A wheelchair with the ability to become narrower for transportation and storage has several benefits. It allows the wheelchair to fit into a vehicle easier without the need to remove components, such as wheels. It takes less room to store when not in use. When folded it will fit through narrow passageways. However, traditional folding wheelchairs suffer from several problems.
As non-limiting examples, a typical folding wheelchair with an X-frame style frame, as can be seen in U.S. Pat. Nos. 2,379,566 and 5,328,183, folds very compactly but at the expense of functionality and durability. Other designs fold the frame vertically, as can be seen in U.S. Pat. No. 5,593,173, or laterally, as can be seen in U.S. Pat. Nos. 4,863,181; 6,572,133 and 4,595,212. All of the folding methods require many additional components adding substantial weight and complexity. The added weight makes it much more difficult to self propel and to lift into a vehicle for transport. Due to the many joints and pivots, they also have reduced durability for daily use requiring frequent maintenance. The additional components also increase the cost of manufacture.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
A foldable frame for a wheelchair is provided. The foldable frame includes first and second side frames and a frame structure connecting the first side frame to the second side frame. The frame structure permitting the first side frame and the second frame to selectively move toward each other and away from each other.
The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
The foregoing aspects and many of the attendant advantages of this invention will become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
A foldable wheelchair constructed, in accordance with one embodiment of the present disclosure, may be best understood by referring to
As may be best seen by referring to
Referring to
As may best be seen by referring to
The interconnecting tube assemblies include the two outer sleeve tubes 13. The forward tube passes through and is welded to side frame 11 and the second passes through and is welded to backrest support tube 12. Additionally, there are two inner sleeve tubes 23. The forward inner sleeve tube 23 passes through and is welded to side frame 21 and the second passes through and is welded to backrest support tube 22. The inner sleeve tube is of proper outside diameter to fit inside the outer sleeve tube 13 with sufficient clearance to not bind up, but similar enough to allow the outer sleeve tube 13 to be securely clamped around it using clamping assembly 40.
As may be best seen by referring to
The clamping assembly works in two ways to lock the inner sleeve tube 23 to the outer sleeve tube 13 when the wheelchair is in its open position. The first way the inner and outer sleeve tubes 23, 13 are locked together is with a barrel lock. The barrel lock has an open and a locked position. When the barrel lock is in the open position (
Referring to
A foldable wheelchair of the present disclosure includes a set of large rear wheels, a set of front smaller wheels or casters. The wheels are connected to two generally vertical side frames between which extends interconnecting frame structures connecting the two side frames together. The interconnecting frame structures connect the first side frame to the second side frame in a manner permitting the first frame member and the second frame member to be selectively moved toward and away from each other, thereby, permitting the collapse of the wheelchair for storage or transport. The interconnecting structure includes a sliding joint. In its preferred form, it would have two telescopic cross tubes. One telescopic tube connects the forward end of the side frames and the second connects the aft end of the side frames. The telescopic tubes include an outer tube fixed to one side frame and a slidable inner tube fixed to the other side frame. The inner and outer tubes can be locked together to form a rigid frame. The locking mechanism can be readily changed from the locked open wheelchair position to an unlocked position that allows the wheelchair to be folded.
The sliding interconnecting structure provides a robust and simple folding mechanism. With fewer components and no pivoting joints the system provides a durable, lightweight and lower cost folding system.
While illustrative embodiments have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.
This application is a continuation of patent application Ser. No. 11/760,625, filed on Jun. 8, 2007, which claims the benefit of Provisional Application No. 60/812,582, filed Jun. 8, 2006, the disclosure of which is hereby expressly incorporated by reference.
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Number | Date | Country | |
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20090194974 A1 | Aug 2009 | US |
Number | Date | Country | |
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60812582 | Jun 2006 | US |
Number | Date | Country | |
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Parent | 11760625 | Jun 2007 | US |
Child | 12244691 | US |