Abstract: A ramp is pivotably mounted in a road bed transverse to the flow of traffic. The ramp pivots between a first position raised above the surface of the road bed and a second position approximately flush with the surface of the road bed, but preferably slightly raised therefrom. A spring biases the ramp to its second position, and applies a return force to the ramp when it pivots from its second, i.e., intermediate, position to a third, i.e., depressed, position substantially flush with the surface of the road bed. Responsive to traffic approaching the ramp from one direction, the ramp pivots from its intermediate position into its depressed position as the traffic passes over the ramp. Responsive to traffic approaching the ramp from the opposite direction, the ramp pivots from its intermediate position into its raised position as the traffic passes over the ramp to signal travel in the wrong direction.

Abstract: A movable linkage has a surface of travel in which a generally V-shaped notch with edges is formed. A rotatable cam follower has first and second sides meeting to form a corner that fits in the notch. One of the sides of the cam follower is urged by a spring against the surface of travel of the linkage. The spring force acts in a direction transverse to one side of the notch and along the other surface of the notch. An arcuate concave relief on the first side of the cam follower adjacent to the corner is shaped to embrace one edge of the notch without such edge bottoming on the cam follower as the corner of the cam follower enters the notch.

Abstract: A movable linkage has a surface of travel in which a generally V-shaped notch with edges is formed. A rotatable cam follower has first and second sides meeting to form a corner that fits in the notch. One of the sides of the cam follower is urged by a spring against the surface of travel of the linkage. The spring force acts in a direction transverse to one side of the notch and along the other surface of the notch. An arcuate concave relief on the first side of the cam follower adjacent to the corner is shaped to embrace one edge of the notch without such edge bottoming on the cam follower as the corner of the cam follower enters the notch.

Abstract: The gear shift stick assembly permits shifting in four forward speeds and reverse. It includes a trigger located near the gear shift knob which may be pulled up or down while the stick is being shifted in position. A wire runs from the trigger down through the stick and engages a generally hat-shaped stop sleeve. When the trigger is not operated, the stop sleeve is in its lower position and abuts a fixed stop member that is mounted in the shift assembly in a position to prevent movement of the stick into the reverse gear-actuating position. If the stick is not in the third-fourth gear slot and the trigger is raised, the stop sleeve comes into the path of another stop member preventing movement of the stick toward the third-fourth gear slot.