Application of Paul Hollis Taylor

288 F.2d 950, 48 C.C.P.A. 904
CourtCourt of Customs and Patent Appeals
DecidedApril 14, 1961
DocketPatent Appeal 6618
StatusPublished
Cited by2 cases

This text of 288 F.2d 950 (Application of Paul Hollis Taylor) is published on Counsel Stack Legal Research, covering Court of Customs and Patent Appeals primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Application of Paul Hollis Taylor, 288 F.2d 950, 48 C.C.P.A. 904 (ccpa 1961).

Opinion

RICH, Judge.

This appeal is from the decision of the Patent Office Board of Appeals affirming the examiner’s rejection of method claims 22 and 23 in application Ser. No. 409,341, filed February 10, 1954, entitled “Accumulator.” Nine claims, each drawn to an “accumulator system,” have been allowed by the examiner.

The invention of the appealed claims is predicated on recognition of the fact that energy can be stored upon compression of certain liquids and solids by reason of their polymorphic transition and that the stored energy can be released to perform work. When subjected to sufficiently high pressures, certain materials undergo changes in form resulting in sudden change in volume, the change in volume occurring gradually as pressure is increased until a critical pressure is reached, at which point a relatively large volumetric change may take place in response to a relatively small pressure change. This larger change in volume at a substantially constant pressure is known as a polymorphic transition. Additionally, the polymorphic transition phenomenon must be reversible so that a previously compressed material will return to its initial higher-volume state in response to pressure reduction. This expansion of- the material attendant upon the pressure decrease is the source of energy that appellant uses to perform work.

To illustrate, one of the materials disclosed by appellant is silver iodide which he says abruptly compresses, at a constant pressure of 42,600 pounds per square inch, from the 1.1% reduction in volume it has then undergone as pressure rose from zero to a reduction in volume of 17.4%. This, appellant says, is a volume reduction of 16.3% under substantially constant pressure conditions. Upon slight reduction from the transition pressure the volume returns to what it was. Appellant, however, makes no claim to the discovery of this phenomenon, but attributes it to Professor P. W. Bridgman of Harvard University, author of the references.

Claims 22 and 23 are substantial duplicates, each reciting three basic steps. We have broken claim 23 into its three basic steps for purposes of discussion. It reads:

“A method of storing and utilizing energy in a work performing system through the medium of a non-gaseous material capable of polymorphic transition at a substantially constant pressure, comprising the steps of
“[A] reducing the volume of the non-gaseous material at substantially said constant pressure to cause polymorphic transition to thereby store energy,
“[B] subsequently reducing the pressure on said non-gaseous material below said constant pressure to cause reverse polymorphic transition to thereby expand the material, and
“[C] concomitantly applying the energy of expansion of the material to work performing means in said system.”

The application discloses specific accumulator devices so constructed as to utilize the energy released by expanding, previously-compressed, polymorphic transition materials. Accumulators, in general, are devices which store me *952 chanical energy to supply peak demands and provide pressure leveling in hydraulic systems, and commonly use compressed gases as the energy storage medium. Each of appellant’s accumulators has a heavy-walled compression chamber, containing a polymorphic transition material, connected to a hydraulic system. Pressure changes in the hydraulic system are transmitted from the hydraulic fluid to the compressible material. The accumulator is charged, i. e., the material is compressed to its lower-volume state, by the static pressure in the accompanying hydraulic system, or by pressure from an external source. It can be charged readily by such means as a conventional hand pump, and it may be stored in a charged condition indefinitely, so appellant says. In each instance, when the charging pressure drops below the critical transition value, the expanding material either pushes a piston, or a flexible diaphragm, or acts directly on the hydraulic fluid, in the case where it is in direct contact therewith, exerting sufficient force to do substantial work.

Various advantages are said to flow from the utilization of accumulators having polymorphic transition material as the energy storage medium, such as an increased amount of available energy for a given volumetric change; weight, size and cost reductions; and the release of energy at a substantially constant pressure.

The examiner, in his final rejection, and the board in affirming that rejection, relied on three references which were made of record by appellant. They are:

“Bridgman — Proceedings of American Academy of Arts and Sciences — Volume 76, No. 1, pages 2-7, February 1945.
“Bridgman — Proceedings of the American Academy of Arts and Sciences — Volume 76, No. 3, pages 71-87, March 1948.
“Bridgman — Proceedings of the American Academy of Arts and Sciences — Volume 77, No. 4, pages 127-128, 131-134, February 1949.”

The references disclose an extensive series of compressibility tests on a wide variety of liquids and solids, including test results in tabular and graphic form and a general discussion of the test results. The articles amply testify to Professor Bridgman’s recognition of the compressibility of certain solids and liquids and of the fact that this compression may include a polymorphic transition. Professor Bridgman’s experiments included testing silver iodide, one of applicant’s preferred materials, and in Volume 76, February 1945, at page 5, a graph of volume decrements for certain iodides shows an easily recognizable large polymorphic transition for that material.

Generally speaking, Professor Bridgman’s test results were obtained by applying incremental pressure increases and taking corresponding volume readings for each pressure increase after allowing sufficient time for any heat of compression to dissipate. Decreasing pressure runs were also made. While the exact procedure for each of the tests is not disclosed, Professor Bridgman, at one point, indicates that 43 readings for both increasing and decreasing pressures were taken and throughout the articles it is notéd that the difference, at corresponding pressures, between volume readings for increasing and decreasing pressures, was consistently small.

While the test equipment used for the earlier experiments is not thoroughly described in the articles, the February 1949 article illustrates and describes a later used testing device. That device has a heavy steel cylinder in which is placed the material whose compressibility is to be measured. Pressure is applied to the material by a piston and the article says that change in volume is “given directly by the motion of the piston measured by a dial guage graduated to 0.001 inch and reading by estimation to 0.0001 inch.” The piston which is in direct contact with the material is driven by a larger force-multiplying piston which in turn is driven by a conventional hand pump connected to the larger piston through a *953 dead weight piston gauge. Accurate pressure readings are obtained by adjusting the dead weight gauge and operating the pump until the weight floats.

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288 F.2d 950, 48 C.C.P.A. 904, Counsel Stack Legal Research, https://law.counselstack.com/opinion/application-of-paul-hollis-taylor-ccpa-1961.