초록 ▼

A trolley includes a front wheel assemblie (12) and a rear wheel assembly both assemblies mounted on a trolley frame. The front wheel assembly (12) includes a fixed wheel assembly (24) to aid control of the trolley. In one form the front wheel assembly (12) includes a pair of swivel castors (18) and

A trolley includes a front wheel assemblie (12) and a rear wheel assembly both assemblies mounted on a trolley frame. The front wheel assembly (12) includes a fixed wheel assembly (24) to aid control of the trolley. In one form the front wheel assembly (12) includes a pair of swivel castors (18) and a fixed wheel assembly (24) disposed between the castors (18). The front wheel assembly (12) is designed so that when the castors (18) swivel from their orientation for forward travel, the fixed wheel assembly (24) is caused to be lifted off the ground. The trolley also includes a camming device which is operative to lift the front wheel assembly (12) off the ground when the trolley is moved into a nested configuration with a like trolley.

대표청구항 ▼

The invention claimed is: 1. A trolley comprising: a trolley frame; front and rear wheel assemblies, one of the front and rear wheel assemblies including a pair of casters; each of the pair of casters having a first axis and a second axis transverse to the first axis and including a yoke mounted to

The invention claimed is: 1. A trolley comprising: a trolley frame; front and rear wheel assemblies, one of the front and rear wheel assemblies including a pair of casters; each of the pair of casters having a first axis and a second axis transverse to the first axis and including a yoke mounted to the trolley frame in a manner that allows the caster to swivel about the first axis, and a caster wheel mounted to the yoke so as to be rotatable about the second axis, each of the pair of casters being operative to adopt a first orientation for forward travel of said trolley; and a fixed wheel assembly located between said pair of casters, said fixed wheel assembly including at least one wheel which has an axis of rotation which is orientated so that said fixed wheel assembly assists in maintaining directional control of said trolley in its forward travel, wherein the trolley frame is caused to lift on swiveling of the casters from their first orientation by having the centre of the caster wheels radially displaced from their first axes and having the first axes inclined to the vertical and extending rearwardly of the trolley and the at least one wheel of the fixed wheel assembly is positioned to engage the ground when the castors are in their first orientations and to be off the ground on swivelling of the casters about their first axes from their first orientations. 2. A trolley according to claim 1, wherein the fixed wheel assembly is disposed between the casters. 3. A trolley according to claim 1, wherein the wheel assembly including the pair of casters is the front wheel assembly. 4. A trolley according to claim 3, wherein the wheel of the fixed wheel assembly is aligned with the casters of the front wheel assembly. 5. A trolley according to claim 3, wherein the fixed wheel assembly is displaced either forward or rearward of the casters of the front wheel assembly. 6. A trolley according to claim 1, wherein the other of the front and rear wheel assemblies also includes a pair of casters, each caster having a first axis and a second axis transverse to the first axis and including a yoke mounted to the trolley frame in a manner that allows the caster to swivel about the first axis, and a caster wheel mounted to the yoke so as to be rotatable about the second axis, each of the pair of casters of the other wheel assembly being operative to adopt a first orientation for forward travel of said trolley. 7. A trolley according to claim 1, wherein the fixed wheel assembly is the form of a fixed caster including a yoke mounted to the trolley frame, and a caster wheel rotatably mounted to the yoke. 8. A trolley according to claim 1, wherein the trolley is designed to be nested with another said trolley, wherein the front portion of one trolley is in overlapping relation with the rear portion of the other trolley, and wherein the trolley further comprises lifting means which is operative to cause the wheels of the front wheel assembly of the one trolley to be lifted off the ground on nesting of the two trolleys. 9. A trolley according to claim 8, wherein the lifting means is in the form of complementary surfaces arranged to interengage during nesting of the trolleys. 10. A trolley according to claim 9, further comprising a camming device which includes a camming surface, the camming device being secured to the trolley so that the camming surface forms one of the complementary surfaces and engages a surface of the other trolley on nesting of the trolleys. 11. A trolley according to claim 10, wherein the trolley further comprises a basket having a rear gate, and wherein on nesting, the basket of the one trolley locates in the basket of the other trolley through the rear gate, and wherein the camming surface is positioned so as to engage a surface of the basket to cause lifting of the one trolley. 12. A trolley according to claim 11, wherein the camming device is mounted on a base surface of the basket and projects downwardly therefrom. 13. A trolley according to claim 11, wherein the camming device is mounted to a base of the basket and projects upwardly therefrom. 14. A trolley according to claim 10, wherein the camming device comprises an elongate member having opposite ends and being profiled to form the camming surface intermediate the ends, the member further comprising engagement elements located at each end which are arranged to be fixed to the basket of said trolley. 15. A trolley according to claim 14, wherein the basket of the trolley is formed from wire mesh and the engagement elements are in the form of eyelets which are operative to engage respective wire bars of the trolley basket. 16. A trolley comprising: a trolley frame; a basket having a rear gate mounted on the trolley frame; front and rear wheel assemblies, the front wheel assembly including a pair of casters; each of the pair of casters having a first axis and a second axis transverse to the first axis and including a yoke mounted to the trolley frame in a manner that allows the caster to swivel about the first axis, and a caster wheel mounted to the yoke so as to be rotatable about the second axis with the centre of the caster wheel being radially displaced from the first axis, each of the pair of casters being operative to adopt a first orientation for forward travel of said trolley; a fixed wheel assembly located between said pair of casters, said fixed wheel assembly including at least one wheel which has an axis of rotation which is orientated so that said fixed wheel assembly assists in maintaining directional control of said trolley in its forward travel; and a camming device which includes a camming surface; wherein the trolley is arranged to be nested with another said trolley where the basket of one trolley locates in the basket of the other trolley through the rear gate and wherein the camming surface is positioned so as to engage a surface of the basket of said other trolley to causing lifting of the one trolley. 17. A trolley according to claim 10, wherein the camming device comprises an elongate member having opposite ends and being profiled to form the camming surface intermediate the ends, the member further comprising engagement elements located at each end which are operative arranged to be fixed to the basket of said trolley. 18. A trolley according to claim 14, wherein the basket of the trolley is formed from wire mesh and the engagement elements are in the form of eyelets which are operative to engage respective wire bars of the trolley basket.