Claims
- 1. A chair comprising a base, a central pivot post projecting up from said base and defining a vertical axis of rotation, said base extending 360.degree. around said pivot post, an upright support member spaced radially from said axis, telescopically extendible means coupling said upright support member with said central pivot post for rotation of said upright support member about said axis through an angle of 360.degree. by rotation of said coupling means about said pivot post, and for limited movement of said upright support member toward and away from said central pivot post by telescopic extension or contraction of said coupling means, while maintaining said upright support member in an upright position, said telescopically extendible coupling means comprising two relatively movable parts and antifriction means between said two parts to provide for free movement of said parts relative to one another, a seat mounted at the upper end of said upright member, and single rolling support means at the lower end of said upright support member and rolling on said base upon rotation of said upright support member about said central pivot post and upon movement of said upright support member toward or away from said central pivot post, said rolling support means being capable of rolling in all directions on said base and comprising antifriction bearing means at the lower end of said upright support member to support said upright support member and seat on said base, said upright support member being supported vertically solely by said single rolling support means and being maintained in an upright position by said telescopically extendible coupling means.
- 2. A chair according to claim 1, in which said rolling support means comprises annular antifriction ball bearing means at the lower end of said upright support member with its axis vertical, a single support ball adapted to roll on said base and rotatably engaging said antifriction ball bearing means and means laterally engaging said ball to retain it in alignment with said axis of said antifriction ball bearing means.
- 3. A chair according to claim 1, in which said upright support member comprises a main tubular portion to which said telescopically extendible means is fixed and a tubular stem portion rotatably mounted at the upper end of said main tubular portion and forming an upward extention thereof, said seat being fixed on said stem portion.
- 4. A chair according to claim 3, in which said tubular stem portion has a lower end rotatably received in an upper end portion of said main tubular portion of said upright support member to maintain said stem portion in axial alignment with said main member portion, and in which an antifriction thrust bearing is interposed between said stem portion and said main tubular portion to take the vertical load of said seat.
- 5. A chair according to claim 3, further comprising a back support extending radially and then upwardly from said stem portion and a chair back mounted on an upper end portion of said back support.
- 6. A chair according to claim 5, in which said chair back is mounted on said back support by mounting means providing universal movement of said chair back relative to said back support.
- 7. A chair according to claim 6, in which said mounting means comprises a ball fixed on the back of said chair back, a socket at the upper end of said back support receiving said ball and having a restricted opening to retain said ball in said socket, an antifriction bearing in said socket and spring means in said socket pressing said antifriction bearing against said ball to urge it toward said restricted opening of said socket.
- 8. A chair according to claim 1, in which said telescopically extendible means comprises an arm which is telescopically extendible within predetermined limits for movement of said upright support member and seat toward and away from said axis of rotation.
- 9. A chair according to claim 8, in which said arm comprises an outer portion fixed to said upright support member, an inner portion rotatably supported by said central pivot post, said inner and outer portions of said arm being telescopically movable relative to one another, and antifriction bearing means between said inner and outer portions of said arm providing for longitudinal movement of said arm portions relative to one another while preventing relative rotation of said outer and inner portions.
- 10. A chair according to claim 9, further comprising means for limiting longitudinal movement of said inner and outer portions of said arm relative to one another and spring means acting between said inner and outer portions of said arm throughout their movement within said limits to bias said inner and outer arm portions longitudinally relative to one another.
- 11. A chair according to claim 8, in which said central pivot post comprises a tubular pedestal projecting up from said base and in which said arm has at its inner end a cylindrical portion extending down into and rotatably received in said tubular pedestal.
- 12. A chair according to claim 11, further comprising antifriction bearing means between said pedestal and said cylindrical portion at the inner end of said arm.
- 13. A chair according to claim 1, further comprising a back support extending upwardly from said upright support member to a position above and rearwardly of said seat, a chair back, and means for mounting said chair back on said back support for universal movement of said chair back, said mounting means comprising a ball fixed on the back of said chair back, a socket at the upper end of said back support receiving said ball and having a restricted opening for retaining said ball in said socket, an antifriction bearing in said socket and spring means in said socket pressing said antifriction bearing against said ball to urge it toward said restricted opening of said socket.
- 14. A chair according to claim 13, further comprising a shaft supporting said seat for rotation about a vertical axis, said back support being fixed to said shaft below said seat.
- 15. A chair according to claim 13, in which said antifriction bearing comprises a bearing seat against which said spring means acts and a ball bearing between said seat and said ball fixed to the back of said chair back, said ball bearing comprising a ring of bearing balls and means retaining said bearing balls in a ring.
- 16. A chair according to claim 1, in which said rolling support means comprises a tubular socket on the lower end of said upright support member, said socket having at its lower end a restricted opening, a support ball rotatably received in said socket, said ball projecting partially out through said restricted opening but having a diameter larger than the diameter of said restricted opening so that said ball is retained in said socket, a bearing seat in said socket spaced from said restricted opening, said antifriction bearing means comprising a ball bearing interposed between said bearing seat and said support ball, said bearing seat and ball bearing being positioned to hold said support ball in a position in which it projects partially out through said restricted opening of said socket, said ball bearing comprising a ring of bearing balls and means for retaining said bearing balls in a ring, and means for securing said socket to said upright support member, with said restricted opening downwardly and said support ball resting on said base, said support ball being rotatably supported by said ball bearing for free rotation in all directions.
- 17. A chair according to claim 16, in which said support ball is of hard plastic material.
- 18. A chair according to claim 16, in which an upper end portion of said socket is internally threaded and in which said bearing seat comprises a member which is externally threaded and is screwed into said internally threaded upper end portion of said socket, the resulting threaded interconnection of said socket and bearing seat providing accurate positioning of said support ball with respect to said restricted opening of said socket.
- 19. A chair comprising a circular base plate adapted to rest on a floor and to be movable laterally thereon, a central pivot post projecting up from said base plate and defining a vertical axis of rotation, an upright support column spaced radially from said axis and located near the periphery of said base plate, a telescopically extendible arm connecting said upright support column with said central pivot post for rotation of said arm and upright support column as a unit through an angle of 360.degree. about said vertical axis, a seat mounted at the upper end of said upright support column, and a single rolling support means at the lower end of said upright support column and rolling on said base plate upon rotation of said arm and upright support column about said axis, said arm comprising an outer portion fixed to said upright support column, an inner portion connected with said central pivot post for rotation about said vertical axis but held against rotation about its longitudinal axis and antifriction means between said inner portion and outer portion to provide for free movement of said inner and outer portions relative to one another, said inner and outer portions of said arm being telescopically movable longitudinally relative to one another within predetermined limits for movement of said upright support column and seat toward and away from said axis of rotation but being non-rotatable relative to one another so as to maintain said support column upright, and said rolling support means being rollable in all directions on said base to permit said upright support column and seat to move orbitally about said axis and also to move toward and away from said axis, said upright support column being supported vertically solely by said single rolling support means and being maintained in an upright position by said telescopically extendible arm.
REFERENCE TO PRIOR APPLICATION
This application is a continuation-in-part of my application Ser. No. 893,685, filed Apr. 5, 1978, now abandoned.
US Referenced Citations (9)
Foreign Referenced Citations (1)
Number |
Date |
Country |
260053 |
Jul 1949 |
CHX |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
893685 |
Apr 1978 |
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