Power system for land vehicles

Claim 1

A hydraulically coupled engine comprising: a first piston inside a bored cylinder, valve means for allowing pressurized steam to enter and exit said cylinder, a rod with one end connected to first piston and the other end connected to a solid curvilinear cam shaped block with two contoured surfaces each on a different side of the block and each a reverse curve of the other, each said surface contacting one of a pair of second piston rods at each said second piston rod's end, a pair of second pistons disposed reciprocably inside second opposed cylinders which are fixedly disposed laterally with respect to said block, each said second piston connected to a respective second piston rod for reciprocable movement therewith, said second pistons thereby acting alternately in said opposed cylinders, said second cylinders each being smaller in diameter than said first cylinder and each second cylinder containing hydraulic fluid, a valve means for delivering said hydraulic fluid to a pressure accumulator, a hydraulic motor connected to fluid carrying conduit means at its input side to said pressure accumulator and said motor connected at its output side by fluid carrying conduit means to said second cylinders. wherein said surfaces each have a length substantially equal in length to the stroke length of said first piston and each said surface is curved to form a contact angle φ with the second piston rod which it contacts at any point along the curvilinear block's rectilinear travel substantially according to the formula for the contact angle φ=arc tan (A.sub.s P.sub.s)/(AhPh) in which A s =the circular piston face area of the said first piston, P s =the steam pressure on said first piston face at the position whose contact angle is being calculated, Ah=the circular piston face area of the said respective second piston, and Ph=a selected hydraulic pressure of the respective second cylinder.