Dynamically balanced Gifford-McMahon refrigerator cold head
AssigneeGeneral Electric Company
InventorRobert A. Ackermann
Life of this patent
Estimating the term…
Abstract
A Gifford-McMahon cryorefrigerator is modified by using opposed sub-displacers which are sinusoidally reciprocated in opposite directions with respect to one another such that the force vectors of inertia created by the movement of the sub-displacers are cancelled out. The cancelling out of the force vectors should substantiallly reduce adverse affects associated with displacer banging.
Claims16
An improved cold head for a Gifford-McMahon cryorefrigerator which is comprised of:
- a first thermal station;
- a second thermal station located substantially adjacent said first thermal station;
- a first thermal regenerator;
- a second thermal regenerator located substantially adjacent said first regenerator;
- the improvement comprising
- a drive means;
- and
- at least one displacer means having at least two separate sub-displacer means which are driven by said drive means in a substantially sinusoidal motion to produce an inertial force vector for each said sub-displacer means such that the sum said that inertial force vectors of each said sub-displacer means is substantially completely eliminated.
A Gifford-McMahon cryorefrigeration method for a superconductive magnet having a thermal shield and coils having a cryorefrigerator with a first thermal station, a second thermal station located substantially adjacent said first thermal station, a first thermal regenerator, a second thermal regenerator located substantially adjacent said first thermal regenerator, a drive means, and at least one displacer means having at least two separate sub-displacer means, comprising the steps of:
- contacting said shield with said first thermal station such that heat can be transferred from said shield to said first thermal station;
- contacting said coils with said second thermal station such that heat can be transferred from said coils to said second thermal station;
- contacting said first thermal station with said displacer means so that heat can be transferred from said first thermal station to said displacer means;
- contacting said second thermal station with said displacer means so that heat can be transferred from said second thermal station to said displacer means;
- driving said displacer means in a periodical manner such that said sub-displacers are reciprocated in opposite directions to create varying pressures and volumes between said sub-displacers and force vectors of inertia which should cancel each other out;
- and
- contacting said displacer means with said first and second thermal regenerators so that heat is transferred from said displacer means into said thermal regenerator so that the heat is dissipated.
Dependencies are inferred from the claim text.