# US 11,028,836 B2 · Drive system comprising at least one metal element exhibiting shape memory properties > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,028,836 B2 - Document ID: US11028836B2 - Status: Granted - Kind: B2 - Application number: 16/652,475 - Filed: 2018-10-01 - Published: 2020-08-27 - Granted: 2021-06-08 - Earliest claimed: 2017-10-05 - Assignees: Bleco-Apparatebau GmbH - Applicants: Bleco-Apparatebau GmbH - Inventors: Werner Patten - Web page: https://patentgrep.com/patent/US11028836B2 ## CPC - F03G 7/06143: {Wires} - F03G 7/0641: {Motors; Energy harvesting or waste energy recovery} - F03G 7/0646: {for pumping or compressing fluids} - F16K 31/002: {actuated by temperature variation (thermo-electric F16K31/025)} - F03G: SPRING, WEIGHT, INERTIA OR LIKE MOTORS; MECHANICAL-POWER PRODUCING DEVICES OR MECHANISMS, NOT OTHERWISE PROVIDED FOR OR USING ENERGY SOURCES NOT OTHERWISE PROVIDED FOR (arrangements in connection with power supply in vehicles from force of nature B60K16/00; electric propulsion with power supply in vehicles from force of nature B60L8/00) - F16K: VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING {(devices for emptying and evacuating the excess liquid in valves or conduits F16L55/07)} ## Abstract A drive system based on cyclic conversion of thermal energy into mechanical or electrical energy by using a difference in temperature between at least two media and the contraction of a metal element with shape memory properties, and a method for generating energy using the drive system. The drive system has a first and a second store containing media at different temperatures, the second store having a passage opening through a bottom of a housing. The housing is a cylinder containing a liquid-tight and gas-tight cylinder piston dividing the cylinder into two cylinder spaces of variable volumes. One cylinder space contains the metal element and the other cylinder space contains a restoring element. The metal element is secured to the piston at a fixing point and to a fixing point within the second store so that the metal element is in contact with the medium of the second store. ## Claims ### Claim 1 A drive system based on the cyclic conversion of thermal energy into mechanical or electrical energy by using a difference in temperature between at least two media (M1, M2) and the contraction of a metal element (20) with shape memory properties, comprising: at least one drive assembly (48, 48′; 49) which comprises a housing (34; 34′) with at least one metal element (20) placed inside the housing (34, 34′), at least one restoring element (37) located inside the housing (34; 34′), and at least one moveable actuating element (35) to which the metal element (20) and the restoring element (37) are coupled, wherein a gaseous or liquid medium flows around the metal element (20) and the restoring element (37), wherein the drive assembly (48, 48′; 49) comprises at least one first and at least one second store (11; 12) containing media (M1, M2) at different temperatures, wherein the second store (12) has a passage opening (36) for direct connection of the second store (12) with a first cylinder space (14) through a bottom (18) of the housing (34, 34′), the housing (34, 34′) is a cylinder (10) which contains a liquid- and gas-tight arranged cylinder piston (15) and wherein the cylinder piston (15) forms the actuating element (35), and the cylinder piston (15) divides the cylinder (10) into the first cylinder space (14) and a second cylinder space (16), wherein the two cylinder spaces (14, 16) are separated from each other by the cylinder piston (15), and wherein the first cylinder space (14), which is bounded by the bottom (18), contains the metal element (20) with shape memory properties, and the second cylinder space (16) contains the restoring element (37), wherein the metal element (20) is secured to the cylinder piston (15) at a fixing point (A) on the cylinder piston (15) and to a fixing point (B) located within the second store (12) so that a section (33) of the metal element (20) is in contact with the medium (M2) of the second store (12) and a section (39) is in contact with the medium (M1) in the second store (14). ### Claim 2 (depends on 1) The drive system as claimed in claim 1, wherein the first store (11) is connected via a first pipe (19) to the second cylinder space (16) containing the restoring element (37), wherein at least one first valve (21, 21′) is installed in the pipe (19), and the first store (11) is connected via a second pipe (22) to the first cylinder space (14) containing the metal element (20), wherein at least one second valve (23) is installed in the pipe (22). ### Claim 3 (depends on 2) The drive system as claimed in claim 2, wherein the cylinder space (14) is connected via a further pipe (40) to a third store (44), wherein the third store (44) is provided for receiving a gaseous or liquid medium (M3), so that when the third medium (M3) has a temperature (T3) which is lower than the temperature (T1) of the medium (M1) and higher than the temperature (T2) of the medium (M2), the part of the metal element (20) located in the cylinder chamber (14) is preheated when the cylinder piston (15) moves in the direction (R2) and the stroke frequency and thus the power of the drive system is increased as a result. ### Claim 4 (depends on 2) The drive system as claimed in claim 2, further comprising a valve controller (26) which controls the first valve (21, 21′) by a stroke of a piston rod (13) connected directly or indirectly to the cylinder piston (15). ### Claim 5 (depends on 2) The drive system as claimed in claim 2, wherein the restoring element (37) is a spring (17). ### Claim 6 (depends on 1) The drive system as claimed in claim 1, wherein the cylinder piston (15) is a hollow body (52) which includes at least one valve (21′; 60, 61). ### Claim 7 (depends on 2) The drive system as claimed in claim 2, wherein the first store (11) is arranged within the second cylinder space (16). ### Claim 8 (depends on 2) The drive system as claimed in claim 2, wherein the restoring element (37) is formed by the piston rod (13) and a cable connection (46, 46′) coaxially connected to the piston rod (13), wherein the cable section (46, 46′) is moveable in translation up to a deflection roller (47, 47′). ### Claim 9 (depends on 1) The drive system as claimed in claim 1, wherein the medium of the stores is liquid or gaseous. ### Claim 10 (depends on 9) The drive system as claimed in claim 9, wherein the media of the stores are immiscible with each other and/or have different specific weights. ### Claim 11 (depends on 1) The drive system as claimed in claim 1, wherein at least one store is thermally insulated. ### Claim 12 (depends on 1) The drive system as claimed in claim 1, wherein a plurality of the drive systems are coupled to one another and the movement of the cylinder pistons (15) is coordinated by a control device. ### Claim 13 (depends on 1) The drive system as claimed in claim 1, wherein an upper and/or a lower final position control of the cylinder pistons (15) is provided as the control device. ### Claim 14 A method for generating energy by converting heat into mechanical or electrical energy in a closed drive system, comprising: providing housing (34, 34′) in the form of a cylinder (10); providing a cylinder piston (15) in the cylinder, wherein the cylinder piston (15) divides the cylinder (10) into a first cylinder space (14) and a second cylinder space (16), wherein the two cylinder spaces (14, 16) are separated from each other by the cylinder piston (15); placing a metal element (20) in the cylinder (10), wherein the metal element (20) is attached to the cylinder piston (15) and extends through the first cylinder space (14), and wherein the metal element (20) has shape memory properties; providing a restoring element (37) in the cylinder (10), wherein the restoring element (37) is attached to the cylinder piston (15) and extends through the second cylinder space (16); and subjecting the metal element (20) to uniaxial contraction by applying a temperature difference (T1) and (T2), between two respective media (M1) and (M2), to the metal element (20), wherein the temperature difference (T1) and (T2) between the two respective media (M1) and (M2) is maintained by a cyclical pumping process, which is realized by a reciprocating action of the cylinder piston (15) to which the metal element (20) is attached, whereby the temperature difference (T1) and (T2) causes the metal element (20) to contract and to move the cylinder piston (15) in a first direction (R1) and the restoring element (37) subsequently causes the cylinder piston (15) to move in a second direction (R2) opposite the first direction (R1) thereby creating the reciprocating action of the cylinder piston (15), and wherein the pumping process is controlled by actuating a valve controller (26) by the stroke of a piston rod (13) provided on the cylinder piston (15). ### Claim 15 (depends on 14) The method as claimed in claim 14, wherein the heat involved is waste heat. ### Claim 16 (depends on 15) The method as claimed in claim 15, wherein the waste heat is generated by a combustion engine or an exothermic chemical plant. ### Claim 17 (depends on 5) The drive system as claimed in claim 5, wherein the spring (17) is a tensioning spring. ### Claim 18 (depends on 13) The drive system as claimed in claim 13, wherein the control device comprises a spring-supported locking bolt (61) for fixing the upper and/or the lower final position control of the cylinder pistons (15).