| 摘要 |
A folding ramp comprises a first 10 and a second 20 section, the first being pivotally mounted relative to a vehicle or trailer when in use and the second being pivotally mounted relative the opposing end of the first section. A control mechanism to control the movement of the ramp comprises three arms. The first 51 and second 52 arm each have one end pivotally attached to the first and second ramp sections respectively and the third arm 53 is pivotally connected to a mounting bracket 55. The free ends of the three arms are pivotally connected together. The reaction of the third arm against the mounting bracket as the first ramp section is lowered exerts a force on the second arm which rotates the second ramp section about the first ramp section and deploys the second ramp section outwardly from the first ramp section. The lowering mechanism is a double acting hydraulic ram. The connection between the free ends of the three arms may be a clevis joint. Preferably the third arm has a screw threaded adjustment means to change the length of the third arm. |
