Stroller having front wheels that can be turned stably and smoothly

A stroller, comprising a main frame, a linkage, and a support unit, wherein:

• the main frame has two bottom rails and two front wheels;
• the linkage includes two shaft seats, two mounting sleeves, an elbow, two mounting rings, two connecting tubes, two wheel shafts, and an elastic member;
• each of the shaft seats has a first end formed with two support plates and a receiving space located between the two support plates, and a second end formed with a barrel having an inside formed with a through hole, the barrel has a periphery formed with a recess communicating with the through hole;
• each of the mounting sleeves is pivotally mounted on a respective one of the shaft seats and has a first end formed with a pivot portion pivotally mounted in the receiving space between the support plates of the respective shaft seat and a second end formed with a mounting portion;
• the elbow is mounted between the mounting sleeves;
• each of the mounting rings is mounted in the recess of the barrel of a respective one of the two shaft seats and has an inner wall formed with a through bore aligning with the through hole of the barrel and a protruding locking block extended radially inward from the through bore;
• each of the connecting tubes is mounted in the through hole of the barrel of a respective one of the shaft seats and extended through the through bore of a respective one of the mounting rings;
• each of the wheel shafts is extended through a respective one of the front wheels and detachably locked in a respective one of the connecting tubes;
• the elastic member is urged between the shaft seats;
• the support unit is mounted on the linkage and includes two joints, a main bracket, a cover, a support bracket, a mounting tube, an inner tube, and two connecting seats;
• each of the joints has a first side formed with a base pivotally mounted on a respective one of the shaft seats and a second side formed with a socket;
• the main bracket is mounted between the joints;
• the cover is mounted on the main bracket;
• the support bracket is mounted on the main bracket and has a lower portion formed with two opposite support plates each formed with a first hole and a second hole;
• the mounting tube is mounted between the support plates of the support bracket and is aligned with the second hole of each of the support plates;
• the inner tube is mounted in the mounting tube and has two ends protruding from the support plates of the support bracket;
• each of the connecting seats is mounted between the support bracket and a respective one of the bottom rails of the main frame and includes a first sleeve mounted on a respective end of the inner tube and a second sleeve mounted on a front end of a respective one of the bottom rails.