Foldable display device

1. A foldable display device, comprising:

a first body and a second body formed in a plate shape to be arranged symmetrically;

a display part attached to the first body and the second body to be folded or unfolded; and

a hinge device coupled to the first body and the second body to connect the bodies to each other and allowing the first body and the second body to be folded and unfolded,

wherein the hinge device includes:

a first bracket coupled to the first body and a second bracket coupled to the second body;

first and second main shafts passing through one end of the first and second brackets and disposed in parallel respectively;

a rotation inducing part fitted to outer surfaces of the first and second main shafts to guide linear motion when the first and second main shafts rotate; and

a mobile part composed of first and second link connectors fitted to outer surfaces of the first and second main shafts and connected to the rotating induction unit, first and second links hinged to the first and second link connectors respectively, and first and second connection plates hinged to the first and second links and attached to the first and second bodies respectively,

in which the first and second bodies are folded, the first and second connection plates are in proximity to each other, and the first and second link connectors move about the first and second main shafts to be in proximity to each other

wherein the rotation inducing part includes:

first and second tubular bodies fitted to outer surfaces of the first and second main shafts and having guide grooves formed in a diagonal direction respectively;

first and second shaft pins formed on the first and second main shafts respectively;

a connecting rod connected across one end portions of the first and second tubular bodies; and

an additional bracket connecting middle parts of the first and second tubular bodies and having a fastening hole,

wherein the first and second shaft pins are coupled to the guide grooves of the first and second tubular bodies, respectively,

wherein the foldable display device further comprising:

first and second springs coupled to the first and second shaft pins respectively; and

a support to which the first and second brackets are coupled;

wherein each of the first and second springs are supported in close contact with the support at one end thereof, and in close contact with a gear coupling part at the other end thereof,

wherein the gear coupling part includes:

a first support plate supporting the first and second springs and coupled to the first and second shaft pins;

a second support plate coupled in parallel with the first support plate and coupled to the first and second shaft pins;

first and second gears interposed between the first and second support plates and coupled to the first and second shaft pins respectively; and

multiple interlocking gears gear-engaged to the first and second gears,

wherein each of the first and second bodies is formed with a slide groove into which each of the first and second bracket is slidably coupled;

a slide protrusion is formed in the slide groove; and

each of the first and second brackets is formed with a rail groove into which the slide protrusion is fitted.

2. The device of claim 1 , wherein the hinge device is provided so that the rotation inducing part is coupled to the inside of the first and second link connectors to be freely rotated.

3. The device of claim 1 , wherein the first and second connection plates have first and second links connected at both sides thereof and are equipped with first connection ring and second connection ring, respectively, and

the first and second links are hinged to the first and second link connectors and hinged to the first and second connection plates, respectively.

4. The device of claim 3 , wherein the first connection ring is formed with a coupling hole into which the first main shaft is fitted, and formed with a guide pin coupled to a long hole of the movement guide; and

the second connection ring is formed with a coupling hole into which the second main shaft is fitted, and formed with a guide pin coupled to a long hole of the movement guide.

5. The device of claim 1 , wherein the rotation inducing part is formed with an accommodating portion on a top surface of the connecting rod, so that a recessed arc-shaped portion of the display part is inserted into the accommodating portion.

6. The device of claim 3 , further comprising:

a support to which the first and second main shafts are coupled and by which first and second springs are supported, wherein the support is formed with an accommodating portion on a top portion thereof so that an arc-shaped portion is inserted when the display part is folded.