CATERPILLAR Russian patent published in 2012 - IPC B62D37/04 B62D49/08 

FIELD: transport.

SUBSTANCE: invention relates to agricultural tractors caterpillar ganged up with tools by means of rear suspension. Proposed tractor comprises frame 1, suspended working tools driven by hydraulic cylinder 3, means for shifting tractor center of pressure including two levers 4 secured at frame front and counterweight arranged on said levers 4. Counterweight is made up of vessel 5 with ballast 6 and arranged to reciprocate on levers 4. Reciprocation is executed by rollers 7 and counterweight hydraulic drive made up of two lateral hydraulic cylinders 8. Like chambers of hydraulic cylinders 3 and 8 are intercommunicated via lines and, via hydraulic control valve 9, with pimp 10 and hydraulic tank 11. Aforesaid vessel 5 is provided with cover 12 for ease of ballast unloading.

EFFECT: required centering of tractor gravity center.

3 dwg