| 摘要 |
An automatically retracting tiller for installation at one or both sides of a tractor. A stationary frame is adapted to be secured to a side frame attachment of the tractor. A gimbal frame is pivoted to the stationary frame by a stationary horizontal pivot rod and carries first and second vertical pivot rods. A double-acting vertical hydraulic apparatus has a cylinder secured to the stationary frame and a piston rod secured to the gimbal frame, for tilting the gimbal frame about the horizontal pivot rod. A tiller frame is pivoted to the first vertical pivot rod and carries the tilling apparatus. A double-acting horizontal hydraulic apparatus has a cylinder secured to the stationary frame and a piston rod secured to the tiller frame for swinging the tiller frame about the first vertical pivot bar. A control valve for the horizontal hydraulic apparatus is mounted on the tiller frame and has a control lever. A cam is mounted on the second vertical pivot rod in contact with the control lever for operation of the valve. A spring-released sensor arm is connected to the second vertical pivot rod and extends out horizontally from the gimbal frame so that when it engages a vine or tree trunk or post or grapestake, it rotates the cam and actuates the valve to cause the horizontal hydraulic apparatus to retract the tiller frame and thereby protect the vine trunk from the tilling apparatus. The head is mounted for rotation normally in a horizontal plane and has five depending tines, set at 3 DEG off vertical. A hydraulic motor rotates the tiller head at a speed of about 150-300 r.p.m.
|
