Patent GB-974296-A (GB)
Title: Apparatus for measuring the lengths of threads or films wound on winding apparatus
IPC: B65H61/00
Filed: 1963-04-02
Abstract: 974,296. Measuring and recording wound lengths of thread. ALGEMENE KUNSTZIJDE UNIE N. V. April 2, 1963 [April 5, 1962], No. 12958/63. Heading D1F. [Also in Division G1] Apparatus for measuring the length of thread or film wound on to a package comprises a rotating disc mounted coaxially with and adjacent the package, a displaceable member which contacts the surface of the package and which is displaced outwardly as the package grows and to which is attached a further member which co-operates with the disc in a manner dependent both on its radial position and on the speed of the disc to activate recording and indicating means the reading of which gives a measure of the length of thread wound on the package. The speed of the disc must be proportional and preferably equal to the package spindle speed and the distance radially of the member from the spindle axis must be proportional and preferably equal to the radius of the point at which thread is being wound on to the package to give an accurate measurement. In the winding of thread on a package 1, a member 10 located at the same mean radial position as a thread guide 7 co-operates with a rotating disc 9 mounted on the spindle 2 to activate electrical impulse recording means 12. Thread guide 7 reciprocates under the action of a push rod and is mounted on a back-plate 3 which is pivoted to move outwardly as the package grows (Fig. 1, not shown). In each revolution of the disc 12 the member 10 passes over a number of electrically conductive strips the number of said strips being directly proportional to the radial distance at which the member 10 is situated. The arrangement is such, therefore, that the recording means 12 record and indicate an integrated or totalised product of revolutions of the disc and radial distances of the member 10 which indication is proportional to the length of thread wound on the package. In another embodiment a wheel attached to the displaceable member is rotated by contact with the surface of the disc, the axis of the wheel being kept perpendicular to the spindle axis, and the recording means record the revolutions of the wheel. In alternative arrangements the disc is arranged to have optical or electrical resistance properties which vary with the radius and the optical or electrical transmission through the disc is converted into an electrical output and fed to a tacho-dynamo coupled to the package spindle. The power output of the dynamo is then summed in a watt-hour meter to give a reading proportional to the length of thread wound on the package. In still another embodiment the disc is magnetisable and magnetic writing and reading heads spaced circumferentially from each other are provided. The time delay between writing and reading a magnetic impression on the disc is a function of the speed of the disc and of the radial position at which the operation takes place. Since excitation of the writing head is made dependent upon the reading of impressions by the reading head the frequency and hence also the total number of signals from the reading head is a function of the speed of the disc and of the radial movement of the magnetic heads and thus also of the length of thread wound.