Application of Davis

203 F.2d 721, 40 C.C.P.A. 895
CourtCourt of Customs and Patent Appeals
DecidedApril 15, 1953
DocketPatent Appeal 5955
StatusPublished

This text of 203 F.2d 721 (Application of Davis) 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 Davis, 203 F.2d 721, 40 C.C.P.A. 895 (ccpa 1953).

Opinion

GARRETT, Chief Judge.

This is an appeal from the decision of the Board of Appeals of the United States Patent Office (hereinafter referred to as the board) affirming the rejection by the Primary Examiner (hereinafter referred to as the examiner) of all the claims numbered 1 to 8, inclusive, of appellants! application for patent entitled “Means For Preventing Collapse Of Molded Concrete Products When The Core Is Withdrawn.”

Claims 1, 2 and 7 are directed to method and the others to the apparatus referred to in claims 3, 4, 5 and 6, as a mold box and in claim 8 as a concrete block molding machine.

Claims 2, 3 and 6 which the board selected as representative, when taken together, cover all the material features of appellants’ claimed invention. They read:

“2. The method of preventing the collapse of a hollow block in- molding hollow concrete blocks or similar products when the core is rapidly withdrawn and the outer mold stripped simultaneously from the block, which comprises using a hollow core with a vent opening in the top and supplying a metered charge of compressed air at a determined pressure to the hollow interior of the core through the vent opening, said charge of air under pressure calculated so as to substantially equalize the pressure on the outside and inside of the block by correlating the air charge with the speed of withdrawal of the core from the block.
“3. A mold box containing one or more cores and means for preventing the collapse of the hollow molded block when the cores and mold are stripped from the molded block which comprises the said mold box, the said core or cores, and a conduit and passageways through the core or cores for supplying compressed air to the space left by the core or cores in the block as they and the mold are withdrawn.
“6. A mold box containing one or more cores and means for preventing the collapse of the hollow molded block when the cores and mold box are lifted contemporaneously and rapidly leaving the block stripped, which comprises the said mold box, the said core or cores united to the mold box to lift therewith, and a conduit and passageways through the core or cores for supplying compressed air to the space left by the core or cores in the block as they are withdrawn, the air supplied to the space in the block being a charge co-ordinat-ed to the speed of withdrawal of the core from the block so as to keep the pressure on the inside and outside of the block substantially equalized, a cam and cam-controlled valve for opening the supply of air to the space in the block and closing off the supply of air, the amount of opening of the valve being adjustable by means of lost motion between the cam and the valve, and means for actuating the valve adjustable to vary the amount of lost motion and, consequently, the opening of the. valve.”

*723 The following patents were cited as prior art references: Besser 1,706,647 Mar. 26, 1929; Strong 2,193,847 Mar. 19, 1940; Weaver 2,297,090 Sept. 29, 1942.

As we understand appellants’ application, the feature particularly emphasized as constituting their claimed invention is that of equalizing the atmospheric pressure on the outside and inside of the green, freshly molded blocks during the very short period (appellants’ brief says “a little more than a half a second”) in which the mold and the core are being simultaneously pulled off, or stripped from, the molded block by a described lever arrangement. The atmospheric equalization is accomplished by compressed air introduced into the space left by the core while it is being withdrawn from the block, the force of the compressed air being regulated by a cam arrangement and thus coordinated to the speed of withdrawal of the core from the molded block. The withdrawal of the core tends to create a vacuum in the space within the block from which the core is withdrawn and by filling such space with air, the flow of which is properly regulated, the inner walls of the still plastic cement are prevented from crumbling or deformation.

We quote from the brief on behalf of appellants the following descriptive matter:

“The appealed claims are directed to a method and apparatus for providing metered compressed air to the hollow cores of the molds when the mold box and cores are lifted off the molded blocks. The purpose of the compressed air in a metered charge is for equalizing the pressure on the outside and inside of the freshly molded walls so that they will not be collapsed. The mold box usually contains three molds. Suspended from the top of the mold box are a set of cores which form the hollows in the blocks, * * *. The mold box, the molds and the suspended cores open at their lower ends are set upon a plate called a ‘pallet’. Both the molds and the cores are open at their lower ends. The spaces around the cores and in the molds are filled or poured with a concrete mix. The pallet, the mold box, the molds and the cores are then vibrated to pack the material firmly in the molds and around the cores. This material is also, in some machines, tamped by packers that are dropped on the top of the contents of the mold. These are vibrated to do the tamping. After the vibrating and/ or tamping operation, the cores, the mold box and the molds are lifted off the molded blocks which rest on the pallet.”

Claims 1 to 4, inclusive, and 7 and 8 were rejected as unpatentable over the Strong patent, designated by the board as the basic reference, in view of the Besser patent, and claims 5 and 6 on those references with the addition of the Weaver patent relating to the cam and cam-controlled valve features defined in those two claims.

The Weaver patent “relates to cam mechanisms, more particularly it relates to a delayed action cam mechanism for controlling air valves used in connection with intermittent operating machines * *

In a broad sense, both the Besser and Strong patents are in the same field of art as the application of appellants; that is, the manufacture of molded products of concrete or like cementitious materials for use in the construction of buildings. Besser refers most specifically to concrete blocks, “especially those of hollow form”. Strong names “units such as wall slabs, floor slabs, roof slabs, etc., for use primarily in building construction.” We find no statement in the specification indicating that the slabs are hollow.

The Besser patent which, according to the brief for appellants, is a hand operated apparatus, contains 27 claims all being for a mold or mold box having various features including, as stated in many of the claims, a core about which the plastic material that forms the finished block is molded. When the core is withdrawn a hollow block results. The apparatus for the production of such blocks appears to be the distinctive feature constituting Besser’s invention, the patent on which apparently expired several years ago.

*724 The specification recites:

“ * * * [The] invention is especially adapted to molding operations in which it is desired to remove the molds away from the finished blocks,’ and in doing so, remove the cores from the blocks at the same time, and providing means for holding the block down while the mold and cores are removed.

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Bluebook (online)
203 F.2d 721, 40 C.C.P.A. 895, Counsel Stack Legal Research, https://law.counselstack.com/opinion/application-of-davis-ccpa-1953.