Four-Process Cycle for a Vuilleumier Heat Pump

A heat pump, comprising:

• a hot displacer disposed in a hot displacer cylinder;
• a cold displacer disposed in a cold displacer cylinder;
• a housing in which both the hot and cold displacer cylinders are located;
• a hot displacer actuator which when actuated causes the hot displacer to reciprocate between remote and central positions within the hot displacer cylinder;
• a cold displacer actuator which when actuated causes the cold displacer to reciprocate between remote and central positions within the cold displacer cylinder;
• an input signal indicative of the demand for one of heating and cooling;
• and
• an electronic control unit (ECU) receiving the input signal and coupled to the hot displacer actuator and the cold displacer actuator, wherein:
• the ECU commands the hot displacer and cold displacers to move through a series of arrangements:
• a first arrangement in which the hot displacer is at its central position within the hot displacer cylinder and the cold displacer is proximate its central position with the cold displacer cylinder;
• a second arrangement in which the hot displacer is at its remote position within the hot displacer cylinder and the cold displacer is proximate its central position with the cold displacer cylinder;
• a third arrangement in which the hot displacer within the hot displacer cylinder is at its remote position and the cold displacer is proximate its remote position within the cold displacer cylinder;
• a fourth arrangement in which the hot displacer is at its central position within the hot displacer cylinder and the cold displacer is proximate its remote position within the cold displacer cylinder;
• the ECU determines a period of time to command the hot and cold displacers to remain stationary between the first and second arrangements;
• and
• the ECU bases the period of time on the input signal.

A heat pump, comprising:

• a hot displacer disposed in a hot displacer cylinder;
• a cold displacer disposed in a cold displacer cylinder, the hot displacer cylinder and the cold displacer cylinder being coupled together;
• a hot displacer actuator which when actuated causes the hot displacer to reciprocate between remote and central positions within the hot displacer cylinder;
• and
• a cold displacer actuator which when actuated causes the cold displacer to reciprocate between remote and central positions within the cold displacer cylinder;
• an electronic control unit (ECU) electronically coupled to the hot displacer actuator and the cold displacer actuator;
• and
• an input signal indicating demand for one of heating and cooling, the input signal provided to the ECU, wherein:
• ECU actuation of the hot displacer to move from its central position to its remote position comprises process one;
• ECU actuation of the cold displacer to move from its central position to its remote position comprises process two;
• ECU actuation of the hot displacer to move from its remote position to its central position comprises process three;
• ECU actuation of the cold displacer to move from its remote position to its central position comprises process four;
• a cycle comprises:
• process one followed by process two followed by process three followed by process four;
• the ECU commands both displacers to remain stationary for a first period of time between processes one and two;
• the ECU commands both displacer to remain stationary for a second period of time between processes three and four;
• and
• the first and second periods of time are based on the input signal.