Abstract: A coupling linking a tractor 10 and a trailer 11 having a fifth wheel assembly 12 having a longitudinal outwardly tapering slot defined by spaced ears 15 is provided with an anti-jackknifing apparatus A, B. Sensor C located adjacent a rear wheel 16 of the trailer generates a frequency reflective of the speed of the tractor and trailer. A radar gun, and the like or other sensor may also be used to determine ground speed. Upon receiving a frequency corresponding to a speed exceeding a predetermined speed, a speed controlled switch D engages the anti-jackknifing apparatus. Similarly, the switch D automatically disengages the apparatus upon receiving a frequency signal corresponding to a speed below the predetermined speed or, upon the occurrence of certain conditions, the activation of a turning signal by the driver. A signal light E mounted externally on the trailer indicates when the apparatus has been activated.

Abstract: A filter for hot melt adhesive is carried within a passageway in a manifold and is rotatable therein between a filtering position in which hot melt adhesive is directed to the inner core of the filter at one end thereof, and a backflushing position in which hot melt adhesive is directed onto the outside surface of the filter at the opposite end thereof. In the filtering position, the hot melt adhesive flows from the inner core outwardly through a filter screen into the main passageway for collection and discharge from one end of the manifold. In the backflushing position the adhesive flow is directed from the outside surface of the filter in the reverse direction through the filter screen to dislodge filtered impurities therefrom, and then the impurities are carried out a drain at the opposite end of the manifold.