Link mechanism for vehicle door and vehicle door opening and closing apparatus having the same

1. A link mechanism for a vehicle door, comprising:

a body including a first end portion facing a vehicle body and a second end portion facing a vehicle door;

a first mounting member mounted on the vehicle body, and rotatably connected to the first end portion of the body through a first shaft;

a second mounting member mounted on the vehicle door, and rotatably connected to the second end portion of the body through a second shaft; and

a rotation restricting unit configured to selectively restrict a rotation of the second mounting member;

wherein the rotation restricting unit includes a restricting element that releasably holds the second mounting member, and

wherein the restricting element moves between an engaging position in which the restricting element directly contacts the second mounting member and a release position in which the restricting element releases the second mounting member.

2. The link mechanism according to claim 1 , wherein the restricting element is pivotally mounted on the body by a pivot pin, and the restricting element is biased toward the engaging position by a torsional biasing element.

3. The link mechanism according to claim 2 , wherein the second mounting member includes a plurality of recesses, and the restricting element includes a plurality of projections releasably fitted into the plurality of recesses.

4. The link mechanism according to claim 1 , wherein the body further includes a first damper and a second damper which are spaced apart from each other to restrict a range of rotation of the second mounting member.

5. The link mechanism according to claim 1 , wherein the restricting element is slidably mounted on the body to advance toward the second mounting member or be reversed from the second mounting member, and the restricting element is biased toward the engaging position by a longitudinal biasing element.

6. A vehicle door opening and closing apparatus, comprising:

a vehicle door;

a rail mounted on a vehicle body; and

a link mechanism that connects the vehicle body and the vehicle door, and allows the vehicle door to open and close in one mode selected from sliding mode, in which the vehicle door slides along the rail, and swing mode, in which the vehicle door swings in a predetermined position of the rail,

wherein the link mechanism includes:

a body having a first end portion facing the vehicle body and a second end portion facing the vehicle door;

a first mounting member moving along the rail of the vehicle body, and rotatably connected to the first end portion of the body through a first shaft;

a second mounting member mounted on the vehicle door, and rotatably connected to the second end portion of the body through a second shaft; and

a rotation restricting unit configured to selectively restrict a rotation of the second mounting member,

wherein the rotation restricting unit includes a restricting element that releasably holds the second mounting member, and

wherein the restricting element moves between an engaging position in which the restricting element directly contacts the second mounting member and a release position in which the restricting element releases the second mounting member.

7. The vehicle door opening and closing apparatus according to claim 6 , wherein:

the link mechanism has a rotation axis and includes a hold lock,

the link mechanism is releasably held in the predetermined position of the rail by the hold lock,

the vehicle door swings around the rotation axis when the link mechanism is held in the predetermined position of the rail by the hold lock, and

the vehicle door slides along the rail when the link mechanism is released by the hold lock.

8. The vehicle door opening and closing apparatus according to claim 7 , wherein the rotation axis is defined by the second shaft.

9. The vehicle door opening and closing apparatus according to claim 7 , wherein the hold lock is mounted on the body of the link mechanism.

10. The vehicle door opening and closing apparatus according to claim 6 , wherein the first mounting member is movably mounted on the vehicle body through rollers, the rollers are rotatably mounted on the first mounting member, and the rollers roll along the rail.

11. The vehicle door opening and closing apparatus according to claim 6 , wherein the body has a pivot lug that protrudes from the first end portion toward the first mounting member, and the pivot lug is connected to the first mounting member through the first shaft.

12. The vehicle door opening and closing apparatus according to claim 6 , wherein the first end portion of the body includes a first restricting surface and a second restricting surface which restrict a range of rotation of the first mounting member, and the first restricting surface and the second restricting surface intersect at a predetermined angle.