Inertia test apparatus for model ship

The present invention provides an inertia test apparatus for a model ship that mimics a pitching inertia radius of an actual ship by reciprocating a model ship. The apparatus includes a base frame providing a supporting force, vertical frames integrally fixed at both sides of the base frame and having a hinge shaft on an upper end, a swing including a pair of fixing members rotatably hung on the hinge shafts of the vertical frames and a bed integrally formed at a lower ends of the fixing members, and providing a pitching inertia radius of the model ship by reciprocating about the hinge shafts, with the model ship seated on the bed, and a centering adjuster seating the model ship on the bed of the swing and matching a center of gravity of the model ship with a center of the swing by allowing the model ship to move.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Korean Patent Application No. KR 2014-0161030 filed on Nov. 18, 2014 and all the benefits accruing therefrom under 35 U.S.C. §119, the contents of which are incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an inertia test apparatus for a model ship and, more particularly, to an inertia test apparatus for a model ship that can mimic an inertial radius of an actual ship by testing a pitching inertial radius of a model ship for dynamic similitude with an actual ship.

Description of the Related Art

In general, fluidic performance of ocean objects such as a ship and a submarine under various situations are examined by performing performance tests at test facilities, such as a towing tank, on scale models having the same shapes as actual vessels.

An inertial test, one of various performance tests performed on models, is a test for mimicking a pitching inertia radius of an actual ship.

Such an inertia test has been performed by a test apparatus of the related art shown inFIG. 1.

The inertia test apparatus includes a baser frame5providing a supporting force and a swing6hung on the base frame5to reciprocally swing.

A model ship is placed on the swing6of the inertia test apparatus by equipment such as forklift or a crane and then a pitching inertia test is performed with the swing6reciprocating.

In the pitching inertia test, an exact test result can be achieved only when the center of gravity of model ship is matched with the center of the swing.

However, a model ship cannot be moved, after being placed on the swing of the inertia test apparatus of the related art.

Accordingly, when using the inertia test apparatus, it is required to check the center of gravity after placing a model ship on the swing, and then repeatedly check the center of gravity while lifting and moving the model ship with a forklift or a crane, so it is very inconvenient and time-consuming.

Further, since support bar7is disposed over the swing in the inertia test apparatus of the related art, a model ship cannot be vertically placed on the swing6from above, but is required to be paced horizontally from a side of the swing6.

Therefore, a model ship cannot be placed in the inertia test apparatus of the related art by a crane, but has to be placed on the swing6only by a forklift.

PRIOR ART DOCUMENT

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made keeping in mind the above problems occurring in the related art, and the present invention is intended to propose an inertia test apparatus for a model ship that can easily match the center of gravity of a model ship with the center of a swing by making the model ship movable on the swing even without lifting the model ship with equipment such as a forklift or a crane.

Further, the preset invention provides an inertia test apparatus for a model ship that can place a model ship on a swing from above, using various types of equipment such as a crane in addition to a forklift, because the area above the swing is open.

In order to achieve the above object, according to one aspect of the present invention, there is provided an inertia test apparatus for a model ship that mimics a pitching inertia radius of an actual ship by reciprocating a model ship. The apparatus includes: a base frame providing a supporting force; vertical frames integrally fixed at both sides of the base frame and having a hinge shaft on an upper end; a swing including a pair of fixing members rotatably hung on the hinge shafts of the vertical frames and a bed integrally formed at a lower ends of the fixing members, and providing a pitching inertia radius of the model ship by reciprocating about the hinge shafts, with the model ship seated on the bed; and a centering adjuster seating the model ship on the bed of the swing and matching a center of gravity of the model ship with a center of the swing by allowing the model ship to move.

The centering adjuster may include: a lifting frame vertically movably disposed in a chamber formed in the shape of a groove at a center of the swing, supporting the model ship when protruding over the bed, and placing the model ship on the bed when moving down under the bed; rollers rotatably coupled to the lifting frame, supporting the model ship in a movable state in close contact with the model ship when the lifting frame is moved up, and being separated from the model ship when the lifting frame is moved down; and a lifting mechanism disposed in the chamber of the bed and moving up and down the lifting frame.

The lifting mechanism may include: a rotary shaft disposed under the lifting frame, providing torque, and having a thread longitudinally formed; a movable shaft having a first end thread-fastened to the rotary shaft and a second end extending perpendicular to the rotary shaft, and moving in a longitudinal direction of the rotary shaft when the rotary shaft is rotated; and lifting links coupled to the second end of the movable shaft, supporting the lifting frame, with both ends rotatably coupled to the lifting frame and the chamber of the bed, and moving up or down the lifting frame by opening or closing when the movable shaft is moved.

The lifting link may include: a first link arm having a first end rotatably coupled to a hinge shaft on the lifting frame and a second end rotatably coupled to the movable shaft; and a second link arm having a first end rotatably coupled to a hinge shaft on the chamber of the bed and a second end coupled to the movable shaft to be rotated with the first link arm.

The second ends of the first link arm and the second link arm may extend away from the hinge shafts toward the chamber of the bed and the lifting frame, respectively, and the lifting links may further include support rollers rotatably coupled to the second ends of the first link arm and the second link arm and supporting the chamber of the bed and the lifting frame, respectively.

According to the inertia test apparatus for a model ship of the present invention, since rollers are disposed at the lifting frame of the centering adjuster, a model ship can be moved with the lifting frame lifted and the center of gravity of a model ship can be matched with the center of the swing, so the time taken to prepare a test can be considerably reduced.

Further, according to the present invention, since the lifting mechanism of the centering adjuster moves the movable shaft when the rotary shaft is rotated, the lifting frame is moved up or down by the lifting links that are opened or closed, so the lifting frame can be stably moved up and down.

Further, according to the present invention, since the lifting links have the extending link arms and the support rollers are disposed at the extending ends and support the lifting frame and the chamber of the bed, the lifting frame can more firmly support a model ship while it is lifted up.

Further, according to the present invention, since the fixing members of the swing are rotatably coupled to hinge shafts on a pair of vertical frames and the area over the swing is open, it is possible to mount a model ship from above the swing with various types of equipment.

DETAILED DESCRIPTION OF THE INVENTION

Exemplary embodiments of the present invention will be described more fully hereinafter with reference to the accompanying drawings. In the following description of the present invention, detailed descriptions of known functions and components incorporated herein will be omitted.

Reference will now be made in detail to various embodiments of the present invention, specific examples of which are illustrated in the accompanying drawings and described below, since the embodiments of the present invention can be variously modified in many different forms. While the present invention will be described in conjunction with exemplary embodiments thereof, it is to be understood that the present description is not intended to limit the present invention to those exemplary embodiments. On the contrary, the present invention is intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments that may be included within the spirit and scope of the present invention as defined by the appended claims.

An inertia test apparatus for a model ship according to the present invention may include, as shown inFIG. 2, a base frame100, vertical frames200, a swing300, and a centering adjuster400.

The support frame100is a member for providing a supporting force.

The base frame100may be fixed on the ground, or may be movable using a moving member such as casters (not shown) on the bottom.

The vertical frames200integrally and vertically fixed at both sides of the base frame100, as shown inFIG. 2, so they function as pillars supporting the swing300, which will be described below.

A hinge shaft210is disposed at the tops of the vertical frames200and supports the swing300, as shown inFIG. 2, so the swing300can reciprocate.

The swing300is held on the hinge shafts210of the vertical frames200to be able to swing, so it provides a pitching inertia radius of a model ship while reciprocating the model ship.

The swing300, as shown inFIG. 2, includes a pair of fixing members310having an upper end rotatably coupled to the hinge shafts210of the vertical frames200and a bed320integrally formed at the lower ends of the fixing members310to seat a model ship.

That is, while the swing300repeatedly swings about the hinge shafts210of the vertical frame200, with the model ship on the bed320, the pitching inertia radius of the model ship is tested.

Since the hinge shafts210where the vertical members310are coupled are separately disposed on the vertical frames200, the area above the swing300is open, so a model ship can be placed on the bed320from above by various types of equipment such as a crane or a forklift.

The centering adjuster400is provided to seat a model ship on the bed320of the swing300and easily move the center of gravity of the model ship to the center of the swing300.

The centering adjuster400, for example, may include a lifting frame410, a roller420, and a lifting assembly430, as shown inFIG. 3.

The lifting frame410is coupled to the bed320of the swing300, and supports a model ship by moving up or seats a model ship onto the bed320by moving down.

The lifting frame410, as shown inFIGS. 3 and 4, is disposed in a chamber320aformed like a groove at the center of the bed320and can be moved up/down therein by the lifting assembly430, which will be described below.

The rollers420are rotatably coupled to the lifting frame410, as shown inFIGS. 3 and 4, in order that the center of gravity of a model ship can be adjusted by movably supporting the model ship to allow the model ship to move.

That is, as shown inFIG. 5, as the lifting frame410is moved up over the bed320, the rollers420movably support a model ship. Further, when the lifting frame410is moved down into the chamber320a, as shown inFIG. 4, the rollers420are separated from a model ship and the model ship is seated on the bed320.

The lifting assembly430, as shown inFIG. 3, is disposed in the chamber320aof the bed320and moves up/down the lifting frame410.

The lifting assembly430, as shown inFIG. 3, for example may include a rotary shaft431, a movable shaft432, and lifting links433.

The rotary shaft431, a member providing torque by being rotated by a user, as shown inFIG. 3, is disposed under the lifting frame410in the chamber320aand has a thread that is longitudinally formed.

The movable shaft432is moved in the longitudinal direction of the rotary shaft431, when the rotary shaft431is rotated.

The movable shaft432, as shown inFIGS. 3 and 4, has a first end thread-fastened to the rotary shaft431through a female threaded-portion432aand a second end extending perpendicular to the rotary shaft431out of the lifting frame410.

The lifting link433that will be described below is fixed to the second end of the movable shaft432to prevent rotation, so when the rotary shaft431is rotated, the female threaded-portion432ais horizontally moved in the longitudinal direction of the rotary shaft431, thereby operating the lifting link433.

The lifting link433, as shown inFIG. 3, is coupled to the second end of the movable shaft432and can be opened/closed and both ends are rotatably coupled to the lifting frame410and the chamber320aof the bed320, so when the movable shaft432is horizontally moved, the lifting link433supporting the lifting frame410is opened or closed to lift the lifting frame410, as shown inFIGS. 4 and 5.

In detail, the lifting link433, as shown inFIGS. 3 and 4, is composed of a first link arm433aand a second link arm44bcoupled to each other to be opened/closed and movably coupled to the movable shaft432. An end of the first link arm433ais rotatably coupled to a hinge shaft H of the lifting frame410and an end of the second link arm433bis rotatably coupled to a hinge shaft H of the chamber320a, thereby supporting the lifting frame410.

Accordingly, when the lifting shaft432is moved forward by forward rotation of the rotary shaft431, the first link arm433aand the second link arm433bof the lifting link433are opened and lift the lifting frame410, as shown inFIG. 5.

Further, when the lifting shaft432is moved backward by backward rotation of the rotary shaft431, the first link arm433aand the second link arm433bof the lifting link433are closed and move the lifting frame410down, as shown inFIG. 4.

In the lifting link433, the ends of the first link arm433aand the second link arm433bcan make an X-shape by extending toward the chamber320aand the lifting frame410, respectively, as shown inFIG. 6, and support rollers433care rotatably disposed at the extending ends, so the chamber320aand the lifting frame410can be more firmly supported.

Operation of the present invention including the components described above will now be described.

In order to perform an inertia test on a model ship, a tester lifts and places a model ship on the bed of the swing300, using equipment such as a crane or a forklift.

Further, after separating the equipment from the model ship, the tester checks whether the center of gravity of the model ship and the center of the swing300are matched. When the center of gravity of the model ship and the center of the swing300are not matched, the tester matches the centers by moving the model ship after lifting the lifting frame410and the rollers420by rotating the rotary shaft431forward.

As the lifting shaft432is moved forward and presses the lifting links433by forward rotation of the rotary shaft421, as shown inFIG. 5, the lifting frame410and the rollers420are lifted by the lifting links433that are opened, so the lifting frame410and the rollers420movably support the model ship at the positions and allow the center of gravity of the model ship to be moved.

After matching the center of gravity of the model ship with the center of the swing, the tester moves the lifting frame410and the rollers420down and places the model ship on the bed320by rotating the rotary shaft431backward.

As the lifting shaft432is moved backward and presses the lifting links433by backward rotation of the rotary shaft421, as shown inFIG. 4, the lifting frame410and the rollers420are moved down by the lifting links433that are closed, so the lifting frame410and the rollers420are moved down into the chamber320aand separated from the model ship, and accordingly the model ship is left on the bed320.

As described above, according to the inertia test apparatus for a model ship of the present invention, since the rollers420are disposed on the lifting frame410of the centering adjuster400, a model ship can be moved when the lifting frame410is raised, so it is possible to easily match the center of gravity of a model ship with the center of the swing300, and accordingly, the time taken to prepare the test can be considerably reduced.

Further, according to the present invention, since the lifting mechanism430of the centering adjuster400moves the movable shaft432when the rotary shaft431is rotated and the lifting links433lift the lifting frame410by opening or closing, the lifting frame410can be stably lifted.

Further, according to the present invention, since the link arms433aand433bof the lifting link433extend and the support rollers433bare disposed at the extending end and can support the lifting frame410and the chamber320aof the bed320, the lifting frame410can move up while more firmly supporting a model ship.

Further, according to the present invention, since the fixing members310of the swing300are rotatably coupled to the hinge shafts210disposed on a pair of vertical frames200, the area over the swing300is open, thus it is possible to mount a model ship on the swing300from above using various types of equipment.

The present invention was described with reference to the exemplary embodiments, but those are provided only for explanation and are not intended to limit the scope of the present invention. It will be understood to those skilled in the art that the present invention may be replaced, changed, and modified in various ways without departing from the spirit of the present invention.