Field of Invention. This application is directed to a mobile device for persons with limited ambulatory ability. Such patients present mobility and ambulatory problems to themselves, to hospital and clinic technicians and to the personnel of senior living and assisted care facilities. Such problems include difficulty of moving from a bed to a mobile wheelchair and then to an imaging center where they must stand or position themselves on a table for an X-ray, computed tomography scan (CT scan) or a magnetic resonance image (MRI). Similarly, in senior living facilities and assisted living facilities, patients must often be moved from beds to shower facilities and to food service facilities.
These mobility problems are very trying to the patient. In addition, they impose substantial costs upon care providers in that additional personnel must be engaged to assist such patients to meet their mobility requirements. Too, such mobility problems also impose extra time costs in facilitating such movement.
Description of Related Art. These mobility problems have been previously recognized. Indeed, there have been numerous efforts to provide an acceptable, commercial solution to these problems. In general, those efforts have included a wheelchair for mobility combined with a power lift to assist the patient to move from a sitting position in the wheel chair to a standing position. However, such prior devices are illustrated by expensive, complex systems that often included a plurality of linkages, cables, pulleys, etc. An example of such systems is disclosed in U.S. Pat. No. 7,165,778 which issued on Jan. 23, 2007 on an application of Todd A. Kuiken. That effort to combine a sit-to-stand feature with a wheel chair feature required a plurality of linkages, anti-tip wheels, and a manually operated ratchet drive which manipulates tubes, a pulley and a cable system on each side of the wheel chair.
Another effort to design a wheel chair having a sit-to-stand function is disclosed in U.S. Pat. No. 5,772,226 which issued to Bobichon on Jun. 30, 1998. Again, this effort comprises a substantial number of linkages with an actuator that pivots the seat counterclockwise to assist the patient to move from a sitting to a standing position.
Such efforts to provide a wheelchair with a sit to stand capability also includes a separate lift system which can be combined with a standard wheelchair. This separate lift system requires a “universal attachment mechanism” that is adapted to attach to the frame of the wheel chair to raise and lower the wheelchair between an elevated position assisting the patient to stand and a mobile position. This prior patent is U.S. Pat. No. 9,333,132 which issued to Katezlift of Mendota Minn. on May 10, 2016.
On belief, none of the prior art developments have resulted in a commercially acceptable mobile wheelchair with a sit-to-stand capability. Those developments appear to lack the desirable low cost, as well as the simplicity, strength and/or reliability to be commercially acceptable. In sum and substance, the development of an acceptable, commercial sit-to-stand wheelchair has been a recognized long felt need.
Contrary to the prior art, the present inventions avoid the use of plurality of linkages and pivot points moving through various angles to elevate the patient to a standing position. Instead, the present inventions comprise a low cost, high strength sit-to-stand wheel chair assembly. Their simplicity, strength and low cost is, in part, based on a telescopic power actuator that, of itself, comprises the wheelchair frame so as to avoid the duplication of both a separate frame and a separate power actuator. Moreover, this simplicity, strength and low cost structure includes a simple, low cost operative movement with a power actuator that is, preferably, encapsulated within the telescopic members.
Simplicity and low cost is further achieved by mounting and/or linking the wheels to the upper telescopic member so as to move the wheelchair from a retracted mobile position in which the wheels support the patient to an extended position in which the wheels are elevated and then to a solid base is positioned on the surface or ground to move the patient to a standing position with solid support and with confidence.
To achieve this structure and its unique functional capability, the present inventions are designed to provide one or more of the following advantages and characteristics:
1) a simple design in which an integrated actuator system moves the chair from a wheel supporting position to a fixed, floor supporting position when it is desired to assist the patient to move from a mobile, sitting position to a standing position;
2) a simple low cost design using tubular members to provide substantial strength and rigidity to the unit;
3) a simple low cost design using extendable, telescopic, tubular members integrated with a linear actuator to raise and lower the person from a wheel chair sitting position to an elevated sit-to-stand position;
4) a design using guided telescopic members to eliminate the undesirable lateral movement that results from a plurality of pivot points and interconnecting linkages upon elevating a patient;
5) a sit-to-stand wheelchair that eliminates the need for wheel brakes, and provides solid floor surface support for the base of the chair when elevating a patient to a standing position;
6) a sit-to-stand wheel chair that raises the patient to a standing position and simultaneously lowers the entire assembly to a supporting floor to provide a rigid, sturdy foundation to provide patient confidence with the certainty of movement;
7) a sit-to-stand wheelchair in which power is supplied in the form of a power linear actuator, preferably positioned within the telescopic members;
8) a sit-to-stand wheelchair in which the front wheels of the wheelchair are are moved to and from a mobile position by the power actuator that also controls vertical movement of the chair; and
9) an integral, unified mobile lift wheelchair having a low cost, high strength design with a minimum number of parts.
The manner in which the foregoing objectives and characteristics are attained is disclosed in the following specification and drawings in which:
The preferred embodiments of my wheel chair inventions are shown in the drawings identified above. To illustrate the various alternative design variations of the present invention and the numerous modifications that may exists, three different wheelchair species are illustrated in the drawings. Each design incorporates telescopic or relative extendable-retractable members to move the chair from a mobile position to a stationary position in which the patient is elevated to a standing position. In the mobile position, the wheelchair has the normal functions expected of a wheelchair. In the elevated position, the patient is moved vertically upward or forwardly and upward to further assist his/her exit from the chair and subsequent movement to a standing position.
A first design is depicted in
The wheel chair seat 26 is fixedly mounted upon the two upper telescopic members 20 through seat plates 22 affixed thereto. Preferably, the seat 26 has a seat back 28 and a seat bottom 30. The seat bottom 30, is preferably, a one piece unit, which is, in itself, more than adequate to enable a person to move from a sitting position to a standing position. However, an alternative is a two piece design for the seat bottom 30 such as that disclosed in a U.S. Pat. No. 8,973,997, filed as Application Ser. No. 13/185,855, the entire contents of which are incorporated herein as if they were also contained herein. Another alternative would be to provide for limited pivotal movement of the seat bottom 30 to further assist the person to move from the sitting position to the standing position.
The wheelchair can be converted from the mobile position of
As shown in the embodiment of
Clockwise or counterclockwise rotation of the shaft 42 is caused by prepackaged gear drives 46 mounted on the underneath side of the seat with a battery package 48 (see
Also mounted on the upper telescopic members 20 are large wheels 32 which have an axle 35 passing through a bracket 34 which is mounted on extension 20. (See
Persons skilled in the art will appreciate that different types of linear actuators can be used, including, for example, hydraulic actuators and/or hydraulic cylinders with electric fluid pumps.
In addition to moving the main wheels 32 up and down, the unit is provided with front wheels 60 which are also raised and lowered with respect to base 12 upon actuation of the linear actuator assembly 40. These wheels may fixed for straight travel or alternatively, they may comprise casters, balls or other wheels that permit rotational movement in any direction.
Considering the front wheel embodiment of
This rotation of the front wheels 60 to engage the surface 11 occurs simultaneously with the rear (main) wheels 32 engaging the surface 11. (As is common practice with patent drawings, these drawings, including the bellcrank and the remaining drawings are not to scale, and the dimensions and extent of movement will vary depending upon the size of the wheels, the height to which the wheel chair is raised, etc).
Alternatively, and as shown in
A second embodiment of the front wheel system is the caster system 64 shown in
A third embodiment of these inventions is reflected in
As best illustrated in
The clamp assembly 123 may include the seat bracket or plate 140 attached to the clamp 126 by its depending flanges 142. This bracket 140 carries a seat bottom 144 having a seat back 146. In addition, the clamp 124 is also provided with an aperture 150 for receiving the axle 152 of the rear wheels 154 of the wheelchair which may include a manual push ring 156.
As those skilled in the art will appreciate, the clamp assembly combination 123, comprising the clamp 124, the seat 144 and its bracket 140 together with the wheels 154, provides a very desirable, strong, low cost operating assembly. For example, operation of the linear actuator 114 in one direction will cause the telescopic member 118 to move vertically upward, carrying with it the seat 144, a person (not disclosed), and the wheels 154. This vertical upward movement of some 10-15 inches (depending on the actuator selected) will assist the ambulatory person to move to a standing position while minimizing the muscular effort to raise his/her own weight. And, significantly, as the clamp assembly 123 moves the wheels 154 and the person upward, the base members 112 are lowered to the surface to provide a very stable support for the wheelchair and to provide confidence of stability to the ambulatory person.
Alternatively, downward telescopic movement of the linear actuator 114 results in engagement of the rear wheels 154 to provide mobility to the wheelchair person. However, such mobility also requires engagement of the front caster wheels 170 with the surface. These front casters 179 are also actuated by a telescopic linkages 172 similar to those of
In operation, as the linear actuator 114 is lowered, the clamp assembly 123 lowers the seat 144 and causes the main wheels 154 to engage the surface. This lowering movement of the seat 144 also causes the upper cylinder 174 for the front caster wheels 170 to engage the abutment ring or lock 178 that is welded or affixed to the lower link 176 which, in turn, causes the linkage 180 to move the casters 170 into engagement with the surface to provide four wheel mobility to the wheelchair.
As noted earlier, expansion or upper telescopic movement of the linear actuator 114 raises the seat 114 and the rear wheels 154 some 10-15 inches and simultaneously lower the base supports 112 to the surface. This upper telescopic movement also removes the force exerted on the casters 170 by pulling the upper cylinders 172 away from the abutment 178 thereby permitting the base members 112 to engage the surface for stability of the wheelchair.
Persons skilled in the art will also appreciate that numerous choices can be made regarding wheel sizes, tubular sizes, the extend of movement of the upper telescopic members etc. For this reason, and consistent with the Patent Office rules, the drawings presented herein are not to scale. In addition to changes in sizes, various alternative types of actuators may be used, including hydraulic as well as manual. Significantly, those skilled in the art will appreciate that using the linear actuator as the frame will support various modifications and alternatives. As an example, the frame might be mounted on an axle that is provided with a brake in order to provide a stationary platform for using the actuator to raise the person to the standing position. Too, person skilled in art will appreciate the modification of the linkages and the abutment surfaces may be readily changed without departing from the scope of the inventions presented herein. Additionally, foot rest plates may be added to make the wheelchair more comfortable. The electronic circuit for actuation of the linear actuators may vary depending on numerous safety features such as sensors to limit the height of the movement of the actuators, control boxes that are chosen etc.
This is a non-provisional U.S. Patent Application which claims the benefit of Provisional Application No. 62/707,595 entitled SIT-TO-STAND WHEELCHAIR filed Nov. 9, 2017, the entirety of which is incorporated in this application as if fully set forth herein.
Number | Date | Country | |
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62707596 | Nov 2017 | US |