Sunshade assembly

Abstract

A sunshade assembly includes a winding shaft, a sunshade curtain wound around the winding shaft, a pull rod connected to a sunshade curtain end distal from the winding shaft, and two guide rail units. Each guide rail unit includes a guide rail having a guide surface. A link unit includes a connecting shaft, and two guide wheels respectively attached to the connecting shaft. Each guide wheel has a rolling surface to roll on the respective guide surface. One of the rolling surface and the guide surface has a guide groove. The other of the rolling surface and the guide surface protrudes into the guide groove. A resistance unit provides a resisting force against rotation of the connecting shaft.

What is claimed is: 
     
         1 . A sunshade assembly, comprising:
 two spaced-apart mounting seats;   a winding shaft mounted rotatably between said mounting seats;   a sunshade curtain extendably wound around said winding shaft;   a pull rod connected to one end of said sunshade curtain that is distal from said winding shaft;   two guide rail units, each of which includes a guide rail, said guide rail having a guide surface extending along the length of said guide rail;   a link unit including a connecting shaft mounted rotatably to said pull rod and having two opposite ends, and two guide wheels respectively attached to said two opposite ends of said connecting shaft, each of said guide wheels having a rolling surface to roll on said guide surface of one of said guide rails, one of said rolling surface and said guide surface having a guide groove, the other one of said rolling surface and said guide surface protruding into said guide groove; and   a resistance unit including a base mounted to said pull rod and frictionally contacting said connecting shaft to provide a resisting force against rotation of said connecting shaft.   
     
     
         2 . The sunshade assembly as claimed in  claim 1 , wherein said guide surface has said guide groove, and said rolling surface protrudes into said guide groove. 
     
     
         3 . The sunshade assembly as claimed in  claim 2 , wherein said guide groove is designed by an arcuate groove-defining wall surface. 
     
     
         4 . The sunshade assembly as claimed in  claim 1 , wherein said link unit further includes two resilient press members respectively and resiliently pressing said guide wheels against said guide surfaces of said guide rails. 
     
     
         5 . The sunshade assembly as claimed in  claim 4 , wherein said base includes two spaced-apart base walls, and a connecting wall that interconnects said base walls and that cooperates with said base walls to define an open channel, said open channel having an insert portion proximate to said connecting wall, and an open portion distal from said connecting wall, said connecting shaft being inserted through said insert portion and being sandwiched between said base walls. 
     
     
         6 . The sunshade assembly as claimed in  claim 5 , wherein said insert portion has a configuration substantially corresponding to that of said connecting shaft. 
     
     
         7 . The sunshade assembly as claimed in  claim 5 , wherein said pull rod is a hollow rod, said resistance unit being disposed inside said hollow rod, said resistance unit further including a fastener to secure said base to said pull rod, said fastener being configured as a bolt that extends through said pull rod and that engages threadedly said base walls at portions distal from said connecting wall. 
     
     
         8 . The sunshade assembly as claimed in  claim 7 , wherein each of said guide rail units further includes an elongate frame of substantially U-shaped cross section, said frame having a main wall, and first and second sidewalls extending transversely and respectively from two opposite ends of said main wall towards the other one of said guide rail units, said guide rail being disposed on said first sidewall, each of said resilient press members including two bracket plates that are sleeved onto said connecting shaft on two opposite sides of a corresponding one of said guide wheels, a connecting section that interconnects ends of said bracket plates between a corresponding one of said guide wheels and said second sidewall, and at least one resilient abutment section that is curved outwardly from said bracket plates in proximity to said connecting section and that presses resiliently said second sidewall so that said corresponding one of said guide wheels is pushed against said guide surface. 
     
     
         9 . The sunshade assembly as claimed in  claim 1 , wherein said rolling surface has said guide groove, and said guide surface protrudes into said guide groove. 
     
     
         10 . The sunshade assembly as claimed in  claim 1 , wherein said guide surface has a protrusion of trapezoidal cross section, and said guide groove is a trapezoidal groove conforming to said protrusion.