GB2113625A - Collapsible trolley - Google Patents

Abstract

A collapsible trolley has a base 12 and a back 14 hinged together with a linkage 38 extending between them. The linkage 38 includes two rods 46, 48 hinged to each other and to the base 12 and back 14 respectively. A central member 40 is connected to or adjacent the hinge of the two rods 46, 48 and extending via a link rod 44 to the hinge of the base 12 and back 14. A strut 52 extends between the central member 40 and the upper rod 46. When the trolley folds, the strut 52 hinges (or alternatively slides on the rod 46) permitting the central member 40 to pivot in a direction opposite to the direction of folding of the trolley. This pivots the link rod 44 and reduces the distance between the hinge of the two rods 46, 48 and the hinge of the base 12 and back 14. The bracing provided by the rods 46, 48 is removed and the trolley folds. Loads are carried over the strut 52 and this biasses the linkage 38 in the unfolded position. <IMAGE>

Description

SPECIFICATION Collapsible trolley The present invention relates to collapsible trolleys.

Trolleys for carrying luggage and/or shopping need to be strong enough to support heavy loads safely and securely but at the same time be light enough to be portable when they do not carry a load. This is usually achieved by making the trolley collapsible so that, when it is not in use, it may be folded up and carried, e.g. in the boot of a car. The problem with such trolleys is that it is difficult to provide a trolley frame which can be collapsed but which can bear heavy loads.

It has now been found that a suitably strong frame may be provided by a linkage in which, when the frame is folded, a central member pivots in the opposite direction to the direction of folding of the frame. This is the first aspect of the present invention.

Such a linkage may be biassed open by the weight of a load on the trolley or by the weight of parts of the linkage itself. Increasing the load decreases the risk of collapse of the frame.

The central member may be connected to the hinge of a link extending between the base and back portions of the frame, the base back portions of the frame being hingedly connected together. The central member is then connected by a linking part to the hinge of the base and back portions. This supports the link extending between the base and back portions in an extended position, thereby holding the frame in the open position.

Rotation of the central member removes the support for the link between the base and back portions, which hinges, so that the frame folds up.

An additional link may be provided, extending from the central member to a point on the frame or linkage, which link is generally parallel to the base portion of the frame. This biasses the linkage open and helps to prevent accidental pivoting of the central member. It may also be used to support the load. This additional link may be pivotally secured to the central member and to the frame or linkage and hinged at an intermediate point along its length. Folding of this additional link about its hinge permits the frame to be folded.Alternatively, the additional link may be pivotally secured to the central member and slideably mounted on the frame or linkage. it may be secured at its position for which the frame is unfolded by a suitable fastening, release of the fastening permitting the additional link to slide on the frame or linkage, thereby permitting the frame to fold.

This type of frame has been found to be able to carry heavy loads yet can be made of a light material such as aluminium tubing. If the linkage is arranged vertically downward pressure on the link, e.g. due to gravity or to a load, biasses the linkage in the open position. The linkage may be arranged in a vertical plane and loads e.g. bags may be carried on either side of it. This is advantageous over known designs, in which the frame unfoids to form a "cage" for the load. With this known design it is difficult to get loads into and out of the cage and the volume of the cage limits the size of load that may be carried.

The wheels of the trolley may be secured to appropriate parts of the frame or may be secured to it via a rotatable joint. The wheels may be made to fold relative to the frame. To achieve this the wheel mounts are pivotally secured to the base of the trolley and to a strut or struts connecting them to a part of the linkage so that folding of the frame causes pivotting of the wheel mounts on the base of the trolley.

In another (second) aspect of the present invention, there is provided a trolley frame comprising an X-shaped member, the crosspieces of which are hinged about their junction, and a V-shaped member, the V-shaped member being hinged at its apex and having each of its two ends attached to a corresponding end of the X-shaped member.

With such an arrangement, when the free ends of the X are brought together the Xshaped member is closed and so is the Vshaped member.

This closing of the X-shaped member may be achieved by an arrangement in which the free ends of the X-shaped member are interconnected by a linkage extending between those ends. The linkage may comprise three rigid members pivotally connected in series to each other. Rotation inwards of the two outer rigid members reduces the gap between the free ends of the X-shaped member, thereby closing the frame. Preferably handles are provided on the two outer rigid members to facilitate rotation thereof.

If the V-shaped member described above is used as the base of a trolley, wheels may be mounted at its apex and at its ends, this three wheel arrangement is itself an independent aspect of the present invention. If the wheel at the apex of the V-shaped member is pivotable about a substantially vertical axis, the trolley may be steered easily. This is in marked contrast to four-wheel arrangements with all four wheels vertically pivotable. This latter type of wheel arrangement is difficult to steer accurately as the four wheels may align themselves in different directions.

If the features of the first and second aspects of the present invention are combined in one trolley, the folding of the X-shaped member may provide collapsing of the frame in one dimension (e.g. width) whilst the folding due to rotation of the central member provides collapsing in a second dimension (e.g.

height). These operations may be carried out independently and in either order.

The frame of a trolley according to the present invention may be made of, e.g. aluminium with a tubular or square cross-section. if this is done, the hinging of various parts of the linkage may be achieved by having one part extending over the other for part of its length with the hinge inward of the end. Then the lower part will abut against the extension preventing hinging in one direction, whilst pivoting in the opposite direction is unhampered.

Embodiments of the present invention will now be described in detail, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side view of a trolley according to a first embodiment of the present invention; Figure 2 is a plan view of the trolley shown in Fig. 1; Figure 3 is a rear view of the trolley shown in Fig. 1; Figure 4 is a rear view similar to Fig. 3, but showing the trolley folded; Figure 5 is a view similar to Fig. 1, but showing the directions of folding of the trolley; Figure 6 shows the trolley of Fig. 5 when partially folded; Figure 7 shows the trolley of Fig. 5 when fully folded; Figure 8 shows a perspective view of a trolley according to a second embodiment of the present invention; and Figure 9 shows a perspective view of the trolley of Fig. 8 when folded.

Reffering first to Figs. 1 to 3, a collapsible trolley being a first embodiment of the present invention has a frame 10 having a generally V-shaped base portion 1 2 (Fig. 2) and a generally X-shaped back portion 14 (Fig. 3).

The base portion 1 2 is hinged at the apex 1 6 of the "V" and the back portion 1 4 has a pivot 1 8 at the centre of "X".

Ends 20, 22 of the base portion 1 2 are hingedly secured to the back portion 1 4 adjacent respective ends 24, 26 thereof. A bracing strut 28 extends between the ends 24, 26 of the back portion 1 4 to hold the latter open.

The bracing strut 28 has two parts 30, 32 hingedly connected to each other at the centre 34 of the bracing strut 28. One part 30 has a channel-shaped end which overlies the other part 32 along a portion of its length. Thus downward pressure of one part 30 on the other part 32 due to gravity biasses the bracing strut 28 in the fully extended position shown in Fig. 3.

When the centre 34 of the strut is raised, in the direction of arrow 36, the two ends 24, 26 of the back portion 1 4 are brought together, which also brings together the ends 20, 22 of the base portion 1 2. This collapsing of the frame 10 will be described in more detail later.

Extending between the base portion 1 2 and the back portion 14 is a linkage 38 which, when in the position shown in Fig. 1, holds the base and back portions 1 2 and 14 respectively so that they are inclined at an angle of a little over 90 relative to each other. The linkage 38 comprises a first central member or cross-piece 40, one end 42 of which is hingedly connected to one end of a link rod 44, the other end of the link rod 44 being hingedly connected to the centre of the strut 28. The end 42 of the first cross-piece 40 is in the form of a channel extending under the link rod 44 when the linkage 38 is in the position shown in Fig. 1. Thus the link rod 44 braces the cross-piece 40 against rotation in a clockwise direction in Fig. 1.This bracing is similar to the biassing of strut 28 into a fully extended position.

The centre of the cross-piece 40 is pivotally connected to two rods 46 and 48 extending in opposite directions to each other and being substantially perpendicular to the cross-piece 40 when the linkage is in the position shown in Fig. 1. One rod 46 extends between the cross-piece 40 and the centre 1 8 of the back portion 14, to which it is hingedly connected.

The other rod 48 extends between the crosspiece 40 and the apex 1 6 of the base portion 12, to which it is hingedly connected. In this way, the two rods 46, 48 form the longest side of a triangle, the other two sides of which are formed by the base and back portions 12, 14, respectively, with the link rod 44 and part of the cross-piece 40 extending from the apex of the triangle to intersect the longest side.

The end 50 of the cross-piece 40 furthest from the link rod 44 is pivotally connected to one end of a strut 52, the other end of which is pivotally connected to a point intermediate along rod 46. The strut 52 extends generally parallel to the base portion 1 2 and is divided into two parts 54 and 56 hingedly connected together at the centre of the strut 52. One part 54 has a channel shaped end 58 which overlies the other part 56 of the strut 52.

Thus the strut 52 is similar in configuration to strut 28 and is biased into the fully extended position by gravity. Therefore, even when the trolley is carrying no load, it is biassed into the open position shown in Figs. 1 to 3.

The rod 48 extends beyond its connection with the base portion 1 2 and terminates in a rotatable joint 60 carrying a wheel or pair of wheels 62. The joint 60 permits the wheel to pivot about a generally vertical axis. Similarly each end 24, 26 of the back portion 14 also terminates in a wheel or pair of wheels 64, 66, but these wheels 64, 66 can not pivot about a vertical axis. The trolley is thus mounted on three wheels, the front one of which (wheel 62) is pivotable so that the trolley can be steered by a person pushing it from behind the back portion 14. This threewheel arrangement permits maximum manoeuverability, without the difficulty experienced, when all wheels are pivotable about a vertical axis, that the trolley does not always move in the direction it is pushed.

The configuration of the handles 68 of the trolley is shown in Fig. 3. Each handle 68 is rigidly connected to a plate 70 which has two spaced pivots 72 and 74. One pivot 72 is pivotally connected to the upper ends 76 of the back portion 14 whilst the other pivot 74 is pivotally connected to a rigid bar 78 interlinking the plates 70. This mechanism assists in folding the trolley as will be described later.

As shown by dotted lines in Figs. 1 and 2, the trolley can carry a number of bags 80 which are suspended from hooks 82 on the linkage 38. Alternatively, bags may be hung over the strut 52, which for this purpose may be elongated beyond its connection with cross-piece 40 and rod 46, as shown by dotted lines 84 in Fig. 1. Downward pressure on the strut 52, or on the hooks 82 acts on the linkage 38 to hold it in the open position shown in Figs. 1 to 3. It has been found that this configuration of linkage 38 permits very high loads to be carried by the trolley.

The frame 10 is also provided with straps 86, 88 extending across the base portions 1 2 and the back portion 1 4 which may act as supports for bags on the trolley.

The folding of the trolley will now be described. It comprises two separate movements which may be performed independently and in either order. These movements are: a) the folding shut of the base portion 1 2 and the back portion 14 about apex 1 6 and centre 1 8 respectively; and b) the folding together of the base portion 1 2 and the back portion 14 about their hinged connection at the ends 20, 22 of the base portion 1 2.

The folding shut of the base and back portions, 1 2 and 14 respectively will be described first with reference to Figs. 3 and 4.

From the position shown in Fig. 3, the centre 34 of the strut 28 is raised in the direction of arrow 36, e.g. with the foot. This breaks the rigidity of the link that the strut 28 provides and, if it were not done, the strut 28 would resist inward movement of the ends 24, 26 of the back portion 1 4. Once the centre 34 of the strut 28 has been moved upwards a short distance, the trolley can then be folded shut by use of the handles 68 alone.

If the handles 68 are pushed downwardly and inwardly in the direction of arrows 90 in Fig. 4, the plates 70 are caused to pivot in the same direction as the handles 68 about their pivots 74 on the bar 78. This moves the pivots 72, and hence the top ends 76 of the back portion 14, together, closing the X shape of the back portion 14 as shown in Fig.

4. As the bottom ends 24, 26 are brought together by the hinging of the back portion about the centre 18, the ends 20, 22 of the base portions 1 2 are brought together, the base portion 12 hinging about its apex 16.

Thus, except for the initial lifting of strut 28, the entire operation of folding shut the base and back portions 1 2 and 14 respectively, is controlled by movement of the handles 68.

To open out the base and back portions 1 2 and 14 respectively, the handles 68 are moved outwardly and upwardly in the opposite direction to arrows 90 thereby opening out the "X" of the back portion 14. This movement of the handles 68 is continued until the strut 28 is fully extended. This process can be assisted by downward pressure on the centre 34 of the strut 28 in the opposite direction to arrow 36, e.g. by the operator placing a foot on the strut 28.

The folding together of base and back portions 1 2 and 14 respectively will now be described with reference to Figs. 5 to 7.

With the frame 10 in the open position as shown in Fig. 5, the centre of the strut 52 is lifted upwardly, causing the two parts 54 and 56 of the strut to pivot about their ends in the direction of arrows 92, 94 respectively. Once the rigid link, formed by strut 52 when in the fully extended position, is broken in this way, the top part of the back portion 14 can be moved forward relative to the base portion 1 2 by pushing on the handles 68. As the back portion 14 moves forward in the direction of arrow 96, the parts 54 and 56 of the strut 52 continue to move in the direction of arrows 92, 94 but also the cross-piece 40 pivots anticlockwise in Fig. 5, in the direction of arrow 98. This pivoting of the cross-piece 40 causes hinging of the link rod 44 about its connection with the strut 28, in the direction of arrow 100.

When the cross-piece 40 and the link-rod 44 pivot in the direction of arrows 98, 100 respectively, the distance between the strut 28 and the end of the rod 48 connected to the cross-piece is reduced, causing the rod 48 to pivot about its connection with the base portion 1 2 in the direction of arrow 1 02.

The pivoting of the cross-piece 40 continues until it lies nearly parallel to rod 46, with the strut 52 fully folded. The position of the linkage 38 is then as shown in Fig. 6.

Movement of the handles 68, and hence the top of the back portion 14, forward in Fig.

6 continues the folding process. The crosspiece 40, the rod 46 and the strut 52 all move in the direction of arrow 104, pivoting about the connection of the cross-piece 40 with rod 48. The rod 48 continues to move downwardly in the direction of arrow 106.

This folding is continued until the trolley is fully folded as shown in Fig. 7, with the whole of the back portion 1 4 coming down on top of the base portion 12.

To unfold the trolley, the process is re versed. The handles 68 are raised from the position shown in Fig. 7 and the back portion 14 pivots in the opposite direction to arrow 108. The linkage unfolds until the position shown in Fig. 5 is reached, in which the strut 52 is fully extended and cross-piece 40 is braced against link rod 44.

A second embodiment of the present invention will now be described with reference to Figs. 8 and 9.

The collapsible trolley of the second embodiment of the present invention has a frame having a generally V-shaped base portion formed by two struts 200, 202 the end of each of which is secured to an apex piece 204. The trolley also has a generally V-shaped back portion formed by two struts 206, 208, ends of which are pivotally connected to an apex piece 210. The ends of the struts 200, 202 furthest from the apex piece 204 are pivotally secured to brackets 212, 214 respectively which are mounted on the struts 206, 208 adjacent the ends of those struts furthest from the apex portion 210.

A bracing strut formed by two side parts 216, 218 and a central part 220 is connected between brackets 212, 214. One end of each of the side portions 216, 218 is pivotally secured to a corresponding bracket 212, 214 on a respective one of the struts 206, 208 of the back of the frame, at right angles to the connection of the struts 200, 202. The other ends of the side portions 216, 218 are hingedly connected to opposite ends of the central portion 220. The central portion 220 of the bracing strut has a channel-shaped cross section so that parts of the central portion 220 overlie the respective side portions 216, 218.Thus downward pressure due to gravity of the central portion 220 on the side portions 216, 218 biasses the bracing strut in the fully extended position shown in Fig. 8, thereby holding the back portion of the frame and hence the base portion also in the open position shown in Fig. 8. This is generally similar to the action of the bracing strut 26 in the first embodiment.

A linkage extends between the base portion and back portion respectively so that they are inclined at an angle of a little over 90 relative to each other. The linkage has a rod 222, one end of which is pivotally connected to the apex portion 204 of the base portion and is hingedly connected at a point adjacent (but not at) its opposite end to an end of a second rod 224 which extends to the apex piece 210 of the back portion of the frame.

The free end of the rod 222 is hingedly connected to an intermediate point on a central member or cross-piece 226. One end of the cross-piece 226 is hingedly connected to a link rod 228 which extends to the central portion 220 of the brace between the struts 206, 208 of the back portion of the trolley.

Thus, the two rods 222, 224 form the lon- gest side of a triangle, the other two sides of which are formed by the base portion and the back portion, with the link rod 228 and part of the cross-piece 226 extending from the apex of the triangle to intersect the longest side. This is very similar to the configuration of linkage achieved by the rods 46, 48 the base and back portions 1 2 and 14 and the link rod 44 and cross-piece 40 of the embodiment of Fig. 1.

The cross-piece 226 extends beyond the rods 222, 224 and the end furthest from the link rod 226 is pivotally connected to one end of a strut 230. The other end of the strut 230 is pivotally connected to a slider 232 mounted on the upper rod 224. When the trolley is in the unfolded position shown in Fig. 8, the slider 232 is held in the position shown between a stop (not shown) which prevents sliding of the slider 232 down the rod 224 towards the cross-piece 226 and a fastening 234 which prevents sliding towards the apex piece 210. This fixing of the slider 232 relative to the rod 224 fixes the position of the cross-piece 226 and hence the linkage is maintained in in its unfolded position.

When the fastening 234 is released and the cross-piece 220 of the bracing strut between the struts 206, 208 of the back portion is raised, the centre piece 226 of the linkage pivots in a clockwise direction (as seen in Fig.

8). This causes the link rod 228 to pivot in a counter clockwise direction producing the distance between the end of the strut 222 and the brace between the struts 206, 208 of the back portion. The two rods 222, 224 hinge about their interconnection and the trolley folds simultaneously in two perpendicular directions as the apex piece 210 of the back portion folds towards the apex piece 204 of the base portion and the folding of the bracing strut 216, 218, 220 brings the struts 206, 208 of the back portion (and hence the struts 200, 202 of the base portion) together.

The rear wheels 236 of the trolley are rotatably mounted on the ends of the struts 206, 208 of the back portion. Each front wheel 238, however, is rotatably mounted in a support 240 which, in turn, is pivotally mounted on a bracket 242. Rotation of the support 240 relative to the bracket 242 permits steering of the trolley. The bracket 242 has an elongate portion 244, one end of which is hingedly mounted on a respective rod 200, 202 of the base portion and the other end of which is connected to a bar 246.

As can be seen, the bar 246 extends between the brackets for the front wheels 238. The bar 246 is connected via a link 248 to the rod 222. When the rod 222 rotates in a clockwise direction in Fig. 8 (as it does when the trolley is folded) the bar 1 46 is forced downwards, causing the elongate portion 244 of the bracket 242 to pivot about its mounting on the respective rod 200, 202 and this causes the bracket 242 (and hence the wheels) to be rotated relative to the base through approximately 90 . Thus, as shown in Fig. 9, the wheels can be folded so that their plane is parallel to the plane of the folded trolley thereby reducing the amount of space occupied by the trolley.

The handles 250 of the trolley are pivotally connected to the apex piece 210 of the back portion of the trolley so that they may be folded towards the struts 206, 208 respectively when not in use. As shown in Fig. 8, the handles 250 may have a channel 252 formed in their lower surface which receives respective struts 206, 208 when the trolley is folded, again reducing the space the folded trolley occupies A locking system is provided in the apex piece 210 to secure the handles 250 in their unfolded position. The locking system is activated by a slider 254 set in a slot 256 of the apex piece. From the folded position shown in Fig. 9, the handles 250 are raised to their unfolded position and the slider 254 is depressed to the limit of its travel in the slot 256, where it is held. This movement of the slider 254 triggers the locking system to lock the handles.To fold the handles, the slider 254 is released from its position in the slot 256 by depression of lever 258 and this releases the locking of the handles 250. Alternatively, the handles 250 and the slider 254 may be so interlinked that raising of the handles 250 from their folded to their unfolded position causes the slider 254 to move in the slot 256 to its depressed position and, after release of the slider 254 by lever 258 lowering of the handles 250 causes the slider 254 to return to its raised position shown in Fig. 9.

The slider 254 may also form part of a locking mechanism for the rod 224 so that, when the slider 254 is in its depressed position shown in Fig. 8, the rod 224 is fixed in the apex piece 210 so that it cannot pivot.

This prevents accidental folding of the trolley as the trolley can be folded flat only after the handles 250 have been folded.

When in use, loads are carried on the trolley over the strut 230. The weight of the load biasses the linkage in its open position.

Thus, the risk of accidental unfolding of the trolley is very small because the load prevents the slider 232 from sliding on the rod 224 towards the apex piece 210 even if the fastening 234 is accidentally released. The slider 254 in the apex piece 210 may also help to prevent accidental folding.

A trolley according to the present invention can be used for a large number of purposes, e.g. a shopping or golfing trolley or to carry luggage at railway stations. It has the advantage of being able to carry heavy and bulky loads yet fold to a small and portable size.

For lightness, the frame may be made of anodised aluminium with a tubular or boxed cross-section. Alternatively, steel may be used where strength is the over-riding consideration. Fibreglass may also be used.

Parts of the frame may be made of injection moulded plastics material. For example, the upper part (above line 110 in Fig. 1) of the back portion 14 may be formed in this way.

Claims (11)

1. A folding trolley having a frame including a base portion, a back portion connected to the base portion at a hinge, and a linkage adapted to brace the frame in an unfolded position and to fold to permit folding of the trolley, wherein the linkage has a hinged connection extending between points of the base and back portions spaced from the hinge, a central member pivotally attached to the hinged connection, and a link part connected between the central member and the hinge, wherein the central member is adapted to pivot only in the opposite direction to the direction of folding of the frame during folding of the frame.

2. A trolley according to Claim 1, wherein the central part extends beyond its attachment to the hinged connection in a direction away from the link part and a strut extends between that extension and the hinged connection in a direction generally parallel to the base when the frame is unfolded.

3. A trolley according to Claim 2, wherein the strut is hinged at an intermediate point along its length, the strut being adapted to fold about the hinge when the frame is folded.

4. A trolley according to Claim 2, wherein the strut is slidably connected to the hinged connection, the strut being adapted to slide on the hinged connection when the frame is folded.

5. A folding trolley according to any one of the preceding Claims, wherein the base portion and the back portion have two struts hingedly connected together at an apex, the hinge being located at or adjacent the free ends of the struts.

6. A folding trolley according to any one of Claims 1 to 4, wherein the back portion is formed by two struts pivotally connected together at an intermediate point thereof and the base portion is formed by two struts hingedly connected together at an apex, the hinge being located at or adjacent the free ends of the struts of the base portions and at or adjacent one free end of each of the struts of the back portion.

7. A folding trolley having a base portion, a back portion connected to the base portion at a hinge, and a linkage adapted to brace the frame in an unfolded position and to fold to permit folding of the trolley, wherein the back portion is formed by two struts pivotally interconnected at an intermediate point thereof and the base portion is formed by two struts hingedly connected together at an apex, the hinge being located at or adjacent the free ends of the struts of the base portion and at or adjacent one free end of each of the struts of the back portion.

8. A folding trolley according to Claim 6 or Claim 7, wherein a plate is pivotally connected to the ends of the struts of the back portion furthest from the hinge, a rigid connection extending between the plates and pivotally connected to each plate, whereby pivoting of said plates on the rigid connection causing pivoting of the struts of the back portion about their interconnection to fold or unfold the trolley.

9. A trolley according to any one of Claims 6 to 8, wherein the hinge includes a bracing strut extending between the connection of the struts of the base and back portions, the bracing strut having at least two parts adapted to hinge relative to each other when the trolley is folded.

10. A trolley according to any one of the preceding Claims, wherein at least some of the wheels are supported in the frame by a hinged mount, the hinged mount being connected to the linkage so that the wheel mounts fold relative to the frame when the frame is folded.

11. A trolley substantially as herein described with reference to and as illustrated in Figs. 1 to 7, or Figs. 8 and 9 of the accompanying drawings.