Holtzer-Cabot Electric Co. v. Standard Electric Time Co.

28 F. Supp. 58, 41 U.S.P.Q. (BNA) 767, 1939 U.S. Dist. LEXIS 2497
CourtDistrict Court, D. Massachusetts
DecidedMay 29, 1939
DocketNo. 4571
StatusPublished
Cited by1 cases

This text of 28 F. Supp. 58 (Holtzer-Cabot Electric Co. v. Standard Electric Time Co.) is published on Counsel Stack Legal Research, covering District Court, D. Massachusetts primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Holtzer-Cabot Electric Co. v. Standard Electric Time Co., 28 F. Supp. 58, 41 U.S.P.Q. (BNA) 767, 1939 U.S. Dist. LEXIS 2497 (D. Mass. 1939).

Opinion

FORD, District Judge.

This suit involves infringement of a patent, United States patent No. 1,793,-846, granted to one Vernon Durbin, February 24, 1931, and admittedly owned by the plaintiff. The defendant in its answer asserts non-infringement and invalidity of the patent. Claims 1 and 5 only, of the patent, are in suit.

Statements of facts in this opinion may be taken as special findings, and statements as to the law, as legal conclusions, in compliance with Rule 52 of the new Federal Rules of Civil Procedure, 28 U.S.C.A. following section 723c.

According to the patent, it relates to an improvement in nurse call systems which are described as comprising a push button on the end of a cord which is provided with a plug that is received in a wall socket or receptacle so that the patient by pressing the button may cause the nurse to be called. Ordinarily, the pushing of the button lights a lamp over the patient’s door, activates a buzzer, and causes a signal to be exhibited on an annunciator at the nurse’s station. In some of these systems, which were old at the date of the issuance of the patent in suit, provision had been made for causing a signal to be given when the plug was accidentally disconnected from the wall socket. This was done by a switch mechanism which automatically closed the circuit in the wall socket; in other words, short-circuited the system and operated the call system in the same manner as when done by the push button. The nurse, on an-, swering the signal and finding the plug out of the receptacle, restored it, thus cutting off the signals and leaving the patient’s push button operative for normal signal-ling purposes.

At times, when the room was to be repainted, or the cord sterilized, it became [59]*59necessary intentionally to remove the push button plug altogether, and in order to prevent the socket from setting the alarm signal caused by the short-circuiting device, a dummy plug was inserted in the wall socket, thereby cutting off the alarm signal. In the specification the patent states that the use of the dummy plug is objectionable, because it was unattached and likely to be lost; and it was to the problem of getting rid of the dummy plug in these systems that the patentee addressed himself.

The invention of the patentee may be described as one which provided the wall socket or receptacle with a built-in switch which, when the plug was removed, could be turned to cut off the continuing exhibition of a call from the room or patient’s bed, with means provided of blocking the holes in the receptacle to prevent the reinsertion of the plug into the receptacle with the switch in its open or inoperative position (where it would be after the switch was manually turned to cut off the alarm signal), thereby requiring the switch to be restored to its first position in order to reinsert the plug and restore the system so that the customary patient’s signals could be transmitted and also the warning signal could be given, if the plug subsequently should be accidentally removed. This the plaintiff maintained was an improvement over the prior art in that it got rid of the “objectionable dummy plug.” It is well to say in this connection, for purposes of clarity, that if the plug could be inserted before the switch was turned back, the patient could signal the nurse, but no signal would flash if the plug were accidentally removed, and it was to insure the latter that the plaintiff in his device blocked up the holes of the receptacle when the switch was turned to the open position, thereby compelling the restoration of the switch to its original position in order to reinsert the plug and put the system in normal working order.

The patentee described his device as one that consisted of a wall receptacle of insulating material which carried a number of leaf springs and these leaf springs, when the plug is in position, make contact with the prongs of the plug and complete the circuit from the wiring in the wall to the flexible wiring leading to the push button used by the patient. There is also a short-circuiting disk which is scalloped shape, i. e., has certain high proportions and when the plug is out of the receptacle the springs under tension move inwardly and rest on the high portions of the short-circuiting disk completing the circuit through all the springs thereby giving a warning signal that the plug is out. Attached to the short-circuit disk is a switch body member carrying a switch handle. This is all insulating material and is also scalloped in shape and the two members are held together so that the high and low positions are opposite to each other. When the switch is moved manually from the “on” position to the “off” position, the high portions of the short-circuiting disk are removed from underneath the leaf springs and the leaf springs then rest on the high portions of the insulating cam which removes the short circuit through the various springs. In the latter position the high portions of the insulating cam come into the path of the openings so that the openings are mechanically blocked and it is impossible to put the plug in when the switch is in that position (open or inoperative position). When the switch is restored by a manual turning of the switch to the “on” position as indicated on the receptacle the openings are then clear and the plug may be reinserted and the equipment restored to normal operative condition.

The defendant’s alleged infringing device covered by Patent No. 1,911,513, dated May 30, 1933, consists of a plug portion which has protruding prong-like contacts adapted to engage with the resilient contacts in the receptacle. It has, as with the plaintiff’s device, a switch protruding centrally from the receptacle for the purpose of cutting off the signals while leaving the plug removed. The defendant’s two-position switch is a central spring-pressed insulated plunger or switch that can move inwardly or outwardly along the longitudinal axis of the socket, and has on its outer end a depression with inwardly sloping sides. This plunger has a metal ring at its inner end and is normally pressed outward toward the plug by a coil spring. The cap of the socket has bayonet joints therein with shoulders, and the plunger has pins designed to engage therein, which provide means for locking the switch or plunger in its second or open circuit position. When the plug is inserted, it presses the switch in against its coil spring, and in that position the metal ring [60]*60on the switch is spaced from spring contacts which extend downward from the socket, and no electrical connection is established between them. If, however, the plug is pulled out, the coil spring forces the switch outwardly bringing the metal ring thereon in contact with the spring contacts, closing the circuit through them and operating the signal. When the plug is intentionally removed by the hospital authorities the socket can be prevented from short-circuiting by pressing in the switch against its spring with the finger, at the same time turning it in a clockwise direction. The pins on the switch then engage the shoulders in the bayonet joints, locking the switch in second or open-circuit position, with the metal ring and contact spring held speced apart. Reinsertion of the plug then causes the switch automatically to turn back to operating position by a cam-like action of the projection of the plug against the sloping surfaces of the depression formed in the outer end of the switch. It may be also restored to normal operative position by a manual turning of the switch.

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28 F. Supp. 58, 41 U.S.P.Q. (BNA) 767, 1939 U.S. Dist. LEXIS 2497, Counsel Stack Legal Research, https://law.counselstack.com/opinion/holtzer-cabot-electric-co-v-standard-electric-time-co-mad-1939.