dissenting-in-part.
I respectfully dissent from the majority affirmance of the finding of infringement because the district court failed to make adequate findings of fact and failed to provide its interpretation of the claim in light of the prosecution history. In other respects, I join the majority.
Claim 1 of the ’592 patent reads as follows:
1. A device for introducing a controlled amount of cooling water into a conduit for superheated steam, comprising a cylinder having a conical nozzle at one end, a plurality of velocity nozzles provided through the cylinder wall to connect the interior of the cylinder to a source of high pressure water located outside of said cylinder, said velocity nozzles being spaced axially and directed substantially tangentially to the cylindrical inner surface of said cylinder, a piston movable in said cylinder to progressively expose said velocity nozzles when moved backwards from a position closing said conical nozzle, said piston having a piston rod connected thereto extending through the rear end of said cylinder connected to an actuating member, the swirling water from said tangential ve*279locity nozzles passing directly through said cylinder and conical nozzle into said steam. [Emphasis added.]
The specification notes that “[a] plurality of passages through the cylinder wall are spaced axially and directed substantially tangentially. At the outside of the cylinder wall these passages communicate with a high pressure desuperheating water source.”
The specification further notes that “[a] plurality of passages 15 through the cylinder wall 4, which are in the form of velocity nozzles are spaced axially as well as radially, preferably uniformly disposed along an imaginary helical line.”
The trial court ruled from the bench as follows:
I find each and every element of claim one is present in the Gustafsson disclosure in patent ’592 and in the DA-4 [sic] and in the DA-8. If there was no literal infringement, I find that the devices of the DA-4 [sic] and the DA-8 fall within the doctrine of equivalents for the reason that they perform substantially the same function in substantially the same way to achieve substantially the same result.
The trial court’s written findings state as follows:
11. The DA-6 desuperheater manufactured, offered for sale and sold by defendant Eur-Control USA, comprises a central hollow cylinder forming a swirl chamber having a conical nozzle at the discharge end, from which a conical spray of water is ejected into a steam line. A plurality of ports is provided in the wall of the cylinder which connect the interior of the cylinder with a source of high pressure water externally of the cylinder. The ports are spaced axially of the cylinder and direct water into the cylinder tangential to the inner surface of the cylinder, causing the water to follow a swirling path toward the conical discharge nozzle. A movable piston within the cylinder progressively exposes the ports as it is moved from a closed position to control the rate of flow of water through the desuperheater.
12. The DA-8 desuperheater differs from the DA-6 desuperheater in that the ports through the cylinder wall are directed at an angle inclined toward the discharge nozzle and are moved slightly inward from the position of the ports in the DA-6 so they are not exactly tangent to the inner surface of the cylinder. The ports, however, are directed substantially tangential to the inner surface of the cylinder.
13. The DA-6 and DA-8 desuperheat-ers manufactured and sold by Eur-Control USA consists of a combination of elements which, as to their size, function, general shape, manner of cooperation and purpose, correspond to the parts of the desuperheater described in the ’592 patent and called for by Claims 1 and 2 thereof, and the combination of such parts performs the same function in substantially the same manner to accomplish the same result as the combination of elements of the desuperheater shown and described in the ‘592 patent and called for by Claims 1 and 2 thereof.
14. Claims 1 and 2 of the ’592 patent include within their scope desuperheaters of the DA-6 and DA-8 type manufactured and sold by Eur-Control USA. [Citations to the record omitted, emphasis added.]
The trial court’s conclusion of law regarding infringement is as follows:
■ 2. Eur-Control USA has infringed Claims 1 and 2 of United States Letters Patent 3,524,592 by the manufacture and sale of its DA-6 and DA-8 desuperheaters.
Upon Kalle’s motion to reconsider the findings, the trial court’s order stated as follows:
Despite defendants’ arguments, the Court finds that the evidence adduced at trial does support its finding that Claims 1 and 2 of the ’592 patent include within their scope desuperheaters of the DA-6 and DA-8 type manufactured and sold by Eur-Control USA. The Court recognizes the differences in structure and *280performance between the ’592 patent and the DA-6 and DA-8 devices but remains convinced that the DA-6 and DA-8 desu-perheaters perform the same function in substantially the same manner as the desuperheater specified in the ’592 patent.
The above statements constitute the entirety of the trial court’s statements on infringement.
The trial court’s succession of statements concerning infringement obfuscates the nature of its holding. It is unclear whether, after reconsideration, the trial court still finds literal infringement. Moreover, the court’s various misstatements of the doctrine of equivalents test cast doubt upon the majority’s conclusion that “[t]he district court was well aware of the basic rules concerning the doctrine of equivalents.” Most importantly, however, the decisions below do not contain sufficient findings upon which to review the holding of infringement. Rather, we have only the conclusory statements set out above. In view of the prosecution history showing amendment from “ports” to “velocity nozzles” before the examiner would allow the claims, it cannot be assumed that Eur-Control’s “ports” are the same or equivalents of “velocity nozzles.” Indeed, at least pri-ma facie “ports” are significantly different from “velocity nozzles.”
The majority opinion interjects some evidence of its own by way of its garden hose example and then speculates about what the trial court inferred. However, the trial court itself expressed no finding concerning the relationship between the DA-6 and 8 ports and the velocity nozzles claimed. Indeed, Eur-Control asserts that no evidence was offered to establish equivalency, while Yarway points to certain testimony of its witnesses. However, following a bench trial, we are to review findings, not scrutinize the record for evidence to support inferred findings.
Because I believe the findings are deficient, I would remand for adequate findings on the infringement issue.