Shock-absorbing push-pull coupling for tandem scrapers

In a push-pull coupling for a tandem arrangement of tractor-scraper units wherein a first coupling section is provided which includes a first push block formed at the rear of one tractor-scraper unit and a pulling hook fixedly mounted over said first push block, the combination of said first coupling section with a second coupling section arranged on the front of the other tractor-scraper unit which includes tractor framework, said second coupling section comprising, in combination:

• support means secured to said tractor framework on the front of said other tractor-scraper unit;
• a second push block pivotally supported at its top end by said support means and adapted for contact with said first push block to establish a pushing relation between the tractor-scraper units;
• a bail pivotally connected to said second push block at the bottom end of the latter and adapted for engagement of said pulling hook to establish a pulling relation between the tractor-scraper units;
• two-way shock-absorber means arranged between the bottom end of said second push block and said tractor framework, said two-way shockabsorber means being dually effective to lessen the shock caused upon contact between said first and second push blocks and upon engagement of said pulling hook by said bail, and
• means for limiting the pivotal motion of said second push block upon engagement with said first push block in either a pushing or pulling operation.