Seat suspension
View Patent ↗A seat support mechanism that is adapted to constrain motion of a bottom of a seat relative to a floor as the seat bottom moves up and down relative to the floor, where the seat has a seat back, and where the seat is constructed and arranged to support an occupant thereof above the floor, wherein the seat bottom has a front edge, and wherein the seat bottom supports the occupant's thighs with the knees in front of the front edge of the seat bottom. The seat support mechanism is constructed and arranged such that as the seat bottom is moved up and down, the seat support mechanism causes the seat bottom to pivot about a virtual lateral horizontal pivot axis located farther from the front edge of the seat bottom than the occupant's knees. The seat support mechanism is further constructed and arranged such that the back of the seat remains at a relatively constant angle to the floor as the seat bottom moves up and down and pivots.
1. A seat support mechanism that is adapted to constrain motion of a bottom of a seat relative to a floor as the seat bottom moves up and down relative to the floor, where the seat has a seat back, and where the seat is constructed and arranged to support an occupant thereof above the floor, wherein the seat bottom has a front edge, and wherein the seat bottom supports the occupant's thighs with the knees in front of the front edge of the seat bottom, the seat support mechanism comprising:
mechanical structure that is constructed and arranged such that as the seat bottom is moved up and down, the seat bottom is caused to pivot about a virtual lateral horizontal pivot axis located in front of the front edge of the seat bottom, while the seat back remains at a relatively constant angle to the floor;
wherein the mechanical structure comprises:
a seat back support structure that mechanically supports the seat back;
a scissor mechanism mechanically coupled to the seat back support structure and the floor; wherein the scissor mechanism comprises first and second structural members; wherein the first structural member comprises a first end that is fixed in height relative to the floor and is arranged to pivot about a first pivot axis, and a second end that can move up and down relative to the floor and is pivotably coupled to the seat back support structure; and wherein the second structural member comprises a first end, and a second end that can move up and down relative to the floor and is pivotably coupled to the seat back support structure; and wherein the first and second structural members are pivotably coupled together at a location between their respective first and second ends; and
a seat bottom support member with a first end that supports the seat bottom and a second end that is coupled to the scissor mechanism.
2. The seat support mechanism of claim 1 wherein the mechanical structure allows the location of the virtual pivot axis to be varied.
3. The seat support mechanism of claim 1 wherein the seat bottom support member is coupled to the seat bottom at an adjustable angle.
4. The seat support mechanism of claim 3 wherein the seat bottom support member is coupled to a curved bearing surface of the scissor mechanism.
5. The seat support mechanism of claim 4 wherein the second end of the seat bottom support member is coupled to the curved bearing surface at a coupling location, and wherein the curved bearing surface is an arc with a radius of curvature approximately equal to the length of the seat bottom support member.
6. The seat support mechanism of claim 1 wherein the seat faces in a seat facing direction, and wherein the virtual pivot axis is horizontal, and perpendicular to the seat facing direction.
7. The seat support mechanism of claim 1 , wherein the second end of the first structural member of the scissor mechanism is indirectly connected to the seat back support structure by a link that is pivotably coupled to both the second end of the first structural member of the scissor mechanism and the seat back support structure.
8. The seat support mechanism of claim 7 wherein all of the pivot axes are horizontal and perpendicular to the seat facing direction.
9. The seat support mechanism of claim 1 wherein the seat bottom is generally horizontal at a first height, and the seat support mechanism causes the front of the seat to tilt downward as the seat is moved above the first height.
10. The seat support mechanism of claim 1 wherein the seat bottom is at an angle to the horizontal, and wherein the seat support mechanism is adapted to cause the angle of the seat bottom to the horizontal to vary linearly as a function of height from the floor.
11. The seat support mechanism of claim 1 wherein the seat bottom is at an angle to the horizontal, and wherein the seat support mechanism is adapted to cause the angle of the seat bottom to the horizontal to vary non-linearly as a function of height from the floor.
12. The seat support mechanism of claim 11 wherein the seat support mechanism is adapted to cause the seat bottom angle to the horizontal to change more as it is moved above the first height as compared to when it is moved below the first height.
13. The seat support mechanism of claim 1 wherein the seat bottom support member is pivotably coupled to the seat bottom, and is pivotably coupled to the scissor mechanism.
14. The seat support mechanism of claim 1 wherein the mechanical structure further comprises a fixed support member that is coupled to the floor, and wherein the first end of the first structural member of the scissor mechanism is pivotably coupled to the fixed support member.
15. The seat support mechanism of claim 14 wherein the mechanical structure further comprises a link that is pivotably coupled to both the fixed support member and the first end of the second structural member of the scissor mechanism.
16. A seat support mechanism that is adapted to constrain motion of a bottom of a seat relative to a floor as the seat bottom moves up and down relative to the floor, where the seat has a seat back, and where the seat is constructed and arranged to support an occupant thereof above the floor, wherein the seat bottom has a front edge, and wherein the seat bottom supports the occupant's thighs with the knees in front of the front edge of the seat bottom, the seat support mechanism comprising:
mechanical structure that is constructed and arranged such that as the seat bottom is moved up and down, the seat bottom is caused to pivot about a virtual lateral horizontal pivot axis located in front of the front edge of the seat bottom, while the seat back remains at a relatively constant angle to the floor;
wherein the mechanical structure comprises:
a seat back support structure that mechanically supports the seat back;
a scissor mechanism mechanically coupled to the seat back support structure and the floor; wherein the scissor mechanism comprises first and second structural members; wherein the first structural member comprises a first end that is fixed in height relative to the floor and is arranged to pivot about a first pivot axis, and a second end that can move up and down relative to the floor and is indirectly connected to the seat back support structure by a link that is pivotably coupled to both the second end of the first structural member and the seat back support structure; and wherein the second structural member comprises a first end, and a second end that can move up and down relative to the floor and is pivotably coupled to the seat back support structure; and wherein the first and second structural members are pivotably coupled together at a location between their respective first and second ends; and
a seat bottom support member with a first end that is coupled to the seat bottom at an adjustable angle, and a second end that is coupled to the scissor mechanism.
17. A seat support mechanism that is adapted to, constrain motion of a bottom of a seat relative to a floor as the seat bottom moves up and down relative to the floor, where the seat has a seat back, and where the seat is constructed and arranged to support an occupant thereof above the floor, wherein the seat bottom has a front edge, and wherein the seat bottom supports the occupant's thighs with the knees in front of the front edge of the seat bottom, the seat support mechanism comprising:
mechanical structure that is constructed and arranged such that as the seat bottom is moved up and down, the seat bottom is caused to pivot about a virtual lateral horizontal pivot axis located in front of the front edge of the seat bottom, while the seat back remains at a relatively constant angle to the floor;
wherein the mechanical structure comprises:
a seat back support structure that mechanically supports the seat back;
a scissor mechanism mechanically coupled to the seat back support structure and the floor; wherein the scissor mechanism comprises first and second structural members; wherein the first structural member comprises a first end that is fixed in height relative to the floor and is arranged to pivot about a first pivot axis, and a second end that can move up and down relative to the floor and is indirectly connected to the seat back support structure by a link that is pivotably coupled to both the second end of the first structural member and the seat back support structure; and wherein the second structural member comprises a first end, and a second end that can move up and down relative to the floor and is pivotably coupled to the seat back support structure; and wherein the first and second structural members are pivotably coupled together at a location between their respective first and second ends;
a fixed support member that is coupled to the floor, and wherein the first end of the first structural member of the scissor mechanism is pivotably coupled to the fixed support member;
a link that is pivotably coupled to both the fixed support member and the first end of the second structural member of the scissor mechanism; and
a seat bottom support member with a first end that is pivotably coupled to the seat bottom at an adjustable angle, and a second end that is pivotably coupled to the scissor mechanism.