CA2265869A1

CA2265869A1 - Wheeled chair with dual pivots

Info

Publication number: CA2265869A1
Application number: CA002265869A
Authority: CA
Inventors: Eugene J. Adamowicz; Michael J. Malis; Jorge A. Nash; Mark B. Greenwald; William G. Mann; James S. Catalano
Original assignee: Individual
Current assignee: MUL Acquisition Corp II
Priority date: 1996-09-12
Filing date: 1997-08-26
Publication date: 1998-03-19
Also published as: WO1998010730A1; AU4092997A; AU732719B2

Abstract

A wheeled chair including a main frame, a pair of large wheels affixed to and supporting the main frame, and a pair of small wheels pivotally mounted to and supporting the main frame. The wheeled chair further comprises a seat frame and an adjustable support device for adjustably supporting a rear portion of the seat frame on a rear portion of the main frame in a plurality of vertical positions. The wheeled chair further comprises a first selectively operable pivot for pivotally supporting a forward portion of the seat frame on a forward portion of the main frame. The wheeled chair further comprises a second selectively operable pivot for pivotally supporting the seat frame on the main frame. The second selectively operable pivot means is located between the forward portion of the seat frame and the rear portion of the seat frame.
The seat frame can thereby be selectively pivoted about one or the other of the first and second selectively operable pivots.

Description

ï»¿10CA 02265869 l999-03- ll1WHEELED CHAIR WITH DUAL PIVOTSTECHNICAL FIELDThe present invention relates to wheeled chairs and, in particular, to wheeled chairs used inhealthcare.BACKGROUND OF THE INVENTIONThere are numerous types of wheeled chairs available for use. For example, the so-called"wheelchair" is widely used and typically includes a pair of large rear wheels which can be operatedby hand by the user of the wheelchair and a pair of small pivoted casters for providing directioncontrol. Typically, prior art wheelchairs have been of a fixed conï¬guration requiring that the userremain seated upright at all times of use.The so-called "ti1t-in-space" wheelchairs have a similar construction to regular wheelchairs,except that a seat frame portion of the chair is pivoted near a rear area of the wheelchair frame, withthe entire seat frame tilting as a rigid unit. In so doing, the upright back portion ofthe seat frametilts backwardly and the normally horizontal seat bottom portion of the seat frame tilts upwardly.An example of such is shown in U.S. Patent No. 4,893,827. One major disadvantage of thisarrangement is that with the seat frame tilted thusly, the userâs feet are swung up and away from thefloor, making it more difficult for the user to move himself around using his feet.Another wheelchair arrangement is the so-called "recliner" in which a tilting back portionof the seat frame is tiltable relative to the seat bottom portion of the seat frame. This has theadvantage of allowing the userâs feet to stay in one position, but at the expense of altering therelationship between the seat back and the seat bottom.Accordingly, it can be seen that a need yet remains for a wheeled chair which can bemanually propelled by hand and which has a seat frame which can be tilted as desired, whileproviding proper support and still allowing the user to self-propel by foot. It is to the provision ofsuch a wheeled chair that the present invention is primarily directed.C 'M'YFILES\lLUZ 14120 Lume\\3LuZ Zvï¬ll) Sub sheen updrsubstitute SheetAMENDED SHEETï»¿U)10f\)YJICA 02265869 l999-03- 11W0 98/ 10730 PCT/U S97/ 150892SUMMARY OF THE INVENTIONBrieï¬y described, in a preferred form the present invention comprises a wheeled chairincluding a main frame, a first pair of wheels afï¬xed to and supporting the main frame, and a secondpair of wheels pivotally mounted to and supporting the main frame. The wheeled chair furthercomprises a seat frame and adjustable support means for adjustably supporting a rear portion of theseat frame on a rear portion of the main frame in a plurality of vertical positions. The wheeled chairfurther comprises a first selectively operable pivot means for pivotally supporting a forward portionof the seat frame on a forward portion of the main frame. The wheeled chair further comprises asecond selectively operable pivot means for pivotally supporting the seat frame on the main frame.The second selectively operable pivot means is located between the forward portion of the seat frameand the rear portion of the seat frame. The seat frame thereby can be selectively pivoted about oneor the other of the first and second selectively operable pivot means.Preferably, the adjustable support means comprises one or more gas springs. Alsopreferably, a trigger means is provided for controlling the operation of the gas springs.Such a wheeled chair according to the present invention has numerous advantages. Forexample, the invention allows the user to self-propel and provides needed support and comfort forlongâterm use. It also is cost effective versus a standard wheelchair with a modiï¬ed seating system.The improved positioning of the seat frame prevents the user from slouching or sliding out of thechair without the use of cumbersome restraints and without changing the relative angle between theseat portion, back portion and leg portions of the seat frame. The invention provides superiorï¬exibility, comfort, and mobility in a single chair design.Accordingly, it is an object of the present invention to provide a wheeled chair which isï¬exible to achieve multiple conï¬gurations.It is another object of the present invention to provide a wheeled chair which allows the userto be tilted and still allows the user to self-propel.It is another object of the present invention to provide a wheeled chair with good comfort,positioning, and transport capabilities, while still providing self-mobility.It is another object of the present invention to provide a wheeled chair which can be tiltedfrom more than one pivot point.ï»¿102025CA 02265869 l999-03- ll3It is another object ofthe present invention to provide a wheeled chair which is durable inits construction and economical in its manufacture.It is another object of the present invention to provide a wheeled chair with improvedpositioning to prevent a user from slouching or sliding out of the chair without the use of restraintsand without changing the relative angle between the seat bottom, back, and leg portions of the seatframe.These and other objects, features and advantages of the present invention will becomeapparent upon reading the following specification in conjunction with the accompanying drawingfigures.BRIEF DESCRIPTION OF THE DRAWING FIGURESFig. l is a schematic, side view of a wheeled chair, according to a preferred form oftheinvention.Fig. 2 is a perspective, partly exploded, schematic illustration ofa portion ofthe wheeledchair of Fig. 1.Fig. 3A is a top view ofa portion ofthe wheeled chair of Fig. 2.Fig. 3B is a top view ofa portion ofthe wheeled chair of Fig. 2 in a modified form.Figs. 4A and 4B show, respectively, the wheeled chair of Fig. l, with a seat frame portionthereof pivoted about a front pivot and shown in an upright position and in a pivoted position,respectively.Fig. 5A and 5B show, respectively, the wheeled chair of Fig. 1, with a seat frame portionthereof pivoted about an intermediate hinge and shown in an upright position and in a pivotedposition, respectively.DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTSReferring now in detail to the drawings, wherein like reference numerals represent like partsthroughout the several views, Fig 1 shows a wheeled chair 10 according to a preferred form of theinvention. The wheeled chair 10 includes a main frame 11 constructed of tubing, as is commonlyknown within the industry.Vsubstitute SheetAMENDED SHELTï»¿CA 02265869 l999-03- ll4A pair of large diameter wheels, such as wheel 12, are attached to and support the rear of themain frame 11. These large wheels are suitable for operation by hand to allow the user of thewheeled chair to roll himself or herself around using his or her hands. A pair of smaller diameterwheels or casters, such as wheel 13, are mounted to the front of the main frame 11. These smaller5 casters are pivotally mounted to the main frame 11 using pivot pins indicated generally at 14. Thepivotally mounted wheels allow the wheeled chair 10 to be moved easily in directions other thanstraight ahead.A seat frame 16 is supported above and secured to the main frame 1 1. At a rear portion 17of the seat frame 16, the seat frame 16 is mounted to and supported above the main frame 11 by a10 gas spring 18. At an upper end of the gas spring 18, the gas spring is attached to the seat frame 16at socket 19. At a lower end of the gas spring 18, the gas spring is secured to the main frame 11 bya lower socket 21. Gas springs are well-known in the art and further explanation of same is notrequired.The seat frame 16 is selectively pivoted to the main frame 11 at a ï¬ont pivot point 23 and15 at an intermediate pivot point 24. The intermediate pivot point is intermediate the front pivot point23 and the rear 17 of the seat frame 16. Preferably, as depicted, the intermediate pivot point ispositioned about oneâthird of the way from the front pivot point 23 toward the rear 17 of the seatï¬ame 16.The seat frame 16 supports a seat back 26 and a seat bottom 27. The seat frame 16 also20 includes handles, such as handle 28. behind the seat back 26. At the front of the seat frame 15,standard wheelchair front riggings 31 are attached thereto. These riggings include conventional legrests and foot rests, etc.As shown in Fig. 1, the height of the main frame 11 above the ground can be varied bymounting the main frame to the rear wheels and the front wheels using different height adjustment25 holes.8 33171366826987 t-BGODVBSOLL 5 l.9:ZZ 3 86-8 -8 5 G0 U3U3U_F}lâl-Vd3: "J:ldW3ï»¿CA 02265869 l999-03- ll5For example, as shown in Fig. 1, the rear wheels 12 can be mounted to the main frame llusing three different positions (as shown, the wheel is mounted using the lowest hole). Similarly,the small casters 13 can be mounted in any one of three positions.Fig. 2 shows a portion of the wheeled chair 10 of Fig. l. Speciï¬cally, Fig. 2 shows, in5 exploded form, a section 36 of tubing making up part of the main frame ll. Also shown is a section37 of tubing of the seat frame 16. As depicted, Fig. 2 shows the front pivot 23 and the intermediatepivot 24. These pivots are comprised of holes or openings formed in the tubing sections 36 and 27for receiving a clevis pin indicated at 38. The clevis pin includes a handle portion 39 and a straightportion 40 which extends through the tubular sections 36 and 37. A look pin or rue pin 42, as is10 well-known in the art, is inserted into the end of the clevis pin and secures the clevis pin in place.The clevis pin is secured to the main frame section 36 using a lanyard 43. As can be quicky graspedfrom viewing Fig. 2, the active pivot point can be changed easily and quickly. For example, theactive pivot point can be switched from pivot 23 to pivot 24 simply by removing the rue pin 42,withdrawing the clevis 38 and inserting the clevis in the intermediate position of pivot 24. The15 clevis pin is then secured in place by reinserting the me pin 42.Preferably, the pivots 23 and 24 are provided with a bushing secured to one or the other ofthe tubular sections 36 and 37. This is best seen in Fig. 3A in which a bushing 44 in the shape ofa washer is shown. The bushing 44 minimizes binding and squealcing between the tubular sections36 and 37.20 If increased load hearing or exemplary durability is desired, the pivots 23 and 24 can bebushed as depicted in Fig. 3B. As shown therein, the tubular sections 36 and 37 are provided withbushing extending completely through the tubes and having ï¬anges 46, 47 which face one another.The ï¬anges provide a good wear surface, similar to the function of the bushing 44. Meanwhile, thelength of the through bushings spreads out the load borne on the clevis pin 3 8, thereby reducing wear25 and allowing the clevis pin to carry a greater mechanical load.Referring now to Fig. 4A, this ï¬gure shows the seat frame 16 in an upright position, with theseat frame being pivoted about the front pivot 23.'0 #!L7L868â¬Z686l7 l-8600786011. 5 89:22 5 96-6 -9 2 90 U3Ll3Ul]lâl-\'/d3: 'EHdW3ï»¿102593! l.7L886â¬Z896VCA 02265869 l999-03- ll6The tilted position ("wedged" position) is shown in Fig. 4B. In this way, the user of thewheeled chair is pivoted about pivot 23. This pivot coincides roughly with the back of the user'sknee, thereby keeping the knee in roughly the same position relative to the ground. This allows theusers feet to still reach the ground by straddling the riggings 31. Alternatively, the riggings can belowered, swung away, or removed to assist this effort.. On the other hand, the wheeled chair 10 can be operated to pivot the seat frame 16 about theintermediate pivot point 23, as depicted in Fig. 5A. One can tilt or pivot the entire seat frame 16about the intermediate pivot 23 to achieve the tilted orientation shown in Fig. 5B. When tilting theseat frame 16 to the tilted orientation shown in Fig. SB, the knees of the user will be swung upwardlyaway from the ground along with the front of the seat frame 16.While the invention has been disclosed in preferred forms, it will be apparent to those skilledin the art that many modiï¬cations, additions, and deletions may be made therein. These and othermodiï¬cations, additions, and deletions nevertheless fall within the scope of the following claims.C:\M'YF lLÂ£S\lumca.demI.daser.wpd0-QSOOVQSOLL 5 99:22 3 86-6 -9 590 U3U3U[l_W-Vd3: '9JdW3

Claims

What is claimed is:

1. A wheeled chair comprising a main frame (11), a first pair of wheels (12) supporting the main frame, a second pair of wheels (13) each pivotally mounted to and supporting the main frame, and a seat frame (16), and characterized in that means are provided for selectively mounting the seat frame to the mainframe for pivotal movement at a first position (23) and at a second position (24), with the second position being between the first position and a rear portion of the seat frame.

2. A wheeled chair as claimed in Claim 1 further characterized in that the means for selectively mounting comprises a first selectively operable pivot means for pivotally supporting a forward portion of the seat frame and a second selectively operable pivot means for pivotally supporting the seat frame on the main frame.

3. A wheeled chair as claimed in Claim 1 or Claim 2 further characterized in that the first and second pivot means comprise pivot openings formed in the seat frame and in the main frame and removable pivot pins (38) for engagement with the pivot openings.

4. A wheeled chair as claimed in any preceding Claim further characterized in that the means for selectively mounting a seat frame (16) to the main frame (11) includes adjustable support means for adjustably supporting a rear portion of the seat frame on a rear portion of the main frame in a plurality of vertical positions.

5. A wheeled chair as claimed in Claim 1 further characterized in that the means for selectively mounting the seat frame to the main frame further includes a first selectively operable pivot means (23) for pivotally supporting a forward portion of the seat frame on a forward portion of the main frame and a second selectively operable pivot means (24) for pivotally supporting the seat frame on the main frame, with the second selectively operable pivot means being located between the forward portion of the seat frame and the rear portion of the seat frame.

6. A wheeled chair as claimed in Claim 4 or Claim 5 further characterized in that the adjustable support means includes at least one gas spring (18).

7. A wheeled chair as claimed in Claim 6 further characterized in that control means (22) are provided for controlling operation of the at least one gas spring (18).

8. A wheeled chair as claimed in any of Claims 5-7 further characterized in that the first and second pivot means comprise pivot openings formed in the seat frame (16, 37) and in the main frame (11, 36) and removable pivot pins (38) for engagement with the pivot openings.

9. A wheeled chair as claimed in any of the preceding claims further characterized in that the first pair of wheels (12) are larger than the second pair of wheels (13).