foreign object recovery device provided in a marine propulsion unit (outboard motor 1) that provides a propulsive force to a hull, and includes an anti-ventilation plate (41) that extends in the horizontal direction and a recovery section (51) provided in the anti-ventilation plate. A flow path (49) is formed in the anti-ventilation plate from the water intake (47) to the water discharge port (48), and a filter (62) capable of recovering fine foreign objects from the water flow in the flow path is provided in the recovery section. According to this configuration, the water flow in the flow path of the anti-ventilation plate passes through the filter, thereby removing fine foreign objects such as microplastics from the water flow, and a recovery measure for foreign objects is implemented while the marine vessel is traveling. In addition, since the recovery section is provided in the anti-ventilation plate, the running resistance is not increased during normal traveling and high-speed traveling, and the power performance of the marine propulsion unit is not sacrificed.

[0048] In the foreign object recovery device of this embodiment, a recovery section is provided at the rear of the anti-ventilation plate, a water intake is formed at the front of the anti-ventilation plate, and a discharge port connected to the recovery section is formed at the rear of the anti-ventilation plate. With this configuration, water is taken in from the water intake into the anti-ventilation plate as the ship travels forward, and fine foreign objects can be removed from the water flow near the discharge port.

[0049] In the foreign object recovery device of this embodiment, the anti-ventilation plate is formed in a flat plate shape, which makes it possible to suppress an increase in running resistance caused by the anti-ventilation.

[0050] In the foreign object recovery device of this embodiment, a backflow prevention structure is formed in the flow passage of the anti-ventilation plate between the water intake and the recovery section. With this configuration, the backflow prevention structure of the flow passage prevents backflow from the discharge port to the water intake when the ship is traveling in reverse.

[0051] In the foreign matter recovery device of this embodiment, the recovery section is a cartridge type, and the filter is a filtering member with a multi-layer structure with different mesh sizes. With this configuration, the filter can effectively remove fine foreign matter from the water flow. In addition, because the recovery section is a cartridge type, the filter replacement work can be simplified.

[0052] In the foreign object recovery device of this embodiment, the anti-ventilation plate is provided integrally with the marine vessel propulsion device, which makes it possible to omit the installation work of the anti-ventilation plate.

[0053] In the foreign object recovery device of this embodiment, the anti-ventilation plate is detachably provided on the marine propulsion device. With this configuration, the gear case and the heat sink can be used for both the single propeller and the dual propeller. In addition, the size of the mold used to manufacture the gear case and the heat sink does not become large.

[0054] In the foreign object recovery device of this embodiment, the flow straightening device (course keeper 76) is detachable from the anti-ventilation plate. This configuration makes it easy to install the flow straightening device, and facilitates maintenance of the flow straightening device.

[0055] Although the present embodiment has been described, other embodiments may be made by combining the above-described embodiments and modifications in whole or in part.

[0056] In addition, the technology of the present invention is not limited to the above examples, and may be modified, substituted, or altered in various ways without departing from the spirit of the technical idea. Furthermore, if the technical idea can be realized in a different way due to the progress of technology or a different technology derived therefrom, the invention may be implemented using that method. Therefore, the claims cover all embodiments that may be included within the scope of the technical idea. [Explanation of symbols]

[0057] 1: Outboard motor (marine propulsion unit) 34: Propeller 40: Foreign object collection device 41, 71, 75: Anti-ventilation plate 47: Water intake 48:Drain port 49: Flow path 51: Collection Department 62: Filter 76: Course keeper (straightening device)

Claims

1. A foreign object recovery device provided in a ship propulsion device that provides a propulsive force to a ship hull, A horizontally extending anti-ventilation plate and A collection section provided at the rear of the anti-ventilation plate, A flow path is formed in the anti-ventilation plate from the water intake port to the water discharge port, The foreign matter recovery device is characterized in that the recovery section is provided with a filter capable of recovering fine foreign matter from the water flow in the flow path.

2. A foreign matter collection device as described in Claim 1, characterized in that the water intake port is formed at the front part of the anti-ventilation plate, and the drain outlet connected to the collection section is formed at the rear part of the anti-ventilation plate.

3. 3. The foreign object recovery device according to claim 1, wherein the anti-ventilation plate is formed in a flat plate shape.

4. 4. The foreign object recovery device according to claim 1, wherein a backflow prevention structure is formed in the flow path of the anti-ventilation plate between the water intake and the recovery section.

5. 5. The foreign matter recovery device according to claim 1, wherein the recovery section is of a cartridge type, and the filter is a filtering member having a multi-layer structure with different mesh sizes.

6. 6. The foreign object recovery device according to claim 1, wherein the anti-ventilation plate is provided integrally with the marine vessel propulsion device.

7. 6. The foreign object recovery device according to claim 1, wherein the anti-ventilation plate is detachably provided on the marine propulsion device.

8. 8. The foreign matter recovery device according to claim 1, wherein a straightening device is detachably attached to the anti-ventilation plate.

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