Strip material take-up apparatus

A device for rolling up strip material such as paper on a reel or spool for temporary storage purposes, which maintains a relatively uniform tension on the strip material regardless of the movement of that strip material, is disclosed and employs an electric motor which exerts a substantially constant torque independent of the speed of motor operation, which motor is positively drivingly coupled to an expanded mandrel for receiving the strip material. When the mandrel strip material capacity is reached, it may be removed and an end flange extracted therefrom allowing the mandrel to collapse, facilitating the removal of the roll of strip material. In a preferred embodiment, the positive drive is achieved by a toothed timing belt in conjunction with a pair of corrugated pulleys, one coupled to the motor rotor and the other journalled in axial alignment with the mandrel. In this preferred form, the mandrel or spool is formed as a hollow cylindrical core, slotted axially part way therealong with peripherally adjacent slots extending from opposite core ends and with a pair of constricting O-rings surrounding the core so as to collapse the slots. A pair of reel ends or flanges each having an axle portion insertable into the cylindrical core so as to expand that core somewhat against the constricting force aid removal of wound strip material from the mandrel.

BACKGROUND OF THE INVENTION 
Field of the Invention 
The present invention relates generally to an apparatus for rewinding strip 
material as that material becomes available and more particularly to a 
comparatively simple arrangement for taking up such strip material in 
environments where the strip material becomes available for rewinding 
during irregularly occurring intervals and at variable speeds during those 
intervals. Even more particularly, the present invention relates to a 
strip take-up apparatus which exerts a relatively constant tension on the 
strip material regardless of the material feed rate. 
A number of diverse strip material take-up reel arrangements are known and 
typically these arrangements are integral with the device making the strip 
material available. Classic examples are incorporated in magnetic tape 
recorders, motion picture projectors, cash registers which maintain a 
paper tape record of all transactions and conventional typewriter ribbon 
mechanisms, as well as numerous special purpose machines such as medical 
and seismic recording machines. 
There are also a number of types of machines which generate strip material 
such as a paper tape printed output from a computer or calculator, as well 
as the printed output of automated typewriters and other business 
machines. The problem of retention and storage of such strip material 
records remains in part unsolved and the number of different attempts to 
take-up and store such strip material bears eloquent testimony to the 
unsolved nature of the problem. The auxiliary strip material rereeling 
proposals heretofore typically employ some sort of clutching mechanism 
between a power source and a take-up reel to compensate for variations in 
the rate of strip material movement. Such clutching arrangements are 
subject to wear, particularly when strip material movement ceases yet the 
drive continues. Such strip material take-up arrangements also typically 
employ a core about which the material is to be wound and when removing a 
reel of strip material, a new core must be positioned in the device 
preparatory to receiving additional material. The prior art attempts have 
also typically been relatively expensive and complex both from a 
maintenance and a user's point of view. It therefore would be highly 
desirable to provide an operationally simplistic and economical strip 
material take-up apparatus adaptable to a wide variety of paper and 
similar strip material handling problems. 
SUMMARY OF THE INVENTION 
Among the several objects of the present invention may be noted the 
elimination of the above-mentioned defects and achievement of the 
above-mentioned goals; obviating clutch wear and the associated problems 
in typical take-up reel devices; facilitating removal of a roll of strip 
material from the mandrel or arbor about which that material has been 
rolled; and the provision of a strip material take-up apparatus 
characterized by its ease and economy of manufacture and maintenance as 
well as its adaptability to a wide variety of strip material take-up 
problems. These as well as other objects and advantageous features of the 
present invention will be in part apparent and in part pointed out 
hereinafter. 
In general, a strip material take-up apparatus includes a drive motor 
having an applied voltage-dependent torque which is substantially 
independent of the speed of operation of the motor, positively drivingly 
coupled to an expandable mandrel for receiving, in its expanded condition, 
the strip material so that the mandrel may wind strip material thereabout 
as the material becomes available, while maintaining a substantially 
constant tension on the strip of material in a manner independent of strip 
material movement. 
Also in general and in one form of the invention, the strip material 
take-up apparatus includes a hollow cylindrical core with expansion slots 
extending axially from one end face thereof toward and terminating short 
of the opposite core end face with peripherally adjacent slots extending 
from opposite core end faces, along with a pair of end flanges having axle 
portions insertable into the cylindrical core to expand the slots against 
a circumferentially constricting force so that removal of the end flanges 
allows collapse of the core and the easy removal of strip material wound 
thereabout. A drive arrangement which imparts a substantially constant 
torque to the strip material receiving reel and an operator actuable 
control for varying that torque are also provided.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring first to FIGS. 1 and 2, the strip material take-up apparatus of 
the invention is seen to include an expandable mandrel 11 which is in its 
expanded state whenever end flanges 13 and 15 are in position as 
illustrated in FIG. 1. In this state the mandrel is ready to receive strip 
material such as paper fed from an intermittently operating business 
machine. Mandrel 11 is supported for rotation about its axis at one end by 
shaft 17 rotationally supported in bracket 19 and engaging a hole in the 
outer end face of flange 15 while flange 13 has a similar opening for 
receiving shaft 21. For example, the shafts 21 and 17 may be provided with 
hexagonally shaped heads and the respective flanges 13 and 15 may be 
provided with mating hexagonal holes. 
Shaft 21 is supported by bearings in the upright members 23 and 25, 
respectively, and may move axially within those bearings toward the right 
as limited by engagement of the shaft 21 with mandrel 11 while leftward 
movement, as viewed, is limited by engagement between upright member 25 
and shaft supported snap-ring 27 as shown in FIG. 2. Shaft 21 is biased 
toward the right, as viewed, by a coil spring 29 so that an operator may 
grip and pull shaft knob 31 toward the left to disengage shaft 21 from 
flange 13 whereupon the mandrel 11 is moved toward the left slightly to 
disengage shaft 17 from flange 15 with removal of the mandrel and 
subsequent replacement being readily accomplished by operator compression 
of the spring 29 and simple alignment or removal of the respective shafts 
and flange openings. Shaft 21 also has fixed thereto a drive wheel or 
pulley 33 having a corrugated or toothed peripheral surface 35. 
A similar drive wheel 37 and corrugated drive surface 39 is fixed to the 
shaft 41 of the rotor of electric drive motor 43. Drive wheels 33, 37 are 
drivingly connected by toothed drive belt 65. Thus rotation of the motor 
rotor positively drives mandrel 11 as illustrated in FIG. 1. Drive motor 
43 is of a type which exerts a relatively constant rotor torque 
substantially independent of the motor speed of operation even in a 
totally stalled condition. While called relatively constant herein, such 
motors frequently exhibit maximum torque in a stalled condition with that 
torque falling off somewhat as the speed increases. Such motors are 
commercially available and a KC1-26 Model 621 motor manufactured by Bodine 
Electric Company of Chicago, Ill., has been successfully used in a 
preferred embodiment. For example, a polyphase hysteresis motor may be 
connected for single phase operation, using a phase splitting capacitor 
45. Other types of induction motors may also be used. While rotor torque 
is nearly independent of the speed of rotation of the rotor, this torque 
varies directly with the applied voltage approximately as the square of 
that voltage and a rheostat 47 with operator actuable control knob 49 may 
be connected in the circuit so that the operator may select a preferred 
strip material tension for a specific task. As illustrated in FIG. 1, a 
three conductor single phase alternating current source line passes 
through grommet 51 with conductor 53 grounded for safety reasons and line 
55 connected to one terminal of rheostat 47. The other terminal of 
rheostat 47 is connected by way of lines 57 and 59 to one side of each 
phase of a two phase stator winding within the motor 43. The other lead 
for one phase is coupled by way of conductor 61 to one side of the 
capacitor 45 while the remaining lead for the other phase is connected to 
the other terminal of capacitor 45 and thence to the other power input 
lead 63. Thus, the operator may, by manipulating control knob 49, vary the 
voltage applied to the motor 43 thereby controlling the rotor torque 
thereof and, by way of timing belt 65, also controlling the tension on 
strip material being wound about the arbor or mandrel 11. This mandrel or 
arbor functions as the strip material accumulation reel and the details 
thereof are best seen in FIGS. 3 through 7. 
Referring primarily to FIG. 6, the arbor 11 includes flanges 13 and 15 
having respective axles 67 and 69 which may include a non-slip surface as 
at 71 and a taper 73 to facilitate entry of the axles into the cylindrical 
core 75. The hollow cylindrical core 75 is provided with eight axially 
extending slots as illustrated, which slots extend from end faces 77 and 
79, respectively, of the core toward the opposite end face, however, the 
slots terminate short of the opposite end face so that adjacent slots such 
as 81 and 83 extend in opposite directions from opposite core end faces. A 
pair of O-rings 85 and 87 in circumferential slots 86, 88, respectively, 
tend to constrict the cylindrical core 75, closing the respective slots as 
depicted in FIGS. 6 and 7. Positioning the axles 67 and 69, as illustrated 
in FIG. 3, expands the core 75 against the circumferentially constricting 
force of O-rings 85 and 87, expanding the slots as illustrated in FIGS. 4 
and 5. Thus with the axles in position within the cylindrical core, paper 
or other strip material may be wound about that core and thereafter the 
operator may remove the two end flanges 13 and 15 causing the cylindrical 
core to collapse, allowing its free removal from a reel of strip material 
for reuse. 
Thus, from a user's point of view, control knob 49 selects a speed 
independent torque and, therefore, a speed independent tension on the 
strip material being received while knob 31 functions as a release 
mechanism for placement or removal of the arbor 11. Simple removal of the 
axles 67 and 69 collapses the cylindrical core 75 to release it from an 
accumulated roll of strip material. Adaptation of the device to accumulate 
strip material of various widths may in some cases require the use of a 
reel of different axial length, and bracket 19 may be moved relative to 
the remaining apparatus by simply loosening screws 89 and 91. 
From the foregoing it is now apparent that a novel strip material take-up 
apparatus meeting the objects and advantageous features set out 
hereinbefore as well as others has been disclosed and that modifications 
as to the precise configurations, shapes and details may be made by those 
having ordinary skill in the art without departing from the spirit of the 
invention or the scope thereof as set out by the claims which follow.