Adjustable support attachment for wheelchairs

The present invention is an adjustable support attachment for wheelchairs having vertical or horizontal arm rest members. The support, which is intended to position articles and devices within variable and convenient access to the occupant of the chair, is attached to the arm rest member by means of a mounting base, to which one end of a base tube is releasably and rotatably swivel-mounted. On the other end of the base tube is fixed an adjustable friction joint allowing angular positioning of a lower arm tube in a vertical plane. An adjustable pivoting friction joint on the radially outer end of the lower arm tube allows fully circular positioning throughout a plane perpendicular to the lower arm, in combination with an adjustable friction joint, integral with the pivotal joint, which allows angular positioning of an upper arm member within the rotatable plane including the lower arm. A releasably telescoping rod allows extension of the upper arm in discrete adjustments and an adjustable friction joint fixed at the radially outer end of the rod allows angular tilting positioning of a mounting head within the rotatable plane including the upper arm. The mounting head includes a facing plate perpendicular to the longitudinal axis of the head and a threaded mounting stud perpendicular to the plate.

BACKGROUND OF THE INVENTION 
The present invention relates to article support attachments for 
wheelchairs and in particular to a support which can be readily adjusted 
throughout the proximity of the occupant. 
Numerous attachments have been developed which aid the person in a 
wheelchair. Among these are devices which attach to the arm rest or frame 
member tubing, such as trays, receptacles, and supports. The trays are 
generally at arm rest level, such as in U.S. Pat. No. 3,215,467, entitled 
Retractable Attachment For Chair Arms, issued to W. McFarland et al. on 
Nov. 2, 1965, and as in U.S. Pat. No. 3,870,362, entitled Tray Attachment 
For Wheelchairs, issued to Richard L. Large on Mar. 11, 1975, and as in 
U.S. Pat. No. 3,522,887, entitled Support For a Paraplegic Wheel Chair, 
issued to Edward A. Petersen on Aug. 4, 1970. These trays are fixed in 
vertical and angular position and are not intended to provide fastening 
support to articles. The receptacles are also generally at arm rest level, 
and are of limited adjustability, such as in U.S. Pat. No. 3,759,569, 
entitled Receptacle Attachment For Wheelchair Arm, issued to Lester H. 
Bennet on Sept. 18, 1973, and as in U.S. Pat. No. 4,158,428, entitled Drop 
On Lift Off Basket Assembly For a Wheelchair, issued to Clarence W. Bates 
on June 19, 1979. These receptacles are essentially fixed in vertical, 
horizontal, and angular position and provide passive enclosure rather than 
fastening support to articles. Other supports are more adjustable but of a 
single or specialized application, such as in U.S. Pat. No. 3,170,665, 
entitled Easy Drinker Device, issued to Mary G. S. Ryan on Feb. 23, 1965, 
and as in U.S. Pat. No. 3,730,589, entitled Head or Back Support For 
Wheelchair, issued to Buddy F. Lane on May 1, 1973. These supports are 
adjustable in several directions but are intended to provide a particular 
support function rather than a generalized mounting for various articles. 
None of these patents describe or anticipate a wheelchair attachment which 
is fully adjustable in vertical, horizontal, and angular directions 
throughout the arm length proximity of the occupant and which provides 
fastening support to light and medium weight articles of different types. 
The need for an adjustable generalized fastening support attachment exists 
because many persons in wheelchairs have sufficient use of their arms and 
hands to manipulate articles or operate devices within reach, and to 
adjust an easily positioned support of such articles or devices. 
SUMMARY OF THE INVENTION 
An adjustable support attachment for wheelchairs constructed according to 
the present invention comprises a mounting base attached to the 
wheelchair, a base tube releasably and rotatably swivel-mounted thereon 
which is fixed to an adjustable friction joint allowing the angular 
positioning of a lower arm tube in a vertical plane, an adjustable 
pivoting friction joint on the radially outer end of the lower arm tube 
allowing fully circular positioning throughout a plane perpendicular to 
said lower arm, in combination with an adjustable friction joint, integral 
with the pivotal joint, which allows angular positioning of an upper arm 
member within the rotatable plane including said lower arm, a releasably 
telescoping rod allowing extension of the upper arm in discrete 
adjustments, an adjustable friction joint fixed at the radially outer end 
of said rod allowing angular tilting positioning of a mounting head within 
the rotatable plane including said upper arm, said mounting head including 
a facing plate perpendicular to the longitudinal axis of the head and a 
threaded mounting stud perpendicular to said plate. 
A general object of the present invention is to provide a wheelchair 
support accessory which mounts readily on standard design wheelchairs, 
enables the occupant with limited manual ability to position, adjust, and 
secure the support virtually throughout the space within his manual 
proximity, and allows the occupant to fasten thereon and operate, 
manipulate, or otherwise use various articles and devices which have been 
equipped with standard threaded stud fittings. 
A specific object of the present invention is to provide a wheelchair 
support accessory which is adjustable about its fixed base rotationally, 
vertically up or down, horizontally in all lateral directions, and 
angularly throughout nearly all solid angle directions by means of 
lever-advantaged forces and friction joints. 
A further specific object of the present invention is to provide a 
wheelchair support accessory which allows adjustment near the mounting 
head comprising longitudinal extension and contraction by means of a 
leveraged pin-lock, angular tilting of the mounting head, and 
interchanging various threaded stud fastening means. 
A major advantage of the present invention over the prior art is that it 
allows the person in a wheelchair to use many articles not otherwise 
accessible to him without the air of an attendant or without specially 
designed or improvised supports which are particular to each type of 
article. 
A further advantage of the present invention over the prior art is that, 
due to its highly generalized positioning characteristics, it can be 
readily collapsed into a compact form when not in use and either stored 
temporarily on the outside of the chair arm rest without interfering with 
the normal use of the wheelchair, or it may be easily removed from the 
base mount for separate storage. 
Objects and advantages other than those set forth above will be apparent 
from the following description when read in connection with the 
accompanying drawings of a preferred embodiment, whose novel features are 
set forth with particularity in the appended claims.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawing, like reference numerals in the figures designate 
like parts. In FIG. 1 reference numeral 10 designates a portion of a 
conventional wheelchair arm rest, comprising of metal tubular stock. The 
embodiment of the present invention which has been illustrated is mounted 
on the horizontal portion of the arm rest, although alternatively a 
vertical portion could be used, or also some other convenient side frame 
member of the wheelchair, by suitble orientation of the members of the 
present support. 
Mounted on said arm rest 10 by means of a clamping strap 12 is a mounting 
base 11 shaped to enclose partially the arm rest 10 opposite said strap 12 
fastened by releasable means such as machine screws. The base 11 receives 
a base swivel tube 13 such that said tube 13 turns readily about its 
longitudinal axis until releasably fixed by means of the long-handled set 
screw 14. The components including said base 11, tube 13, and screw 14 
comprise a base swivel joint. 
Said base tube 13 extends vertically upwardly and is received and fixably 
fastened, as by nut and bolt, to a rectangular coupling block 15 to which 
is also fixably fastened parallel and opposing identical lower arm 
friction plates 16 which extend vertically upwardly and terminate in a 
generally circular coaxial configuration perpendicular to the axis of the 
base tube 13. Positioned in contact between and coaxial with said friction 
plates 16 is a circularly cylindrical lower arm friction disc 17 which 
rotates readily about its axis until releasably fixed by compressional 
friction between its circular faces and those of the friction plates 16 by 
means of a lower arm friction adjustment fastener 18, such as a nut and 
bolt, along the common axis of the disc 17 and plates 16. The disc 17 
receives and is fixably fastened to a lower arm tube 19 positioned 
perpendicularly to and extending radially outwardly from said common axis. 
The components including said tube 13, block 15, plates 16, disc 17, tube 
19 and fastener 18 comprise a lower arm friction joint. 
The radially outermost end of the lower arm tube 19 is received by and 
releasably and frictionally fastened to a rectangular pivot friction block 
20, which is segmented in halves along a plane through the axis of the 
lower arm tube 19 in such a manner as to provide clamping means on tube 19 
using tightening adjustment of a pivot friction fastener 21, such as a nut 
and bolt, positioned perpendicular to and offset from the axis of the 
lower arm tube 19. Retention collars 22, fixably fastened on the lower arm 
tube 19 in rotating contact with either side of said block 20, prevent 
longitudinal movement and provide further pivotal friction. 
Fixed to said block 20, by suitable fastening means such as machine screws, 
are a pair of parallel and opposing identical upper arm friction plates 
23, positioned perpendicular to the axis of the lower arm tube 19 and 
parallel to said plane segmenting block 20. Similarly to plates 16, the 
upper arm friction plates 23 terminate in a generally circular coaxial 
congifuration in facing contact with and enclosing a circularly 
cylindrical upper arm friction disc 24, which rotates readily about its 
axis until releasably fixed by compressional friction between its circular 
faces and those of the friction plates 23 by means of an upper arm 
friction adjustment fastener 25, such as a nut and bolt, along the common 
axis of the disc 24 and plates 23. The disc 24 receives and is fixably 
fastened to an upper arm tube 26 positioned perpendicularly to and 
extending radially outwardly from said common axis. The components 
including said tube 19, block 20, fastener 21, collars 22, plates 23, disc 
24, fastener 25, and tube 26 comprise an upper arm friction joint. 
The radially outermost end of the upper arm tube 26 is received by and 
fixably fastened to a coupling collar 27. Referring to FIG. 2 and FIG. 3, 
said tube 26 receives parallel to its axis a key 28 which is fastened, as 
by a machine screw, to the coupling collar 27 within a collar keyway slot 
29. An extension arm rod 30 is slidably and telescopingly received 
internally by said tube 26 such that a portion of key 28 internal to tube 
26 is slidably received within a rod keyway slot 31 parallel to the axis 
of and extending along the length of said rod 30. Said keyway slot extends 
near but not through the ends of said rod 30, providing a limit stop to 
the sliding motion of said rod 30. 
Integral with coupling collar 27 and extending along said tube 26 is a 
lever housing 32 to which is rotatably fastened an extension arm release 
lever 33 by means of a lever fulcrum pin 34. An engaging spring 35 between 
said housing 32 and release lever 33 retains locking pin 36 in receiving 
position through tube 26 into one of a plurality of locking holes 37 in 
and distributed along the length of said rod 30. The components including 
said tube 26, collar 27, key 28, rod 30, lever 33, pin 34, spring 35, and 
locking pin 36 comprise an upper arm extension coupling joint. 
Referring back to FIG. 1, the end of said rod 30 extending longitudinally 
away from and external to said tube 26 is received by and fixably fastened 
to a circularly cylindrical mounting head friction disc 38, such that the 
axis of said disc 38 is perpendicular to the axis of said rod 30. Said 
disc 38 is in facing contact with and enclosed by a portion of a pair of 
parallel and opposing identical mounting head friction plates 39 of 
generally circular coaxial configuration similar to those of plates 23 and 
16, such that plates 39 rotate readily with respect to said disc 38 about 
their common axis until releasably fixed by compressional friction between 
their circular faces and those of said disc 38 by means of a mounting head 
friction adjustment fastener 40, such as a nut and bolt, along said common 
axis of said disc 38 and plates 39. 
Said plates 39 extend radially outward from and perpendicularly to said 
common axis and form a generally rectangular terminus enclosing and 
fixably fastened to a generally rectangular mounting head block 41 on 
which is fixably fastened a generally circular mounting face plate 42 such 
that the facing plane of said plate 42 is perpendicular to the 
longitudinal axes of said plates 39 and parallel to the common axis of 
said disc 38 and the generally circular portions of said plates 39. An 
outwardly projecting threaded mounting stud bolt 43 is fastened into the 
center of and perpendicular to said face plate 42. The components 
including said rod 30, disc 38, plates 39, fastener 40, block 41, face 
plate 42, and stud 43 comprise a mounting head friction joint. 
The tube, plate, rod, block, and collar stock as described heretofore is 
preferably of aluminum or its alloys except where steel stock is more 
suitable such as for the base clamping strap 12, base tube 13, lever arm 
set screw 14, key 28, release lever 33, locking pin 36, and mounting head 
face plate 42, as well as all fasteners. However, other suitable materials 
can be substituted within the scope of the present invention. 
The adjustable support attachment for wheelchairs as heretofore described 
provides a mounting for a multiplicity of articles and devices, which have 
been or are capable of being equipped with standard threaded mountings and 
couplings, such as cameras, flash and spot lighting equipment; electronic 
consumer or specialized devices such as tape recorders, radios, 
microphones, and remote control switches; trays, tables, or holders for 
books, writing and craft materials, and art works; rifles and other 
sporting equipment; and various other light or medium weight objects which 
can be supported by a threaded mount. 
To position the mounting face plate 42 and stud 43 in virtually any 
location within the manually accessible proximity to a wheelchair 
occupant, the swiveling, pivoting, rotating, and extending degrees of 
freedom of the present invention are readily manipulated by means of 
leverage forces. All four friction joints can be tightened in final 
position by means of a single size wrench when all joint fasteners 18, 21, 
25, and 40 are comprised of the same size nut and bolt. 
The swivel position of the base tube 13 is easily adjusted and tightened by 
means of the lever arm set screw 14 to allow horizontal orientation of the 
lower arm 19 throughout a full circle of arc. The lower arm 19 can be 
rotated throughout approximately three-quarters of a full circle within 
any plane through the base tube 13, allowing vertical and angular 
orientation of the lowermost end of the upper arm 26. The uppermost end of 
the upper arm 26 can be pivoted throughout a full circle of arc about the 
axis of the lower arm 19, and can also be rotated throughout approximately 
a half-circle of arc within any plane defined by the axis of the lower arm 
19 and the axis of the upper arm 26. 
The upper arm telescoping rod 30 is easily lengthened or shortened in 
longitudinal extension by means of the long-handled release lever 33. The 
extension arm keyway slot 31 terminates near but does not pass through the 
end of said rod 30 internal to the upper arm tube 26, hence precluding an 
inadvertent separation of said rod 30 and said tube 26 during an extension 
adjustment. The mounting head face plate 42 can be rotated in final 
tilting adjustment throughout approximately three-quarters circle of arc 
within any plane defined by the axis of the lower arm 19 and the axis of 
the upper arm 26. The stud bolt 43 is preferably a standard quarter 
inch--twenty threads per inch mounting, which allows direct coupling to 
articles or devices as well as indirect coupling such as by means of 
adapters to other thread sizes or fasteners, standard ball-joint mounts, 
and other suitable brackets or surfaces capable of mounting, holding, or 
otherwise retaining articles and devices. 
When not in use, the present invention can be easily removed either by 
unfastening the clamping strap 12 and removing the mounting base 11, or by 
unfastening the lever set screw 14 and decoupling the base tube 13 from 
the mounting base 11, which can be retained attached to the arm rest 10. 
The support can be compactly collapsed for storage, whether attached or 
removed, into a generally parallel configuration of the base tube, lower 
arm, and upper arm. 
While the above description contains many specificities, these should not 
be construed as limitations on the scope of the invention, but rather as 
an exemplification of one preferred embodiment thereof. Many other 
variations are possible, for example different combinations of materials, 
lengths, thicknesses, and diameters of tubes, rods, discs, and plates, or 
of alternate friction surfaces and bushings, or of various fasteners such 
as wing-nuts or otherwise handle-leveraged tighteners. Accordingly, the 
scope of the invention should be determined not by the embodiment 
illustrated, but by the appended claims and their legal equivalents.