To provide an amphibious vehicle that can reduce wave drag at the time of hydroplaning and can improve propulsion performance of the vehicle body. An amphibious vehicle according to the present invention includes a vehicle body capable of moving on water and on land, a front flap with a rear end being fixed to a lower end of the vehicle body, a rear flap with a front end being fixed to a rear part of the vehicle body, and a pair of keels provided along a travel device provided on both sides of the vehicle body on a bottom surface of the vehicle body.

An amphibious vehicle, which enables wave making resistance upon traveling on water to be reduced and propulsive performance of its vehicle main body to be improved, is to be provided. An amphibious vehicle of the present invention includes: a vehicle main body that is movable on water and on land; a rear portion flap having a front end portion fixed to a rear portion of the vehicle main body; and end plates respectively provided at both side end portions of the rear portion flap.

To enlarge a collapsible flap and store the collapsible flap appropriately. In an amphibious vehicle (1) in which a flap (13) which receives lift from water in water navigation is provided to be deployable and storable at a front side in a travel direction of a vehicle body (11), the flap (13) includes a lower flap (21) which is stored to come close to a front surface (11a) of the vehicle body (11) and an upper flap (22) which is stored to come close to an upper surface (11b) of the vehicle body (11), and at least one of the lower flap (21) and the upper flap (22) includes a first flap member (31) and a second flap member (32) and is configured such that a flap length (L.sub.13) in a direction orthogonal to a vehicle width direction is variable.

This amphibious vehicle is provided with a body (11), a traveling device (12) that causes the body (11) to travel on land, a sailing device (13) that causes the body (11) to sail on water, a front flap (31) of which the distal end is inclined upward and the proximal end is rotatably supported by a horizontal shaft (34) on the front end of the body (11), a hydraulic damper (32) serving as a damping member that damps displacement of the front flap (31) relative to the body (11), and a compression coil spring (33) serving as a restoring member that restores the position of the front flap (31) relative to the body (11).

To enlarge a collapsible flap and store the collapsible flap appropriately. In an amphibious vehicle (1) in which a flap (13) which receives lift from water in water navigation is provided to be deployable and storable at a front side in a travel direction of a vehicle body (11), the flap (13) includes a lower flap (21) which is stored to come close to a front surface (11a) of the vehicle body (11) and an upper flap (22) which is stored to come close to an upper surface (11b) of the vehicle body (11), and at least one of the lower flap (21) and the upper flap (22) includes a first flap member (31) and a second flap member (32) and is configured such that a flap length (L.sub.13) in a direction orthogonal to a vehicle width direction is variable.

An amphibious vehicle includes a vehicle body; a flap supported at a lower portion in a traveling direction of the vehicle body to be able to swing in a direction in which an upper edge portion approaches and separates from the vehicle body; a support column which has a fluid actuator capable of expanding and contracting in accordance with a pressure of a working fluid to a cylinder chamber, is connected to the flap in at least a first end portion in a longitudinal direction, and performs adjustment of a swinging angle of the flap by expansion and contraction of the fluid actuator; a power source which supplies the working fluid to the cylinder chamber; and a safety valve which communicates with the cylinder chamber, and opens when an internal pressure of the cylinder chamber becomes greater than a predetermined pressure to discharge the working fluid in the cylinder chamber.

An amphibious vehicle, which enables wave making resistance upon traveling on water to be reduced and propulsive performance of its vehicle main body to be improved, is to be provided. An amphibious vehicle of the present invention includes: a vehicle main body that is movable on water and on land; a rear portion flap having a front end portion fixed to a rear portion of the vehicle main body; and end plates respectively provided at both side end portions of the rear portion flap.

This amphibious vehicle is provided with a body (11), a traveling device (12) that causes the body (11) to travel on land, a sailing device (13) that causes the body (11) to sail on water, a front flap (31) of which the distal end is inclined upward and the proximal end is rotatably supported by a horizontal shaft (34) on the front end of the body (11), a hydraulic damper (32) serving as a damping member that damps displacement of the front flap (31) relative to the body (11), and a compression coil spring (33) serving as a restoring member that restores the position of the front flap (31) relative to the body (11).

A rear flap configuration for an amphibious vehicle includes a vehicle body, a pair of crawlers disposed on both right and left sides with respect to a traveling direction of the vehicle body, and a rear flap connected to a rear part of the vehicle body. The vehicle body has a rear surface including a departure angle surface which extends obliquely upward from a lower edge of the rear surface as the vehicle body extends rearward. The crawlers have upper surfaces positioned above the lower edge, lower surfaces positioned below the lower edge, and rear edges projecting rearward from the lower edge. The rear flap includes a flap body part having a facing edge which faces the lower edge between the crawlers and is vertically rotatably connected to the vehicle body so as to allow the facing edge to come into contact or close proximity with the lower edge.

An amphibious vehicle that can reduce wave drag at the time of hydroplaning and can improve propulsion performance of the vehicle body. The amphibious vehicle includes a vehicle body capable of moving on water and on land, a front flap with a rear end being fixed to a lower end of the vehicle body, a rear flap with a front end being fixed to a rear part of the vehicle body, and a pair of keels provided along a travel device provided on both sides of the vehicle body on a bottom surface of the vehicle body.