Appeal from the District Court of the United States for the Eastern District of Wisconsin; Ferdinand A. Geiger, Judge.
Before ALSCHULER, EVANS, and FITZHENRY, Circuit Judges.
FITZHENRY, Circuit Judge.
Appellee brought this suit to restrain further infringement and recover damages for past infringement of its patent No. 1,517,811 to Willis for a switching handle.
At the conclusion of the trial, the patent was held valid and infringed and an accounting ordered.
The court predicated its decree upon formal findings of fact in which it found that appellee was the owner of United States letters patent No. 1,517,811, dated December 2, 1924, for improvements in switching handles (for use on vacuum cleaners and kindred devices); the letters patent having been granted to appellee as the assignee of Olo C. Willis, the inventor. Appellee commenced the manufacture and sale of vacuum cleaners with handles embodying the claims of the patent in suit in 1919. Appellant commenced to manufacture the alleged infringing handle early in 1922, and has used it continuously since that time. Appellee's patent issued December 2, 1924, and on December 22, 1924, appellee brought suit against an infringer, which suit was settled in May, 1928, and a consent decree entered sustaining the patents and finding infringement thereof. Licenses under the Willis patent have since that time been taken by numerous manufacturers of vacuum cleaners so that about 80 per cent. to 90 per cent. of the portable electric cleaners made and sold since the issue of the Willis patent have been made and sold by appellee and its licensees under that patent. The prior art Kirby patent, No. 1,195,363, was assigned to Electric Vacuum Cleaner Company, which took a license under the Willis patent; and the prior art Stecker patent, No. 1,268,173, was assigned to the Eureka Vacuum Cleaner Company, which took a license under the Willis patent, recognizing the merit of Willis over Kirby and Stecker.
The court found that the pistol grip and the trigger switch were old, but the Willis construction embodied greater convenience in having the switch at the bottom of the handle and more readily adapted to operation by one hand and being easily removable without dismantling the handle. It found that appellant's switching handle was substantially of the same construction described in the Willis patent and accomplished the same objects.
While the proof showed the lapse of a considerable length of time during which the appellee might have known of the infringement but did not press it, the court found appellee was not estopped by laches from having the relief prayed for.
In his application for the patent in suit, Willis described his invention and its purpose as follows:
"My invention relates to improvements in switching handles such as are particularly adapted for use with electrically actuated appliances adapted for manual use. More particularly, the handle of my invention is designed and adapted for the actuation and control of suction cleaning apparatus; the needs of which are exacting and peculiar.
"I am aware that in certain prior handle structures provided for a similar purpose, upwardly protruding switch members have been designed, which are adapted and intended to be actuated by a sliding movement of the thumb. This mode of actuation, however, necessitated by the above construction requires the release of the handle by operative's thumb. Moreover, such prior switches are not intended nor adapted for ready removal, inspection and repair. These results, on the contrary, are attained in my improved construction by providing an electric unit which is easily removable from the handle.
"In the manipulation of a portable suction cleaner, it frequently is necessary slightly to tilt, and thereby break the seal of the nozzle, in order to afford a sudden inrush of air and pick up small particles. The rigidly locked pistol grip is admirably adapted for this and other modes of using and manipulating the cleaner.
"Furthermore, the switch trigger, positioned as it is for the convenience and almost instantaneous actuation of the user's first finger, affords the most efficient means known to me for the electrical control of the connected appliance. This may not appear to be of much importance upon first impression, but the fact remains that not infrequently the fan of the suction cleaner should be instantly stopped, as when a portion of a curtain or hanging is drawn accidentally into the nozzle. With the ordinary type of switch control, two or more fingers, or the disengaged hand of the operative, are required to turn the switch on or off, with some attendant delay. This obviously is not the case with my improved construction, for the reason that the finger is invariably in position, with the user's hand upon the pistol grip, either to turn the switch off or on at a moment's notice. This is accomplished without removing the hand from the pistol grip or losing manual control of the attached suction sweeper.
"Another important advantage attained by positioning the trigger switch substantially at the inner angle of the handle is its protection from damage, not only to the trigger, but the switch parts themselves, in the event that the handle falls or is struck violently to the floor. Moreover, the trigger will not catch, either to operate the switch inadvertently or break the switch parts, when the suction cleaner is used beneath articles of furniture, such as pianos, tables, couches and the like. It will also be observed that the spring-protected conducting cord f is brought of the mounting plate at a ...