A clutch means particularly useful in the rapid and precise alignment of a large number of rotating members such as take-up reels on a single shaft. Each rotating member, e.g., each reel-hub member, is positively engaged by a resilient and non-fouling spring member which is readily inserted into conventional clutch means and which comprises a cam means to facilitate the sliding passage of a number of reels onto a shaft as well as locking means to couple the clutch means and the reels to be rotated thereon.

BACKGROUND OF THE INVENTION 
This invention relates to improved clutch means and particularly to 
improved clutch means which allow a series of reels to be accurately and 
securely mounted for rotation on a single drive shaft with excellent 
predetermined alignment in the plane of rotation. 
In some industrial processes, it is important to align a number of rotating 
members on a single shaft. In the more critical of such processes, it is 
necessary to assure the smooth driving action of each independent clutch 
mechanism and the avoidance of any wobble or speed difference between the 
rotating members within each mechanism. One such critical application is 
precision slitting of magnetic tape, e.g., computer tape, wherein it is 
absolutely necessary that reels, on which the tape is received from the 
slitter, are free from slip and wobble. Moreover, since a great many reels 
will normally be mounted on a single shaft, it is desirable to be able to 
put them on over the shaft for a considerable distance with no damage to 
the reels which result in eccentric motion of the reel during use. 
Although no prior art has been found which relates to the above-described 
problem, certain clutch mechanisms are described in U.S. Pat. Nos. 
2,713,405 and 2,907,432 which move outwardly to engage, and cause rotation 
of, various members. It is to be noted that this comment on earlier work 
is necessarily made in hindsight and is not intended to imply that it was 
related to the present invention, at the time the invention was made, in 
the eyes of those skilled in the art and who had no knowledge of the 
invention disclosed below. 
SUMMARY OF THE INVENTION 
It is a principal object of the invention to provide improved clutch means 
for securely fastening a large number of reels or other such rotating 
members on a common shaft. 
Another object of the invention is the provision of a novel spring-type 
clutch member which aids obtaining the desired locking of reels on the 
shaft. 
Another object of the invention is to provide an improved apparatus for 
winding a plurality of rolls of magnetic tape on a single shaft. 
Another object of the invention is to provide an improved web packaging 
means for use with slitting equipment. 
Other objects of the invention will be obvious to those skilled in the art 
on their reading of the present description. 
The above objects have been substantially achieved by utilization of a 
combination spring and drive pawl, which provides an excellent positive 
drive connection between wind-up reels and clutch means. They may be 
loaded onto a shaft, within clutch members, without substantial risk of 
damage to either the clutches or reel members mounted thereon. Although 
other leafspring type constructions can be used, the spring-pawl member is 
a single piece pawl member which may be fitted into existing clutch 
mechanisms and which carry a cam operable at right angles to the rotation 
of the pawl. Usually only a portion of a conventional clutch housing may 
be cut away to facilitate assembly of the clutch. However, as will be seen 
in the preferred embodiment, the clutch may also be modified to comprise 
mounting members for the spring. 
The most advantageous drive pawls of the invention are one-piece springs 
formed of engineering plastics such as nylon, polycarbonates or 
polysulfones. Particularly good materials are molded of polycarbonate or 
nylon blended with a small amount of a lubricant like molybdenum 
disulphide or fluoroethylene polymer to decrease the friction 
characteristics of the pawls. 
An important aspect of the invention is the fact that machine productivity 
can be improved markedly by the rapid transfer of reels from and to the 
slitter operating shafts under conditions that assure proper seating of 
the reels on shaft-borne clutches. 
ILLUSTRATIVE EXAMPLE OF THE INVENTION 
In this application and accompanying drawings there is shown and described 
a preferred embodiment of the invention and suggested various alternatives 
and modifications thereof, but it is to be understood that these are not 
intended to be exhaustive and that other changes and modifications can be 
made within the scope of the invention. These suggestions herein are 
selected and included for the purposes of illustration in order that 
others skilled in the art will more fully understand the invention and the 
principles thereof and will be able to modify it and embody it in a 
variety of forms, each as may be best suited to the condition of a 
particular case.

Referring to FIG. 1, it is seen that a clutch member 20 serves as a hub 
means for a reel 22. The connection of clutch 20 and reel 22 is made by a 
drive pawl 24 molded into a spring member 26 and adapted to engage any of 
slots 28 within the reel structure 22. 
In general, the clutch can be selected from many commerically-available 
clutch devices and readily modified by cutting the housing to provide a 
housing slot therein, as at 30, for receiving spring 26. 
As seen in FIGS. 2 and 3, the terminal of spring 26 are slidably positioned 
on pins 32 which themselves are held within wall sections 34 formed by 
slot 30 and exterior slots 36 which form positioning means for a garter 
spring 38 and an O-ring 40. Spring 38 and O-ring 40 bear against, and help 
position, reel 22 on clutch 20. 
Reel 22 is suitably formed of aluminum and can be the general type that 
meets the National Association of Broadcasters specification commonly used 
in reeling film and tape. Presently used hubs have been modified to 
include a knurled interior circumferential wall which, with the aforesaid 
garter spring, forms a mechanical coupling between the reel and the 
clutch. However, in the practice of the present invention, the knurled 
surface has proved to be an undesired abrasive feature and it has been 
replaced with a relatively smooth interior circumferential wall 50 as seen 
in FIG. 4. 
FIG. 4 is an elevation of a reel or hub 22 which is of the type generally 
referred to as a NAB hub, i.e., a hub or reel that meets the aforesaid 
Standard of the National Association of Broadcasters. As is not uncommon 
in such hubs, it is designed for use with a variety of equipment. However, 
of particular interest in the application described herein are outer 
circumferential wall 52 on which magnetic tape or a like tape product is 
to be wound the inner circumferential wall 50 which is to slide over and 
co-operate with a clutch mechanism. Wall 50 comprises three lateral slots 
28 spaced at 120 angular degrees from one another in which the drive panel 
may be received when it is allowed to move outwardly into it normally 
engaged drive position. 
As seen in more detail in FIG. 5, the inner wall, indicated by reference 
numeral 50 in FIG. 4, 50 is not flat but comprises a 25-degree-angled wall 
section 54 near each edge 56. These sections 54 terminate even nearer the 
edge, flat retainer wall sections 58 and finally cam wall portions 70 
angled at 35 degrees to the horizontal. 
Spring member 26 is a resilient elongate spring which engages pins 32. Pins 
32 are slidable within pin support means, i.e., pin slots 60 so that when 
the force is exerted downwardly on pawl 24, spring 26 can readily be 
depressed so that it will slide smoothly beneath the surface 50 of hub 22. 
As seen in FIGS. 7 and 8, pawl 24 comprises cam, or wedge-type faces 62 
which form cam means to aid in depressing the spring with a minimum of 
applied force as it is moved over the cam-bearing clutches, i.e., over a 
series of hubs 22. The leading edge of the pawl 64, however, are not cams 
but are formed to provide bearing surfaces for driving the hub by engaging 
slots 28. 
The illustrated spring 26 is formed of a polycarbonate material or other 
such abrasion-resistant organic resin. Blending a small amount of a 
fluorinated hydrocarbon with the polycarbonate to reduce the coefficient 
of friction has been found to be desirable. 
The drive described herein is an excellent positive drive mechanism. It is 
less susceptible to losing its snug, positive drive characteristics 
because it is relatively insensitive to tolerance deviations in 
manufacture of the hub and to dimensioned change caused by wear on the 
hub. 
The molded one-piece spring coupling means is easy and inexpensive to 
manufacture and resists wear during the repeated sliding of the hubs over 
the clutch assembly. This is true even when the forces exerted on the hubs 
are not precisely parallel to the shaft. Moreover, the spring is highly 
resistant to fouling by metal chips or other debris and resists damage. 
However, if it is damaged, it is readily replaced without taking apart the 
clutch and indeed, even without the required use of tools. 
FIG. 9 is a perspective view of the take-off, or wind-up, end of a slitting 
machine. Strips of slit magnetic tape are wound on reels 22 which are 
mounted, in turn on magnetic clutches 20. It is to be noted that the body 
of spring 26 forms a cover which is a convenient lowfriction replacement 
for clutch housing segment which has been removed to facilitate 
manufacture of the apparatus from a commercially available clutch 
mechanism. 
The reels 22 are mounted on a removable arbor and may be readily lifted 
from the apparatus and quickly and easily removed from the shaft on which 
they are mounted, leaving the clutch-and-spring mechanism on the shaft. 
Conversely, when it is time to place empty reels on the shaft, they are 
readily pushed on, even as a group. 
As shown in FIG. 9, the particular advantage of the invention is realized 
in a precision slitting process wherein a web of magnetic tape is fed into 
a slitting apparatus where the web is converted into a large number of 
tapes of, e.g., about 0.5 -inch width. These tapes are then wound up on 
about NAB hubs of the type described herein. 
The spring and pawl apparatus described herein makes it easy to slide the 
hub over the clutch without paying any attention to the registration of 
the spring and the hub. When the clutch is rotated, however, the springs 
are quickly, i.e., within a 120.degree. arc, brought into engagement with 
a drive slot 28. 
The clutch is preferably a magnetic clutch and forms a torque limiting 
means for the winding operation. 
It is also to be understood that the following claims are intended to cover 
all of the generic and specific features of the invention herein described 
and all statements of the scope of the invention which might be said to 
fall therebetween.