FLEXIBLE COLUMNS

• US 3,584,822 A
• Filed: 02/06/1969
• Issued: 06/15/1971
• Est. Priority Date: 02/26/1968
• Status: Expired due to Term

• Current Assignee: John A. Oram
• Original Assignee: John A. Oram
• Inventors: Oram, John A.
• Application Number:
  US04/797,054
• Time in Patent Office: 859 Days
• US Class Current: 248/160
• CPC Class Codes: F16M 11/14 with ball-joint ball-jointed hinges F16C11/06 ; adjustable mountings employing universal joints for lighting devices F21V21/26 - F21V21/30
• CPC Class Codes: F16M 11/40 by means of coilable or bendable legs or spiral shaped legs
• CPC Class Codes: F16M 2200/022 by friction
• CPC Class Codes: F16M 2200/04 Balancing means
• CPC Class Codes: F21V 21/29 employing universal joints
• CPC Class Codes: F21V 21/32 Flexible tubes
• CPC Class Codes: F21V 23/002 Arrangements of cables or conductors inside a lighting device, e.g. means for guiding along parts of the housing or in a pivoting arm

Abstract

A flexible column suitable for supporting apparatus such as electric lamps has a series of ball-and-socket joints rigidly locked together by a tensioned cable, spring means being provided at the free end of the column to tension the cable, together with unlocking mechanism including a lever whereby the spring bias can be opposed to unlock the column.

Claims

1. A flexible column comprising:

a series of ball members, a series of socket members each disposed between associated pairs of ball members to form a series of ball-and-socket joints, seatings provided in the socket members to accommodate said ball members, a tensioned flexible cable threaded through apertures in each ball member and through each socket member to urge said ball members against their said seatings, a termination on said cable, an abutment member abutting said termination, spring means loading said abutment member and tensioning said cable through the abutment between said termination and said abutment member, thereby locking the flexible column, a housing for said spring means, said housing having an aperture therethrough enabling the cable to extend through said housing, and unlocking mechanism operatively associated with said abutment member to counteract, at least in part, the bias provided by said spring means loading said abutment member, whereby operation of said mechanism unlocks the flexible column permitting adjustment thereof.

2. A flexible column as claimed in claim 1 in which the unlocking mechanism includes a lever one end of which engages said abutment member, said lever being arranged to pivot upon a reaction block and urge said abutment member against the spring bias.

3. A flexible column as claimed in claim 2 wherein said lever is of generally U-shape and has, on the ends of its two limbs, two inwardly directed lugs which engage said abutment member, said limbs being cranked adjacent the two lugs to form heels which provide pivotal engagement of said lever with said reaction block.

4. A flexible column as claimed in claim 1, wherein said unlocking mechanism includes a movable lever and a fixed lever, a yieldable plastics member being disposed between said two levers, said movable lever being pivotally disposed between said abutment member and the yieldable member whereby operation of said movable lever causes pivoting of said movable lever against said yieldable member resulting in yielding thereof, said movable lever urging said abutment member against the spring bias during the pivotal movement of said lever.

5. A flexible column as claimed in claim 1, wherein said housing includes an insert providing shoulders within said housing against which one end of said spring means abuts, the opposite end of thereof contacting said abutment member.

6. A flexible column as claimed in claim 1, wherein said spring means biasing said abutment member is a series of Bellville washers disposed, around said cable, within said housing.

7. A flexible column as claimed in claim 1, wherein said socket members have bearing surfaces which are conical and which are covered with a yielding material to increase the friction of said ball-and-socket joints.

8. A flexible column as claimed in claim 1, wherein said yielding material is leather.

9. A flexible column as claimed in claim 1, further including a further termination at the other end of said cable providing an abutment, a U-shaped saddle embracing said cable and abutting said further termination, and means provided to urge said saddle against said further termination, thereby tensioning said cable.

10. A flexible column as claimed in claim 9, wherein said U-shaped saddle is positioned within a base member of the flexible column having an aperture by means of which said cable enters said base member, said base member including a quadrant-shaped guide around which the cable adjacent its further termination bends substantially through a right angle.

11. A flexible column as claimed in claim 10, wherein the said means for urging said saddle against said further termination is a setscrew extending through a threaded bore in said base member, the setscrew carrying a thrust washer which bears against the end of said saddle remote from said termination.

12. A flexible column as claimed in claim 10, wherein said base member includes a clamp for an electric lead in which the insulating sleeve of said lead is deformed by said clamp, said clamp comprising at least three insulating plates each plate having an aperture in which said lead is a close fit, the apertures being staggered relative to one another.

13. A flexible column as claimed in claim 1, wherein the aperture in each ball member, through which said tensioned cable passes, is tapered from each end towards the center of said ball member with the smaller diameter towards the center of the ball member.

14. A flexible column as claimed in claim 13, wherein each ball has a further aperture and an electric lead passes through the further apertures, means being provided on one of said members of each ball-and-socket joint which project into means on the other member of said ball-and-socket joint adapted to limit relative rotation of the said two members about said cable by engagement with said projecting means.

15. A flexible column as claimed in claim 14, wherein said projecting means are pins which project on both sides of the ball member, said means adapted to limit relative rotation of the two members of each ball-and-socket joint comprising arms extending from the inner wall of the socket member and converging upon one another, said pins projecting into the space embraced by said arms.

16. A flexible column as claimed in claim 13, wherein said ball member is part-spherical and has a flange projecting circumferentially therefrom to limit the degree of tilt of said ball member relative to said cable.

17. A flexible column as claimed in claim 13, wherein each ball member of the said ball-and-socket joints has a part spherical portion and two cylindrical portions projecting in opposite directions from said spherical portion into said two socket members associated with each said ball member to limit the degree of tilt of the said ball member relative to said cable by said cylindrical portions contacting the inner surfaces of the said socket members.

18. A flexible column as claimed in claim 17, wherein each ball member has inwardly tapering frustoconical counterbores extending from said cylindrical portions towards the center of said ball member, said counterbores being separated by a wall having tapered apertures therein through which the cable and electric leads are threaded.