Seat lifting devices

Abstract

Seat lifting devices disposed between a seat support for supporting a seat cushion and a seat mount for mounting the seat support in order to vertically adjust the seat cushion are taught that comprise a first linking mechanism movably interconnecting the seat support and the seat mount. The first linking mechanism comprises first and second linking arms that are respectively pivotally connected to the seat mount and the seat support via pivot axes. One of the pivot axes of the second linking arm comprises a movable pivot axis that is arranged and constructed to move along the second linking arm and to engage the second linking arm, so that substantial length of the second linking arm can be changed when the movable pivot axis moves along the second linking arm.

1 . A seat lifting device disposed between a seat support for supporting a seat cushion and a seat mount for mounting the seat support in order to vertically adjust the seat cushion, comprising: 
 a first linking mechanism movably interconnecting the seat support and the seat mount, the first linking mechanism comprising first and second linking arms that are respectively pivotally connected to the seat mount and the seat support via pivot axes,    wherein one of the pivot axes of the second linking arm comprises a movable pivot axis that is arranged and constructed to move along the second linking arm and to engage the second linking arm, so that substantial length of the second linking arm can be changed when the movable pivot axis moves along the second linking arm.    
     
     
         2 . A seat lifting device as defined in  claim 1 , wherein the second linking arm comprises a threaded shaft that is pivotally connected to the seat mount and the seat support and a gear assembly having a nut that engages the threaded shaft, the gear assembly is arranged and constructed to move along the threaded shaft, and wherein the movable pivot axis is mechanically connected to the gear assembly, so as to move along the threaded shaft when the gear assembly moves along the threaded shaft.  
     
     
         3 . A seat lifting device disposed between a seat support for supporting a seat cushion and a seat mount for mounting the seat support in order to vertically adjust the seat cushion, comprising: 
 a pair of first linking mechanisms movably interconnecting the seat support and the seat mount, at least one of the first linking mechanisms comprising first and second linking arms that are respectively pivotally connected to the seat mount and the seat support via pivot axes,    wherein one of the pivot axes of the second linking arm comprises a movable pivot axis that is arranged and constructed to move along the second linking arm and to engage the second linking arm, so that substantial length of the second linking arm can be changed when the movable pivot axis moves along the second linking arm.    
     
     
         4 . A seat lifting device as defined in  claim 3 , wherein the second linking arm comprises a threaded shaft that is pivotally connected to the seat mount and the seat support and a gear assembly having a nut that engages the threaded shaft, the gear assembly is arranged and constructed to move along the threaded shaft, and wherein the movable pivot axis is mechanically connected to the gear assembly, so as to move along the threaded shaft when the gear assembly moves along the threaded shaft.  
     
     
         5 . A seat lifting device as defined in  claim 4  further comprising a second linking mechanism movably interconnecting the seat support and the seat mount, wherein the second linking mechanism comprises an elongated guide slot formed in the seat mount and a guide pin attached to the seat support, and wherein the guide pin slidably engages the guide slot.  
     
     
         6 . A seat lifting device as defined in  claim 2  further comprising an actuator, wherein the actuator is arranged and constructed to drive the gear assembly, thereby moving the gear assembly and the movable pivot axis attached thereto along the threaded shaft.  
     
     
         7 . A seat lifting device as defined in  claim 4  further comprising an actuator, wherein the actuator is arranged and constructed to drive the gear assembly, thereby moving the gear assembly and the movable pivot axis attached thereto along the threaded shaft.  
     
     
         8 . A seat lifting device as defined in  claim 5  further comprising an actuator, wherein the actuator is arranged and constructed to drive the gear assembly, thereby moving the gear assembly and the movable pivot axis attached thereto along the threaded shaft.  
     
     
         9 . A seat lifting device disposed between a seat support for supporting a seat cushion and a seat mount for mounting the seat support in order to vertically adjust the seat cushion, comprising: 
 a pair of first linking mechanisms movably interconnecting the seat support and the seat mount, at least one of the first linking mechanisms comprising first and second linking arms that are respectively pivotally connected to the seat mount and the seat support via pivot axes; and    a second linking mechanism movably interconnecting the seat support and the seat mount, the second linking mechanism comprising an elongated guide slot formed in the seat mount and a guide pin attached to the seat support, the guide pin slidably engaging the guide slot,    wherein one of the pivot axes of the second linking arm comprises a movable pivot axis that is arranged and constructed to move along the second linking arm and to engage the second linking arm, so that substantial length of the second linking arm can be changed when the movable pivot axis moves along the second linking arm, wherein the second linking arm comprises a threaded shaft that is pivotally connected to the seat mount and the seat support and a gear assembly having a nut that engages the threaded shaft, the gear assembly is arranged and constructed to move along the threaded shaft, and wherein the movable pivot axis is mechanically connected to the gear assembly, so as to move along the threaded shaft when the gear assembly moves along the threaded shaft.    
     
     
         10 . A seat lifting device as defined in  claim 1 , wherein the first and second linking arms are connected to the seat support via a common pivot axis, and wherein the first and second linking arms are respectively connected to the seat mount via first and second pivot axes, the second pivot axis is positioned behind the first pivot axis.  
     
     
         11 . A seat lifting device as defined in  claim 3 , wherein the first and second linking arms are connected to the seat support via a common pivot axis, and wherein the first and second linking arms are respectively connected to the seat mount via first and second pivot axes, the second pivot axis is positioned behind the first pivot axis.  
     
     
         12 . A seat lifting device as defined in  claim 9 , wherein the first and second linking arms are connected to the seat support via a common pivot axis, and wherein the first and second linking arms are respectively connected to the seat mount via first and second pivot axes, the second pivot axis is positioned behind the first pivot axis.  
     
     
         13 . A seat lifting device as defined in  claim 2 , wherein the first linking mechanism is positioned adjacent to a seatbelt connecting position on the seat support.  
     
     
         14 . A seat lifting device as defined in  claim 4 , wherein the first linking mechanism is positioned adjacent to a seatbelt connecting position on the seat support.  
     
     
         15 . A seat lifting device as defined in  claim 5 , wherein the first linking mechanism is positioned adjacent to a seatbelt connecting position on the seat support.  
     
     
         16 . A seat lifting device as defined in  claim 9 , wherein the first linking mechanism is positioned adjacent to a seatbelt connecting position on the seat support.