Infant carrier apparatus having multiple configurations of use and its operating method

1. An infant carrier apparatus comprising:

a seat assembly;

a backrest assembly, including a first and second backrest frame, wherein the first backrest frame includes at least one first side segment and a first transverse segment, the second backrest frame includes at least one second side segment and a second transverse segment, the first side segment being coupled with the seat assembly via a first pivot point; and

a backrest holding mechanism movably assembled between the first and second transverse segment, wherein the backrest holding mechanism includes a latch element movable between a first and second position;

wherein the first position of the latch element causes the backrest holding mechanism to be in locking engagement with the first transverse segment to prevent rotation of the backrest assembly relative to the seat assembly, and the second position of the latch element removes the locking engagement of the backrest holding mechanism with the first transverse segment to permit rotation of the backrest assembly relative to the seat assembly.

2. The apparatus according to claim 1 , wherein the backrest holding mechanism further includes a link element that is respectively connected pivotally with the first and second transverse segments, the latch element being movably assembled with the link element.

3. The apparatus according to claim 2 , wherein the link element is pivotally connected with the first transverse segment about a first pivot axis, and pivotally connected with the second transverse segment about a second pivot axis parallel to the first pivot axis.

4. The apparatus according to claim 2 , wherein the second side segment is coupled with the seat assembly at a second pivot point.

5. The apparatus according to claim 4 , wherein the second pivot point is located above the first pivot point.

6. The apparatus according to claim 4 , wherein the first and second backrest frames are movable in unison owing to the movable connection of the link element, when the latch element is kept at the second position.

7. The apparatus according to claim 6 , wherein the link element respectively rotates relative to the first and second transverse segments when the first and second backrest frames respectively rotate about the first and second pivot points.

8. The apparatus according to claim 1 , wherein the first transverse segment includes a latch-engaging portion, the latch element when at the first position being in locking engagement with the latch-engaging portion.

9. The apparatus according to claim 8 , wherein the latch-engaging portion includes a plurality of radial grooves, and the latch element is operable to engage with different radial grooves according to different angular positions of the backrest assembly relative to the seat assembly.

10. The apparatus according to claim 8 , wherein the latch-engaging portion is changed in position relative to the seat assembly as the first backrest frame rotates.

11. The apparatus according to claim 8 , wherein the backrest holding mechanism further includes at least a spring adapted to bias the latch element toward the first position into locking engagement with the latch-engaging portion.

12. The apparatus according to claim 11 , wherein the backrest holding mechanism further includes a release button that is operable to cause the latch element to move toward the second position.

13. A method of operating an infant carrier apparatus, wherein the infant carrier apparatus includes a seat assembly and a backrest assembly, the backrest assembly including a first and second backrest frame, the first backrest frame having a first side segment coupled with the seat assembly at a first pivot point, the method comprising:

providing a backrest holding mechanism at a transverse portion of the backrest assembly, wherein the backrest holding mechanism is movably connected with a first transverse segment of the first backrest frame and a second transverse segment of the second backrest frame;

switching the backrest holding mechanism from a locked state to an unlocked state, wherein the first backrest frame is allowed to rotate relative to the backrest holding mechanism in the unlocked state; and

rotating the backrest assembly relative to the seat assembly.

14. The method according to claim 13 , wherein the backrest holding mechanism includes a link element that is respectively connected pivotally with the first and second transverse segment, and a latch element assembled with the link element, wherein the link element is locked with the first transverse segment via a locking engagement of the latch element.

15. The method according to claim 14 , wherein the backrest holding mechanism further includes at least a spring adapted to bias the latch element into locking engagement with the first transverse segment.

16. The method according to claim 15 , wherein the backrest holding mechanism further includes a release button, and the step of switching the backrest holding mechanism from a locked state to an unlocked state includes pressing the release button to cause the latch element to move out of the locking engagement with the first transverse segment.

17. The method according to claim 13 , wherein the second backrest frame includes a second side segment that is coupled with the seat assembly at a second pivot point, and the first and second backrest frames rotate in unison relative to the seat assembly via the movable connection of the backrest holding mechanism.