WO2019022676A1

WO2019022676A1 - Safe-walker

Info

Publication number: WO2019022676A1
Application number: PCT/SG2018/050386
Authority: WO
Inventors: Krishnamurthy Natarajan
Original assignee: Krishnamurthy Natarajan
Priority date: 2017-07-28
Filing date: 2018-07-30
Publication date: 2019-01-31
Also published as: SG11201907193TA

Abstract

The present invention describes a safe-walker, which is functionally a combination of a wheel-chair (WC) and a walker, with fall prevention support frame (SF) integral with a seat movement (SM) mechanism to enable a user, at least, to walk or to stand upright. The seat movement (SM) mechanism includes a pair of substantially L-shaped roller tracks (RT) with grooves within which rollers carrying seat slats (WP) move back or forth to take up either (i) seat in place (AB), or (ii) seat moved-away (BD) to give space and to allow the user to walk within that space. The seat movement (SM) is automatically operated by a linkage (EF) when the person stands up or sits down. The safe-walker is fail-safe because if the automated seat movement (SM) does not work, the user is still supported by a chest harness (CH) connected to the support frame (SF). The safe-walker is foldable.

Description

SA F E -WA L K E R

Related Application

[001 ] The present i nvention claims priority to Singapore patent application no. 10201706161X fi led on 28 J uly 2017, the disclosure of which is incorporated in its entirety.

Field of Invention

[002] The present i nvention relates to a safe-wal ker, whi ch is a wheel-chair and a walker combination and is equipped with some safety and conveni ence features.

Background

[003] There are many innovations in walking aids for physically challenged users. Despite these i nnovati ons, there i s sti 11 a need to provi de a saf e-wal ker; advantages of the saf e-wal ker will be appreciated after this device has been described.

Summary

[004] The following presents a simplified summary to provide a basic understanding of the present invention. This summary is not an extensive overview of the invention and is not intended to identify key features of the invention. Rather, it is to present some of the inventive concepts of this i nvention in a generalized form as a prelude to the detailed descri pti on that i s to f ol I ow.

[005] The present invention seeks to provide a safe-walker, which is a wheel-chair and wal ker combi nati on; the saf e-wal ker i s equi pped wi th the f ol I owi ng safety and conveni ence features: (1) a suspension frame from which the user of the safe-walker is suspended in a support frame by means of a chest harness and if required by a pelvic harness; and (2) a moveable seat which shifts away from the sitting location of the wheel-chair when the user moves up to walk, and automatically moves back to the sitti ng position when the user col I apses or f al I s or moves down to rest.

[006] The device will be very useful in hospitals and clinics, physio-therapy labs, and in all facilities where people who are temporarily or permanently physically challenged in their walking abilities and balance while upright [007] In one embodiment the present invention provides a safe-walker. The safe-walker comprises: a wheel-chair frame with two seat support members, with each seat support member being made from a roller-track; a moveable seat made up of a plurality of seat slats, with each seat si at bei ng I i nked to an adj acent seat slat by a f I exi bl e connecti ng member and the ends of each seat slat being moveable along an inside of the associated roller-track; a support frame extendi ng up from a rear of the wheel -chai r frame; and a I i nkage connecti ng the moveable seat at a seat slat to an upper point located on the support frame; so that when a user, weari ng a chest harness with the chest harness bei ng connected to the upper poi nt on the support frame, gets up from a sit position, the linkage is pushed up, thereby pulling the pi ural ity of seat si ats al ong the associ ated rol I er-track i nto a storage posi ti on and gi vi ng space for the user to wal k, and when the user moves to si t down, the I i nkage i s pul I ed down, thereby pul I i ng the pi ural ity of seat si ats i nto the sit posi ti on to support the user. [008] Preferably, each end of the seat slat terminates with a roller, with the roller being disposed to roll inside the associated rol I er-track and being supported by a roller bearing or a plain bushing. Preferably, the roller-track is formed in a substantially L-shape, with a substantially horizontal portion to support the seat si ats in the sit position and a substantially vertical portion disposed at the rear of the wheel -chair frame.

[009] Preferably, a cable support/anchor point or a hook point is provided on the support frame at a location disposed above the upper ροίηζ to provide a fail-safe feature and to prevent fall injury or fall trauma. [0010] Preferably, a wheel-chair arm support frame is pivoted. It is possible that the support frame is also pivoted or extensible; the seat slats can also be pivoted. These features allow the safe-walker to be foldable into a compact size.

[001 1 ] In one embodiment of the L-shaped roller-track, the substantially vertical portion is upward and the seat movement is top-down. In another embodiment the substantially vertical portion is downward and the seat movement is bottonvup; further, a pulley and a cable or chain goes over the pulley, with the cable or chain connecting a top end of the I i nkage with a I owest seat slat when the seat si ats are i n the stored positi on. [0012] In another embodiment, the present i nvention provides a method for configuri ng a safe-walker. The method comprises: configuring a seat of a wheel-chair frame with a plurality of seat slats; flexibly linking each seat slat to an adjacent seat slat and allowing the ends of the seat slat to move along an inside of an associated rol ler-track that supports the seat; extendi ng a rear of the wheel-chair frame with an upward support frame; and connecting a linkage between the plurality of seat slats and a slidable locate point on the support frame; so that when a user, weari ng a chest harness with the chest harness connected to the slidable locate point, gets up from a sit position, the linkage is pushed up and the pi ural ity of seat slats are pul I ed away from the sit positi on, thereby gi vi ng space for the user to walk, and when the user moves to sit down, the linkage is pulled down and the plurality of seat slats are moved i nto the sit position to support/receive the user.

[0013] Preferably, the method further comprises extending the upward support frame to provi de an overhead cable support/anchor poi nt or hook poi nt, to serve as a fai l-safe feature to prevent f al I injury or f al I trauma.

[0014] Preferably, the method further comprises pivoti ng a wheel-chai r arm support frame to the wheel-chair frame to allow folding of the safe-walker. It is also possible to pivot the upward support frame, adj ustably extending the upward support frame, tel escopi cally or extendably, or pivoti ng the seat slats to achieve further foldi ng of the safe-wal ker.

B ri ef D escri pti on of the D rawi ngs

[0015] This invention will be described by way of non-l imiting embodiments of the present invention, with reference to the accompanying drawings, in which:

[0016] Figures 1A-1 B i llustrate two types of wheel -chairs for use with the present invention;

[0017] Figures 2A-2B illustrate a safe-walker according to an embodiment of the present invention;

[0018] F i gures 3A -3B ill ustrate a seat movement embodi ment for the safe-wal ker shown i n Figure 2A or 2B; [0019] Figures 4A-4B illustrate another seat movement embodiment for the safe-walker shown in Figure 2A or 2B;

[0020] Figures 5A-5B illustrate arrangements of the roller tracks employed in Figures 3A, 3B, 4A or 4B;

[0021 ] Figures 6 illustrates various views of the rollers shown in Figure 5A or 5B; [0022] Figure 7 illustrates folding of seat slats employed in the safe- walker;

[0023] Figure 8 illustrates folding of wheel-chair arms employed in the safe-walker; and

[0024] Figure 9 i 11 ustrates a fai l-safe feature accordi ng to another embodi ment of the present invention.

Detailed Description

[0025] One or more specific and alternative embodiments of the present invention will now be described with reference to the attached drawings. It shall be apparent to one skilled in the art, however, that thi s i nventi on may be i mpl emented without such specif i c detai I s. Some of the details may not be described at length so as not to obscure the invention. For ease of reference, common reference numerals or series of numerals wil l be used throughout the figures when ref erri ng to the same or si mi lar features common to the figures.

F igures 1A-1 B:

[0026] Figure 1A shows a wheel-chair WC of the big wheel type and which may be self- operated by the user himself /herself; Figure 1 B shows a wheel-chair WC of a small wheel type which normally requi res an attendant to push it around. However, the all small -wheels type will be used in the description that follows to reduce the possible distraction and covering up of other salient details by the big wheels in the drawings.

F igures 2A-2B:

[0027] Figures 2A-2B show the concept of the safe-walker. There is a support frame SF attached to the wheel-chair WC. The support frame SF provides an overhead cable support/anchor PS to support the user from falli ng down by means of a chest harness CH as well as to provide the user with a seat formed by a pl urality of seat slats WP, when the user is unable to or prefers to stand up or wal k. [0028] The user sits and moves around in the wheel -chair in the normal way. When he wishes to walk, he gets up and the wheel-chair seat slats WP move away (Figure 2A) on rollers running in roller tracks RT into an enclosure located at the back, either above the seat level or bel ow the seat I evel . In one embodi ment, the rol I er track RT has a cross- secti on of a I i pped C-channel, as shown in Figure 6.

[0029] When the user collapses or falls or moves to sit down to rest, the seat slats WP automatically returns from its stored position to the seating position (Figure 2B) so that the user is gently supported in the sitting position without fear of a fall injury or trauma.

[0030] It may be noticed that the cable from the overhead cabl e support/anchor PS is adjusted to be just right in length when the worker is sitti ng, and hence it hangs loose when he is standi ng up or wal ki ng.

[0031 ] The automatic seat movement SM mechanism (shown in Figures 3A-3B) is operated by another rigid link E P attached to the chest harness CH at the shoulder level E, moved to the : seat- stored^" position (BD or BC) while the user is standing or walki ng, and to the : seat- in- pi ace^" position (A B) as the user sinks or voluntarily sits down.

[0032] As long as the automatic seat movement SM mechanism works correctly, there will be no need for the overhead cable support/anchor P S system But the cable support/anchor PS system serves both as a back-up i n the rare event that the seat movement SM mechanism fails to operate, and also for the more likely sudden collapse or stumbling that may happen due to dizziness or loss of balance of the user.

[0033] A handle H H is provided for the user to stabilize himself and move the wheel -chair WC with him when he stands or walks. This handle H H is located on the wheel-chair arm support but is not shown in the rest of the figures to avoid clutter. There are two ways the seat slats WP can be stored when not in use and moved to the sit position: 1. Top-down system (A BD), when the seat slats WP are stored at the back of the wheel- chair (DB) above the seat level; and 2. Bottonvup system (A BC), when the seat slats WP are stored at the back of wheel-chair base (CB), below the seat level.

F igures 3A-3B: [0034] Figures 3A-3B show the seat movement SM mechanism for automatic movement of the seat slats WP in top down mode, in the wheel -chair WC. The movement is effected by a metal linkage E F, E being rigidly attached or flexibly connected to the chest harness CH, and F to the series of rollers carrying the seat slats WP.

[0035] T he rol I ers are pushed and/or pul I ed by means of straps attached to the metal I i nkage E F (just below label :SM ^"). The metal I i nkage E F has an adjustable projection bar E P to attach to the chest harness CH so that as and when the user moves substantial ly vertically standing up or sitting down, the projection bar E P moves with hi m, pulling or pushing the seat slats WP within the grooved roller tracks RT located at the two sides of the wheelchair WC. To avoid clatter, the roller tracks RT supporti ng the seat are shown but the backrest of the wheel-chair WC is omitted. [0036] When the user is standing or walking (Figure 3A), the seat slats WP are stored out of the way (SS) in BD, above the seat level at the back. When he collapses or wishes to rest (Figure 3B), as he sinks down the seat movement SM mechanism pushes the seat slats WP i nto the sitti ng positi on (S P) i n A B . In another embodi ment the I i nkage E F or the proj ecti on bar E P may be made of a hard material, such as plastic, glass fibre, and so on, instead of a metal.

F igures 4A-4B:

[0037] Figures 4A-4B show the bottom-up movement for seat storage (whereas Figures 3A- 3B show the top-down movement). Here, the seat slats WP are moved into the seat- stored position SS in a recess BC below the seat level while the user is standing or walking, or are moved back i nto the sit positi on S P al ong A B . [0038] This linkage E F involves gears or cables running on pulleys to effect the seat movement. A lthough pul leys (P1, P2) are shown i n the schematic diagram, the actual seat movement SM mechanism may differ in detail, and may be omitted or hidden safely (and aesthetically) inside casings, which are not shown in the figures.

[0039] While the top-down movement system is simpler to manufacture and operate, the bottom-up movement system may have advantages in actual use, particularly where it is desired to make the wheel -chair and fall support frame SF foldable for storage and transportation.

F igures 5A-5B:

[0040] The seat movement SM mechanism comprises of a grooved metal rol ler track RT bent into an approximate : L ^" shape (upright for top-down movement system and i nverted for bottom- up movement system) with a series of rollers with ball bearings or plain bushings.

[0041 ] A n angl e si ightly greater than 90 degrees is shown i n the figures, to conform to most wheel -chair shapes. But it may vary from 90 degrees to a somewhat greater angle as desired. There will be a canvas or other fabric for back rest, but is not shown in Figures 5A- 5B.

F igure 6:

[0042] This Figure 6 shows various views of the roller track (RT), rollers on ball bearings, and seat slats (WP) arrangements.

[0043] Actual device may differ in detail with the same functions.

[0044] The axles of the rollers carry seat slats WP made from wood, plastic, or other material for the user to sit on. Each seat slat WP is supported on the axle rod by triangular ribs, as shown in the elevation and cross-section views.

[0045] The series of rollers and seat slats WP are linked to an adjacent member by means of a flexible chain or a flexible connecting member, which is not shown in Figure 6.

F igure 7:

[0046] While the safe-walker described above will be the most rigid, economical and easy to maintain, modifications may easily be made to fold them into a width of about a third or less of their open width by making the seat slats WP fold at the middle i n a scissor- fashion when not i n use. [0047] Figure 7 shows one embodiment of such a folding embodiment. Each seat slat WP will be made of two parts (PQ, RS) mutually supporting each other via a common hinge T in the middle. [0048] Special means must be provided at the ends P, Q, R, and S to slot i nto the rollers/roller bearings at the grooved roller track RT to enable the seat movement SM between A B and BC or BD. F igure 8:

[0049] A n alternative, possi bly si mpl er and cheaper embodi ment (as shown i n F igure 8) wi 11 be to hinge the two wheel -chair arms and the two seat brackets AB a short distance (say 5 cm) away from thei r junctions with the vertical or nearly vertical wheel-chair back and base, with a hinge lock. When desired to be stored or transported, the hinge locks may be rel eased, and the two si des folded across the back.

[0050] The hinge locks (shown schematically as small circles) will have to be specially designed to revert to proper functioning of the seat movement SM upon opening up and locking.

[0051 ] Although not shown, the tall support frame SF may also be hinged at about mid- height and folded forward (or backward) to make the entire safe-walker quite compact. [0052] While what has been described refers to the basic principles involved, the actual seat movement SM mechanism may be considerably simplified by a short rigid arm attached to the chest harness at the back as at C in Figure 9, and to the top of the roller-chain withi n the rol I er track RT , i n such a way that when the user i s seated, the seat si ats W P wi 11 be moved to the horizontal support position, and when the user gets up to walk, the seat slats WP will automatically be pushed up to the vertical position.

[0053] Figure 9 shows one embodiment of such a simplified embodiment

F igure 9:

[0054] It is envisaged that the force necessary to move the roller-chain up or down will be smal l enough to be suppl ied by the user s effort in getting up or the body weight slumping down, and if it is found to be insufficient electronic and electrical devices may be used to faci I itate/actuate the seat movements.

[0055] In any case, there will be a fai I -safe mechanism consisting of a lanyard attached to the chest harness C H and to a hook (PH in Figure 9) at the top, such that if and when the seat si ats W P fai I to move down to support the downward movement of the user, the I anyard from the overhead hook PH will hold the user up and prevent hi m from crashing to the ground. Design:

[0056] The support frame SF and the seat slats WP will be designed to withstand the maximum load of a person anticipated to use the safe-walker with a high factor of safety, i ncl udi ng the smal I i mpact whi ch may happen when the user si umps on the seat.

[0057] A third pair of horizontal bars may be provided at the base between the front and back wheel axles to stiffen the support frame SF or wheel-chair WC further. In this case, to enable the method of folding in Figure 8 above, this pair of stiff ener bars will also be hinged in the same vertical line as the wheel -chair arm and seat level hinges.

[0058] The material of the wheel -chair frame may be aluminium or other light material. The moving parts are estimated to be within 5 or 6 kg. To avoid the user having to bear or move this weight with his chest harness C H, the weight of the moving parts may be counterbalanced by means of a counter-weight in a hidden casing or a spring of suitable stiffness but are not shown i n the figures.

[0059] In the worst case scenario of the seat movement SM mechanism failing to work, the user will simply be suspended in a collapsed state, by the chest harness C H from the overhead support/anchor PS or hook PH, yet still safe against fai I inj ury or trauma.

[0060] Unless something goes very wrong with the seat movement SM mechanism, the mechanism will only need a gentle nudge downward or upward at the top bar (near label SM) to continue to function i n moving the seat back and forth normally. [0061 ] In the wheel-chai r WC of the folding type which can be collapsed horizontally for storage and transportation, the vertical support frame SF may also be modified to fold vertically for better portability. Advantages: [0062] The Safe-Walker will combine the functions of a wheel -chair and walker, with the support frame SF incorporating the fall support from cable support/anchor PS or hook PH by a cabl e attached to the chest harness C H .

[0063] T he val ues added by the present i nventi on to these basi c f uncti ons are:

1. There is no need to change devices or locations while shifting back and forth from seated to standi ng/wal ki ng mode.

2. W hen user moves up to wal k, the wheel -chai r seat si ats W P move out of the way, and when he falls or moves down to rest the seat slats WP automatically move to receive/support hi m.

3. The cable to the overhead anchor PS or hook PH is a double precaution, providi ng a fail -safe safe-walker under all potential hazards.

4. The safe-walker may be used not only in hospitals, but also in offices and homes, with the same portability as current wheel-chairs. For treadmill use in physi o- therapy, the f rami ng may be modif i ed.

5. A s much as the physi ol ogi cal advantages, the psychol ogi cal benefits of i ncreased confidence and self-worth in the users ^" perception will be immeasurable.

Commercialization:

[0064] With increasing world-wide acceptance and encouragement of physically challenged persons both i n home and workpl ace envi ronments, manufacture and mass producti on of the Safe- Walker should pose no problems.

[0065] Inventor opines that by lowering costs, overheads and profits to the minimum, the ultimate cost differential between the Safe-Walker and the conventional wheel-chair will not be prohibitive, and the present invention will be a welcome and viable social and medical service. [0066] While specific embodiments have been described and illustrated, it is understood that many changes, modifications, variations and combinations thereof could be made to the present invention without departing from the scope of the present invention. For example, the support frame may be extensible, either telescopically or by attaching an additional secti on, so that the height of the safe-wal ker can be adj ustably extended or shortened.

Claims

C LAIM S:

1. A safe-wal ker comprisi ng:

^" a wheel-chai r frame with two seat support members, with each seat support member bei ng made from a rol I er-track;

5 ^" a moveabl e seat made up of a pi ural i ty of seat si ats, wi th eac h seat si at bei ng I i nked to an adjacent seat slat by a flexible connecting member and the ends of each seat slat being moveable along an i nside of the associated roller-track;

^" a support frame extending up from a rear of the wheel -chair frame; and " a linkage connecting the moveable seat at a seat slat to an upper point located on o the support frame;

so that when a user, wearing a chest harness with the chest harness being connected to the upper point on the support frame, gets up from a sit position, the linkage is pushed up, thereby pulling the plurality of seat slats along the associated roller-track into a storage position and giving space for the user to walk, and when the user moves to sit down, the5 li nkage is pulled down, thereby pulling the plurality of seat slats into the sit position to support the user.

2. The safe-walker according to claim 1, wherein each end of each of the seat slats terminates with a roller, with the roller being disposed to roll i nside the associated roller-0 track and being supported by a roller bearing or a plain bushing.

3. The safe-walker according to claim 1 or 2, wherein the roller-track is formed in a substantially L-shape, with a substantially horizontal portion to support the seat slats in the sit position and a substantially vertical portion disposed at the rear of the wheel-chair frame.5

4. T he safe-wal ker accordi ng to any one of the precedi ng clai ms, further comprisi ng a cabl e support/anchor poi nt or a hook poi nt I ocated on the support frame at a I ocati on disposed above the upper poi nt. 0

5. T he safe-wal ker accordi ng to any one of the precedi ng clai ms, wherei n a wheel-chai r arm support frame i s pivoted, whi ch al I ows the wheel-chai r frame to be f ol ded i nto a compact size.

6. The safe-walker according to claim 5, wherein the support frame is pivoted or extensible, which allows the safe-walker to be folded and/or shortened further in compactness.

7. T he saf e-wal ker accordi ng to any one of the precedi ng cl ai ms, wherei n each seat slat is pivoted so that at least the seat is foldable.

8. T he saf e-wal ker accordi ng to any one cl ai ms 5-7, further compri si ng a handl e I ocated on each of the wheel -chai r arm support frame.

9. The safe-walker according to claim 3, wherein the substantial ly vertical portion is upward and the seat movement top-down.

10. The saf e-wal ker according to claim 3, wherein the substantial ly vertical portion is downward and the seat movement i s bottom- up.

11. The safe-walker according to claim 10, further comprising a pulley and a cable or chai n goi ng over the pul I ey, with the cable or chai n connecti ng a top end of the I i nkage with a lowest seat slat when the seat slats are i n the stored position.

12. A method of conf iguri ng a saf e-wal ker compri si ng:

^" conf iguri ng a seat of a wheel-chai r frame with a pi urality of seat si ats;

^" flexibly linking each seat slat to an adjacent seat slat and allowing the ends of the seat si at to move along an inside of an associated roller-track that supports the seat;

" extendi ng a rear of the wheel-chair frame with an upward support frame; and

^" connecting a linkage between the plurality of seat slats and a slidable locate point on the support frame, so that when a user, wearing a chest harness with the chest harness connected to the slidable locate ροίηζ gets up from a sit position, the linkage is pushed up and the plurality of seat slats are pulled away from the sit position, thereby giving space for the user to walk, and when the user moves to sit down, the linkage is pulled down and the plurality of seat slats are moved into the sit position to support/receive the user.

13. The method according to claim 12, further comprises extendi ng the upward support frame to provide an overhead cable support/anchor point or hook point.

14. The method according to claim 12 or 13, further comprises pivoting a wheel-chair arm support frame to the wheel -chai r frame to al I ow f ol di ng of the saf e-wal ker to a compact size.

5

15. The method according to any one of claims 12-14, further comprises pivoting the upward support frame to al I ow f ol di ng of the saf e-wal ker to a compact si ze.

16. The method according to any one of claims 12-14, further comprises adj ustably o extendi ng the upward support frame, tel escopi cal ly or attachi ng another secti on.

17. The method according to any one of claims 12-16, further comprises pivoting the seat si ats to al I ow at I east f ol di ng of the seat to achi eve compactness.