Abstract: A trailer convertible to a sled uses a drop axle, which is mounted for rotation. The drop axle has a sled mode and a trailer mode. Upon rotation of a primary shaft of the drop axle in a first direction, ski supports lower skis into the sled mode and secondary shafts supporting wheels are raised. Upon rotation of the primary shaft of the drop axle in a second direction, the ski supports raise the skis and the secondary shaft supporting wheels are lowered to the trailer mode. A lock is provided for locking the drop axle in a selected one of the sled mode or the trailer mode.

Abstract: An elevated hunting blind includes a frame and an observatory supported by the trailer. Rigid travel guides extend upwardly from the frame providing a travel path. A drive system is provided for moving the observatory along the travel path provided by the travel guides to raise the observatory from a transport to an observation position.

Abstract: A release mechanism for a hydraulic/pneumatic post driver is described. The post driver has a hammer and a guide for directing the hammer from a raised release position along a substantially vertical downward impact path. A hydraulically or pneumatically actuated fluid expandable cylinder is disposed above the hammer and has a telescopically extendible piston for lifting the hammer to the raised release position. The improvement includes one of the piston and the hammer having a female member with inwardly directed gripping dogs. The other of the piston and the hammer has a male member with outwardly directed gripping rollers. One of the inwardly directed gripping dogs and the outwardly directed gripping rollers is spring biased to maintain engagement between the dogs and rollers. A triggering mechanism is provided on the guide to overcome the biasing force of the spring to disengage the dogs and the rollers when the hammer reaches the raised release position.

Abstract: An improvement in a rock picking machine having a frame with ground wheels supporting the frame, a table with a grate over which rocks are moved and discharged into a bucket rearwardly pivotally mounted on the frame, and a conveyer forwardly pivotally mounted on the table for moving rocks up the grate. The improvement consists of at least one forwardly and upwardly extending member positioned at a rearward end of the conveyer frame. The member forms a wedge shaped cavity. As large rocks are moved up the grate by the conveyer through the wedge shaped cavity, the rocks engage the member thereby lifting the rearward end of the conveyer frame to provide clearance.

Abstract: A windrow mover having a frame with a linkage arm on each side. Each of the linkage arms having a first end pivotally attached near the front of and at a point on the axis of the frame. An axle is attached to a second end of each linkage arm defining an axis. Ground engaging wheels are mounted on each of the axles, thereby permitting movement of the frame over a groundsurface. A hydraulic cylinder is provided for moving the linkage arm such that the axis of the frame moves in a substantially vertical plane radially about the axis of the wheels as defined by the axle, thereby altering the spacial relationship between the frame and the wheels from an operative position where the front of the frame is adjacent the groundsurface to a transport position where the front of the frame is spaced from the groundsurface.