The invention relates to a heat engine (29), including a drive unit (1) provided with: a casing (2) delimiting therein an annular chamber (12), two triads of pistons (7a-7b-7c; 9a-9b-9c) rotatably housed in the casing of the annular cylinder (or toroidal cylinder), a three-shaft movement system (18) configured to transmit motion from and/or to the two triads of pistons; wherein the heat engine is configured so as to carry out a Rankine or Rankine-Hirn thermodynamic cycle, capable of producing electrical energy and heat; the same invention further relates to a pneumatic motor (61) including the aforesaid drive unit (1), configured so as to transform the compressed air at high pressure, contained in a tank, into mechanical energy.

The invention relates to a heat engine (29), including a drive unit (1) provided with: a casing (2) delimiting therein an annular chamber (12), two triads of pistons (7a-7b-7c; 9a-9b-9c) rotatably housed in the casing of the annular cylinder (or toroidal cylinder), a three-shaft movement system (18) configured to transmit motion from and/or to the two triads of pistons; wherein the heat engine is configured so as to carry out a Rankine or Rankine-Hirn thermodynamic cycle, capable of producing electrical energy and heat; the same invention further relates to a pneumatic motor (61) including the aforesaid drive unit (1), configured so as to transform the compressed air at high pressure, contained in a tank, into mechanical energy.

A scroll compressor includes an orbiting scroll including an end plate and a spiral element on the end plate, a fixed scroll including an end plate and a spiral element on the end plate, and an Oldham ring including a support. The scroll compressor satisfies a relation of 1>2, where 1 denotes each of the axial length of a gap between the tip of the spiral element of the orbiting scroll and the end plate of the fixed scroll and a gap between the tip of the spiral element of the fixed scroll and the end plate of the orbiting scroll, and 2 denotes the axial length of a gap between the end plate of the orbiting scroll and the support of the Oldham ring.

A scroll compressor includes an orbiting scroll including an end plate and a spiral element on the end plate, a fixed scroll including an end plate and a spiral element on the end plate, and an Oldham ring including a support. The scroll compressor satisfies a relation of 1>2, where 1 denotes each of the axial length of a gap between the tip of the spiral element of the orbiting scroll and the end plate of the fixed scroll and a gap between the tip of the spiral element of the fixed scroll and the end plate of the orbiting scroll, and 2 denotes the axial length of a gap between the end plate of the orbiting scroll and the support of the Oldham ring.

A magnetically engaged pump includes a pump housing with a rotatable magnetic drive assembly, a cylindrical canister and a rotatable driven magnet assembly. This magnetic coupling is associated with a pump rotor and a laterally positioned gear wheel to define a gear pump. This magnetic coupling is alternatively associated with a pump rotor with an impeller to define a centrifugal pump. Either pump includes a stationary shaft to mount the driven magnet assembly and pump rotor. A rotatable carrier with bushings and thrust bushings coaxially supports the rotatable driven magnet assembly and pump rotor.

A magnetically engaged pump includes a pump housing with a rotatable magnetic drive assembly, a cylindrical canister and a rotatable driven magnet assembly. This magnetic coupling is associated with a pump rotor and a laterally positioned gear wheel to define a gear pump. This magnetic coupling is alternatively associated with a pump rotor with an impeller to define a centrifugal pump. Either pump includes a stationary shaft to mount the driven magnet assembly and pump rotor. A rotatable carrier with bushings and thrust bushings coaxially supports the rotatable driven magnet assembly and pump rotor.

A magnetically engaged pump includes a pump housing with a rotatable magnetic drive assembly, a cylindrical canister and a rotatable driven magnet assembly. This magnetic coupling is associated with a pump rotor and a laterally positioned gear wheel to define a gear pump. This magnetic coupling is alternatively associated with a pump rotor with an impeller to define a centrifugal pump. Either pump includes a stationary shaft to mount the driven magnet assembly and pump rotor. A rotatable carrier with bushings and thrust bushings coaxially supports the rotatable driven magnet assembly and pump rotor.

A magnetically engaged pump includes a pump housing with a rotatable magnetic drive assembly, a cylindrical canister and a rotatable driven magnet assembly. This magnetic coupling is associated with a pump rotor and a laterally positioned gear wheel to define a gear pump. This magnetic coupling is alternatively associated with a pump rotor with an impeller to define a centrifugal pump. Either pump includes a stationary shaft to mount the driven magnet assembly and pump rotor. A rotatable carrier with bushings and thrust bushings coaxially supports the rotatable driven magnet assembly and pump rotor.

One embodiment may include a rotary engine, whose cylinder is in doughnut-shape. A cross-section of the cylinder is circular. The engine includes a pair of rotation disks, a power disk and passive disk. A power-output shaft is coaxial with an axis of the cylinder. A power piston and passive piston rotate around an axis of the power-output shaft. A space between the power piston in front and the passive piston at the back is a working chamber. When combustion and expansion take place in the working chamber, the power piston will be pushed forward continuously by the expanding gases, and output power via the power-output shaft. The passive piston relies on a driving system to drive it moving forward. Volume of the working chamber varies within one revolution of rotation. Larger volume of the working chamber causes combustion and expansion. Smaller volume of the working chamber causes compression and emission.

A mechanical link (100, FIG. 5), the mechanical link comprising a first arm (120), a second arm (140) and an interconnection member (160), wherein: the first arm is rotatable about a first axis of the interconnection member; the second arm is rotatable about a second axis of the interconnection member, the second axis being orthogonal to the first axis; and wherein: a flexible member (400) extends along the first and second arms and is adapted to accommodate rotation of the arms about the first and second axes, the flexible member having a single coiled portion (440) which is received within the interconnection member such that the coiled portion can coil and uncoil to accommodate rotation of the first arm, wherein the coiled portion is further configured to twist about an axis of the flexible member to accommodate rotation of the second arm.