Technitrol, Inc. v. Control Data Corporation

550 F.2d 992, 193 U.S.P.Q. (BNA) 257, 1977 U.S. App. LEXIS 14394
CourtCourt of Appeals for the Fourth Circuit
DecidedMarch 8, 1977
Docket75-1857
StatusPublished
Cited by15 cases

This text of 550 F.2d 992 (Technitrol, Inc. v. Control Data Corporation) is published on Counsel Stack Legal Research, covering Court of Appeals for the Fourth Circuit primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Technitrol, Inc. v. Control Data Corporation, 550 F.2d 992, 193 U.S.P.Q. (BNA) 257, 1977 U.S. App. LEXIS 14394 (4th Cir. 1977).

Opinion

WIDENER, Circuit Judge:

This patent case concerns an automatic reset feature, a device to prevent information loss in a magnetic data storage system. Technitrol, Inc., the patent owner, brought an infringement suit for an injunction and damages against Control Data Corp., a manufacturer, seller, and user of such systems. Control Data filed a counterclaim asking the court to declare Technitrol’s patent invalid and moved for summary judgment for failing to comply with 35 U.S.C. § 112, para. 2, which reads in pertinent part:

“The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention. ...”

Looking to an affidavit by an expert filed by Control Data, the record of an allied case in the Court of Claims, and the language of the patent itself, the district court held claims 1-15 and 17-24 invalid as not “particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention,” 394 F.Supp. at 520, relying on paragraph 2 of § 112 and rejecting the defendant’s position that the claims are adequate under paragraph 3 of § 112. Sua sponte, the court also granted summary judgment for the defendant on the remaining claim 16 based largely on its holding as to the other claims. Technitrol now appeals.

We are of opinion that the claims adequately describe the invention as we consider them here. We therefore vacate the district court’s grant of summary judgment and remand for further proceedings.

I

Technitrol’s patent was originally issued to T. K. Sharpless and E. S. Eichert in 1952 as No. 2,611,813. By assignment, Techni-trol is, and at all pertinent times has been, the owner of the patent.

The patent describes a computer system used, for example, in making airline reservations, composed of a central storage unit where information about various flights is stored, and a number of remote stations, such as airport reservation desks, which communicate electrically with the central unit. An operator, by punching certain keys on the keyboard at the remote station, can ask the central storage unit whether seats are available on a particular flight. If seats are available, the invention can make reservations on flights, or it can cancel them, or it will indicate if a flight is full.

The remote stations communicate with the central storage unit through electrical transmission lines. Each remote station has keyboards by which an operator can designate a particular flight about which he desires information and the number of seat reservations needed.

The keys, through appropriate circuitry, indicate to the central station the register which contains information about the desired flight. After setting the keyboard, the operator presses a start switch which operates a selector circuit to insure that only one keyboard at a time can communicate with the central station. This avoids the possibility of simultaneous duplicate requests to a register from more than one remote station.

To make reservations, the operator communicates the number and flight to the central storage unit. There, the total number of seats and confirmed reservations of each particular flight is stored on a corresponding register. When the operator selects the appropriate flight number, the machine selects the corresponding register and adds the number of reservations desired to the previous total. If the sum of these is less than the total of reservations available, the reservation request is confirmed, the number of reservations requested is added to the previous total, and the new total is recorded in the storage register where it is available for similar access in the future. *995 But if the sum exceeds the total of reservations available, the application is rejected, the inquirer is so notified, and the old number remains unchanged.

The central storage unit is a magnetic memory device consisting of several continuously revolving magnetic disks (information disks 2, 3, 4, 5) 1 mounted on a common rotating shaft. An electric motor drives the shaft. Information is stored on the disks in magnetic pulses, which, when arranged in groups around the disk, are called registers, one group being one register. Each register contains information about a particular airline flight such as the number of seats already reserved and the number still available.

Magnetic recording heads (C, D, E, F) are mounted adjacent to the disks. These either read what is on the disk, add to it, or erase from it. Thus, as the disks rotate on the shaft, the recording heads, through appropriate circuitry, can read or erase the magnetic pulses already recorded, or can place new pulses on the disks.

Also located on the common shaft with ¡ the information disks is a master clock disk ' (1). Around the clock disk, two channels of magnetic pulses are recorded. One channel has 160 evenly-spaced pulses; the other, one pulse. Magnetic pickup heads (A, B) are located over each channel. The 160-pulse head is connected to a scale-of-ten counter (b) which divides the information from the disk into sixteen 10-pulse registers. Pulses from the scale-of-ten counter, when applied to a binary counter device (c), produce 16 unique voltage combinations, each one of which corresponds to one of the registers on the information disk. The unique voltage combinations (originating at the various registers) are successively fed into a coincidence circuit (d).

When the remote station operator pushes the key to select a particular register, the key generates a voltage combination corresponding to one of the unique voltage combinations originating on the rotating disk which is also fed into the coincidence circuit (Vi, V2, V8, V4). When the disk rotates to the particular register so that its voltage combination matches the one generated by the operator, the coincidence circuit detects the coincidence and produces an output activating the magnetic recording heads (C, D, E, F) which read, write, or erase.

There is general agreement here (not later binding) that a previous magnetic storage system or systems accurately located the registers as long as operation continued without interruption. When interrupted, however, as by a power failure or merely cutting the control station off, position volatility occurred and the information was lost. In essence, this means that the clock disk and the counters, normally in synchronization, lose synchronization when power is cut off. This happens because the counters, electronic devices, stop operating when power stops; and because of rotational inertia, the disks, being mechanical devices, may rotate slightly after the power is cut off, and thus may move out of synchronization with the counter. On restart, the counters, which have lost count of the physical location of the registers, do not pick up the count where they left off with the corresponding register. On start-up, therefore, it is essential that the counters be reset to synchronize them with the registers.

The Sharpless-Eichert invention does this by the one-pulse-per-revolution channel on the clock disk.

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550 F.2d 992, 193 U.S.P.Q. (BNA) 257, 1977 U.S. App. LEXIS 14394, Counsel Stack Legal Research, https://law.counselstack.com/opinion/technitrol-inc-v-control-data-corporation-ca4-1977.