초록 ▼

A trailer including: i) a draw bar; ii) a trailer frame supporting a trailer bed; iii) an arm including a first pivot mount; iv) an axle pivotally connected to the arm at the first pivot mount; v) an actuating mechanism actuatable to exert a force on the arm relative to the trailer frame. The axle i

A trailer including: i) a draw bar; ii) a trailer frame supporting a trailer bed; iii) an arm including a first pivot mount; iv) an axle pivotally connected to the arm at the first pivot mount; v) an actuating mechanism actuatable to exert a force on the arm relative to the trailer frame. The axle includes at least one associated wheel and the wheel has a plane of rotation in which the wheel rotates when traveling in a forward direction, and the actuating mechanism is located substantially in the plane of rotation. The trailer bed may be raised or lowered by exerting a force on the arm relative to the trailer frame.

대표청구항 ▼

1. A trailer comprising: i) a draw bar;ii) a trailer frame supporting a trailer bed;iii) an arm including a first pivot mount;iv) an axle pivotally connected to the arm at the first pivot mount;v) an actuator actuatable to exert a force on the arm relative to the trailer frame;wherein the axle inclu

1. A trailer comprising: i) a draw bar;ii) a trailer frame supporting a trailer bed;iii) an arm including a first pivot mount;iv) an axle pivotally connected to the arm at the first pivot mount;v) an actuator actuatable to exert a force on the arm relative to the trailer frame;wherein the axle includes at least one associated wheel and the wheel has a plane of rotation in which the wheel rotates when traveling in a forward direction, and the actuator is located substantially in the plane of rotation;whereby the trailer bed may be raised or lowered by exerting a force on the arm relative to the trailer frame;wherein the trailer frame includes a second pivot mount, the arm being pivotally movable relative to the trailer frame about the second pivot mount; andwherein the trailer frame includes a third pivot mount located higher than and rearward of the second pivot mount, the actuator pivotally mounted to the third pivot mount and actuatable to exert a force on the arm resulting in rotation of the arm about the second pivot mount. 2. A trailer according to claim 1, wherein the first pivot mount is located inwardly of the wheel. 3. A trailer according to claim 1, wherein the actuator exerts the force on the arm at a location substantially in the plane of rotation. 4. A trailer according to claim 1, wherein the actuator exerts the force on the arm at a location forward of the wheel. 5. A trailer according to claim 1, wherein the actuator exerts the force on the arm at a location rearward of the wheel. 6. A trailer according to claim 1, wherein the arm is pivotally connected to the axle at a location inwardly of the wheel and the actuator acts on a portion of the arm at a location substantially in the plane of rotation. 7. A trailer according to claim 1, wherein the second pivot mount is located substantially in the plane of rotation. 8. A trailer according to claim 1, wherein the actuator exerts the force on the arm at a location forward of the second pivot mount. 9. A trailer according to claim 1, wherein the actuator exerts the force on the arm at a location rearward of the second pivot mount. 10. A trailer according to claim 1, wherein the arm includes at least two portions that are angled relative to each other when projected on the plane of rotation. 11. A trailer according to claim 1, wherein the arm includes at least two portions that are angled relative to each other when projected onto a substantially horizontal plane perpendicular to the plane of rotation. 12. A trailer according to claim 1, wherein the arm includes at least a first section and a second section, the first and second sections being in slideable engagement. 13. A trailer according to claim 1, wherein the trailer frame includes a fixed point located higher than and forward of the second pivot mount, the actuator actuatable to exert a force between the fixed point and the arm, resulting in rotation of the arm about the second pivot mount. 14. A trailer according to claim 13, wherein the fixed point is provided by a bracket. 15. A trailer according to claim 1, wherein the actuator includes a first airbag. 16. A trailer according to claim 1, further comprising a draw bar pivot mount, the draw bar pivotally connected to trailer frame via draw bar pivot mount. 17. A trailer according to claim 1, wherein the actuator includes a first airbag, the trailer further including a draw bar pivot mount, the draw bar pivotally connected to trailer frame via draw bar pivot mount and further including a spring and an air valve, the valve being operable to deflate first airbag and the spring biasing the draw bar towards a towing position. 18. A trailer according to claim 1, wherein the actuator includes a first airbag, the trailer further including a draw bar pivot mount, the draw bar pivotally connected to trailer frame via draw bar pivot mount and further including a draw bar bracket mounted on the draw bar, a connecting bracket mounted on the trailer frame, and a second airbag extending between the draw bar bracket and the connecting bracket, the second airbag when inflated positioning the draw bar in a towing position. 19. A trailer according to claim 18, wherein the first and second airbags include a common first isolating valve and a common venting valve, whereby they are held at a common pressure. 20. A trailer according to claim 1, further comprising brakes associated with the wheel and a safety brake interlock switch operable to prevent the wheel from turning when the draw bar is not in a towing position. 21. A trailer according to claim 1, wherein the draw bar is configured to couple the trailer to a tow vehicle and the trailer bed is configured to be lowered flat to the ground for loading and unloading without decoupling the trailer from the tow vehicle. 22. A trailer comprising: a draw bar;a trailer frame;a wheel carrying structure pivotally connected to the trailer frame and carrying at least one wheel; andan actuator actuatable to exert an at least approximately vertical force on the wheel carrying structure, at a location fore or aft of the pivotal connection between the wheel carrying structure and the trailer frame, to move the trailer frame between a lowered position, in which the trailer frame is in proximity to the ground to be loaded therefrom, and a raised position for towing;wherein the wheel has a plane of rotation in which the wheel rotates when traveling in a forward direction, and the actuator is located substantially in the plane of rotation. 23. A trailer according to claim 22 wherein the actuator exerts the force on the wheel carrying structure at a location forward of the wheel. 24. A trailer according to claim 22 wherein the actuator exerts the force on the wheel carrying structure at a location rearward of the wheel. 25. A trailer according to claim 22 wherein the actuator exerts the force on the wheel carrying structure at a location forward of the pivotal connection pivotally connecting the wheel carrying structure and the trailer frame. 26. A trailer according to claim 22 wherein the actuator exerts the force on the wheel carrying structure at a location rearward of the pivotal connection pivotally connecting the wheel carrying structure and the trailer frame. 27. A trailer according to claim 23 wherein the actuator exerts the force on the wheel carrying structure at a location rearward of the pivotal connection pivotally connecting the wheel carrying structure and the trailer frame. 28. A trailer according to claim 27 further comprising a pivotal connection pivotally connecting the trailer frame and the actuator. 29. A trailer according to claim 22 further comprising a pivotal connection pivotally connecting the trailer frame and the actuator. 30. A trailer according to claim 22 wherein the draw bar is pivotally connected to the trailer frame so as to pivot upwardly relative to the trailer frame from a towing position so that the trailer frame is able to be lowered flat to the ground for loading and unloading without decoupling the trailer from a tow vehicle. 31. A trailer according to claim 30 further comprising a releasable mechanism for rigidly locking the draw bar in its towing position. 32. A trailer according to claim 30 further comprising a further actuator actuatable to drive the draw bar towards the towing position. 33. A trailer according to claim 32 wherein the further actuator is an airbag. 34. A trailer according to claim 22 wherein the actuator is an airbag. 35. A trailer according to claim 28 wherein the actuator is an airbag. 36. A trailer according to claim 34 further comprising an accumulator in communication with each airbag. 37. A trailer according to claim 35 further comprising a further airbag, acting on a further wheel carrying structure, and a valve for selectively isolating the further airbag from the actuator. 38. A trailer comprising: a draw bar;a trailer frame;a wheel carrying structure carrying at least one wheel; andan airbag pivotally mounted to the trailer frame actuatable to exert a force on the wheel carrying structure to raise or lower the trailer frame. 39. A trailer according to claim 38 further comprising an accumulator in communication with the actuator. 40. A trailer according to claim 38 further comprising a pivotal connection pivotally connecting the wheel carrying structure and the trailer frame. 41. A trailer comprising: a draw bar;a trailer frame; andat each side of the trailer a wheel carrying structure carrying at least one wheel; anda pneumatic actuator to exert a force on the wheel carrying structure to raise or lower the trailer frame;wherein each pneumatic actuator is isolated for stability of the trailer while towing. 42. A trailer according to claim 41 further comprising a valve for selectively isolating each pneumatic actuator. 43. A trailer according to claim 41 wherein each pneumatic actuator is an airbag. 44. A trailer according to claim 43 further comprising a respective pivotal connection pivotally connecting the trailer frame and each pneumatic actuator. 45. A trailer according to claim 41 wherein the draw bar is pivotally connected to the trailer frame so as to pivot upwardly relative to the trailer frame from a towing position so that the trailer frame is able to be lowered flat to the ground for loading and unloading without decoupling the trailer from a tow vehicle. 46. A trailer according to claim 45 further comprising a releasable mechanism for rigidly locking the draw bar in its towing position. 47. A trailer according to claim 41 further comprising an accumulator for supplying each pneumatic actuator.