L. BARNETT'S APPLICATION FOR A PATENT 698092

148. No.6] REPORTSI OF PATENT, DESIGN, AND TRADE'MARK CASES [1957.] L. Barnett's Application for a Patent 698092. Before THE SUPERINTENDING EXAMINER. 9th May, 1956. L. BARNETT'S ApPLICATION FOR A PATENT 698092. Patent-Application for pateni relating to control devices for air preheaters on furnaces-Opposition on ground (inter alia) of prior; user-Limiting feature of Claim 1 not shown in drawings and not specifically foreshadowed in provisional specification-s-Proposed amendment of Claim 1 by way of deletion of "limiting feature rejected-Prior use of invention before date ot filing the complete specification admitted-Grant refused. S Held (1) that Claim 1 w,as ambiguous but that proposed amendment was not 10 allowable; (2) that the priority date of the claims was the date of filing the complete specification; (3) that the claims were invalid by reason of the admission of prior user before the priority date of the claims. 15 In the decisions reference was made to Westinghouse Electric & Manujacturing Coy.'s Patent (1939) 56 R.P.,C. 76; Rayleigh Cycle i(7oy. v. Miller & Coy. (1948) 65 R.P.C. 141; Hall v. Coombes (1925) 42 R.P.tC. 328; May & Baker Ld. v. Boots Pure Drug Coy. (1950) 67 R.P.IC. 23; and Johnson's Patent (1938) 55 R.P.C.4. 20 The Prematic Industries Ld. opposed the grant of a patent on Application 698092 to Leonard Barnett. A hearing took place before the Superintending Examiner (U'. E. Watts) acting for the Comptroller..General on 9th May, 1956. At the hearing A. D. Russell-Clarke appeared as Counsel for the Applicant and R. Lochner as 'Counsel for the Opponents, In his interim decision the Super- 2S intending Examiner raised a matter regarding the omnibus claim, a matter which bad not been argued at the hearing. 'With the consent of the parties this matter was dealt with in the final decision without further hearing. The interim decision of the Superintending Examiner was as follows:- This is a case in which, although at the hearing the main issues were referred 30 to by Counsel and witnesses were examined and cross examined, a matter of 149 [1957.] REPORTS OF PATENT, DESIGN, AND TRADE MARK CASES INo.6 L. Barnett's Application for a Patent 698092., importance emerged regarding the allowability of an amendment of Claim 1 proposed by Mr. Russell-Clarke and the effect of such an amendment on the priority date which should be accorded to the, claims of the Applicant's specification. It was considered that this matter was of primary significance to the question 5 whether a patent could be granted, since it appeared that if it is found that the proposed amendment is not allowable, and that the claims as they stand at present are entitled only to the date of filing of the complete specification, then by reason of an admission by the Applicant in his supporting evidence that his invention was used prior to that date, the allegation of prior user would be 10 established. At the hearing it was therefore agreed that I should deal with this matter as a preliminary point and issue a decision as to whether the proposed amendment is allowable or not, and in the light of that decision also determine the question regarding the priority date of the claims. The hearing on the 15 main issues raised in that notice of opposition was therefore adjourned pending this decision. The specification relates to improvements in or relating to control devices for air preheaters on furnaces. More specifically stated, the invention relates to control devices in the nature of valves for regulating the supply of air to preheaters used ion boiler or 'other furnaces, and particularly to, valves for 20 controlling the supply of air to preheaters mounted on the outside or inside of the front wall or fire door of a furnace. According to the specification the object of the invention is to provide an improved construction of such control valve which will leave the air delivery aperture completely unobstructed when fully opened, and which is convenient to operate and readily indicates the position 25 of the valve. The claims read as follows :(1) A control device for regulating the supply of air to preheaters for use on boiler and other furnaces comprising a hollow body with air intake apertures and an air delivery aperture which is adapted to be connected to the air passage 30 leading into the preheater and which is substantially equal to the full cross-section of said air passage and a plate or disc valve pivoted externally of said delivery aperture and adapted to be moved laterally across the face of said delivery aperture and capable of completely covering or completely exposing said aperture. (2) A control device according to claim 1 wherein the valve operating spindle 35 projects beyond the body and carries a spring pressed slide block which presses upon and slides over a curved face on the body to hold the valve in any position. (3) A control device according to claim 2 including a handle mounted on said operating spindle and arranged to vary the spring pressure. (4) A control device according to claim 3 wherein said handle is capable of 40 clamping said slide block against the body to lock the valve. (5) A control device according to' any of the preceding claims, having the body formed by a back plate with projecting flanges to which a front plate is attached leaving an air inlet gap and a segmental opening for the valve spindle, said rear plate having an air delivery aperture across which can move a plate or disc 45 valve member pivoted on a stud held in place by the front plate said spindle carrying a spring-pressed slide block and screw-threaded handle arranged to hold the valve in desired position. (6) .A control device for regulating the, supply of air to preheaters for use on boiler and other furnaces, constructed and arranged substantially as described 50 herein with reference to and as illustrated by the accompanying drawings. 150 No.6] REPORTS) OF PATENT, DESIGN, AND TRAD:B MARK CASES [1957.] L. Barnett's Application for a Patent 698092. At the hearing, Mr. Russell-Clarke acknowledged that the question arises as to whether the feature present in Claim 1 whereby the air delivery aperture is substantially equal to the full cross-section 'of the: air passage leading Ito the preheater is referred to in the provisional specification. Moreover he admitted that the inclusion of such a feature in the claim leads to uncertainty regarding 5 the scope of the claim, since it raises the question as to how the size of the air passage leading to the preheater is to be determined. He therefore indicated that to overcome these difficulties he would be willing to delete the feature from the claim. He argued that such a deletion could be regarded as a disclaimer within the meaning of Sec. 31 (1) since any cutting down of the scope of the 10 claim is a " disclaimer" and the claim after such deletion would not introduce or claim anything not in substance disclosed in the specif (...truncated)