A lift machine comprises a base, a support for supporting a load above the base, a lift actuator operatively connected between the base and the support for raising and lowering the support relative to the base, and a support stabilization mechanism operatively connected between the base and the support for stabilizing the support relative to the base during raising and lowering of the support by the lift actuator. The support stabilization mechanism comprises a pair of opposed linkages, with each of the pair of opposed linkages having a lower torque tube link and an upper torque tube link. The lower torque tube link has a torque tube operatively pivoted to the base. The upper torque tube link has a torque tube operatively pivoted to the support. The pair of opposed linkages are interconnected in such a manner that the pair moves in synchronization during raising and lowering of the support by the lift actuator and maintains the support substantially level even in the event that the center of mass of the load is offset from a vertical axis of the lift actuator.
1. A lift machine comprising:
a base,
a support for supporting a load above said base,
a lift actuator operatively connected between said base and said support for raising and lowering said support relative to said base, and
a support stabilization mechanism operatively connected between said base and said support for stabilizing said support relative to said base during raising and lowering of said support by said lift actuator, said support stabilization mechanism comprising a pair of opposed linkages, each of said pair of opposed linkages having a lower torque tube link and an upper torque tube link, said lower torque tube link having a torque tube operatively pivoted to said base, said upper torque tube link having a torque tube operatively pivoted to said support,
said pair of opposed linkages being interconnected in such a manner that said pair moves in synchronization during raising and lowering of said support by said lift actuator and maintains said support substantially level even in the event that the center of mass of the load is offset from a vertical axis of said lift actuator,
wherein each of said lower and upper torque tube links has a pair of link arms, said link arms of said lower torque tube links being operatively pivoted to said link arms of said upper torque tube links,
wherein each of said pair of opposed linkages further includes a lower link and an upper link, said upper link having a first end operatively pivoted to one of said pair of link arms of said upper torque tube link and a second end operatively pivoted to a first end of said lower link, said lower link having a second end cooperating with said base in such a manner as to permit translation of said second end of said lower link relative to said base during raising and lowering of said support by said lift actuator.
2. The lift machine of claim 1 wherein said second end of said lower link has a roller thereon which operatively rolls along said base.
3. The lift machine of claim 1 wherein said stabilization mechanism further includes a connecting link for interconnecting said pair of opposed linkages, said connecting link having first and second ends, said first end of said connecting link operatively pivoted to said second end of said upper link of one of said pair of opposed linkages and to said first end of said lower link of said one pair of opposed linkages, said second end of said connecting link operatively pivoted to said second end of said upper link of the other of said pair of opposed linkages and to said first end of said lower link of said other pair of opposed linkages.
4. The lift machine of claim 3 wherein said link arms of said lower and upper torque tube links cooperate with said connecting link in such a manner as to permit translation of said link arms relative to said connecting link during raising and lowering of said support by said lift actuator.
5. The lift machine of claim 4 wherein said link arms each have a roller thereon which operatively rolls along said connecting link.
6. The lift machine of claim 5 wherein said connecting link includes a lateral recess therein and wherein said roller rolls in said recess.
7. The lift machine of claim 1 wherein said lift actuator is a hydraulic cylinder.
8. The lift machine of claim 1 wherein said lift actuator is a push chain.
9. The lift machine of claim 1 wherein said lift actuator is a spiral lift.
10. Apparatus for lifting and supporting an automotive chassis in position to be assembled with an automotive body along a moving assembly line, said apparatus comprising:
a mobile vehicle, and
a lift machine carried by said mobile vehicle, said lift machine comprising:
a base,
a support for supporting a load above said base,
a lift actuator operatively connected between said base and said support for raising and lowering said support relative to said base, and
a support stabilization mechanism operatively connected between said base and said support for stabilizing said support relative to said base during raising and lowering of said support by said lift actuator, said support stabilization mechanism comprising a pair of opposed linkages, each of said pair of opposed linkages having a lower torque tube link and an upper torque tube link, said lower torque tube link having a torque tube operatively pivoted to said base, said upper torque tube link having a torque tube operatively pivoted to said support,
said pair of opposed linkages being interconnected in such a manner that said pair moves in synchronization during raising and lowering of said support by said lift actuator and maintains said support substantially level even in the event that the center of mass of the load is offset from a vertical axis of said lift actuator,
wherein each of said lower and upper torque tube links has a pair of link arms, said link arms of said lower torque tube links being operatively pivoted to said link arms of said upper torque tube links,
wherein each of said pair of opposed linkages further includes a lower link and an upper link, said upper link having a first end operatively pivoted to one of said pair of link arms of said upper torque tube link and a second end operatively pivoted to a first end of said lower link, said lower link having a second end cooperating with said base in such a manner as to permit translation of said second end of said lower link relative to said base during raising and lowering of said support by said lift actuator.
11. The apparatus of claim 10 wherein said second end of said lower link has a roller thereon which operatively rolls along said base.
12. The apparatus of claim 10 wherein said stabilization mechanism further includes a connecting link for interconnecting said pair of opposed linkages, said connecting link having first and second ends, said first end of said connecting link operatively pivoted to said second end of said upper link of one of said pair of opposed linkages and to said first end of said lower link of said one pair of opposed linkages, said second end of said connecting link operatively pivoted to said second end of said upper link of the other of said pair of opposed linkages and to said first end of said lower link of said other pair of opposed linkages.
13. The apparatus of claim 12 wherein said link arms of said lower and upper torque tube links cooperate with said connecting link in such a manner as to permit translation of said link arms relative to said connecting link during raising and lowering of said support by said lift actuator.
14. The apparatus of claim 13 wherein said link arms each have a roller thereon which operatively rolls along said connecting link.
15. The apparatus of claim 14 wherein said connecting link includes a lateral recess therein and wherein said roller rolls in said recess.
16. The apparatus of claim 10 wherein said lift actuator is a hydraulic cylinder.
17. The apparatus of claim 10 wherein said lift actuator is a push chain.
18. The apparatus of claim 10 wherein said lift actuator is a spiral lift.