CA1248989A - Wheeled mechanism - Google Patents

Abstract

ABSTRACT OF THE INVENTION

A wheeled mechanism which may be used as a trolley or a walking frame for the disabled comprises a frame carried on at least two ground wheels on a single axle so as to be turnable about the said axle;
the frame includes an operating handle, and pivot-ally mounted to the frame is a rigid leg frame or member pivoted at or adjacent one end thereof to the main frame so as to be turnable about a second axis substantially parallel to the said wheel axle;
the length of this leg frame or member is such that the end remote from the second pivot axis is en-gageable on the ground in a first relative orien-tation of the leg frame or member and the main frame, and can be raised from the ground upon rel-ative turning movement of the leg frame or member and the main frame about the second axis.

Description

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3 The present invention relates to a wheeled mechanism 4 which can be used as a trol]ey for conveying loads or which may be adapted as a support frame for assist-6 ance with walking for the disabled.

8 One known prior art trolley is the so-called sack-9 barrow, which comprises a rigid generally L-shape frame with a pair of wheels pivoted at the inter-11 section of two approxima-tely orthogonal arms of the 12 frame. The lower arm is generally horizontal and 13 very much shorter than the vertical arm and this latter 14 has a pair of handles at the upper end.
16 Sackbarrows have the disadvantage -tha-t loading and 17 unloading involves tippiny the load to a substantial 1~ degree in order to introduce the platform constituted 19 by the horizon-tal arm of the L-shape frame. Further, the weight of the load is to a large extent effecti-21 vely carried by the operator through -the handle, parti-22 cularly if -the frame is inclined at a substantial angle 23 to the vertical in opera-tion, and -there is a risk that 24 the load will tip and fall off if the load-bearing platform is placed on the ground, for example, to allow 26 the operator to rest~ Other known prior art trollies 27 include a trolley having four wheels, two o~ which are 23 steerable, and which provides a load bearing platform 29 on a frame spanning the wheels. Such a -trolley is complex, expensive and difficult -to manoeuvre whilst, 31 although a sack-barrow is of simple cons-truction 9 it 32 is dif~icul-t to opera-te and requires great strength I ~ 33 o~ the user. Fur-ther i-t is necessary to lift a load i 34 from the ground up on -to the load-bearing platform of ~ 2 -a four wheel trolley, which particularly in the case

2 of the elderly or infirm, or if a rather hea~y load

3 is involved, can be a very serious disadvantage.
OBJECTS OF I`HE INVENTION

7 The primary obj ec-t of the present invention is to 8 provide a wheeled mechanism which can be used as a 9 load bearing -trolley or barrow and which will not suffer from the disadvantages of the known sack-barrow 11 and at the same time will be simpler and more economi-12 cal to manufac-ture than known four-wheeled trolleys,.

14 Another object of the invention is -to provide a wheeled mechanism usable as a trolley, in which the load can 16 if required be kept upright, without tilting, at all 17 times.

19 A further obj ect of the invention is -to provide a trolley which has a load platform ~vhich can be raised 21 or lowered by manipulation of the operating handle.

23 S-till another obiect of the inven-tion is to provide a 24 trolley in which the operator can safely lower the load if fatigued, and may also rest his or her weight on 26 the handle without risk of ~he trolley rolling away.

28 Yet a further objec-t of the invention is to provide a 29 trolley sui table for the elderly or infirm, which can be manipulated easily without requiring great strength 31 even when handling quite heavy loads such as, for 32 example, a 50kg sack o~ coal or the like.

34 S till a further object of the invention is to provide a trolley which can be used with only ond hand, lea~ing : :
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, 1 the other hand free for a stick, and for manipulation 2 of doors, gates, etc.

4 A general object o the invention is to provide a trolley by which a user can move a load from place to place without the load having to be lifted or 7 carried by the user at any time.

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2 , 3 According to the present invention there is pro-vided a wheeled mechanism for transporting a load or for other purposes; said mechanism com-6 prising a main frame, at least two ground wheels 7 mounted on said ~rame so as to be turnable about 8 a common axis, an operating handle on said frame, 9 substantially rigid leg frame means, pivotal con-nection means pivotally connecting said rigid leg 11 frame means at or adjacent one end -thereof on said 12 main frame so as to be turnable about a second 13 pivot axis substantially parallel to said common 14 axis, the length of said leg frame means being slightly less -than the distance from said pivotal con-16 nection means to the ground contacting points of said 17 wheels such that the end of said rigid leg frame 18 means remote from said second pivot axis is engage-19 able on the ground in a first relative orientation of said leg frame means and said main frame and is 21 raised from the ground upon relative turning movement 22 of said leg frame means and said main frame about:said 23 second axis to a second relative orientation thereof.
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With the leg frame or member raised from the ground 26 the wheels of the mechanism can be rolled in a con-27 ventional manner to allow the mechanism to be moved 28 freely and easily from place to place. If the mech-29 anism is adapted as a load-bearing trolley, the leg frame or member may be provided with a support 31 platform or container and it is a particular 32 feature of the present invention that the leg frame , ~ 5 ~1 ~;

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1 or member is movable between a first and a second 2 position with respect to 1he main support frame and 3 in the second position the support surface oP the 4 platform or container is generally parallel with the ground so that any load requiring it can be 6 maint-ained in a strictly upright orientation. Known 7 trolleys of -the sack-barrow type have inevitably 8 -til-ted the load in order to make it possible for 9 -the load to be raised from the ground.
11 It i5 further envisaged that the operating handle 12 may be linked to the main support frame by a cranked 13 portion thereof so that the operating handle is po-14 sitioned spaced from a vertical plane including the axis thereof in a direction away from the sup-16 port platform or container so that the leverage which 17 can be applied by the handle is sufficiently great 13 to be able to control even subs-tan-tial loads on 19 the platform or container without re~1uiring the application of a very great force at the handle.

22 I-t is a fur-ther fea-ture of the present invention 23 that relative movement between the main support 24 frame and the leg frame or member is limited by abutment stop means to determine the said firs-t 26 relative position. In this first relative po-27 sition the ground engaging end o the leg frame or 28 member is in contact with the ground and movement of ; 29 the handle in the same direction as displacement be-tween the second position and ~he Pirst position is 31 prevented by such abutment stop means, forces e~ertedon , .
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1 -the handle being transferred to the ground through the 2 ground-engaging means. When the operator wishes, 3 therefore, it is possible simply to lower the container ~ or platform onto the ground and to allow the weight of the user's body to rest on the handle without risk that 6 the mechanism will roll on the wheels. For the elderly 7 or infirm, therefore, who may require frequent rest 8 periods, this is a considerable advantage since the 9 mechanism can be used as a support to lean on at intervals during a passage between one place and another 11 transporting a load.

13 This aspect of the invention also enables it to be used 14 as a replacement for conventional ambulant assistance support frames for the infirm. People having injured 1~ legs or spines, can particularly benefit from this 17 arrangement. In such an embodiment the ground-engaging 18 member, instead of being formed as a platform or 19 container, is formed as a foot having frictional properties in order to increase the frictional 21 resistance between the foot and the ground. Such 22 properties may be provided, for example, by suitably 23 covering the ground-engaging surface of the foot with 24 rubber or plastics material having an appropriate coefficient of friction.

27 Likewise, in such an embodiment, the operating handle 28 may be provided as a U-shape partially encircling the 29 body of the user. Then, by rocking the support handle towards the user the ground-engaging foot can be 31 released from the ground allowing the wheels to roll so 32 that the invalid can walk par-tly supported by the 33 rolling wheels: in such circumstances it i5 envisaged g 1 that the ground-engaging foot will still be slightly in 2 contact with the ground so that a degee of frictional 3 resistance which can be controlled by the operator 4 acting on the handle, can be maintained for control purposes. When required it is only necessary then to 6 push the handle slightly away from the body of the 7 operator in order to re-engage the ground-engaging foot 8 on the ground so that the whole weight of the operator 9 can be allowed to rest on the support frame which, conveniently, is located just below elbow height.
11 Alternatively, an additional ground-engaging foot may be 12 provided on the other side of the axis of the wheels of 13 the main frame. The wheels may then only roll when a 14 balance position between two terminal positions is achieved and tilting of the operating handle to either 16 side of this balance position, beyond a certain angle, 17 will result in one or other of the two ground-engaging 18 feet coming into contact with the ground and preventing 19 further rolling movement of the wheels whilst at the same time providing support on which an operator may 21 lean.

23 Embodiments of the present invention may also be made 24 for special purposes, for example, a trolley may be formed for carrying and supporting gas bottles such as 26 propane or oxygen and acetylene bottles such as are used 27 for welding. In such an embodiment the leg frame or 28 member is formed as a frame with a support platform for 29 the gas bottles and restraining means at the top and bottom to ensure that they are held to this frame. In 31 such an embodiment it may be convenient to form the 32 pivotal connection between the frame of the wheeled 33 mechanism and the leg member in such a way that the two . ' ;

1 can be separated at will. Such a releasable pivo~al 2 connection may be made, for example, by suitable hook 3 shape engagement members on the frame, which can be 4 released upon displacement of the leg frame from the first to the second position in which the leg member 6 engages the ground; in this position the wheels of the 7 frame may be spaced from the ground thereby leaving 8 available movement in a vertical direction.

The present invention also comprehends a wheeled 11 mechanism as defined above formed as a trolley with 12 means for receiving an enlarged platform removably 13 attachable to the leg frame or member. Such enlarged 14 platform may be suitable, for example, for retaining a dustbin or like dimensioned article, and has the 16 advantage that, with the platform flat on the ground it 17 can be moved under the dustbin by slidi.ng, and 18 subsequently raised without tilting the dustbin simply 19 by displacing the frame from the second to the first position. In the first position the platform is held by 21 the frame spaced a short distane from the ground and in 22 a horizontal plane. Of course, like a sack-barrow, the 23 platform can be tilted to move the centre of gra~ity of 24 the article supported thereby more closely towards the axis of the ground wheels. However, because the 26 operating handle is spaced from the vertical plane 27 including the axis of the ground wheels when the 28 mechanism is in the said first position, additional 29 leverage for manipulating such weight _ g _ \~

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1 is readily available without requiring the operator 2 to exert a large force.
4 ~or convenience, the load-bearing platform may be removable or may be pivotally connected to the leg 6 member or frame constitu-ting -the leg member to allow 7 it to be folded flat against the frame~

9 Likewise, for convenience in storage, -the operating handle may be formed such that it can be folded flat 11 or telescoped within a par~ of the frarne.

13 It is envisaged that embodiments of the present in-14 vention may also be made wi-th a seat fixed to or att-achable to the leg member or frame cons-ti-tuting the 16 leg member for use as a baby carriage for supporting 17 and transporting infants. Such an arrangement has 18 the advantage of being self-braking in the sense that 19 when the operating h-andle is released, the mechanism as a whole will turn about the ground-engaging wheels un-21 til the leg frame comes into contact with -the ground 22 whereupon the frictional engagement of this with the 23 ground will prevent any movement or further movement.

Other features and advantages of the invention will 26 become apparen-t from a consideration of the following 27 description, in which reference will be made to the 2~ accompanying drawings, and which is provided purely 29 by way of non-li.mitative example~

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BRIEF DESCRIPTION OF THE DRAWINGS
2 --_ 3 Figure 1 is a perspective view of an embodiment 4 of the invention constructed as a load-bearing trolley;
6 Figure 2 is a side view of the embodimen-t of 7 Figure 1 in a firs-t position;
8 Figure 3 is a side view of the embodiment of 9 the invention in a second position;
Figure ~ is a side view of the embodiment in a 11 third operating position;
12 Figure 5 is a perspective view of an alternative 13 embodiment;
14 Figure 6 is a rear view of a second alternative embodiment; and 16 Figure 7 is a side view of the embodiment of 17 Figure 6.

19 DESCRIPTION OF THE PREFERI~ED EMBODIMENTS
21 Referring now to the drawings, the -trolley illus~
22 trated is generally indicated with the reference num-23 eral 11 and comprises a generally U_shape main frame 24 12 having arms 13,14 joined at their free ends by an axle 15 carrying two wheels 16,17, one at each 26 end.

28 From the bight portion of the U-shape frame 12 extends 29 an upright column 18 within which telescopically slides a handle extension 19 having, at its free 31 upper end, a transverse operating handle 20.

33 The telescopic handle extension 19 has a plurali-ty ` _ 11 _ ~ ~

1 of holes 21 and the column 18 has a spring loaded 2 plunger 22 engaged selectively in one of the holes 3 21 to determine the effective length of the handle 4 extension 19 by selection of its projection distance from the column 18. The height of the -transverse 6 handle 20 above -the ground can thus be easily adjusted.
7 Alternative adjustmen-t systems are also possible, 8 however.

0 Extending transversely across the U-shape frame 12 11 is a cross beam 23 pivoted abou-t an axis X-X at each 12 end to a respective arm 13,14 and haviny two down-13 wardly divergent support legs 24,25 to -the lower end 14 of which is secured a platform generally indicated 26 in the form of a shallow tray having a fla-t bot-16 tom 27 and left and right sides 28,29 and an upright 17 back 30. The interconnection between -the legs 24,25 18 and the platform 26 is made by welding or bolting the 19 lower ends of the legs 24,25 to the side walls 28,29 respectively in such a way tha-t a rigid interconnection 21 at a predetermined fixed angle be-tween the plane of -the 22 platform bottom 27 and the plane defined by the two 23 legs 24,25 is obtained. As shown in the drawings, 24 the side walls 28,29 are each formed as a very small lip over most of the length of the side,with an en-26 larged rear panel for attachment to the associated 27 leg 24 or 25. This allows a large object to be 28 placed across the platform 26 resting on the upper 29 edges of the side walls 28,2g. In an alternative em-bodiment (not shown) the platform is pivotally 31 mounted to the legs 24~25 such as by pivot pins, in 32 such a way that it can be folded flat for s-torage.

34 ~inally, the two arms 13,~ of the U-shape main _ 12 -.

B~g89 1 frame 12 are spanned by a curved strap 31 which 2 serves as an abutment to :Limit the pivotal move-3 ment of the legs 2~,25 about the cross member 23.
4 Movement of these legs 24,25 in the opposite dir-ection is limited by abutment of the platform tray 6 or the legs themselves against the axle 15. The 7 effect of the limited art:iculation of the sub frame 8 constituted by the legs 2~,25 and the cross member 9 23 with respect to the U-shape main frame 12 will be described hereinbelow with reference to Figures 2,3 11 and 4.

13 In an alternative embodiment (not illustrated) the 14 legs 24,25 are replaced by a single leg extending from the cross members 23 to the platform 26.

17 Referring now to Figure 2, the trolley is shown in a 18 first position with the platform 26 flat on the 19 ground. In this position the main frame 12 has been turned about the cross member 23, in a clock-21 wise direction as viewed in Figure 2, to its max-22 imum extent; the arms 13, 1~ o~ the main frame 12 23 have turned about the pivot constituted by the cross 24 piece 23 until, with the wheels 16,17 still on the ground, the pan 26 now rests flat on the ground.
26 With further clockwise movement of the main frame 12 27 the strap 31 will be brought into contact with the 28 legs 24,25 of the sub-frame, therefore preventing 29 any further movement of the handle 20 and locking the mechanism with the upright column 18 and handle 31 extension 19 at their highest position almost par-32 allel with the legs 24,25 of t~e sub-frame~

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The position illustrated in Figure 3 is achieved 2 by pUl1ing the handle 20 downwardly and to the left 3 as viewed in Figure 3 without displacing the plat-4 form 26 from the ground. This has the efect of turn-ing the main frame 12 about the pivot 23 which is 6 held fixed due to the contact of the platform 26 with 7 the ground and the rigid interconnection of the legs 8 24 ,25 with the platform 26- This movement is continued 9 until the axle 15 is brought into contact with the rear wall 30. Because the distance from -the ground 11 contacting point of the periphery of the wheels to 12 the pivot axis X-X of the cross member 23 is slightly 13 greater than the distance from the pivot 23 to the 14 back of the platform 26 where it joins the legs 24, 25 the back of the platform 26 is raised slightly 16 rrOm the ground as the axle 15 is brought into con-17 tact with the rear wall 30. At this point the front 13 edge of the bottom wall 27, of the platform 26 is 19 still in contact with the ground.
21 Finally, by further turning the handle 20 in an anti-22 clockwise direc-tion as viewed in Figure 4 the whole 23 mechanism is rocked about the wheels 16,l7 with the 24 main frame 12 and sub-frame constituted by the cross member 23 and legs 24 ,25 being locked together by 26 engagement of the axle 15 with the back wall 30 of 27 the platform 26 until this latter is horizontal, or 28 more precisely, parallel with the ground and raised 29 above it by the height h as shown in Figure 4.
31 Because the column 18 is at a substantial angle with 32 the plane de~ined by the main frame 12, the handle 33 20 is horizontally displaced, in this third posi~ion, -- i4 ~ , ' 1, 3r~9 1 by a distance D from the vertical cen-tre line through 2 the wheels 16,17 which is greater -than the distance 3 d of the assumed centre of gravi-ty at the centre of 4 the platform 26 of any load carried thereby. This leverage D/d gives the operator a considerable 6 mechanical advantage in handling the trolley, even 7 with a substantial load on the platform 26.

9 The distance D is also shown in Figure 3 to illustrate the small dis-tance S moved by the handle 20 in con-11 verting from -the position illustrated in Figure 3 12 to -that illustrated in F`igure 4, that is for raising 13 the front edge of the platform 26 to the horizontal 14 position from the inclined position of Figure 3.
16 The position of the handle 20 when the mechanism 17 is in the position illustrated in Figure 4 is shown 18 in broken outline in Figure 2 identified with the 19 reference numeral 20'~ The movemen-t of the handle between the two posi-tions can be seen -to be small 21 and easily accomplished so -that an opera-tor can 22 lower the load onto the ground and even allow his 23 or her own weight to rest on the handle 20 if 24 desired~ Because the platform 26 rests flat on the ground in the position illustrated in Figure 2 it 26 can easily be loaded by sliding the load onto the 27 bottom wall 27 of the platform 26 or by pushing the 28 trolley to i.ntroduce the bottom wall 27 under the 29 load. Should it be necessary to maintain the load vertical, for example, if this were a bucket of water 31 or the like, this can readily be achieved by holding 32 the trolley in the position of Figure 4 as it is 33 moved along.

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g Alternatively, if desired/ the handle can be moved 2 further in an anti-clockwise direction in order to 3 tilt the platform 26 so that a part o~ the load, 4 for ex~mple if this were a sack or other heavier

5 load, can be borne by the main frame 12 and balanced

6 by the inclination of this with respect to the

7 vertical.

9 The platform 26 may be pivotally mounted to the sup-10 port arms 2~ ,25 in order to allow i t to be folded 11 or storage~ Suitable abut.ment means ~not shown) 12 would be provided -to locate the platform 26 in the 13 working posi tion illustrated in Fiyure 1, and -the p 14 pivotal connection would allow it to be turned until 15 the platform 26 is approximately parallel with the 16 legs 24, 25 so that the front to back dimension of 17 the trolley is reduced substantiallyD

19 It will be appreciated from Figures 2 and 4 how the 20 present invention may be adapted as an aid to walking 21 for invalids or the infirm. The platform 26 would be 22 replaced by a ground-engaging foot having a suitable 23 groun d -engaging area and of a ma-teri al having a 24 high coefficient of fric tion on the lower face, and 25 the handle 20 could be replaced wi th a generally 26 1~ shape frame having horizontal arms which would pass 27 to either side of the body of a person standing imm 28 ediately behind the handle 20 so that suppor-t in 2g three directions is available.
31 Then, by leaniny forward or slightly sideways, the 32 user is completely supported with the frame in the 33 position illustra-ted in Figure 2 and the ground-34 engaging foot on the end of the legs 24 ,25 firmly 1 ~ -.

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1 in contact with the ground and the wheels 16, 17 2 spaced from the ground. When it is desired to move 3 forward, the handle 20 is rocked backwardly until the 4 wheels 16, 17 roll forward to the position as illu-5 s~rated in Figure 3, the ground-engaging foot is raised 6 partially so that the ~rictional resistance is reduced 7 to an extent sufficient to allow it to be moved by

8 sliding over the surface. If the user is su~ficiently

9 strong to walk almost unaided, the frame can be moved by depressing the handle 20 until the mechanism is 11 in the position illustrated in Figure 4 where the 12 user can then walk rolling the frame before him until 13 such time as a further period of rest is needed when 14 simply by moving the handle upwards and forwardly the 15 locked ground-engaging position is achieved~ There 16 is a possibility that the trolley could roll only 17 from an elderly or infirm user whose reactions are not 18 very fastO To avoid this happening the embodiment 19 formed as a walking frame may be fur-ther modified by 20 the provision of secondary or subsidiary legs near 21 the lower ends of the legs 24, 25 which legs project 22 over the axle 15 and are attached to a second ground-23 engaging foot which contacts the ground on the other 24 side of the line of contact between the wheels 16, 17 25 and the ground from the ground-engaging foot a-ttached 26 to the legs 24, 25. Thus, in such an embodiment, 27 the wheels 16, 17 will roll only when the handle 20 28 is loca~ed in an intermediate position where the two 29 ground-engaging feet are spaced from the ground and 30 movement in either direction away from this central 31 position will cause the mechanism to become grounded 32 and rigid. ~Iovement can then only take place when .` , ~ .

1 the operator is balanced and in control and should 2 any unbalance or lack of control occur then the mecha-3 nism will automatically adopt a safety position where 4 it will support the weight of a user resting on the handle~

7 Referring now to Figure 5, the embodiment illus-trated 8 has features in common with the embodimen-ts of Figures 9 1 _ 4 and corresponding or identical parts will be identified with the same reference numerals raised by 11 100, This embcdiment differs from the embodiment 12 previously described in that the legs 124, 125 connect-13 ed to the cross member 123 are not joined at their 14 bottom end by a platform or tray, but by a lower cross member 140, on which are pivotally mounted two 16 T-section supports 141, 142 having cranked end sections 17 143, 144 respectively at the pivoted end. A stop bar 18 145 also spans the legs 124, 125 just above the cross 19 member 140 and limits the pivotal movement of the members 141, 142 by engagement of -the cranlced end 21 sections 143, 144. The two support members 141, 142 22 can be used to carry any odd shaped article, or may 23 themselves support a platform or one of a range of 24 different platforms of different sizes specifically adapted for mounting thereon. The particular value 26 of the two linear support members 141, 142, however, 27 is for enabling the trolley to be used to carry a 28 conventional pallett on which any range of goods may 29 be stacked. In use, the trolley 111, operates in the same way as described for the embodiment of F`igures 31 1 _ 4 w:ith the linear support members 141, 142 lower-32 ed on the ground and the handle 120 raised, these .

1 members can be introduced into the space beneath the 2 load-bearing platform of a pallett. Subsequently, by 3 depressing the handle 120 to cause the trolley to turn 4 about the axis 115, the sub-frame constituted by the legs 124, 125 and the cross member 123 is raised from 6 the ground, elevating the platform supports 141, 142 7 and enabling a pallett supported thereby to be trans-8 ported in a substantially horizontal orientation to 9 any convenient location.
11 It is envisaged that interchangeable special purpose 12 platforms or supports may also be provided ~or the 13 embodiments of Figures 1 - 4, for example, to adapt 14 this embodiment for carrying a dus-tbin which may be too large to fit on the platform 26 illus-trated in 16 Figure 1. Such an adaptor may simple interengage on 17 the legs 24, 25 and rest on the platform 26. Like-18 wise, it is envisaged that the platform 26 may be 19 pivotally connected to the legs 24, 25 instead of being fixedly connected as shown, so that the plat-21 form bottom 27 may be tipped to a position lying 22 generally parallel to the plane defined by the legs 23 24, 25.

Referring now to the embodiment illustrated in Figures 26 6 and 7, there is shown a trolley adapted to carry gas 27 bottles such as are used for oxy-acetylene welding 28 equipment. Again, those components which are similar 29 in function or identical to the components in the ernbodiments 1 - 4 have been identified with the sarne 31 reference numerals raised by 200. Thus, a main frame 32 212 is shown carried on ground-engaging wheels 216, 33 217 and pivotally connected to a sub-frame incorpora 34 ting legs 224, 225. In this embodiment, however, the t ' . .
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legs 224, 225 are j Oined at the top by a cross member 2 246 and an encircling strap 241, and at the bottom by 3 a shallow tray-like container 242 which together act 4 -to retain two gas bottles 243, 244 in position on the sub-frame. The main frame 212 has a handle 220 which 6 is formed as a loop handle spanning the legs 213, 214 7 which have upwarcl extensions 213a, 214a pivotally 8 connected to the legs 224, 225 by pivots 260, 261.
9 This pivotal interconnection between the main frame 212 and the sub-frame comprising the legs 224,225 11 is a releasable connection, however, so that the main 12 frame 212 can be released and removed leaving the gas 13 bottles 243, 244 standing on the tray 242 in an up-14 right orientation. This embodiment has particular advantages since it allows the rnain frame with its 16 wheels to be removed away from the working environ-17 ment where the welding is to take place so that it 18 does not constitute an encumbrance, and, indeed, this 19 may be used for transporting other articles in combina-tion with a suitably shaped sub-frame connectable 21 thereto. Further, owing to the great weight of the 22 gas bottles when fully charged, the -trolley of the 23 invention has particular advantages in providing 24 additional leverage for control and in not requiring the bottles to be tilted to a steep angle before a 26 balance position is reached.

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Claims (17)

WHAT IS CLAIMED IS:

1. A wheeled mechanism for transporting a load or for other purposes; said mechanism comprising, a main frame, at least two ground wheels mounted on said frame so as to be turntable about a common axis, an operating handle on said frame, substantially rigid leg frame means, pivotal connection means pivotally connecting said rigid leg frame means at or adjacent one end thereof on said main frame so as to be turnable about a second pivot axis substantially parallel to said common axis, the length of said leg frame means being slightly less than the distance from said pivotal connection means to the ground contacting points of said wheels such that the end of said rigid leg frame means remote from said second pivot axis is engage-able on the ground in a first relative orientation of said leg frame means and said main frame and is raised from the ground upon relative turning move-ment of said leg frame means and said main frame about said second axis to a second relative orienta-tion thereof.

2. The wheeled mechanism of Claim 1, wherein said leg frame means is formed as a second frame having ground-engaging support means at the end thereof remote from said second axis.

3. The wheeled mechanism of Claim 2, wherein said ground-engaging support means comprises a load-bearing platform rigidly secured to said second frame and projecting therefrom transversely of a plane joining its point of attachmednt to said second frame with said pivoted end thereof.

4. The wheeled mechanism of Claim 2, wherein said ground-engaging support means are turnable between a first position in which they lie generally parallel to the length of said second frame and a second po-sition in which they project transversely of a plane joining the point of attachment thereof to said second frame with said pivoted end thereof.

5. The wheeled mechanism of Claim 1, wherein the pivotal movement of said leg frame means in one dir-ection is limited by contact with said frame to define said second relative orientation of said leg frame means and said main frame, and in the other direction is limited by abutment means carried by the said main frame to define said first relative orientation of said leg frame means and said main frame.

6. The wheeled mechanism of Claim 5, wherein with said wheels of said main frame in contact with the ground and said mechanism in said first relative orientation of said leg frame means and said main frame, the height of said pivotal connection means from the ground increases at least initially as said mechanism is moved from said first relative orientation of said leg frame means and said main frame towards said second relative orientation thereof.

7. The wheeled mechanism of Claim 5, wherein said leg frame means is formed with a ground-engaging foot and said operating handle is formed as a support frame enabling the mechanism to be used as an aid to walking for the disabled.

8. The wheeled mechanism of Claim 1, wherein said leg frame means is provided with a removable pan or tray for carrying loads having a large base dimension.

9. The wheeled mechanism of Claim 1, wherein said leg frame means is formed as a frame incorporating a cradle for supporting one or a plurality of gas bottles.

10. The wheeled mechanism of Claim 1, wherein said pivotal connection between said leg frame means and said main frame is releasable in such a way as to allow said wheeled frame to be removed leaving said leg frame means standing on the ground.

11. In a wheeled mechanism for transporting a load;
said mechanism comprising, a main frame including two main frame members defining a main frame plane in which the parts of the said main frame lie, at least two ground wheels mounted on said main frame so as to be turnable about a common first pivot axis, lying in said main frame plane, an operating handle joined to said main frame at the upper end of said main frame, said operating handle extending at an angle with respect to said main frame plane on a first side of said main frame plane, substantially rigid secondary frame means having an uppermost end and a lowermost end, pivotal connection means pivotally connecting said rigid secondary frame means to said main frame so as to be turnable about a second pivot axis substantially parallel to said first pivot axis, and load platform means carried by said secondary frame means at said lowermost end thereof, the improvement wherein:
said rigid secondary frame means includes an upper transverse pivot meter at said uppermost end thereof, said pivotal connection means pivotally connecting said rigid secondary frame means to said main frame acting to interconnect said upper transverse pivot member at said uppermost end of said rigid secondary frame means to said main frame, first secondary frame limit stop means acting to limit the pivoting movement of said secondary frame means with respect to said main frame in a first direction of pivotal movement to determine a first relative orientation of said secondary frame means and said main frame, second secondary frame limit stop means acting to limit the pivoting movement of said secondary frame means with respect to said main frame in a second direction of pivotal movement opposite said first direction of pivotal movement to determine a second relative orientation of said rigid secondary frame means and said main frame, in which said second relative orientation said rigid secondary frame and said platform means thereof both lie on a second side of said main frame plane opposite said first side thereof, the length of said secondary frame means being less than the distance from said pivotal connection means to the ground contacting points of said wheels by only a small amount such that in said first relative orien-tation of said rigid secondary frame means and said main frame the end of said rigid secondary frame means remote from said second pivot axis is engageable on the ground with said load platform being substantially parallel to and in contact with the ground and said ground wheels being also in contact with the ground, whereby said mechanism is in a stable configuration allowing said platform to be loaded and unloaded, wherein said platform is raised from the ground upon relative turning movement of said rigid secondary frame means and said main frame about said second axis to said second relative orientation thereof whereby to permit transport of a load on said load platform with said load platform being substantially horizontal, and wherein upon such relative turning movement of said rigid secondary frame means and said main frame to pass from said first relative orientation to said second relative orientation said load platform experiences no substantial tipping from said substantially horizontal position that it occupies in both said first and said second relative orientations.

12. The wheeled mechanism of Claim 11, wherein said main frame includes an axle joining said at least two ground wheels, and said second secondary frame limit stop means is defined by said axle whereby contact between said rigid secondary frame and said axles determines the limit of relative pivoting movement between said rigid secondary frame and said main frame.

13. The wheeled mechanism of Claim 11, wherein with said wheels of said main frame in contact with the ground and said mechanism in said first relative orientation of said rigid secondary frame means and said main frame, the height of said pivotal connection means from the ground increases at least initially as said mechanism is moved from said first relative orientation of said rigid secondary frame means and said main frame towards said second relative orientation thereof.

14. The wheeled mechanism of Claim 11, wherein said rigid secondary frame means is formed as a frame incorporating a cradle for supporting at least one gas bottle.

15. The wheeled mechanism of Claim 11, wherein said pivotal connection between said rigid secondary frame means and said main frame is releasable in such a way as to allow said wheeled main frame to be removed leaving said rigid secondary frame means standing independently on the ground.

16. The wheeled mechanism of Claim 11, wherein said load platform means is formed as a tray rigidly secured to said rigid secondary frame means and projecting therefrom transversely of a plane joining its point of attachment to said rigid secondary frame means with said pivoted end thereof at said second pivot axis.

17. The wheeled mechanism of Claim 11, wherein said load platform means is turnable between a rest position in which it lies generally parallel to the length of said rigid secondary frame means and an operative position in which it projects transversely of a plane joining its point of attachment to said rigid secondary frame means with said second pivot axis.