Convertible tandem stroller with a double seat transfer mechanism

1. A convertible tandem stroller with a double seat transfer mechanism, comprising:

a wheeled rack;

swivel mount, mounted on the wheeled rack including a fixed portion, and a swivable portion pivoted on said fixed portion through a shaft;

a pair of extension arms, connected with the swivable portion and capable of swiveling relative to the fixed portion and the wheeled rack;

a driving element connected with the swivable portion; and

a pair of chairs swivelly mounted on the pair of extension arms, each having a driven element and linking element; the two linking elements associated the driving element and the two driven elements;

when the pair of extension arms is swiveling relative to the fixed portion, the driving element follows the swivable portion to rotate and drive the two driven elements via the two linking elements, thereby driving the pair of chairs to change direction simultaneously.

2. The convertible tandem stroller with a double seat transfer mechanism of claim 1 , wherein each of the chairs has a vertical shaft for pivoting on the extension arms, and always capable of self-keeping in a forward oriented position when the pair of extension arms is swiveling relative to the fixed portion.

3. The convertible tandem stroller with a double seat transfer mechanism of claim 1 , wherein each of the chairs includes a body frame and a spring-biased latch, the body frame is rotatable relative to the driven element, and the spring-biased latch is operatively mounted between the body frame and the driven element and capable of releasably locking the body frame to the driven element.

4. The convertible tandem stroller with a double seat transfer mechanism of claim 1 , wherein the wheeled rack has a push arm extending rearward and upwardly, and includes at least a front strut and a pair of rear struts both are firmly connected to the swivel mount; and

wherein the front strut and the rear struts connect at least a front wheel and two rear wheels under the wheeled rack.

5. The convertible tandem stroller with a double seat transfer mechanism of claim 4 , wherein the driving element is symmetrically formed with two cam slots for slidably engaging and guiding the linking elements to move along the guiding slots back and forth thereby increasing a distance between the chairs when the pair of extension arms is swiveling from the transversely oriented position to the longitudinally oriented position.

6. The convertible tandem stroller with a double seat transfer mechanism of claim 1 , wherein the pair of extension arms is capable of swiveling relative the wheeled rack and positioning on a longitudinally oriented position and a transversely oriented position so as to convert the stroller from a tandem style to a side-by-side double seat style, and vice versa.

7. The convertible tandem stroller with a double seat transfer mechanism of claim 6 , wherein each of the chairs has a vertical shaft for pivoting on the extension arms, and always capable of self-keeping in a forward oriented position when the pair of extension arms is swiveling between the longitudinally oriented position and a transversely oriented position.

8. The convertible tandem stroller with a double seat transfer mechanism of claim 7 further includes a spring-biased latch operatively mounted between the fixed portion and the swivable portion for selectively positioning the extension arms on the longitudinally oriented position and the transversely oriented position.

9. The convertible tandem stroller with a double seat transfer mechanism of claim 7 , wherein when the pair of extension arms is swiveling from the longitudinally oriented position to the transversely oriented position, the chairs are swiveling to a forward oriented position simultaneously.

10. The convertible tandem stroller with a double seat transfer mechanism of claim 7 , wherein when the pair of extension arms is swiveling from the transversely oriented position to the longitudinally oriented position, the chairs are swiveling to a forward oriented position simultaneously.

11. The convertible tandem stroller with a double seat transfer mechanism of claim 6 , wherein the fixed portion is symmetrically formed with two guiding slots for guiding the linking elements to a distance between the driven elements for permitting the pair of chairs to close to each other while the pair of extension arms is swiveling to the transversely oriented position and concerting the stroller to the side-by-side double seat style.

12. The convertible tandem stroller with a double seat transfer mechanism of claim 11 , wherein the driving element is symmetrically formed with two cam slots for slidably engaging and guiding the linking elements to move along the guiding slots back and forth thereby decreasing a distance between the chairs when the pair of extension arms is swiveling from the longitudinally oriented position to the transversely oriented position.