JP2013199217A - Amphibious vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an amphibious vehicle capable of reducing various resistances during on-water driving and suppressing adhesion of submerged aquatic plants, etc. with a simple structure and low manufacturing cost.SOLUTION: An amphibious vehicle 1 has a body, front wheels 41, and rear wheels 46. The left/right rear wheels are rotatably supported by rear-wheel axle shafts 47A and 47B attached to a bottom surface of the body. A propelling device 60 for on-water driving is attached to a back of the rear-wheel axle shafts. The amphibious vehicle is provided with a rear under cover 80 which is divided to the front and back to cover the peripheries of the rear-wheel axle shafts from the lower side while exposing the rear wheels to allow driving. In the rear under cover, a rear-part tilt surface 85 extending to the rear and upper side from the position covering the peripheries of the rear-wheel axle shafts is formed. The rear-part tilt surface is configured so as to be able to guide water streams toward the propelling device upon on-water driving.

Description

  The present invention relates to an amphibious vehicle capable of running on land and traveling on water.

  There are two types of amphibious vehicles: a type that uses an automobile (vehicle) as a basic structure to enable water navigation, and a type that uses a ship as a basic structure to enable land travel. The difference between the two types depends on whether the emphasis is on land driving or water navigation. Recently, many amphibious vehicles that use automobiles as the basic structure have been provided. As an amphibious vehicle of the type that employs such an automobile as a basic structure, an amphibious vehicle having a water navigation screw (propulsion device) on the rear outer surface of the vehicle body is known.

  In general, a complex uneven structure exists on the outer surface of the bottom of a vehicle body in an automobile. This is because the engine, power transmission device (clutch, transmission, screw shaft, differential gear, axle to which the wheel is connected, etc.) and suspension device (suspension), and the wheel, etc. attached to the frame are exposed to the road surface. This is due to the fact that

On the other hand, at the time of water navigation, the density of water is about 800 times larger than that of air, and the water resistance, that is, the viscous pressure resistance, the frictional resistance, and the wave generation are mainly lower than the waterline including the bottom structure of the amphibious vehicle. Since resistance acts, it will increase significantly compared to the resistance caused by air when running on land. And these various resistances increase further when a complicated uneven structure increases on the bottom outer surface of an amphibious vehicle.
In addition, propellers such as propellers installed at the stern for underwater navigation operate in a turbulent flow caused by the uneven shape of the hull, so the propulsion efficiency is lower than when placed in a uniform flow The propulsion performance is also adversely affected.

  In order to reduce various resistances when sailing on the water, a technology that makes the wheels of amphibious vehicles retractable and covers the wheels, frames, axles, suspensions, etc. with a movable buoyancy cover by a link mechanism Has been proposed (Patent Document 1).

Japanese Patent Laid-Open No. 2005-53434

  However, in order to reduce various resistances when navigating on the water, the wheels are retracted and covered with a movable cover such as a link mechanism. )), And the structure of the amphibious vehicle becomes complicated, increasing the total weight and increasing the manufacturing cost.

Also, when underwater plants such as algae or seaweeds are breeding in the water, various types of garbage are floating, and the axles and suspensions are exposed at the bottom of amphibious vehicles, Since these underwater plants and garbage adhere to the part, they had to be removed manually after the landing of the amphibious vehicle.
However, the above-mentioned conventional amphibious vehicle has a problem that it is difficult to effectively prevent underwater plants and the like from adhering to the axle or the like during water navigation.

  The present invention has been made to solve each of the above-mentioned problems, and it is possible to reduce various resistances during water navigation and to suppress adhesion of underwater plants, etc., with a simple structure and low manufacturing cost. The purpose is to provide an amphibious vehicle.

  In order to solve the above problems, an amphibious vehicle of the present invention has a body, left and right front wheels and left and right rear wheels that support the body, and the left and right rear wheels are attached to the bottom surface of the body. And an at least one water navigation propulsion device mounted on the rear side of the rear wheel axle so as to be able to travel on the rear wheel. A rear under cover is provided to cover at least a part of the bottom surface of the body from below while being exposed, and the rear under cover is formed by being divided in the front-rear direction, sandwiching the rear wheel axle, and The rear rear under cover is provided so as to be flush with the rear wheel axle, and an inclined surface extending rearward and upward is formed, and the inclined surface is at least in water navigation. One of the is characterized in that it is configured to be guided water flow toward the propulsion device.

Here, flush means that the front and rear rear undercovers adjacent to each other and the surface of the rear wheel axle are formed on the same surface, but are not necessarily the same surface, and are formed on substantially the same surface. If it is,
Further, the propulsion device includes various aspects such as an outboard motor having a screw, an inboard / outboard motor and an inboard motor, and a water jet injection device.

According to the present invention, the rear under cover that covers at least a part of the bottom surface of the body and the rear wheel axle from below is provided with the rear wheel exposed to be able to travel, so that a complicated unevenness is formed on the bottom of the body. Compared to the case where the structure is exposed, water flows smoothly along the outer surface of the bottom surface of the rear under cover, reducing various resistances during water navigation and improving the propulsion efficiency for efficient underwater driving. Is possible.
Further, the rear under cover is formed by being divided in the front-rear direction, sandwiching the rear wheel axle, and provided so as to be flush with the rear wheel axle. It can be easily attached in accordance with the above.

  In addition, when a complex uneven structure is exposed behind the bottom of the body of an amphibious vehicle, it is difficult to smoothly guide the water flow to the propulsion device because a large vortex is generated in the water flow during water navigation. However, according to the present invention, the rear under cover has an inclined surface extending rearward and upward from a position covering the rear wheel axle, and the inclined surface is directed toward the at least one screw during water navigation. Since it is possible to guide the water flow, it becomes one factor that can improve the rotation efficiency of the propulsion device.

In addition, the presence of the rear under cover does not expose a complicated uneven structure at the bottom of the body, so that underwater plants or the like can be prevented from adhering during water navigation.
Furthermore, since the air resistance can be reduced even when traveling on land, it is possible to improve fuel efficiency.

Also, even if the rear wheels are not retractable and equipped with a rear under cover, the rear wheels remain exposed to the road surface without being covered by the rear under cover. It can be performed, and in shallow water, it is possible to travel using the wheels in water as necessary.
Furthermore, compared with the conventional amphibious vehicle, a complicated structure is not required, and the rear under cover can be realized with a simple structure, so that the total weight is not increased and it can be manufactured at a low cost.

  In the amphibious vehicle of the present invention, the left and right front wheels are supported by a front wheel axle attached to the bottom surface of the body, and the bottom surface of the body is exposed to be able to travel. A front under cover is provided to cover at least a part of the front under cover, and the front under cover is formed by being divided in the front-rear direction so as to sandwich the front wheel axle and be flush with the front wheel axle. It can be set as the structure provided facing.

  According to the present invention, the front under cover is provided so as to cover at least a part of the bottom surface of the body and the front wheel axle from below while the front wheels are exposed to be able to travel, so that a complicated uneven structure is formed on the bottom of the body. Compared with the case where it is exposed, water flows smoothly along the outer surface of the bottom surface of the front under cover, so that various resistances during water navigation can be reduced, and efficient underwater travel is possible.

Further, the front under cover is formed by dividing it in the front-rear direction, sandwiches the front wheel axle, and is provided so as to be flush with the front wheel axle. And can be easily attached.
Furthermore, the presence of the front under cover does not expose a complicated uneven structure at the bottom of the body, so that underwater plants and the like can be prevented from adhering during water navigation.

  Furthermore, in the amphibious vehicle of the present invention, the front under cover is formed so as to be integrated with the bumper of the amphibious vehicle, and can be streamlined with the bumper.

  According to the present invention, it is possible not only to divide the water flow into left and right but also to smoothly guide it downward, so that various resistances can be further reduced.

  ADVANTAGE OF THE INVENTION According to this invention, the amphibious vehicle which can aim at reduction of various resistance at the time of surface navigation and suppression of adhesion of an underwater plant etc. can be provided with simple structure and low manufacturing cost.

1 is a side view of an amphibious vehicle according to a first embodiment of the present invention. It is a side view of the body of the amphibious vehicle in 1st Embodiment of this invention. It is a bottom view of the amphibious vehicle in 1st Embodiment of this invention. It is explanatory drawing for demonstrating the positional relationship of the propulsion apparatus and rear undercover in the amphibious vehicle in 1st Embodiment of this invention. 1 is a perspective view of a front under cover and a rear under cover of an amphibious vehicle according to a first embodiment of the present invention. It is a perspective view from the left front lower part of the amphibious vehicle in 1st Embodiment of this invention. It is a perspective view from the left front lower part in the state which removed the undercover of the amphibious vehicle in 2nd Embodiment of this invention. It is a side view of the amphibious vehicle in 3rd Embodiment of this invention. It is a perspective view from the left front lower part of the amphibious vehicle in 3rd Embodiment of this invention. It is a perspective view of the front undercover and bumper of the amphibious vehicle in 3rd Embodiment of this invention. It is explanatory drawing for demonstrating the positional relationship of the propulsion apparatus and rear undercover in the amphibious vehicle in 4th Embodiment of this invention.

The amphibious vehicle of the present invention will be described in detail with reference to the drawings. In the following description, the same reference numerals are assigned to the same devices and the like, and duplicate descriptions are omitted.
In the following description, unless otherwise specified, the front-rear direction and the left-right direction refer to directions with respect to the traveling direction.

[1] First Embodiment (1) Basic Structure A first embodiment of an amphibious vehicle 1 of the present invention will be described.
As shown in FIGS. 1 and 3, the amphibious vehicle 1 includes a body B having a substantially box shape and an internal space, and a front wheel 41 attached to the body B via a front frame 20 and a rear frame 25. And a rear wheel 46.
On the deck of the body B, a driver's cab 98 is provided at the front, and a cabin 99 having a roof, a seat, and the like is provided at the rear.

(2) Body As shown in FIG. 2, the body B is formed in an elongated box shape having a sealed internal space and has a watertight structure capable of floating on the water. A front surface portion B1, a rear surface portion B3 which is a mounting portion of the rear wheel 46, a stern portion B4 behind the rear surface portion B3, and an intermediate portion B2 between the front surface portion B1 and the rear surface portion B3. .

  The body B includes a rectangular body upper surface member 11 (which constitutes a deck), left and right body side members 12, 13, a mountain-shaped body front member 14 (in plan view), and a lower edge of the body side surface. Formed by joining a hat-shaped body bottom member 15 (side view) and a hexagonal body rear surface member 16 having a substantially lower bottom end portion of the home base joined together. (However, the structure of the stern part B4 will be described later).

  The body upper surface member 11 is provided at a position lower than the upper ends of the left and right body side surface members 12 and 13, the body front surface member 14 and the body rear surface member 16. A space is formed. In addition, the body upper surface member 11 has a front portion compared to the rear portion at a substantially central portion in order to secure an installation space for the engine 56 and the like, and to increase a reserve buoyancy and maintain a restoring force in water. Highly formed.

  The front part B1 is formed from the body front member 14, the front parts of the left and right body side members 12, 13, the front part of the body top member 11, and the front part of the body bottom member 15 (each about one third of the total length). It is the part that is formed. A front lower space 7 is formed in the entire vehicle width direction in a portion from the front end of the body B to the vicinity of the rear end of the front wheel 41 below the front surface B1. The front lower space 7 has a height slightly longer than the radius of the front wheel 41.

The front body member 14 is formed in a mountain shape (plan view) in which the center of the tip protrudes and has an arcuate isosceles triangle shape so that the water flow is divided into left and right to reduce various resistances. .
The left and right body side members 12 and 13 corresponding to the front surface portion B1 have a slightly protruding front end portion and a rear end portion of 1 from the front lower end portion to the vicinity of the rear end portion of the front wheel 41 in a side view. / 4 It is shaped by cutting out a substantially rectangular part that is circular.

  The central part B2 includes projecting portions of the left and right body side members 12 and 13 (each about one third of the total length), and the body top surface member 11 and the body bottom surface member 15 corresponding to the body side surface members 12 and 13, respectively. It is a part formed from Further, the body bottom member 15 is formed so as to incline gently so as to become narrower from the left-right direction to the lower side.

  The rear surface portion B3 is a portion formed from the rear portion of the body rear surface member 16, the rear portions of the left and right body side members 12, 13, the rear portion of the body upper surface member 11, and the rear portion of the body bottom surface member 15. A rear lower space portion 8 is formed in the vehicle width direction below the rear surface portion B3. The height of the rear lower space 8 is slightly longer than the radius of the rear wheel 46.

The left and right body side members 12 and 13 corresponding to the rear surface portion B3 have a shape in which semicircular portions are deleted along the shape of the rear wheel 46 in a side view in the vicinity of the rear end portion of the rear wheel 46. Is formed.
The body rear surface member 16 forms a boundary between the rear surface portion B3 and the stern portion B4, and stands vertically with respect to the rear end portion of the body bottom surface member 15.

  The stern portion B4 is formed of left and right floating bodies 19 provided in the body rear surface member 16 connected to the left and right body side surface members 12 and 13, and a stern member 18 having an inverted concave shape. A rear space portion 9 for installing the propulsion device 60 is formed between the left and right floating bodies 19, and this rear space portion 9 is continuous with the rear lower space portion 8 of the rear surface portion B3 of the body B. ing.

Note that the rear end portions of the left and right body side members 12 and 13 are trapezoidal in a side view so that an upward inclined surface is formed toward the rear so that the water flow can be smoothly guided rearward. Presents.
A tail lamp 32 is attached to the stern member 18.

(3) Front frame, rear frame and bumper As shown in FIG. 3, the front frame 20 is a frame member (plan view) formed of channel steel provided to attach the front wheel axle 42. The side rails 21A and 21B are arranged in parallel in the front-rear direction at a predetermined interval, and the cross members 22A and 22B are arranged in parallel in the vehicle width direction at a predetermined interval. The front frame 20 is attached to the front lower space 7 of the body B by a bolt (not shown).

  The rear frame 25 is a frame member formed of grooved steel provided to attach the rear wheel axles 47A, 47B, and side rails 26A, 26B arranged in parallel in the front-rear direction at a predetermined interval. The cross members 27A and 27B are arranged in parallel in the width direction at a predetermined interval. The rear frame 25 is attached to the rear lower space 8 of the body B with a bolt (not shown).

The bumper 30 is provided below the front end surface of the front frame 20 and along the front end portion of the body bottom surface member 15. The bumper 30 is substantially V-shaped in a plan view, and the tip of the central portion protrudes in a plan view so as to follow the shape of the body front member 14, and two sides are formed symmetrically in an arc shape.
Further, headlamps 31 each having a substantially rectangular parallelepiped box shape are attached to the left and right ends of the bumper 30.
In addition, two reinforcing members 33 for reinforcing the part are laterally provided at the tip of the body B.

(4) Engine and Power Transmission Device As shown in FIG. 3, the engine 50 is installed in the inner space of the central portion B2 of the body B in order to prevent it from being exposed to seawater or the like during cruising and rusting. . A clutch 51 and a transmission 52, which are connected to the output shaft of the engine 50 and constitute a power transmission device in order toward the rear, are provided in the internal space. The output shaft of the transmission 52 is connected to the front end portion of the screw shaft 53 extending in the traveling direction of the body B, and the rear end portion of the screw shaft 53 is connected to the input shaft of the differential device 54.

The front portion of the screw shaft 53 is installed in the internal space of the body B. Further, the screw shaft 53 extends in a state of protruding from the lower part of the center part B2 of the body B to the rear lower space 8 while maintaining the water tightness of the body B.
Rear wheel axles 47A and 47B, which are drive shafts, are rotatably connected to the left and right of the differential device 54 in the vehicle width direction. The differential 54 is attached to the rear frame 25 and protrudes into the rear lower space 8.
The rear wheel axles 47A and 47B are pivotally supported by the side rails 26A and 26B of the rear frame 25, and two rear wheels 46 are provided at both ends of the rear wheel axles 47A and 47B. .

  The front wheel axle 42 is pivotally supported on the side rails 21 </ b> A and 21 </ b> B of the front frame 20, and one front wheel 41 is provided at each end of the front wheel axle 42. Further, the front wheel axle 42 can be steered by changing its direction in the left-right direction by a steering means (not shown).

  In order to support the front wheel axle 42 from below, a parallel leaf spring suspension 44 (hereinafter referred to as “leaf spring”) extends along the side rails 21A and 21B of the front frame 20. . Similarly, leaf springs 49 are extended along the side rails 26A and 26B of the rear frame 25 to support the rear wheel axles 47A and 47B from below.

(5) Propulsion Device As shown in FIG. 4, the amphibious vehicle 1 includes two propulsion devices 60 for navigating on the water. The propulsion device 60 is a known outboard motor, and includes a columnar body body 61 and a screw 62 at the tip thereof.

The airframe body 61 is mounted to be steerable in the left and right directions via a swivel bracket 64. The swivel bracket 64 is supported by the clamp bracket 65 so as to be swingable up and down around the tilt axis t. The crank bracket 64 is fixed to the upper edge portion of the support member 28 joined to the rear end portion of the rear frame 25 described later.
The screw 62 includes three screw blades 62a, and is pivoted so that the tip of the main body is vertical and the screw blades 62a face rearward when chilled.

  A cavitation plate 63 is provided laterally immediately above the screw 62 a in the machine body 61.

  Due to the above structure, the propulsion device 60 is capable of water navigation and land travel by tilting down during water travel and tilting up to prevent damage to the screw blades 62a and the like during land travel.

(6) Bottom structure of body Next, the bottom structure of the body B of the amphibious vehicle 1 will be described. In the amphibious vehicle 1, the front lower space portion 7 and the rear lower space portion 8 are closed by a front under cover 70 and a rear under cover 80, respectively.

a) Front Undercover As shown in FIG. 5, the front undercover 70 covers the uneven structure at the bottom of the front surface of the body B, and is in close contact with the bumper 30 and the body bottom surface member 15, so that it is smooth as a whole. As a smooth structure having a shape, it has a function of reducing various resistances, and is formed in a thin plate structure made of metal or resin. The front under cover 70 may be corrugated in the flow direction to give strength.

  The front under cover 70 is formed of a front front under cover 70f and a rear front under cover 70r. The front under cover 70 has notches 75 and 76 corresponding to the left and right leaf springs 44 and corresponds to the front wheel axle 42. The portion to be divided has a structure divided into two in the front-rear direction.

  The front front under cover 70f has an arrow shape in plan view, and is joined to the bottom of the bumper 30 with a bolt (not shown).

  The rear front under cover 70r is composed of a rear bottom surface portion 74 and a rear side surface portion 77 obliquely provided on the left and right of the rear end portion of the rear bottom surface portion 74. The left and right side surface portions 77 have a shape that is gently inclined so as to be in close contact with the body bottom surface member 15, and the upper end portions thereof are joined to the rear end portions of the front lower space portion 7 with bolts (not shown).

  Then, as shown in FIG. 6, the front front under cover 70f and the rear front under cover 70r do not cover the front wheel axle 42, face the front wheel axle 42 and face each other so as to be flush with each other. It is attached to the body bottom member 15 with a bolt so as to close the portion 7.

  When the distance between the lower surface of the body B and the ground contact surface of the front wheel 41 is small during running on land, there is a possibility that the driving may be hindered due to contact with pebbles or dust, or the front under cover 70 may be damaged. On the other hand, if this distance is large, the resistance also increases. Therefore, this distance is preferably designed in consideration of these balances.

b) Rear Under Cover As shown in FIG. 5, the rear under cover 80 covers the concavo-convex structure on the lower surface of the body B, and the front end is in close contact with the body bottom surface member 15. It has a function of reducing various resistances as a structure, and is formed in a thin plate structure made of metal or resin.

  The rear under cover 80 is formed of a front rear under cover 80f and a rear rear under cover 80r, and is provided with notches 86 and 87 corresponding to the left and right leaf springs 49, and the rear axle 47A, In the part where 47B is located, it has the structure divided into two in the front-back direction.

  The front rear under cover 80f is formed of a front horizontal portion 82 having a substantially concave shape, and left and right front side portions 81 provided at both ends thereof. A trapezoidal opening 88 corresponding to a part of the screw shaft 53 and the differential 54 is formed at the center of the rear end portion of the front horizontal portion 82. Further, notches 86 corresponding to the leaf springs 49 are formed at the left and right rear side ends of the front horizontal portion 82.

  Further, the rear rear under cover 80r is provided at both ends of the rear horizontal portion 83 having a rectangular shape, a rectangular rear inclined surface 85 connected to the rear horizontal portion 83, and the rear inclined surface 85. The left and right rear side surfaces 84 are formed. A notch 87 corresponding to the leaf spring 49 is formed at the front edge of the rear inclined surface 85.

  As shown in FIG. 6, the front rear under cover 80f and the rear rear under cover 80r do not cover the rear wheel axles 47A and 47B, and face each other so as to be flush with each other with the rear wheel axles 47A and 47B interposed therebetween. The body bottom surface portion 15 is attached so as to close the rear lower space portion 8.

  The leaf springs 44 and 49 slightly protrude downward from the front under cover 70 and the rear under cover 80 due to the structure thereof.

  By the way, as shown in FIG. 4, when the circular diameter of the rotating locus of the screw blades 62a is D (in this case, twice the length of the screw blades 62a is D), the rear rear under The rear end portion of the rear inclined surface 85 of the cover 80r is preferably provided so as to be slightly higher than the cavitation plate 63 or higher than D / 4. In this case, the angle θ between the rear inclined surface 85 of the rear rear under cover 80r and the horizontal line obtained by horizontally extending the cavitation plate 63 needs to be as small as possible, but is preferably 10 to 35 degrees.

By providing the position of the rear end portion of the rear inclined surface 85 of the rear rear under cover 80r in this manner, the rear inclined surface 85 of the rear rear under cover 80r can smoothly guide the water flow toward the screw 62. It has become.
Further, the inclination angle formed by the rear inclined surface 85 of the rear rear under cover 80r and the rear horizontal surface 83 is set to about 15 degrees in the present embodiment, and the water flow is separated from the inclined surface by the steep angle. Disturbance of water flow is suppressed.

  When the distance between the front horizontal surface 82 and the rear horizontal surface 83 of the rear under cover 80 and the ground contact surface of the rear wheel 46 is small during land travel, the rear under cover 80 may come in contact with pebbles or dust and hinder travel. May be damaged. Therefore, this distance is preferably designed in consideration of this point. The height of the rear under cover 80 is preferably designed so that the angle of the water flow to the propeller is 10 degrees to 35 degrees with respect to the horizontal line.

(7) Operational Effects Next, operational effects of the amphibious vehicle 1 will be described.
As shown in FIG. 1, when the amphibious vehicle 1 sails on the water, the front lower space portion 7 and the rear lower space portion 8 of the body B are below the draft line W. At this time, since water smoothly flows along the bottom surface portion of the front under cover 70 toward the center portion of the body bottom surface member 15, various resistances due to the uneven structure of the front lower space portion 7 of the body B can be reduced. .

  Similarly, the rear under cover 80 can reduce the uneven structure of the rear lower space 8 of the body B, that is, various resistances caused by a part of the screw shaft 53, the differential device 54, and the like.

Although the front under cover 70 does not cover the front wheel axle 42, the front front under cover 70f and the rear front under cover 70r are provided to face each other with the front wheel axle 42 in between. Therefore, the function of reducing various resistances is not impaired (the same applies to the rear under cover 80).
Further, the leaf springs 44 and 49 are only slightly protruded from the bottom surfaces of the front under cover 70 and the rear under cover 80, and the shape thereof is also a smooth curved surface in the traveling direction, so that various resistances can be reduced. Will not be damaged.

  Further, the rear rear under cover 80r has a rear inclined surface 85, and has a structure for smoothly guiding the water flow toward the screw blades 62a of the propulsion device 60 tilted down, thereby improving the rotational efficiency of the screw blades 62a. Can be made.

  Further, the presence of the front under cover 70 and the rear under cover 80 can suppress the attachment of underwater plants to the screw shaft 53 and the differential 54 and the like.

Furthermore, since the front under cover 70 and the rear under cover 80 are detachable by bolts, it is possible to facilitate the inspection of the front wheel axle 42 and the rear wheel axles 47A and 47B.
The front under cover 70 and the rear under cover 80 are very suitable because they can be easily attached to various existing amphibious vehicles.

[2] Second Embodiment Next, a second embodiment of the amphibious vehicle of the present invention will be described with reference to FIG.
The amphibious vehicle 2 of the second embodiment has the same basic configuration as the amphibious vehicle 1 of the first embodiment, but the rear front under cover and the front rear under cover are integrated into an under cover 90. The difference is that it is formed. In this under cover 90, a connection middle in which both side surfaces of the rear front under cover 70r similar to the first embodiment and both side surfaces of the front rear under cover 80f similar to the first embodiment are in the shape of an elongated rectangle. Joined by an under cover 90a (a space is formed on the bottom surface).

  According to the amphibious vehicle 2 of the second embodiment, even when the left and right side surfaces are not formed gently, the water flows smoothly and continuously along the bottom surface of the under cover 90. Therefore, various resistances can be further reduced. Moreover, since the undercover 90 can be integrally molded, the manufacturing process can be simplified.

[3] Third Embodiment Next, a third embodiment of the amphibious vehicle of the present invention will be described with reference to FIGS.
The amphibious vehicle 3 according to the third embodiment has the same basic configuration as the amphibious vehicle 1 according to the first embodiment except that the front under cover 70 is formed integrally with the bumper 30. doing. The front under cover 70 is streamlined with the bumper 30. Specifically, a front front under cover 70 f is provided continuously with the bumper 30. The front front under cover 70f and the bumper 30 are integrally formed in a streamlined downward and rearward direction. Therefore, the front front under cover 70f and the bumper 30 are curved in a side view as shown in FIG.

  According to the amphibious vehicle 3 of the third embodiment, the front under cover 70 is formed integrally with the bumper 30 and forms a streamline with the bumper 30, so that the water flow is not only divided into left and right but also smoothly guided downward. Can do. Thereby, various resistances can be further reduced. Further, since the front under cover 70 and the bumper 30 can be integrally molded, the manufacturing process can be simplified.

[4] Fourth Embodiment Next, a fourth embodiment of the amphibious vehicle of the present invention will be described with reference to FIG.
The amphibious vehicle according to the fourth embodiment has the same basic configuration as the amphibious vehicle 1 according to the first embodiment, but differs in that the propulsion device 60 ′ is not an outboard motor but an inboard motor. doing. That is, a screw blade 62a ′ that rotates from a driving force source (not shown) disposed in the internal space of the body B via a screw shaft 64 ′ and a bearing 65 ′ is provided. And it is comprised by the rudder of the back of the advancing direction of screw wing | blade 62a '(not shown) so that it can rotate right and left centering | focusing on a vertical axis according to the advancing direction of the amphibious vehicle 2. FIG. The bearing 65 'is supported by a metallic shaft bracket 66' that is attached to a support member 28 'that is attached to a rear frame (not shown).

Since the vertical position of the propulsion device does not move, the rear end surface 85 'of the rear under cover 80' in this case is located above the screw blades 62a '. The distance H ′ between the rear inclined surface 85 ′ of the rear under cover 80 ′ and the screw blade 62 a ′ is very important from the viewpoint of preventing vibrations. If the diameter of the screw blade 62 a ′ is D ′, 15D ′ / It is necessary to set it to 100 or more (more preferably 25D ′ / 100 or more).
Furthermore, the inclination angle θ ′ formed by the rear inclined surface 85 ′ of the rear under cover 80 ′ and the horizontal plane (not shown) is steep to prevent the water flow from being separated from the inclined surface and disturbing the water flow. Is preferably 10 to 35 degrees.

  Also by the amphibious vehicle of 4th Embodiment, it becomes possible to show | play the effect similar to the amphibious vehicle 1 of 1st Embodiment.

  As mentioned above, although an example about a suitable embodiment was explained about the present invention, the present invention is not restricted to each above-mentioned embodiment, and can change a design suitably in the range which does not deviate from the meaning of the present invention.

  For example, in each of the above embodiments, an arbitrary number of screws may be attached at arbitrary positions as long as they are behind the rear wheel. However, in this case, the shape of the front under cover and the rear under cover needs to be a shape that smoothly guides the water flow to at least a part of the screws. An additional rectifying member can also be provided.

Further, the front under cover and the rear under cover may have either a watertight structure or a non-watertight structure. In the case of the non-watertight structure, the area can be reduced as compared with the case of the watertight structure, so that the weight can be reduced and the manufacturing can be facilitated and the cost can be reduced.
Further, the shape, quantity, mounting position, etc. of various devices including the front under cover and the rear under cover can be selected widely.

  Furthermore, a predetermined member having a watertight structure between the front under cover and the body or a part of the space between the rear under cover and the body is provided. It may be enclosed and stored. Thereby, further buoyancy can be ensured.

Further, the shape of the body, the shape of the bumper, the shape of the suspension, the number of wheels, and other detailed structures in an amphibious vehicle can be modified by the base vehicle body.
Furthermore, the amphibious vehicle is not limited to the rear wheel drive, but may be a front wheel drive or an all-wheel drive.

1, 2, 3 Amphibious vehicle B Body B1 Front part B2 Middle part B3 Rear part B4 Stern part 7 Front lower space part 8 Rear lower space part 9 Rear space part 12, 13 Body side member 14 Body front member 15 Body bottom face Member 20 Front frame 25 Rear frame 41 Front wheel 42 Front wheel axle 46 Rear wheel 47A, 47B Rear wheel axle 60, 60 'Propulsion device 61 Airframe body 62 Screw 62a, 62a' Screw blade 70 Front under cover 70f Front front under cover 70r Rear front under cover 80 Rear under cover 80f Front rear under cover 80r Rear rear under cover 90 Under cover 90a Connection intermediate under cover

Claims (3)

A body, and left and right front wheels and left and right rear wheels that support the body;
The left and right rear wheels are pivotally supported on a rear wheel axle attached to the bottom surface of the body,
At least one water navigation propulsion device is an amphibious vehicle mounted behind the rear axle,
A rear under cover that covers at least a part of the bottom surface of the body from below is provided with the rear wheel exposed to be able to travel,
The rear under cover is formed by being divided in the front-rear direction, sandwiched between the rear wheel axles, and provided so as to be flush with the rear wheel axles,
The rear rear under cover is formed with an inclined surface extending rearward and upward, and the inclined surface is configured to be capable of guiding a water flow toward at least one propulsion device during water navigation. An amphibious vehicle characterized by that. The left and right front wheels are pivotally supported on a front wheel axle attached to the bottom surface of the body,
A front under cover is provided to cover at least a part of the bottom surface of the body from below while leaving the front wheels exposed to travel.
2. The front under cover is formed by being divided in the front-rear direction, and is provided so as to sandwich the front wheel axle and to be flush with the front wheel axle. Amphibious car.   The amphibious vehicle according to claim 2, wherein the front undercover is formed integrally with a bumper of the amphibious vehicle, and forms a streamline with the bumper.

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