3c, and the lateral roller 11 and the longitudinal roller 12 supported by the bracket 9.

The bracket 9 includes a fixed portion 9a attached to the first arm 3, and a base portion 9b formed integrally with the fixed portion 9a. The fixed portion 9a is formed in a C shape to overlap the upper portion of the first upper lateral wall 3b and the lower portion of the first lower lateral wall 3c. The fixed portion 9a is rotatably supported by the first arm 3 via a support shaft 13. The support shaft 13 passes through the first upper lateral wall 3b and the first lower lateral wall 3c and extends in the upward/downward direction.

The base portion 9b extends from the lower wall of the fixed portion 9a toward the lower rail 105. The lateral roller 11 and the longitudinal roller 12 are supported by an end portion of the base portion 9b on the side of the lower rail 105.

The lateral roller 11 includes a spindle 11a protruding from the base portion 9b toward the passenger compartment side in the vehicle width direction, and a lateral roller main body 11b rotatably supported by an end portion of the spindle 11a on the passenger compartment side. The lateral roller main body 11b is received in the lateral roller receiving portion 5a of the first rail 5.

Two longitudinal rollers 12 are provided. The two longitudinal rollers 12 are disposed on both sides in the forward/rearward direction with the lateral roller 11 sandwiched therebetween. The longitudinal roller 12 includes a spindle 12a protruding upward from the base portion 9b, and a longitudinal roller main body 12b rotatably supported by an upper end of the spindle 12a. The spindle 12a and the longitudinal roller main body 12b are aligned with the lateral roller main body 11b in the upward/downward direction. The longitudinal roller main body 12b is received in the longitudinal roller receiving portion 5b. Since the roller main bodies 11b and 12b are rotated in the roller receiving portions 5a and 5b, respectively, the vehicle body-side roller unit 8 is slidably provided on the first rail 5.

The vehicle body-side roller 14 (driven vehicle body-side guide) is provided on a side of the first arm 3 closer to the door rail 2 than the vehicle body-side roller unit 8. The vehicle body-side roller 14 is disposed on the first upper lateral wall 3b of the first arm 3. The vehicle body-side roller 14 includes a spindle 14a protruding upward from the first upper lateral wall 3b, and a vehicle body-side roller main body 14b rotatably supported by the upper end of the spindle 14a.

A place of the first upper lateral wall 3b corresponding to the vehicle body-side roller 14 slightly overhangs toward a side opposite to the first longitudinal wall 3a. The vehicle body-side roller main body 14b is received in the second rail 6. Since the vehicle body-side roller main body 14b is rotated in the second rail 6, the vehicle body-side roller 14 is slidably provided on the second rail 6.

The door-side roller 15 is provided on an end portion of the first arm 3 on the side of the door rail 2. The door-side roller 15 is disposed on the first upper lateral wall 3b of the first arm 3. The door-side roller 15 includes a spindle 15a protruding upward from the first upper lateral wall 3b, and a door-side roller main body 15b rotatably supported on the upper end of the spindle 15a. The door-side roller main body 15b is received in the door rail 2. Since the door-side roller main body 15b is rotated in the door rail 2, the door-side roller 15 is slidably provided on the door rail 2.

As shown in FIG. 5 in detail, a cross-sectional shape of the second arm 4 in the vehicle width direction and the upward/downward direction is a C shape, a passenger compartment side of which is open. That is, the second arm 4 has a second longitudinal wall 4a in the upward/downward direction, a second upper lateral wall 4b protruding from an upper end of the second longitudinal wall 4a toward the passenger compartment side, and a second lower lateral wall 4c protruding from a lower end of the second longitudinal wall 4a toward the passenger compartment side, which are formed integrally with each other.

A width between an inner surface of the second upper lateral wall 4b and an inner surface of the second lower lateral wall 4c is slightly greater than a width between an outer surface of the first upper lateral wall 3b and an outer surface of the first lower lateral wall 3c. Tongue portions 16 are formed to extend from the end portions of the second upper lateral wall 4b and the second lower lateral wall 4c on the side of the first arm 3, respectively. Each of the tongue portions 16 extends in a longitudinal direction of the second arm 4. Each of the tongue portions 16 overlaps the outer surface of the first upper lateral wall 3b and overlaps the outer surface of the first lower lateral wall 3c. Each of the tongue portions 16 is rotatably supported by the first arm 3 via a support shaft 17 (arm-side support portion).

The support shaft 17 is provided on a central portion of the first arm 3 in a longitudinal direction. The central portion in the longitudinal direction does not mean only the complete center in the longitudinal direction of the first arm 3, but also includes the surrounding neighborhood including the center. The support shaft 13 passes through the first upper lateral wall 3b and the first lower lateral wall 3c and extends in the upward/downward direction.

An end portion of the second arm 4 on the side of the rear slide door 103b is rotatably supported by the rear slide door 103b via a door-side support portion 18. As shown in FIG. 5 in detail, a cross-sectional shape of the door-side support portion 18 in the vehicle width direction and the upward/downward direction is a C shape, a passenger compartment side of which is open. That is, the door-side support portion 18 has a support portion longitudinal wall 18a extending in the upward/downward direction, a support portion upper lateral wall 18b protruding from the upper end of the support portion longitudinal wall 18a toward the passenger compartment side, and a support portion lower lateral wall 18c protruding from the lower end of the support portion longitudinal wall 18a toward the passenger compartment side, which are formed integrally.

The support portion longitudinal wall 18a is formed long in the forward/rearward direction. A length of the support portion longitudinal wall 18a in the forward/rearward direction is substantially equal to a length of the second arm 4 in the longitudinal direction except the tongue portions 16. The support portion longitudinal wall 18a is placed on the second arm attachment surface 107a of the rear slide door 103b. A length of the second arm attachment surface 107a in the forward/rearward direction is slightly greater than a length of the support portion longitudinal wall 18a in the forward/rearward direction. The support portion longitudinal wall 18a is fastened and fixed to the second arm attachment surface 107a via a bolt 20.

A width between an inner surface of the support portion upper lateral wall 18b and an inner surface of the support portion lower lateral wall 18c is slightly greater than a width between an outer surface of the second upper lateral wall 4b and an outer surface of the second lower lateral wall 4c.

Tongue portions 19 are formed to extend from closed side end portions of the support portion upper lateral wall 18b and the support portion lower lateral wall 18c toward the passenger compartment side, respectively. Each of the tongue portions 19 overlaps the outer surface of the second upper lateral wall 4b and overlaps the outer surface of the second lower lateral wall 4c. The second arm 4 is rotatably supported by each of the tongue portions 19 via a support shaft 21. The support shaft 21 passes through the second upper lateral wall 4b and the second lower lateral wall 4c and extends in the upward/downward direction.

Here, a length of the support portion longitudinal wall 18a in the forward/rearward direction is substantially equal to a length of the second arm 4 in the longitudinal direction except the tongue portions 16, and a length of the second arm attachment surface 107a in the forward/rearward direction is slightly greater than a length of the support portion longitudinal wall 18a in the forward/rearward direction. Accordingly, the second arm attachment surface 107a is formed in a pivoting region of the second arm 4, i.e., a region overlapping the second arm 4 in the vehicle width direction.

Next, an operation of the slide door support mechanism 1 will be described on the basis of FIG. 2 to FIG. 5. As shown in FIG. 2, when the rear slide door 103b is located at the open position, the vehicle body-side roller 14 is located at the second rail main body 6a of the second rail 6. For this reason, the vehicle body-side roller unit 8 and the vehicle body-side roller 14 are disposed at a fixed interval in the vehicle width direction. For this reason, an angle between the first arm 3 and the vehicle body 101 and an angle between the first arm 3 and the rear slide door 103b are large, and the first arm 3 is in an upright state.

In a state in which the first arm 3 stands upright, an angle between the first arm 3 and the second arm 4 and an angle between the second arm 4 and the rear slide door 103b are also large, and the second arm 4 stands also upright following the first arm 3. In addition, in a state in which the first arm 3 stands upright, the door-side roller 15 is located near the closed position (toward the front) of the door rail 2.

When the rear slide door 103b is moved to the closed position from this state, as shown in FIG. 3, the vehicle body-side roller 14 is slid to the curved rail portion 6b. Since the first rail 5 and the curved rail portion 6b gradually approach each other in the vehicle width direction as they move toward the closed position, the vehicle body-side roller 14 is shifted rearward relative to the vehicle body-side roller unit 8.

Accordingly, an angle between the first arm 3 and the vehicle body 101 and an angle between the first arm 3 and the rear slide door 103b are gradually reduced, and the first arm 3 is gradually folded. An angle between the first arm 3 and the second arm 4 and an angle between the second arm 4 and the rear slide door 103b are also reduced, and the second arm 4 is also folded following the first arm 3.

Here, an end portion of the second arm 4 on the side of the first arm 3 is rotatably supported by the first arm 3 via the support shaft 17. An end portion of the second arm 4 on the side of the rear slide door 103b is rotatably supported by the rear slide door 103b via the door-side support portion 18. For this reason, the second arm 4 is folded by pushing the first arm 3 rearward. As a result, the first arm 3 is folded while moving the door-side roller 15 to slide along the door rail 2 in an open position direction (rearward). Then, the rear slide door 103b is pulled toward the passenger compartment side, and the rear slide door 103b is located at the closed position.

In addition, as shown in FIG. 5 in detail, since a width between an inner surface of the second upper lateral wall 4b and an inner surface of the second lower lateral wall 4c is slightly greater than a width between an outer surface of the first upper lateral wall 3b and an outer surface of the first lower lateral wall 3c, when the first arm 3 and the second arm 4 are folded, a part of the first arm 3 is received in the second arm 4. Since a width between an inner surface of the support portion upper lateral wall 18b and an inner surface of the support portion lower lateral wall 18c is slightly greater than a width between an outer surface of the second upper lateral wall 4b and an outer surface of the second lower lateral wall 4c, when the second arm 4 is folded in the door-side support portion 18, the second arm 4 is received in the door-side support portion 18. For this reason, when the first arm 3 or the second arm 4 is folded, the first arm 3 or the second arm 4 is not bulky.

In this way, the slide door support mechanism 1 includes the lower rail 105 provided on the vehicle body 101, the door rail 2 provided on the rear slide door 103b, the first arm 3 that bridges between the lower rail 105 and the door rail 2, the vehicle body-side roller unit 8, the vehicle body-side roller 14 and the door-side roller 15 provided on the first arm 3, and the second arm 4 pivotably supported by the rear slide door 103b and the first arm 3.

For this reason, when the rear door opening portion 102b is closed by the rear slide door 103b, the first arm 3