81 F. 865 | 3rd Cir. | 1897
' This matter comes before the court on an appeal from a decree of the circuit court for the Western district of Pennsylvania (78 Fed. 626), granting to the complainants a preliminary injunction based upon two patents, No. 455,-993, July 14, 1891, and No. 527,102, October 9, 1894, issued to Josiah Barrett, and assigned to the Duff Manufacturing Company. The claims involved are 1 and 6 of patent No. 455,993, and claim 19 of patent No. 527,102; but, inasmuch, as the defendant, in his answer, consents that decree be made against him as to claim 19, patent No.
Claim 1: “In a jack, tbe combination of a bar having teeth on one side thereof, a privotal lever, two pawls pivoted to said lever, and having fingers rigid therewith, and a yielding tripping plate having lugs thereon adapted to engage with said fingers, and through the same draw the pawls from engagement with the toothed bar, substantially as and for the purpose set forth.”
Claim 6: “In a jack, the combination of a bar having teeth on one side thereof, a pivotal lever, a pawl pivoted to said lever and having' a finger rigid therewith, and a yielding tripping plate mounted on the frame, and having a lug adapted to contact with said finger, and through the same draw the pawl from engagement with the toothed bar, substantially as and for the purposes set forth.”
Tn a former suit brought in this circuit entitled Manufacturing Co. v. Forgie, 57 Fed. 748, upon full consideration the court held this patent, No. 455,993, to be valid, and decided that the complainant was entitled to have'such a broad construction put upon his claims as would enable him to obtain the benefit of the full scope of his invention. The validity of the patent having been so sustained, the only question now before us for consideration is one of infringement, and in determining it the court should be guided by the rules of construction laid down in the case above referred to, and which are in conformity with the decision in Electric Co. v. La Rue, 139 U. S. 601, 11 Sup. Ct. 670. In the opinion which has been filed in this cause, and which forms the basis of the decree appealed from, the learned judge sets forth clearly and fully the state of the art before and at the time application was 'made by Barrett for his patent No. 455,993, and the need which existed for further improvement in the then existing mechanism to adapt the lifting jack of Barrett, manufactured under patent No. 312,316, to the requirements of an “oil-well jack.” This mechanism had been provided with a rigid tripping plate, and, in order to provide for the withdrawals of the pawls, during the reversing operation, there were pivoted to said pawls spring-actuated fingers, which, when the lever was operated, moved in contact with the tripping plate in such a way as to draw the pawls away from the teeth of the rack. In applying this mechanism to the purposes of an “oil-well jack,” it was found that when the joint was tightly coupled together, and the wrenches still applied thereto, the wrenches exerted a very strong pressure against the carriage and the fixed post on the rack bar, and the operation to remove the wrenches from the drill rod so as to permit the latter to be used was found to be very difficult. To overcome this difficulty was the object of the yielding tripping’ plate provided for in the claims of patent No. 455,993, above set forth. By the substitution of the yielding tripping plate having a lug or lugs thereon adapted to engage with said fingers, and through the same draw the pawls from the toothed bar “for the device described in patent No-. 312,316, Barrett gained for his new machine simplicity and strength, — simplicity, in that the parts were reduced in number by the removal of the levers and one of the springs; and strength by his ability to increase the size of the pawls, and relieve them from the strain of carrying the reversing mechanism.” In patent No. 455,993 we find