Hydraulic Press Corp. v. Coe

134 F.2d 49, 77 U.S. App. D.C. 251, 56 U.S.P.Q. (BNA) 437, 1943 U.S. App. LEXIS 3488
CourtDistrict Court, District of Columbia
DecidedFebruary 15, 1943
DocketNo. 8210
StatusPublished
Cited by1 cases

This text of 134 F.2d 49 (Hydraulic Press Corp. v. Coe) is published on Counsel Stack Legal Research, covering District Court, District of Columbia primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Hydraulic Press Corp. v. Coe, 134 F.2d 49, 77 U.S. App. D.C. 251, 56 U.S.P.Q. (BNA) 437, 1943 U.S. App. LEXIS 3488 (D.D.C. 1943).

Opinion

RUTLEDGE, Associate Justice.

Appellants’ suit, to secure a decree authorizing the issuance of a patent, was filed pursuant to Rev.Stat. § 4915 (1878), 35 U.S.C. § 63 (1940). The appeal is from a judgment of dismissal. The claimed invention relates to a hydraulic press for forming sheet metal into various shapes. The principal issue is whether appellants’ claims have been anticipated by the Ferris Patent, No. 1,970,134.

Claims 4, 5 and 7 are the only ones now in issue, the others having been abandoned or cancelled. Claim 4 may be taken as typical, but we set forth the other two in the margin, with variations from the language of Claim 4 indicated in italics.1 Claim 4 is as follows:

[50]*504. A method of generating and utilizing hydraulic power for clamping articles being drawn comprising clamping the article by hydraulic means at its periphery with different pressures at different' locations therearound, applying a drawing force to the article while so clamped, diverting a portion of the drawing force to generate hydraulic pressure during the drawing operation, and applying the pressure so generated to produce the clamping action. '(Italics added.)

Appellants’ present position, is that Ernst’s invention over Ferris consists in the features disclosed in the italicized language. They insist, contrary to appellee’s contention, that Ferris does not disclose them, and apparently concede that the features described in the remaining language are found in Ferris. The basic position of the Patent Office is that the claims are too broad. That is, they are drawn so broadly that they are readable on Ferris and consequently cannot be allowed, whether or not Ernst’s modifications would be inventive and claims allowable if drawn in properly limited terms. However, it is not conceded that invention exists, and the District Court found expressly there is none. The positions of both parties have varied somewhat during the proceedings, including those in the Patent Office,2 and in order to make the respective contentions clear we turn to a more specific statement of the facts.

The chief claimed advantages of appellants’ invention are increased efficiency and economy of operation. Higher operating speed is achieved, it is said, at the same time with greater conservation of energy. It is not disputed that Ernst has made a useful improvement upon the prior art or that it has been commercially successful. Appellants’ machine, as disclosed in the drawings, is much simpler than that of Ferris with, it may be assumed, the resulting economies simplicity usually brings.

The general characteristics of the two disclosures are set forth in the trial court’s findings of fact as follows:

“The Ernst application here involved discloses an hydraulic press for forming sheet metal in which the metal to be shaped is clamped at its periphery while the central portion is forced into a die cavity by means of a plunger. The plunger is actuated by an hydraulically operated piston and the clamping pressure is applied by means of auxiliary pistons which move in cylinders formed in a block at one end of the main piston. The arrangement is such that as the main piston moves the drawing plunger toward the work it also serves to> generate hydraulic pressure in the cylinders containing the clamping pistons.
“The Ferris patent No. 1,970,134 discloses a press in which a sheet of metal is clamped at its margin while the central portion is forced into a cavity by means of an hydraulically actuated plunger. The liquid for actuating the plunger is supplied by a pump which, the patent states, is driven at a constant speed. The same pump also supplies liquid to the hydraulically actuated mechanism which clamps the periphery of the sheet during the drawing operation. The clamping means may be adjusted to provide different pressures at different portions of the periphery. The means for effecting this adjustment comprises adjustable relief valves for releasing pressure fluid at different points on the periphery when predetermined pressures are attained.”

The processes are identical in using hydraulic force, derived from a pump, for both clamping and drawing or plunging operations. The former holds the work piece in place, while the latter molds it to the desired shape. Both clamp the work [51]*51piece at its periphery to a die, with different pressures at different locations around the periphery. In both this differential in clamping pressure is maintained by relief valves which allow the liquid to escape when the pressures reach desired points. This feature permits adjustment of the clamping pressure to work pieces of irregular thickness and shape. Both use h ,-ckau!ic:úly operated pistons or mechanism-. for applying the clamping pressure. Both processes apply the drawing force to the central part of the work piece while it is lick; in place by the clamping force. Both -use a piston to apply tlie drawing force, hydraulically operated. In both the drawhig force, derived through the piston, forces the central portion of the work piece into a cavity in the die, thus molding the metal into the desired shape. These are the principal and basic features of identity-, though it should be mentioned that in both instances the only force which is introduced into the machine, whether for the clamping or for the plunging operation, comes from a single source, namely, the pump which Ferris specifies shall be operated at constant speed.

We turn now to the features of difference. The two processes operate in opposite directions. In Ferris the die is at the top and the plunging piston at the bottom of the machine. Both the clamping and the plunging or drawing operations are applied in an upward direction against the work piece and the die. In Ernst the die is at the bottom and the plunging piston operates downwardly against the work piece and the die to which it is clamped. This difference in itself is immaterial. But the basic difference, and the one in which invention is claimed, lies in the operation of the clamping force. This will be described in detail. To do this, however, further attention must be given to the operation of the drawing force, with which the clamping force is associated in both machines, but in a somewhat different manner.

As has been stated, the whole force introduced into the machine in both cases, that is, the only external force, is derived from a pump, which in fact supplies the pressure for both the clamping and the plunging or drawing operations. Because it will be convenient to distinguish it from other forces, we shall call this total force introduced into the machine from the pump the external force.

In Ferris this force leaves the pump at one point and travels a very short distance, probably not more than a few inches, in a single pipe. The pipe then branches into two separate pipelines, one of which carries liquid to the clamping mechanism, the other conducting it to the plunging piston. One line therefore carries what may he called the clamping force, the other the drawing force. It is obvious that the clamping force is diverted from the supply line which extends from the pump to the drawing ram or piston. Operation of the clamping mechanism necessarily requires a continuous flow of liquid from the pump as* long as the clamps are in action. In other words, the clamping pistons operate by direct and continuous application of force from the pump.

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Bluebook (online)
134 F.2d 49, 77 U.S. App. D.C. 251, 56 U.S.P.Q. (BNA) 437, 1943 U.S. App. LEXIS 3488, Counsel Stack Legal Research, https://law.counselstack.com/opinion/hydraulic-press-corp-v-coe-dcd-1943.