CA1288033C - Invalid's wheelchair and like conveyances - Google Patents
Invalid's wheelchair and like conveyancesInfo
- Publication number
- CA1288033C CA1288033C CA000540101A CA540101A CA1288033C CA 1288033 C CA1288033 C CA 1288033C CA 000540101 A CA000540101 A CA 000540101A CA 540101 A CA540101 A CA 540101A CA 1288033 C CA1288033 C CA 1288033C
- Authority
- CA
- Canada
- Prior art keywords
- conveyance
- wheel
- conveyance according
- frame
- carrier
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 230000005484 gravity Effects 0.000 claims abstract description 5
- 230000007717 exclusion Effects 0.000 claims abstract description 3
- 230000033001 locomotion Effects 0.000 claims description 3
- 230000008878 coupling Effects 0.000 claims description 2
- 238000010168 coupling process Methods 0.000 claims description 2
- 238000005859 coupling reaction Methods 0.000 claims description 2
- 230000000452 restraining effect Effects 0.000 claims 1
- 230000001143 conditioned effect Effects 0.000 description 3
- 239000011449 brick Substances 0.000 description 2
- 230000010006 flight Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000003028 elevating effect Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
Landscapes
- Handcart (AREA)
Abstract
ABSTRACT
To enable an invalid's wheelchair to negotiate stairways, it has a chassis frame equipped with ordinary motor-driven road wheels for level running and a pair of crawler belts for stair ascent or descent. Either the wheels or the belts may be selected, either to the exclusion of the other, as the mode of travel. A chair or like load carrier is movably mounted on the frame, and linkage is provided so the centre of gravity of the load is adjusted to give the required stability for the selected travel mode.
To enable an invalid's wheelchair to negotiate stairways, it has a chassis frame equipped with ordinary motor-driven road wheels for level running and a pair of crawler belts for stair ascent or descent. Either the wheels or the belts may be selected, either to the exclusion of the other, as the mode of travel. A chair or like load carrier is movably mounted on the frame, and linkage is provided so the centre of gravity of the load is adjusted to give the required stability for the selected travel mode.
Description
8~303;~
;' ' .
This invention relates to invalid' 8 wheelchairs and like conveyances: and, in relation to such conveyances, i8 concerned to enable them not only to be motive on level floors, pavements and the like, but also able to negotiate ~teps, flights of stairs, or ramps, either in ascent or descent.
The invention is, first and fore~ost, directed to the provision of a wheelchair conveyance for disabled per~ons, but it is conceivably applicable to conveyances or vehicles for other purposes where ability for uphill, downhill and level progress i8 required, and particularly where the centre of gravity of a load to be carried is relatively high, having regard to the vehicle's wheelbase, as it i8 in the cafie of an invalid's wheelchair.
Thus, a conveyance according hereto, instead of being equipped with a load carrier in the form of a chair, could serve as the trolley base for a remotely or otherwise controlled computer-governed automative robot: or, the load carrier of the conveyance could be in the form of a ~ox-liXe , receptacle or deck for simple transport of commodities generally. By way of example of the latter use, the conveyance could be used for keeping an upstairs floor of a building under construction Bupplied with bricks where the nature of the building renders the use of cranes, hoists, common brick conveyors and the like inconvenient or inexpedient~
Although the invention has general applicability as indicated, its prime purpose i8 in relation to wheelchairs, al~o as previously stated, and therefore the invention will ~ ` . , ~28803;3 - `
~ .
be further described herein, by way of example, $n terms of a wheelchair.
In summary, the invention provides a conveyance comprising:
a chassis frame, an upright ~upport column pivoted by its lower end on said frame for fore-and-aft swing movement relative to sa;d frame, a load carrier mounted on the upper end of said column, road wheels, whereof at least some are motor-driven, borne on said frame and providing the conveyance with a first wheel-base, two carrier-plates respectively placed at the sides of said frame and each carrying a motor-driven crawler belt the two of which define a second wheel-base for said conveyance, mounting means whereby said carrier-plates are translationally movable in unison thereby to bring one of said wheel-bases into floor contact to the exclusion of the other of said wheel-bases, and linkage mechanism coupling said support column and said mounting means where~y the angular disposition of ~did column i~ varied ~o as to dispose the vertical axis through the centre of gravity of ~aid load carrier plus its load within that one of said wheel-bases which is in floor contact.
An example of the invention is illustrated in the drawings he,rewith, wherein:
Fig. 1 i~ a side elevation of a wheelchair with its parts conditioned for level floor transport. Certain parts are omitted. For example only the ~keletal structure of the ., ,.~ .
~;~8~3(~3 chair type load carrier i8 ~hown, and one of the crawler-carrying mounting-plates i8 omitted for clarity, F~g. 2 substantially repeats Fig. 1 except for ~howing the wheelchair parts conditioned for up- or down-stairs travel, - Fig.3 is a plan omitting the load-carrier, Fiq. 4 is a section, on an enlarged scale, taken on line 4-4 in Fig. 3, and ~ ig. 5 is a perspective showing of some of the parts already shown in the earlier figures.
Referring to the drawings, the chassis frame is composed of ~ide-rails 6, centre-rail 7 and transverse ~hafts 8 and 9. ~ach side-ra,il 6 consists of a support-plate portion 10 rigidly fixed to a rod portion 11. Centre-rail 7 extends only between shafts 8 and 9 mainly to act as a steadying influence on the frame to counter-act lateral flexibility of plate portions 10 owing to their thinness. The rails 6 and 7 are furnished with bearing sleeves 12 fixed o~ the rails by way of angle chairs ~3. Shafts 8 and 9 are rotatable within sleeves 12 and are restrained against endwise movement relative thereto by collar~ 14.
The upright support column consists of a yoXe 15 and stem 16 fixed to the yoke. The lower end of the support column i5 thus in two parts each of which is pivotally mounted on shaft 9 by way of bearing sleeves 17. The upper end of the ~upport column is furnished with any suitable means for mounting a load carrier thereon. In this instance the load carrier is a chair, as indicated at 18, which may be fixed or laterally swivel-mounted on the top of the column.
~ 288033 `
Support-plate~ 10 each carry an electric motor 19 having a Atub drive shaft 20 with a front road wheel 21 keyed on it. These motors could be powered (where travel di~tances are relatively short) by flexible cable from conventional power lines, or possibly by way of a trolley wire ~upply system. For preference the motors are powered by a battexy carried on the conveyance. Conventional controls are provided so that the motors may be operated concertedly in forward or reverse, or individually or oppositely for steering purposes.
The distal ends of rod portions 11 carry vertical-axis sleeves 22 for ca~ter-type rear road wheels 23.
Wheels 21 and 23 provide the conveyance with its previously mentioned first wheel-base, being that wheel-base which i~ effective during level floor travel of the conveyance, as indicated in Fig. 1.
Mounting-plates 24 are placed at the sides of the chassis frame and both of them are closely and respectively encompassed by flexible crawler belts 25, having internal gear-teeth 26 and external tread-cleats 27. Belts 25 run about conventional idler pulleys freely-rotatabl~ ~ounted on plates 24. Two of these idler pulleys are indicated at 28.
Belt~ 25 are separately or combinedly operable by drive pinions 29 each of which has its own motor 30 mounted on the associated mounting plate 24- Motors 30 are controllable in the ~a~e w~y as previousiy explained in connçction with motors 19.
The mounting-plates 24 are operatively connected to the - ~l288~33 .
, chassis frame by way of front and rear bell-cranks 31 and 32, respectively,Xeyed on shafts 8 and 9 so that bell-cranks 3i will necessarily act as a single entity and bell-cranks 32 will rotate when shaft 9 rotates. Each of the mounting-plates 24 has bearing blocks 33 fixed on its inner side and these receive~pins 34 on the bell-cranks arms 35.
The bell-crank arms 36, at each side of the chassis frame, are coupled together by connecting rods 37.
~ Shaft 9 has a ~ector gear 38 keyed on it, and this gear is meshed by a drive pinion 39 keyed on stub shaft 40 of a V~motor 41 mounted on plate 42 fixedly mounted on frame member 7. A transmission lever 43 is fulcrumed at 44 between frame ~embers 11. One arm of lever 43 is coupled to sector gear 38 by link 45, ~nd the other arm of lever 43 is coupled, by link 46, to a lug 47 fixed on column 15/16.
As already stated the wheelchair as shown in Fig. 1 is conditioned for travel on the level; that is, with crawler belts 25 elevated above floor level 48.
When a step (49 in Fig. 2), or a flight of stairs, is to be climbed, it is approached in the direction indicated by arrow 50 (Fig. 2). Just prior to arrival at the rise, motor 41 is energised so.that the sector gear 38 is turned from the position shown for it in Fig. 1 to that shown in Fig. ~O
Thus (acting through shaft 9 and bell-cranks 31 and 32) lowering crawler belts 25 to floor level and elevating wheels 21 and 23 clear of that level. In this way the bottom flights of belts 25 become effective as the second wheel-base previously mentioned herein. During the wheel-base 1~88033 , change-over, the column 15/16 is 6wung about it~ pivot mount on shaft 9 (through the agency of lever 43 and links 45 and 46) from its position shown in Fig. 1 to that ~hown in Fig. 2 80 that the orientation of the load-carrier (18) i8 better suited to the climb, and at the same time the vertical axis.
of the centre of gravity of the load-carrier plus its load remain well within the lateral ambit of`the ~econd wheel-base.
During the approach to the rise, the belts 25 are, of course, moving in the direction indicated by arrow 51 in Fig. 2 so that when stair contact i6 made the cleat~ 27 ensure performance of the climb.
When a descent is to be made the same procedure is followed except that the descent is approached in the direction indicated by arrow 52 in Fig. 2.
It will be appreciated that whereas the pinion ~39) which causes part-rotation of the sector gear (38) to effect a wheel-base change-over, is preferably motor-driven (by .
motor 41); the shaft (40) on which pinion 39 is mounted could carry a worm-wheel meshed by a worm pinion on a shaft manually rotatable by a hand-wheel or the like.
;' ' .
This invention relates to invalid' 8 wheelchairs and like conveyances: and, in relation to such conveyances, i8 concerned to enable them not only to be motive on level floors, pavements and the like, but also able to negotiate ~teps, flights of stairs, or ramps, either in ascent or descent.
The invention is, first and fore~ost, directed to the provision of a wheelchair conveyance for disabled per~ons, but it is conceivably applicable to conveyances or vehicles for other purposes where ability for uphill, downhill and level progress i8 required, and particularly where the centre of gravity of a load to be carried is relatively high, having regard to the vehicle's wheelbase, as it i8 in the cafie of an invalid's wheelchair.
Thus, a conveyance according hereto, instead of being equipped with a load carrier in the form of a chair, could serve as the trolley base for a remotely or otherwise controlled computer-governed automative robot: or, the load carrier of the conveyance could be in the form of a ~ox-liXe , receptacle or deck for simple transport of commodities generally. By way of example of the latter use, the conveyance could be used for keeping an upstairs floor of a building under construction Bupplied with bricks where the nature of the building renders the use of cranes, hoists, common brick conveyors and the like inconvenient or inexpedient~
Although the invention has general applicability as indicated, its prime purpose i8 in relation to wheelchairs, al~o as previously stated, and therefore the invention will ~ ` . , ~28803;3 - `
~ .
be further described herein, by way of example, $n terms of a wheelchair.
In summary, the invention provides a conveyance comprising:
a chassis frame, an upright ~upport column pivoted by its lower end on said frame for fore-and-aft swing movement relative to sa;d frame, a load carrier mounted on the upper end of said column, road wheels, whereof at least some are motor-driven, borne on said frame and providing the conveyance with a first wheel-base, two carrier-plates respectively placed at the sides of said frame and each carrying a motor-driven crawler belt the two of which define a second wheel-base for said conveyance, mounting means whereby said carrier-plates are translationally movable in unison thereby to bring one of said wheel-bases into floor contact to the exclusion of the other of said wheel-bases, and linkage mechanism coupling said support column and said mounting means where~y the angular disposition of ~did column i~ varied ~o as to dispose the vertical axis through the centre of gravity of ~aid load carrier plus its load within that one of said wheel-bases which is in floor contact.
An example of the invention is illustrated in the drawings he,rewith, wherein:
Fig. 1 i~ a side elevation of a wheelchair with its parts conditioned for level floor transport. Certain parts are omitted. For example only the ~keletal structure of the ., ,.~ .
~;~8~3(~3 chair type load carrier i8 ~hown, and one of the crawler-carrying mounting-plates i8 omitted for clarity, F~g. 2 substantially repeats Fig. 1 except for ~howing the wheelchair parts conditioned for up- or down-stairs travel, - Fig.3 is a plan omitting the load-carrier, Fiq. 4 is a section, on an enlarged scale, taken on line 4-4 in Fig. 3, and ~ ig. 5 is a perspective showing of some of the parts already shown in the earlier figures.
Referring to the drawings, the chassis frame is composed of ~ide-rails 6, centre-rail 7 and transverse ~hafts 8 and 9. ~ach side-ra,il 6 consists of a support-plate portion 10 rigidly fixed to a rod portion 11. Centre-rail 7 extends only between shafts 8 and 9 mainly to act as a steadying influence on the frame to counter-act lateral flexibility of plate portions 10 owing to their thinness. The rails 6 and 7 are furnished with bearing sleeves 12 fixed o~ the rails by way of angle chairs ~3. Shafts 8 and 9 are rotatable within sleeves 12 and are restrained against endwise movement relative thereto by collar~ 14.
The upright support column consists of a yoXe 15 and stem 16 fixed to the yoke. The lower end of the support column i5 thus in two parts each of which is pivotally mounted on shaft 9 by way of bearing sleeves 17. The upper end of the ~upport column is furnished with any suitable means for mounting a load carrier thereon. In this instance the load carrier is a chair, as indicated at 18, which may be fixed or laterally swivel-mounted on the top of the column.
~ 288033 `
Support-plate~ 10 each carry an electric motor 19 having a Atub drive shaft 20 with a front road wheel 21 keyed on it. These motors could be powered (where travel di~tances are relatively short) by flexible cable from conventional power lines, or possibly by way of a trolley wire ~upply system. For preference the motors are powered by a battexy carried on the conveyance. Conventional controls are provided so that the motors may be operated concertedly in forward or reverse, or individually or oppositely for steering purposes.
The distal ends of rod portions 11 carry vertical-axis sleeves 22 for ca~ter-type rear road wheels 23.
Wheels 21 and 23 provide the conveyance with its previously mentioned first wheel-base, being that wheel-base which i~ effective during level floor travel of the conveyance, as indicated in Fig. 1.
Mounting-plates 24 are placed at the sides of the chassis frame and both of them are closely and respectively encompassed by flexible crawler belts 25, having internal gear-teeth 26 and external tread-cleats 27. Belts 25 run about conventional idler pulleys freely-rotatabl~ ~ounted on plates 24. Two of these idler pulleys are indicated at 28.
Belt~ 25 are separately or combinedly operable by drive pinions 29 each of which has its own motor 30 mounted on the associated mounting plate 24- Motors 30 are controllable in the ~a~e w~y as previousiy explained in connçction with motors 19.
The mounting-plates 24 are operatively connected to the - ~l288~33 .
, chassis frame by way of front and rear bell-cranks 31 and 32, respectively,Xeyed on shafts 8 and 9 so that bell-cranks 3i will necessarily act as a single entity and bell-cranks 32 will rotate when shaft 9 rotates. Each of the mounting-plates 24 has bearing blocks 33 fixed on its inner side and these receive~pins 34 on the bell-cranks arms 35.
The bell-crank arms 36, at each side of the chassis frame, are coupled together by connecting rods 37.
~ Shaft 9 has a ~ector gear 38 keyed on it, and this gear is meshed by a drive pinion 39 keyed on stub shaft 40 of a V~motor 41 mounted on plate 42 fixedly mounted on frame member 7. A transmission lever 43 is fulcrumed at 44 between frame ~embers 11. One arm of lever 43 is coupled to sector gear 38 by link 45, ~nd the other arm of lever 43 is coupled, by link 46, to a lug 47 fixed on column 15/16.
As already stated the wheelchair as shown in Fig. 1 is conditioned for travel on the level; that is, with crawler belts 25 elevated above floor level 48.
When a step (49 in Fig. 2), or a flight of stairs, is to be climbed, it is approached in the direction indicated by arrow 50 (Fig. 2). Just prior to arrival at the rise, motor 41 is energised so.that the sector gear 38 is turned from the position shown for it in Fig. 1 to that shown in Fig. ~O
Thus (acting through shaft 9 and bell-cranks 31 and 32) lowering crawler belts 25 to floor level and elevating wheels 21 and 23 clear of that level. In this way the bottom flights of belts 25 become effective as the second wheel-base previously mentioned herein. During the wheel-base 1~88033 , change-over, the column 15/16 is 6wung about it~ pivot mount on shaft 9 (through the agency of lever 43 and links 45 and 46) from its position shown in Fig. 1 to that ~hown in Fig. 2 80 that the orientation of the load-carrier (18) i8 better suited to the climb, and at the same time the vertical axis.
of the centre of gravity of the load-carrier plus its load remain well within the lateral ambit of`the ~econd wheel-base.
During the approach to the rise, the belts 25 are, of course, moving in the direction indicated by arrow 51 in Fig. 2 so that when stair contact i6 made the cleat~ 27 ensure performance of the climb.
When a descent is to be made the same procedure is followed except that the descent is approached in the direction indicated by arrow 52 in Fig. 2.
It will be appreciated that whereas the pinion ~39) which causes part-rotation of the sector gear (38) to effect a wheel-base change-over, is preferably motor-driven (by .
motor 41); the shaft (40) on which pinion 39 is mounted could carry a worm-wheel meshed by a worm pinion on a shaft manually rotatable by a hand-wheel or the like.
Claims (10)
1. A conveyance comprising:
a chassis frame, an upright support column pivoted by its lower end on said frame for fore-and-aft swing movement relative to said frame, a load carrier mounted on the upper end of said column, road wheels, whereof at least some are motor-driven, borne on said frame and providing the conveyance with a first wheel-base, two carrier-plates respectively placed at the sides of said frame and each carrying a motor-driven crawler belt the two of which define a second wheel-base for said conveyance, mounting means whereby said carrier-plates are translationally movable in unison thereby to bring one of said wheel-bases into floor contact to the exclusion of the other of said wheel-bases, and linkage mechanism coupling said support column and said mounting means whereby the angular disposition of said column , is varied so as to dispose the vertical axis through the centre of gravity of said load carrier plus its load within that one of said wheel-bases which is in floor contact.
a chassis frame, an upright support column pivoted by its lower end on said frame for fore-and-aft swing movement relative to said frame, a load carrier mounted on the upper end of said column, road wheels, whereof at least some are motor-driven, borne on said frame and providing the conveyance with a first wheel-base, two carrier-plates respectively placed at the sides of said frame and each carrying a motor-driven crawler belt the two of which define a second wheel-base for said conveyance, mounting means whereby said carrier-plates are translationally movable in unison thereby to bring one of said wheel-bases into floor contact to the exclusion of the other of said wheel-bases, and linkage mechanism coupling said support column and said mounting means whereby the angular disposition of said column , is varied so as to dispose the vertical axis through the centre of gravity of said load carrier plus its load within that one of said wheel-bases which is in floor contact.
2. A conveyance according to claim 1 wherein said load carrier is a chair.
3. A conveyance according to claim 1 wherein said road wheels comprise a pair of front independantly motor-driven wheels and a pair of rear castor-wheels.
4. A conveyance according to claim 1 wherein said crawler belts are independantly motor-driven.
5. A conveyance according to claim 1 wherein said chassis frame comprises a pair of side-rails, front and rear shafts rotatable in bearings on said side-rails, and restraining means on said shafts whereby said side-rails are held each to the other in required spacing by said shafts.
6. A conveyance according to claim s wherein said support column is pivoted on said rear shaft.
7. A conveyance according to claim 5 wherein all of said road wheels are mounted on said side-rails.
8. A conveyance according to claim 5 wherein the means whereby said carrier plates are movable comprise, for each of said carrier plates, a pair of bell-cranes respectively keyed on said front and rear shafts and each having the free end of one of its arms pivot-connected to the related side-plate, a connecting-rod linking the free ends of the other arms of said bell-cranks, and means for part-rotating said rear shaft.
9. A conveyance according to claim 8 wherein the means for part-rotating said rear shaft comprise a sector gear keyed on said rear shaft, a drive pinion meshing said sector gear, and means to rotate said drive pinion.
10. A conveyance according to claim 9 wherein said linkage mechanism comprises a first order lever fulcrumed on said side-rails, and links whereby the free ends of the arms of said lever are respectively coupled to said sector gear and said support column.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000540101A CA1288033C (en) | 1987-06-19 | 1987-06-19 | Invalid's wheelchair and like conveyances |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000540101A CA1288033C (en) | 1987-06-19 | 1987-06-19 | Invalid's wheelchair and like conveyances |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1288033C true CA1288033C (en) | 1991-08-27 |
Family
ID=4135940
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000540101A Expired - Lifetime CA1288033C (en) | 1987-06-19 | 1987-06-19 | Invalid's wheelchair and like conveyances |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1288033C (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106394711A (en) * | 2016-11-10 | 2017-02-15 | 安徽工程大学 | Carrying device based on gravity center adjustment mechanism |
| CN111846069A (en) * | 2016-03-26 | 2020-10-30 | 刘金松 | AI balance car |
| CN113712747A (en) * | 2021-08-25 | 2021-11-30 | 江苏集萃复合材料装备研究所有限公司 | Dual-purpose intelligent wheelchair for flat ground and stairs and use method thereof |
| CN117734843A (en) * | 2024-02-20 | 2024-03-22 | 成都理工大学 | Obstacle surmounting robot with adjustable body size |
-
1987
- 1987-06-19 CA CA000540101A patent/CA1288033C/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111846069A (en) * | 2016-03-26 | 2020-10-30 | 刘金松 | AI balance car |
| CN106394711A (en) * | 2016-11-10 | 2017-02-15 | 安徽工程大学 | Carrying device based on gravity center adjustment mechanism |
| CN106394711B (en) * | 2016-11-10 | 2019-07-02 | 安徽工程大学 | A carrier device based on a center of gravity adjustment mechanism |
| CN113712747A (en) * | 2021-08-25 | 2021-11-30 | 江苏集萃复合材料装备研究所有限公司 | Dual-purpose intelligent wheelchair for flat ground and stairs and use method thereof |
| CN113712747B (en) * | 2021-08-25 | 2023-09-05 | 江苏集萃复合材料装备研究所有限公司 | Dual-purpose intelligent wheelchair for flat ground and stairs and application method thereof |
| CN117734843A (en) * | 2024-02-20 | 2024-03-22 | 成都理工大学 | Obstacle surmounting robot with adjustable body size |
| CN117734843B (en) * | 2024-02-20 | 2024-04-30 | 成都理工大学 | Obstacle surmounting robot with adjustable body size |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |