Safety vehicle seat structure

Abstract

A safety vehicle seat structure comprising a seat having a backrest and a seat portion. A support frame is secured to the seat and comprises a pair of spaced-apart vertical back support members each pivotally secured at their upper ends to a respective side of the backrest. Each vertical back support member has a lower end secured to a respective one of two horizontal supports located below the seat portion. At least one connecting member is secured to the seat portion forwardly of the back support members and extends therebelow to pivotally interconnect with a displaceable lever framework whereby actuation of the lever framework will cause displacement of the seat between two positions relative to the support frame. A belt attachment clamp is secured to the horizontal support members and adapted to receive and rigidly engage a portion of a retaining belt extending therethrough. A safety strap structure is also provided for immovably securing the seat and support frame to a rigid external structure and further provides shock absorbing means for damping the forward movement of a person's body when subjected to a shock.

I claim: 
     
       1. A safety vehicle seat structure comprising a seat having a backrest and a seat portion, a support frame secured to said seat, said support frame comprising a pair of spaced apart vertical back support members each pivotally secured at their upper ends .Iadd.to an end of a respective pivoting link, the other end of said pivoting link being pivotally secured .Iaddend.to a respective side of said backrest, each said vertical back support members having a lower end secured to a respective one of two horizontal support members located below said seat portion, at least one connecting member secured to said seat portion forwardly of said back support members and extending therebelow to pivotally interconnect with a displaceable lever framework whereby actuation of said lever framework will cause displacement of said seat between two positions relative to said support frame, said displaceable lever framework including a frame having opposed parallel arms and an interconnecting arm connected between said opposed arms, each said opposed parallel arms being pivotally interconnected near said interconnecting arm to a respective one of said two horizontal support members below said seat portion, one of said opposed arms being pivotally interconnected at its free end with said at least one connecting member, one of said opposed arms being lockable with one of said horizontal support members. 
     
     
       2. A safety vehicle seat as claimed in claim 1 wherein one of said opposed arms is provided with a lever arm for actuation of said displaceable framework. 
     
     
       3. A safety vehicle seat as claimed in claim 2 wherein said lever arm is releasably locked with one of said horizontal support members whereby to rigidly secure said support frame in two different configurations to support said seat in two different positions. 
     
     
       4. A safety vehicle seat structure as claimed in claim 1 wherein a belt attachment clamp is secured to said support frame below said seat portion and adapted to receive and rigidly engage a portion of a retaining belt extending therethrough and secured to a vehicle frame. 
     
     
       5. A safety vehicle seat structure as claimed in claim 4 wherein said belt attachment clamp comprises a base channel member having two parallel side walls, a hook member at one end of said base channel and having a hook end, a wedge element pivotally secured at one end to the other end of said base channel member between sid two parallel side walls, the other end of said wedge element being pivotally connected to a clamp lever plate having an attaching loop adapted to engage with said hook end and rigidly secure said wedge element in said base channel with said lever plate thereover whereby to rigidly secure a portion of a belt positioned acros said two parallel side walls of said base channel and under said wedge element. 
     
     
       6. A safety vehicle seat structure as claimed in claim 1 further comprising a safety strap structure for immovably securing said seat and support frame to a rigid external structure, said safety strap structure having shock absorbing means for damping the forward movement of a person's body when subjected to a shock. 
     
     
       7. A safety vehicle seat structure as claimed in claim 6 wherein said safety strap structure comprises two shoulder straps each having said shock absorbing means therein, said shoulder straps being guided over a respective shoulder of a person sitting in said seat and extending frontwardly downward of said person, said two shoulder straps each being rigidly secured at one end to said rigid external structure, and at its other end to a further strap extending about said seat portion. 
     
     
       8. A safety vehicle seat structure as claimed in claim 7 wherein said shock absorbing expandable means comprises a section of said shoulder strap being folded in abutment and aligned relationship to define two abuting strap sections, said two sections being secured to each other by a plurality of spaced apart transverse rows of stitches whereby a predetermined force applied along the longitudinal axis of said shoulder strap will cause said rows of stitches to break in sequential order as said section of strap detaches itself. 
     
     
       9. A safety vehicle seat structure as claimed in claim 7 wherein guide apertures are provided in an upper part of said backrest for receiving a respective shoulder strap therethrough, said expandable means being located behind said backrest between a shoulder strap upper end and an associated guide aperture, each said shoulder strap upper end being attached to a strap connector, an adjustable seat attachment strap secured between said strap connector and said backrest, and an adjustable securing strap having a connector at one end secured to said rigid external structure, the outer end of said securing strap being adjustably connected to said strap connector. 
     
     
       10. A safety vehicle seat structure as claimed in claim 9 wherein said securing strap is connected to said strap connector by a hook plate member having a hook plate with a flat wall portion and a hook flange at one end thereof securable to said strap connector, an aperture through said flat wall portion, a cover plate retained in juxtaposition with said flat wall portion, a strap receiving slot in said cover plate in registry with said aperture in said flat wall, means for retaining said cover plate over said flat wall portion of said hook plate, said securing strap having a portion thereof secured to said strap connector by passing said strap below said flat wall portion of said hook plate through said aperture and over a leading edge of said cover plate and through said slot and aperture whereby said strap is in juxtaposition beneath said hook plate and extends rearwardly thereof from said secured position. 
     
     
       11. A safety vehicle seat structure as claimed in claim 7 wherein both said shoulder straps are each secured at a lower end thereof above said seat portion to a respective connector plate of a further strap connector, a further adjustable belt extending transversely through vertical side walls of said seat and spaced above said seat, said further adjustable strap being secured to both said connector plates to form a loop passing above and below said seat, and a further strap secured at one end to aligned slots in juxtaposed positions of said connector plates and at another end to said further adjustable strap under said seat portion. 
     
     
       12. A safety vehicle seat structure comprising a seat having a backrest and a seat portion, a support frame secured to said seat, said support frame comprising a pair of spaced apart vertical back support members each pivotally secured at their upper ends to a respective side of said backrest, each said vertical back support members having a lower end secured to a respective one of two horizontal support members located below said seat portion, at least one connecting member secured to said seat portion forwardly of said back support members and extending therebelow to pivotally interconnect with a displaceable lever framework whereby actuation of said lever framework will cause displacement of said seat between two positions relative to said support frame, said upper end of each said vertical support members being pivotally interconnected to a respective side of said backrest through a pivoting link pivotally secured at one end to said vertical support member upper end and pivotally secured at its other end to a protective side wall of said backrest, said seat side wall being forwardly projecting and of channel cross-section defining two spaced apart walls, said link being pivotally secured in a channel bracket secured between said spaced apart walls to a rigid pivotal connection in said channel bracket.