ALMOND, Judge.
This is an appeal from the decision of the Board of Appeals affirming the rejection on prior art of claims 10-13, 15 and 16 in appellant's application
In essence, the claimed invention consists of mounting an optical pyrometer on the upper end of an oxygen lance used in the LD (Linzer Dusenstahl) basic oxygen steel refining process. It is the function of the lance to supply the necessary oxidant to the melt and also to serve as a convenient sighting bore for the pyrometer. The combination of a conventional oxygen lance with an optical pyrometer assertedly provides a method and means for measuring the temperature of molten metal during the refining process.
The configurations of appellant's drawings are set forth below:
Claim 10, the most specific of the appealed claims, reads as follows:
Dependent claim 11 calls for a housing enclosing the pyrometer within the oxygen stream as shown in figure 3. Dependent claim 12 provides for a housing
The references are:
Collins et al. 2,020,019 November 5, 1935 (Collins) Dike 2,232,594 February 18, 1941 Percy 2,305,442 December 15, 1942 Michaux 2,815,276 December 3, 1957 Bieniosek et al. 2,828,956 April 1, 1958 (Bieniosek) Percy 3,080,755 March 12, 1963
The two Percy references will be hereinafter referred to as Percy (442) and (755), respectively.
Collins discloses a device for measuring temperatures of the melt in an open hearth furnace. A pyrometer is mounted for sighting down a tube with an insulated fore end immersed in a metal bath. Air under pressure is supplied to the tube through a conduit. Collins states that air is discharged from the end "immersed in the molten bath and therefore maintains the exposed metal surface at the end of the tube clean by blowing away the slag and metal which would otherwise enter said end."
It should be noted here that appellant discloses that his method of measuring temperatures may be utilized in open hearth furnaces as well as top blow converters.
Dike refers to Collins and discloses a more refined variation of the Collins arrangement. The patent is directed to a molten metal temperature measuring device, comprising a radiation pyrometer located at and aligned with one end of a tubular sighting member. Gases are introduced through an opening and flow down the sighting member to avoid the presence of smoke and fumes in said member. The circulating gas also cools the temperature measuring structure and keeps the lens surface clear of deposits. Dike's cooling arrangement comprises a water jacket and his pyrometer may be cooled by air or water.
Percy (442) relates to a method and apparatus for simultaneously refining molten metal and measuring the temperature thereof. A stream of oxidizing air is directed through the metal bath by means of a wind chest and air holes, thereby creating a reaction zone. An optical pyrometer is shown arranged in axial alignment with one of the air stream holes. An electrical signal is provided, which is fed to means for observing the intensity of the signal. The air stream keeps the pyrometer sight holes free of fumes and debris. The pyrometer may be cooled either by air or water.
Michaux referred to a prior proposal "to set up optical pyrometers or photometers to sight the metal bath in the bottom of the converter through one or a plurality of blast nozzles." He noted that such a process required special precautions. Michaux points out, however, that in such an arrangement "the optical pyrometer of necessity sights one part of the metal at full chemical activity,"
Bieniosek discloses a lance structure comprising a plurality of tubular members arranged in concentric relationship. A central member provides a passageway for an oxygen stream, and a second pipe in combination with a third pipe provides a cooling fluid passageway with inlet and outlet means. A nozzle is in axial alignment and communication with the lower end portion of the central member. The nozzle is shaped to provide a predetermined angle of divergence of discharge. The lance, in operation, is spaced above the melt and is used to direct a stream of refining oxygen upon the surface, thereby creating a reaction zone.
Percy (755) shows his optical pyrometer secured and spaced apart from the housing structure allowing the passage of gas around the pyrometer. The immersed lower end of the temperature measuring apparatus is "removed from the cavity [made by the oxygen blast from a central lance] so that the oxidation taking place in this region will not give erroneous temperature readings."
The examiner considered claims 10, 15 and 16 unpatentable over Bieniosek in view of any one of Michaux, Collins or Dike. He noted that the portion of claim 10 which defines an oxygen lance was not only clearly shown by Bieniosek, but also admittedly old and known in the art. Dealing with that phase of claim 10 relating to the optical pyrometer with its line of sight in axial alignment with the central member, the examiner correctly pointed out that each of Michaux, Dike and Collins teaches the combination of an optical pyrometer which is aligned with and sights down a tubular portion containing a stream of oxidizing gas, and further that Michaux shows an optical pyrometer aligned with a tube and nozzle for continuously measuring temperature, wherein oxygen may be introduced down the sight tube. He further pointed out that in Dike and Collins the pyrometer is mounted at the upper end of, and in axial alignment with, the tubular portion.
With reference to the rejection above noted, the examiner, correctly we think, succinctly stated:
The examiner applied the same basic rationale in rejecting claims 11 and 12, adding Percy (755), however, for its showing of circulating gas around the pyrometer for cooling thereof. With reference to the jacket for the circulation of a cooling fluid recited in claim 12, the examiner applied Dike for his teaching that his pyrometer housing structure may include a water jacket.
Claim 13 was held unpatentable over either Percy (442) or Michaux, either reference further taken in view of Bieniosek. Most of the limitations in claim
In affirming the examiner, the board adopted his position with "additional comments."
In its consideration of claim 10, which embraces the details of appellant's oxygen lance, the board observed that "[s]uch an oxygen lance is old" as shown by Bieniosek and pointed to appellant's specification which states that "except for the upper portion thereof, the structure indicated follows the usual conventional design." With reference to that phase of claim 10 which departs from the conventional design in that it provides the top of the lance with adapter flange means by which an optical pyrometer sensing head can be mounted on the lance, the board reasoned:
In its consideration of claim 11, which depends from claim 10 and sets forth, in substance, that the housing enclosing the temperature measuring device is spaced apart from that device to form a cooling chamber for passage of oxygen around the device, which cooling chamber communicates with the central chamber at the upper end thereof, the board noted that in Percy (755) the temperature measuring device is spaced from the wall which forms a cylindrical chamber around the device, and that gas admitted, by means therefor at the top of the chamber, would cool the device as it passed around same, and concluded that to connect the chamber formed by said wall to the upper portion of the tube forming the oxygen lance would be obvious to one skilled in the art.
In its consideration of claims 12 and 13, the board supplemented the views of the examiner, but in no way deprecated the treatment accorded these claims by him.
We have noted and considered appellant's reliance on Ex parte Kelley, 53 USPQ 682 (Bd.Apls.1941), to the effect that a reference showing the novel combination is required, rather than reliance by the examiner on selected "elements from various references which do not in their old environment have the same cooperative action."
We have here, however, the application of a plethora of references comprehensively and meticulously appraised by the examiner and the board, every one of which belongs, as stated by the examiner, "to a closely related field of activity" whose "structures are so similar that their combination is a natural and logical expediency." The examiner found, with affirmance by the board, and we agree, that the prior art, "the patents to Percy, Michaux, Dike and Collins et al. teaches the combination of an optical pyrometer and a tube or lance-like structure for supplying oxygen or at least an oxidizing gas to a molten metal surface."
Pointedly apposite here is the view expressed by this court in In re
While the record is convincing that accurate measuring of temperature of molten metal during the basic oxygen refining process poses a problem defying adequate solution, it is equally convincing in its total paucity of evidence that appellant's arrangement constitutes any solution thereto. There is no evidence of record to support the statement in appellant's brief that his "device is the only means presently available capable of performing such a task." As pointed out by the solicitor, both Michaux and Percy (755) indicate that appellant's arrangement should be incapable of accurately measuring desired representative temperatures.
We have set out at some length and weighed the analysis and evaluation of the cited references and the application of their teachings to the appealed claims by the examiner and the board, including in our consideration the affidavit of Clarke, which evaluates the teachings of Percy (755), but we are not persuaded that the board committed reversible error in holding the appealed claims unpatentable over the prior art within the purview of 35 U.S.C. § 103. The decision of the board is accordingly affirmed.
Affirmed.
SMITH, J., concurs in the result.
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