Foldable Stroller and Frame Assembly

Abstract

A foldable stroller has a frame reconfigurable between an unfolded and a folded configuration. The frame has left and right sides, each having a fold joint, a handle push arm slidably coupled to the fold joint, a front leg substantially parallel to the push arm with an upper end connected to the fold joint, a rear leg pivotably extending down from the fold joint, and a drive link with a rear end pivotally coupled to the rear leg and a front end pivotally coupled to a lower end of the push arm. When moved to the folded configuration, the push arm slides downward relative to the fold joint and the rear leg and the drive link rear end move toward the front leg and push arm. In the folded configuration, the rear leg is substantially parallel with and close to the front leg and push arm. A slide collar can be fixed to the front leg and define an opening. The push arm can slide within the opening. A drive mechanism can be operably coupled to the frame to assist in moving the frame to the folded configuration.

What is claimed is: 
     
         1 . A foldable stroller with a frame assembly reconfigurable between an unfolded configuration and a folded configuration and having left and right frame sides, the left and right frame sides each comprising:
 a fold joint;   a handle push arm slidably coupled to the fold joint;   a front leg arranged substantially parallel to the handle push arm and having an upper end connected to the fold joint;   a slide collar fixed to the front leg and defining an opening, the handle push arm slidably received through the opening;   a rear leg extending down from and pivotally connected to the fold joint; and   a drive link with a rear end pivotally coupled to the rear leg below the fold joint and a front end pivotally coupled to a lower end of the push arm,   wherein, when reconfigured from the unfolded configuration to the folded configuration, the handle push arm slides downward relative to the fold joint and the slide collar, and the rear end of the drive link and the rear leg move toward the front leg and the handle push arm, and   wherein, in the folded configuration, the rear leg lies closely adjacent to and substantially parallel with the front leg and the handle push arm.   
     
     
         2 . A foldable stroller according to  claim 1 , wherein the left and right side drive links draw the respective left and right rear legs and front legs toward and generally parallel to one another when the stroller frame assembly is moved to the folded configuration. 
     
     
         3 . A foldable stroller according to  claim 1 , further comprising a drive mechanism on at least one of the left or right frame sides and configured to bias the frame assembly toward the folded configuration. 
     
     
         4 . A foldable stroller according to  claim 3 , wherein the drive mechanism is connected to a pivot joint between the drive link on the at least one of the left or right frame sides and the corresponding rear leg. 
     
     
         5 . A foldable stroller according to  claim 3 , wherein the drive mechanism has a pre-loaded resilient biasing element. 
     
     
         6 . A foldable stroller according to  claim 3 , wherein the drive mechanism has a torsion spring. 
     
     
         7 . A foldable stroller according to  claim 3 , wherein the drive mechanism has a torsion spring acting on a rear end of the drive link on the at least one of the left or right frame sides and the corresponding rear leg. 
     
     
         8 . A foldable stroller according to  claim 1 , further comprising a left drive mechanism on the left frame side and a right drive mechanism on the right frame side and each of the left and right drive mechanisms configured to bias the frame assembly toward the folded configuration. 
     
     
         9 . A foldable stroller according to  claim 3 , further comprising a fold latch on each the left and right frame sides, each fold latch being actuable from a latched condition retaining the frame assembly in the unfolded configuration to a released configuration whereby the drive mechanism assists in moving the frame assembly to the folded configuration. 
     
     
         10 . A foldable stroller according to  claim 1 , wherein the rear legs remain generally upright as the frame assembly is moved from the unfolded configuration to the folded configuration, and wherein the foldable stroller stands upright in the folded configuration. 
     
     
         11 . A foldable stroller according to  claim 1 , wherein the handle push arms slide parallel to the front legs when the frame assembly is moved between the unfolded and folded configurations. 
     
     
         12 . A foldable stroller according to  claim 1 , wherein lower ends of the handle push arms extend below lower ends of the front legs when the frame assembly is in the folded configuration and standing upright. 
     
     
         13 . A foldable stroller according to  claim 12 , wherein the foldable stroller stands upright on front wheels positioned at the lower ends of the front legs and on the lower ends of the push arms. 
     
     
         14 . A foldable stroller according to  claim 1 , wherein the foldable stroller, in the folded configuration, stands upright on front wheels positioned at lower ends of the front legs and on either lower ends of the handle push arms, the front ends of the drive links, or contact surfaces defined thereat in the folded configuration. 
     
     
         15 . A foldable stroller with a frame assembly reconfigurable between an unfolded configuration and a folded configuration and having left and right frame sides, the left and right frame sides each comprising:
 a fold joint;   a handle push arm slidably coupled to the fold joint;   a front leg arranged substantially parallel to the handle push arm and having an upper end connected to the fold joint;   a rear leg extending down from and pivotally connected to the fold joint;   a drive link with a rear end pivotally coupled to the rear leg below the fold joint and a front end pivotally coupled to a lower end of the push arm; and   a drive mechanism operably coupled to part of the frame assembly and configured to assist in moving the frame assembly toward the folded configuration,   wherein, when reconfigured from the unfolded configuration to the folded configuration, the handle push arm slides downward relative to the fold joint, and the rear end of the drive link and the rear leg move toward the front leg and the handle push arm, and   wherein, in the folded configuration, the rear leg lies closely adjacent to and substantially parallel with the front leg and the handle push arm.   
     
     
         16 . A foldable stroller according to  claim 15 , further comprising:
 a left fold latch on the left frame side;   a right fold latch on the right frame side; and   an actuator coupled to both the left and right handle push arms, the actuator actuable to move both the left and right fold latches from a latched condition retaining the frame assembly in the unfolded configuration to a released condition permitting the frame assembly to move to the folded configuration.   
     
     
         17 . A foldable stroller according to  claim 16 , wherein the drive mechanism automatically moves the frame assembly toward the folded configuration when the left and right fold latches are actuated to the released condition. 
     
     
         18 . A foldable stroller according to  claim 15 , wherein the drive mechanism includes a torsion spring acting on a rear end of the drive link on each of the left and right frame sides. 
     
     
         19 . A foldable stroller according to  claim 15 , wherein each of the left and right frame sides also has a slide collar fixed to the respective front leg and defining an opening, the corresponding handle push arm slidably received through the opening. 
     
     
         20 . A foldable stroller according to  claim 15 , wherein each of the drive links is substantially linear when viewed from either side of the frame assembly, and wherein the handle push arms and the respective front legs slide parallel to one another when the frame assembly is moved between the folded and unfolded configurations.