Reciprocally movable carrier

Abstract

A reciprocally movable carrier includes several frame rods interconnecting a bottom seat and a swingable frame, a swingable mechanism having a first swing arm unit, a second swing arm unit pivoted to the bottom seat via a pivot shaft in such that the second swing arm unit is connected pivotally to the first swing arm unit and the swingable frame so that the first and second swing arm units simultaneously move when the second swing arm unit swings about the pivot shaft, a swing adjustment mechanism including a displacement member movable together with one end of the first swing arm unit along a length of the second swing arm in order to alter a distance between the end of the first swing arm unit and the pivot shaft of the second swing arm unit, thereby moving the swingable frame in forward and rearward directions or in a wavy manner.

What is claimed is: 
     
         1 . A reciprocally movable carrier including:
 a bottom seat;   a swingable frame mounted swingably on the bottom seat;   a swingable mechanism disposed between the bottom seat and the swingable frame in such a manner to reciprocally moving the swingable frame relative to the bottom seat in forward and rearward directions; and   a swing connection structure disposed movably between the bottom seat and the swingable frame, including a plurality of frame rods interconnecting two lateral sides of the bottom seat and two lateral sides of the swingable frame such that each lateral side of the bottom seat and the swingable frame and two of the frame rods cooperatively form a rectangular connection rod structure.   
     
     
         2 . The reciprocally movable carrier according to  claim 1 , wherein each of the frame rods has an upper end and a lower end respectively and pivotally connected to the swingable frame and the bottom seat, thereby forming a parallel rectangular connection rod structure. 
     
     
         3 . The reciprocally movable carrier according to  claim 1 , wherein each of the frame rods has a lower end connected to a respective one of the lateral sides of the bottom seat via a pivot pin and an upper end connected pivotally a respective lateral side of the swingable frame such that the frame rods, the bottom seat and the frame rods cooperatively form a non-parallel rectangular connection rod structure. 
     
     
         4 . The reciprocally movable carrier according to  claim 3 , wherein the non-parallel rectangular connection rod structure has an upper part and a lower part having a width smaller than the upper part. 
     
     
         5 . The reciprocally movable carrier according to  claim 3 , wherein the non-parallel rectangular connection rod structure has an upper part and a lower part having a width greater than the upper part. 
     
     
         6 . The reciprocally movable carrier according to  claim 1 , further comprising a swing adjustment mechanism including a first swing arm unit mounted pivotally on the bottom seat so as to be driven by a first driving source, a second swing arm unit pivotally connected to the bottom seat via a pivot shaft such that said second arm unit is pivotally connected to one end of the first swing arm unit and the swingable frame in such a manner to cause simultaneous movement of the end of the first swing arm unit and the second swing arm unit relative to the bottom seat, thereby altering a distance between the end of the first swing arm unit and the pivot shaft of the second swing arm unit. 
     
     
         7 . The reciprocally movable carrier according to  claim 6 , wherein the bottom seat has a central portion provided with two parallel partitions defining a receiving space to accommodate the swingable mechanism and the swing adjustment mechanism therein. 
     
     
         8 . The reciprocally movable carrier according to  claim 6 , wherein the swingable mechanism further includes a crankshaft mounted on the bottom seat and driven by the first driving source, the first swing arm unit being pivotally connected to the crankshaft such that rotation of the crankshaft simultaneously drives the first swing arm unit reciprocally in forward and rearward directions. 
     
     
         9 . The reciprocally movable carrier according to  claim 8 , wherein the first driving source includes a first motor mounted on the bottom seat, the first motor having an output shaft coupled to the crankshaft via a transmission structure. 
     
     
         10 . The reciprocally movable carrier according to  claim 9 , wherein the transmission structure includes a first drive shaft and a first transmission belt trained around the first drive shaft and the output shaft of the first motor, a second drive shaft and a second transmission belt trained around the first and second drive shafts, and a third transmission belt trained around the second drive shaft and the crankshaft. 
     
     
         11 . The reciprocally movable carrier according to  claim 6 , wherein the second swing arm unit has an upper end provided with a pivot shaft, the swingable frame further including a connection element which is connected pivotally to the pivot shaft. 
     
     
         12 . The reciprocally movable carrier according to  claim 6 , wherein a guiding slot is formed along longitudinal length of the second swing arm unit, a movable rod being provided to the end of the first swing arm unit such that the movable rod extends through the guiding slot, the displacement member further including a displacement element disposed adjacent to the second swing arm unit and having a pivot end connected pivotally to the movable rod such that sliding action of the movable rod within the guiding slot simultaneously results in movement of the displacement element together with the movable rod. 
     
     
         13 . The reciprocally movable carrier according to  claim 12 , wherein the swing adjustment mechanism further includes a second driving source, a screw shaft, a second motor for driving the screw shaft, the displacement element having a screw coupler sleeved rotatably around the screw shaft such that activation of the second motor results in rotation of the screw shaft, thereby driving the displacement element and the movable rod within the guiding slot in the second swing arm unit. 
     
     
         14 . The reciprocally movable carrier according to  claim 1 , further comprising a carrier plate disposed above the swingable frame.