Solid state heat engine

A compound solid state heat engine comprising:

• a source of thermal energy;
• a sink for thermal energy;
• a first solid state heat engine having a first energy transferring medium, a first driven means and a first driver means, said first driven and driver means for mechanically coupling with said first energy transferring medium and for translating force exerted by said first energy transferring medium into a force exerted by said first driven and first driver means, said first energy transferring means thermally being coupled to said source and sink respectively;
• a second solid state heat engine having a second energy transferring medium, a second driven means and a second driving means, said second driven and second driver means for mechanically coupling with said second energy transferring medium and for translating force exerted by said second energy transferring medium into a force exerted by said second driven and second driver means, said second energy transferring means being thermally coupled to said source and sink;
• coupling means for coupling said first driven means to said second driver means and for coupling said second driven means to said first driver means, whereby said first and second solid state heat engines are cooperatively paired to provide an increased power output;
• and
• wherein at least one of said first and second driven and driver means includes a variable radius pulley having a temporally varying radius in each angular direction with respect to a frame of reference rotating at the same angular velocity as said variable radius pulley and having a temporally constant radius in each angular direction with respect to a fixed, nonrotating frame of reference, said constant radius differing in magnitude in each said angular direction with respect to said fixed, nonrotating frame of reference.

A compound solid state heat engine comprising:

• a plurality of heat sources and sinks arranged in a first and second symmetric half, a heat source in said first half being juxtaposed next to a heat sink in said second half;
• a heat sink in said first half being juxtaposed to a heat source in said second half, said heat sources and sinks being alternately disposed within each said first and second halves;
• a plurality of idler rollers, one of said plurality of idler rollers being disposed in each one of said plurality of heat sources and sinks;
• a plurality of driven rollers and drivers rollers, each driven roller of said plurality associated with one of said first and second halves and coupled to a driver roller of said plurality associated with said other one of said first and second halves, each said driven roller in one of said halves separated an essentially fixed distance from the driver roller associated into the same said half;
• and
• a first and second plurality of thermally responsive solid state shape memory alloy members exhibiting a joule effect contraction upon heating, said members coupled to said plurality of idler, driven and driver rollers, said first plurality being coupled to said rollers associated with said first half, and said second plurality being coupled to said rollers associated with said second half, said first and second plurality of solid state members being urged by said plurality of idler rollers into thermal contact with said plurality of heat sources and sinks;
• wherein said first plurality of solid state members is operatively paired with said second plurality of solid state members;
• wherein said first and second plurality of solid state members includes a snubber coupled thereto for limiting the strain of said solid state members;
• whereby a compact solid state engine is devised having an increased power output.

A method for converting thermal energy to mechanical energy in a solid state engine comprising the steps of:

• continuously coupling thermal energy into a first solid state shape memory alloy member from a heat source to obtain a first type of mechanical response therefrom, said first type of mechanical response including a joule effect contraction;
• continuously coupling said first type of mechanical response from said first solid state member to a first driver pulley to exert a first type of torque thereon;
• continuously coupling thermal energy from said first solid state member into a heat sink to obtain a second type of mechanical response therefrom, said second type of mechanical response including a joule effect expansion;
• continuously coupling said second type of mechanical response from said first solid state member to a first driven pulley a fixed distance from said first driver pulley to exert a second type of torque thereon;
• continuously coupling thermal energy into said heat sink from a second solid state shape memory alloy member to obtain said second type of mechanical response therefrom;
• continuously coupling said second type of mechanical response from said second solid state member to a second driven pulley a fixed distance from a second driver pulley to obtain said second type of torque, said first driver pulley and said second driven pulley being coupled, said torque applied to said second driven pulley exceeding said torque applied to said first driver pulley;
• continuously coupling thermal energy from said heat source to said second solid state member to obtain said first type of mechanical response therefrom;
• continuously coupling said first type of mechanical response from said second solid state member to said second driver pulley to exert said first type of torque thereon, said second driver pulley being coupled to said first driven pulley, said torque applied to said first driven pulley exceeding said torque applied to said second driver pulley;
• wherein at least one of said first and second types of mechanical responses is limited by a snubber;
• whereby a compact compound solid state engine may be devised with increased power.

A method for converting thermal energy to mechanical energy in a solid state engine comprising the steps of:

• continuously coupling thermal energy into a first solid state shape memory alloy member from a heat source to obtain a first type of mechanical response therefrom, said first type of mechanical response including a joule effect contraction;
• continuously coupling said first type of mechanical response from said first solid state member to a first driver pulley to exert a first type of torque thereon;
• continuously coupling thermal energy from said first solid state member into a heat sink to obtain a second type of mechanical response therefrom, said second type of mechanical response including a joule effect expansion;
• continuously coupling said second type of mechanical response from said first solid state member to a first driven pulley a fixed distance from said first driver pulley to exert a second type of torque thereon;
• continuously coupling thermal energy into said heat sink from a second solid state shape memory alloy member to obtain said second type of mechanical response therefrom;
• continuously coupling said second type of mechanical response from said second solid state member to a second driven pulley a fixed distance from a second driver pulley to obtain said second type of torque, said first driver pulley and said second driven pulley being coupled, said torque applied to said second driven pulley exceeding said torque applied to said first driver pulley;
• continuously coupling thermal energy from said heat source to said second solid state member to obtain said first type of mechanical response therefrom;
• and
• continuously coupling said first type of mechanical response from said second solid state member to said second driver pulley to exert said first type of torque thereon, said second driver pulley being coupled to said first driven pulley, said torque applied to said first driven pulley exceeding said torque applied to said second driver pulley;
• wherein at least one of said first and second driven and driver pulleys is a variable radius pulley having a radius varying time in each angular directions with respect to a frame of reference rotating at the same angular velocity as said at least one pulley and having a radius constant in time in each angular direction with respect to a fixed, nonrotating frame of reference, said constant radius differing in magnitude in each said angular direction with respect to said fixed, nonrotating frame of reference;
• whereby a compact compound solid state engine may be devised with increased power.

A compound solid state heat engine comprising:

• A plurality of continuous loops of shape memory alloy material which undergoes a joule effect contraction upon heating to an elevated liquid water temperature;
• banks of alternating hot and cold water baths at temperatures providing joule effect contraction of said alloy material at the hot bath temperature and lower energy stretchability of said alloy material at the cold bath temperature;
• an array of driving, driven and idler rollers on parallel axes leading said loops of alloy material in parallel planes sequentially through cold water baths, stretching the alloy material at the lower temperature at the driven rollers, and then leading said loops into the hot water baths and taking energy from the contraction of said alloy material at the hot bath temperature at the driving rollers, whereby each loop of said alloy material is subjected to multiple cycles of stretching and contraction in each traverse through said banks;
• and means coupling the driving and driven rollers whereby the energy for stretching the said alloy material at the lower temperature is provided from the driving rollers.

A compound solid state heat engine comprising:

• a first half and a second half each of said halves having:
• (a) a plurality of continuous loops of shape memory alloy material which undergoes a joule effect contraction upon heating to an elevated liquid water temperature;
• (b) a plurality of sources of thermal energy at a temperature sufficiently elevated to produce the joule effect contraction of said shape memory alloy material;
• (c) a plurality of sinks for thermal energy at a sufficiently lower temperature than said sources of thermal energy to permit stretching of said shape memory alloy material by a force substantially less than the force of the joule effect contraction of said material at the temperature of said sources of thermal energy;
• (d) said sources and sinks of thermal energy being arrayed alternately along the paths of said loops of shape memory alloy material and the sources and sinks for said first and second halves of the engine being arrayed whereby each source of thermal energy in the first half is positioned opposite a sink in the second half;
• (e) first means in each of said halves for continuously moving said loops of shape memory alloy material in heat exchange with said sinks for thermal energy and stretching said material at the lower temperature;
• (f) second means in each of said halves for continuously moving said loops of shape memory alloy material in heat exchange with said sources of thermal energy and converting the force of the contractions of said material at the elevated temperature to rotational force;
• (g) and rigid coupling means drivingly connecting the first and second halves of the engine whereby rotational force developed by the contractions of said alloy material in one half is transmitted to the means for stretching the alloy material in the other half.