US 1676797 A
Description (OCR text may contain errors)
July 10, 1.928.
A. NYMAN TENSION REGULATOR Filed Dec. 18, 1925 INVENTOR fliamnder A/ynuzn BY 5 W A iTORNEY Patented July 10, 1928.
UNITED STATES ALEXANDER NYMAN, OF T UCKAHOE, NEW YORK, ASSIGNOR TO DU IBILIER CONDENSER PATENT oFFICE.
CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.
' TENSION REGULATOR. 7
Application filed December 18, 1925. Serial No. 76,266.
- substantially constant, while the unwinding is in progress.
Other objects and advantages of the invention are set forth in the following description taken with the accompanying drawings; and the novel features of the invention are "pointed out in the appended claims. But this specification discloses only-one embodiment of myinvention and I reserve the right to make changes in the structure actually shown without departing from the principle b which-the invention is governed.
On t e drawings,
Figure 1, is a side view of a tensioning device according to my invention; and Figure 2, is a front view of the same.
The same numerals identify the same parts throughout.
The structure in whichthe invention is embodied, comprises a standard 1, rising from a base or foot 2, and adjacent this standard is mounted a reel 3 upon a shaft or spindle 4 supported in any suitable manner. This reel comprises a central hub 5 attached to a disc .6 and on the hub is fixed a roll of paper or other flexible material indicated by the numeral 7. The shaft 4 may be either fixed or rotatable, so long as the reel can-turn freely thereon, and when the paper 7 is pulled, the reel, of course, will rotate and permit the paper or other strip to be unwound.
In the top of the upright or standard 2 is mounted a fixed journal 8 which supports a movable arm 9 having a hollow boss or hearing 10, which is slipped upon the spindle or journal 8. the latter passing through this boss which acts as a bearing for the swinging arm 9. The lower end of this arm is in the form ,of a yoke 11 between the arms of which'is mounted a roller 12, turning upon a pin or journal 13, supported in the ends of the yoke 11. This roller 13 is intended to rest'upon the roll of Encircling the bearing 10 is a coil spring 14 made fast to this hearing or to the arm 9 at one end and being aflixed at its opposite end 13 to some stationary point such as the spindle or journal 8, or the upright 1. This spring 14 is so stressed that it normally acts to press the roller 12 against the paper on the reel; and as the paper or the like is unwound so that thereel carries less and less of it, the spring 14 acts to keep the roller 12 in contact, with the strip on the reel and move the roller, gradually towards the shaft 4.
Integral with the bearing'IO and therefore r1g1d with the arm 9 is an arm 16 which carries at its lower end, a head or button 17. This head or button normally makes con tact with the disc 6 of the reel and as the strip on the reel unwinds, and the distance from the axis of the shaft 4 to the outer surface of the rolledstrip on the reel decreases, the spring 14 will cause both the arm 9 and the arm 16 to move in unison keeping the roller 12 pressed against the strip on the reel and at the same time, moving the lower end of the arm 16'closer towards the center or axis of rotation of the shaft 4.
In practice, the roll of paper or other material on they reel 3 is mounted upon the shaft 4 in some manner that will enable the reel to turn either on the shaft or with it; while at the same time, axial movement of the reel along the shaft or with the shaft 4 is prevented. The base 2 and upright 1 are then moved into position so that the roller 13 can rest upon the strip on the reel and the lower end of the arm 16 hearing the head or button 17 can make contact with the outer face of the disc 6. As the two arms 9 and 16 are-substantially parallel. their outer or free ends will always be at substantially the same distance from the axis of the shaft 4. Then, as the reel is unwound by tension on the strip of material which it carries, the rotation ofthe reel will be checked to some extent by the frictionbetween the reel and the arm 16. with its button 17.
If, for example, the reel be filled to half the extent shown in- Figures 1 and 2, and a given force be exerted on the strlp 7 to unwind the strip from the reel, the moment of this force will be equal to the pull in pounds multiplied by the distance of the outer layer from the axis of the shaft 4. But with the reel filled to a greater extent as indicated in the drawings, the moment of such a force if the pull on the strip 7 is constant, will be much greater because the lever arm or distance of the outer layer from the axis of the shaft 4 is greater. Therefore, a pull on the strip 7 great enough to unwind it, when all but a few layers have been removed from the hub 5, will be too great when the reel is full, and some regulation is necessary. Such regulation is provided by the friction member 16, the position of which is governed by the arm or element 9. The friction between the disc or flange 6 and the head or button 17 of the arm 16, will be constant, that is to say, the
button 17 will press against the flange 6 with the same force throughout the unwinding operation; but as one continues the pull on the strip 7, the lever arm or distance of the point of contact of the head 17 and the flange 6 from the axis of the shaft 4, will change, due to the fact that the spring keeps the roller 12 pressed on the rolled up strip 7 and moves both the arm 9 and the member 16towards the shaft 4 as the unwinding operation proceeds. Thus the pull on the strip 7 multiplied by the distance of the outer layer of the rolled up strip from the axis of the shaft 4 isopposed by the value of the friction between the head 17 multiplied by the distance of this head from the same point. The moment of. the force or pull to unwind the strip 7 is greatest when the unwinding commences and is then opposed by the moment of the force due to the friction of the member 17 which is also maximum at this point. As the moment of the pull on the strip 7 decreases, the moment due to the friction also decreases and thus the tension on the strip 7 can be kept constant. The roll then unwinds evenly and the strip 7 as it comes ofi the reel 3 is kept stretched at a uniform tension from one end of the unwinding operation to the other.
Having described my invention, what I believe to be new and desire to secure and protect by Letters Patent of the United States is v 1. The combination of a reel from which a strip of rolled material is to be unwound, a friction member to engage the reel and an element rigidly attached to the said member to make contact with the strip of rolled ma terial and regulate the position of said friction member to enable the moment of the force due to the friction to be varied.
2. A tension device comprising a reel, a friction member to engage said reel, an arm rigid with said member to rest upon the surface of astrip wound upon said reel, and a spring normally tendingto urge said arm and said member toward the center of said ree 3. The combination of a base, having an upright support thereon, a reel adjacent said support, a pair of arms in frictional engagement therewith movably supported in spaced relation upon said upright and rigidly'connected to move in unison, and a spring to urge said arms to move their free ends towards the axis of rotation of the reel to said reel and act as a. brake therefor, and
a spring connected to said arms and designed to actuate said arms to move their free ends towards the axis of rotation of said reel. 1
5. The combination of a reel, a roll of material wound thereon, amember engaging the surface of the roll and a co-operatin'g member rigid therewith and in frictional; engagement with the reel, to exert a constant tension on the material during the unwinding thereof.
In testimony whereof I aifix my signature.