Apparatus for monitoring the delivery of material

An apparatus for monitoring the delivery of material from a spool or the like to a machine which is to perform some work upon the material and draws the material from the spool. The apparatus includes a shaft for accommodating and fixedly securing the spool thereon, apparatus for positioning the shaft at a predetermined location wherein the positioning apparatus also permits the free rotation of the shaft about the longitudinal axis thereof, apparatus for providing a pulsed electrical signal upon rotation of the shaft, the pulsed electrical signal device having an element thereof directly coupled to the shaft for rotation as a result of the rotation of the shaft, and apparatus for indicating the output of the pulsed electrical signal device wherein the apparatus which does work on the material can be shut off if the material being fed from the spool becomes tangled, snarled, or otherwise jammed or is consumed.

BACKGROUND OF THE INVENTION 
1. FIELD OF THE INVENTION 
The present invention relates to devices for monitoring the unwinding of a 
length of material from a spool means, and more particularly to a 
monitoring apparatus wherein turning of a shaft means which mounts the 
spool means directly participates in the generation of a pulsed electrical 
signal for controlling a device for performing work on the length of 
material used in association with the monitoring apparatus. 
2. DESCRIPTION OF THE CONTEMPORARY AND PRIOR ART 
There are several different applications in the sewing industry where 
lengths of material must be delivered to automated equipment so that work 
can be done on the material or so that the material can be used as a part 
of a manufacturing or assembling operation. It is important that the 
supply of material be monitored so that damages in the material, knots, 
and material tangles as well as malfunctions which cause equipment to 
cease to demand material can be timely sensed so that equipment can be 
preferably automatically shut down without operator intervention. In 
addition, it is also desirable to provide for the shutdown of automated 
equipment when the material being fed to that equipment is consumed. 
Various apparatuses have been proposed in the prior art for accomplishing 
some or all of these either independently or together. However, 
apparatuses presently known tend to be expensive and have several 
drawbacks including frequent breakdowns attributable to contamination from 
dust, fibers, or chemicals used on the material which is being monitored. 
These problems arise primarily from contact between the sensing mechanisms 
of the monitors and/or the interaction between the material and the way 
the monitors sense the presence of material. Some limited function 
presently known devices for monitoring the delivery of material use 
mercury switches to test for the tension in the material or use 
photoelectric cells to sense the presence of material. However, these 
devices can only sense the presence or absence of material, not a jammed 
condition which is in most instances more important in terms of potential 
damage to machinery. 
U.S. Pat. No. 3,177,749 issued to K. J. Best et al on Apr. 13, 1965 teaches 
a control for feeding, measuring, and cutting strip material wherein a 
wheel having a plurality of apertures disposed therethrough interrupts a 
light source which is focused on a light sensitive element. This 
counterwheel makes contact with the material passing through the apparatus 
through use of a pressure wheel which sandwiches the material between the 
pressure wheel and the counterwheel. As a result, material contact is not 
avoided and the attendant problems associated therewith are incurred. A 
perforated wheel which interrupts a light source shining on a light 
receptor hooked to an electronic counter is also shown in U.S. Pat. No. 
3,550,493 issued to W. J. Benbenek on Dec. 29, 1970; U.S. Pat. No. 
3,556,368 issued to P. L. Runde on Jan. 19, 1971; United E. H. Streckert 
on Dec. 17, 1969; U.S. Pat. No. 3,715,944 issued to W. J. Knechtel et al. 
on Feb. 13, 1973. Additionally, such a configuration is used by U.S. Pat. 
No. 3,170,667 issued to J. N. Kluger on December 14, 1970 to monitor the 
movement of a web. However, each and every one of these apparatuses 
depends upon contact between the material or web which is handled and 
either a counting wheel or an associated friction roller or the like to 
create a pulse. 
The present invention overcomes, inter alia, the disadvantage of having a 
pulse forming mechanism frictionally engage the material which is to be 
monitored. This is accomplished through the direct coupling of an element 
of a pulsed electrical signal generation providing means with the rotating 
shaft which supplies a length of material wrapped around a spool means 
disposed on the shaft so that rotation imparted to the shaft by removal of 
the length of material from the spool means provides a pulsed electrical 
signal without contact with the material being monitored. 
Unlike the above mentioned devices which simply count pulses (to determine 
length), the present device acts on pulses via a timing means. Time 
intervals between pulses are measured so that state of motion or no-motion 
can be determined. 
SUMMARY OF THE INVENTION 
Object of the present invention is to provide an apparatus for monitoring 
the delivery of material wherein material runout and snagging, jamming, 
malfunction of associated equipment or the like can be detected. 
A further object of the present invention is to provide an apparatus for 
monitoring the delivery of material from a spool means which is not 
dependent upon gravity and which therefore can be used regardless of the 
orientation of the material to be monitored. 
Still another object of the present invention is to provide an apparatus 
for monitoring delivery of material from a spool means wherein direct 
contact between the material to be monitored and the monitoring means is 
entirely avoided. 
Another still further object of the present invention is to provide an 
apparatus for monitoring the delivery of material from a spool means which 
can shut off associated equipment when a predetermined condition is 
satisfied by the material which is monitored. 
Still another object of the present invention is to provide an apparatus 
for monitoring the delivery of material from a spool means which can 
accommodate variously sized and dimensioned spool means without 
substantial variation of elements or modification of structure or 
assembly. 
Still another object of the present invention is to provide an apparatus 
for monitoring the delivery of material from a spool means wherein the 
apparatus does not have to be adjusted or modified when different types of 
materials are monitored. 
Still another object of the present invention is to provide an apparatus 
that will maintain the associated equipment in a safe off condition until 
manually reset by the equipment operator. 
Another object of the present invention is to provide an apparatus for 
monitoring the delivery of material from a spool means which is simple in 
design, relatively inexpensive to manufacture, rugged in construction, and 
virtually maintenance free. 
These objects, as well as further objects and advantages of the present 
invention, will become readily apparent after reading the ensuing 
description of the nonlimiting embodiment and viewing the accompanying 
drawing. 
An apparatus for monitoring the delivery of material from a spool means 
according to the principles of the present invention includes shaft means 
for accommodating and fixedly securing the spool means thereon, means for 
positioning the shaft means at a predetermined location relative to a 
supporting surface, the positioning means permitting the free rotation of 
the shaft means about the longitudinal axis thereof, means for providing a 
pulsed electrical signal upon rotation of said shaft means as a result of 
the drawing of material from said spool means, the pulsed electrical 
signal means having at least one element thereof directly coupled to the 
shaft means for rotation as a result of the rotation of the shaft means, 
and means for indicating the output of the pulsed electrical signal means.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the figures, and more particularly to FIG. 1 thereof, 
there is illustrated therein an apparatus 10 monitoring the delivery of a 
material 12 from a spool 14 to a strip cutting apparatus 16. Although the 
apparatus 10 is illustrated for use in conjunction with the strip cutting 
apparatus 16, it may be used for other types of equipment or machinery 
which require the delivery of a length of material or web. 
The strip cutting apparatus 16 which has been selected for purposes of 
illustration is disclosed in U.S. Pat. No. 4,056,025 and has common 
inventorship with the present invention. 
The apparatus 10 includes a spool mounting assembly 18 and a control box 20 
connected together with a multiconductor electrical cable 22. The strip 
cutting apparatus 16 is provided power through a cable 24 that is 
connected to the control box 20 for delivery of electricity thereto as 
hereinafter described. Electricity is supplied to the control box 20 and 
therefore the spool mounting assembly 18 as well as the strip cutting 
apparatus 16 by a line cord 26. Control box 20 has mounted thereon a pilot 
light 28 and an on-off switch 30 connected to the line cord 26 in a 
conventional manner as illustrated in FIG. 5. In addition, a reset switch 
is mounted on the control box 20 which functions as hereinafter described. 
Also, there can be provided a knob to control sensitivity to match 
characteristics of machine being monitored. The control box 20 also serves 
as a housing for a substantial portion of the electronics of the present 
invention as will be described in conjunction with FIGS. 4, 5, and 6. 
The spool mounting assembly 18 has a support 34 fixedly secured thereto to 
aid in positioning of the assembly 18. In addition, a rotating shaft 36 is 
provided by the spool mounting assembly 18 and serves to mount the spool 
14. Although a particular size and shape spool 14 is illustrated, spools 
of various configurations and sizes can be mounted by the present 
invention as long as they permit delivery of material therefrom. As will 
be described in detail, the apparatus 10 essentially serves to monitor the 
feeding of material 12 to the strip cutting apparatus 16, or another 
machine of the user's choice, such that tangles, snags, knots or other 
problems which will preclude feeding of the material 12 to the apparatus 
16 or consumption of the material 12 and subsequent emptying of the spool 
14 will cause the apparatus 10 to cut off power both to the strip cutting 
apparatus 16 or the like and to the apparatus 10 until the condition is 
corrected and the reset button 32 is pressed by the user to restore the 
entire system to operation. 
With reference to FIG. 2, the spool mounting assembly 18 is fixedly secured 
to the support 34 by at least one suitable fastener 38. The support 34 is 
illustrated as extending through the housing portion 40 of the spool 
mounting assembly 18 for rigidity, but other suitable arrangements can be 
employed so long as the housing portion 40 is rigidly secured to the 
support 34. A "C" clamp 42 is fixedly secured to an end of the support 34 
and serves to clamp the support 34 and therefore the spool mounting 
assembly 18 to a supporting surface S. Typically, supporting surface S 
will be a machine table or the like. It should be apparent to one skilled 
in the art that other than a "C" clamp can be employed and that such 
substitute mounting for the "C" clamp 42 can be clamped to a supporting 
surface located in variously disposed planes. 
The rotating shaft 36 provided by the spool mounting assembly 18 is 
disposed through a pair of aligned apertures located in the housing 
portion 40 and is supported by a pair of bearings 44 which permit free 
rotation of the shaft 36 about the longitudinal axis thereof. The shaft 36 
is further supported as will be subsequently described. In order to 
accommodate spools having different internal diameters, a first section 46 
of the shaft 36 is of one diameter and a second removable section 48 of 
the shaft 36 is of a second diameter. The second section 48 is removably 
secured to the first section 46 by a threaded coupling 50 fixedly secured 
to the second section 48 and which threadably cooperates with a threaded 
portion 52 adjacent to one end of the first section 46 of the rotatable 
shaft 36. The second section 48 can be engaged or disengaged from the 
first section 46 as desired. Similarly, other schemes or configurations 
can be employed for attaching different diameter shafts or other mounting 
structures for a spool. 
Considering FIG. 3 along with FIG. 2, it can be seen that the rotating 
shaft 36 is additionally supported by a ball bearing assembly 54 fixedly 
secured to the housing portion 40 of the spool mounting assembly 18. The 
ball bearing assembly is a sealed unit but other suitable bearing 
assemblies can be employed. The exact bearing assembly which is used and 
the bearings or journals which are employed where the rotating shaft 
extends through the housing portion are unimportant so long as the 
rotating shaft 36 is fixed into position and can support the weight of the 
spool 14 and simultaneously is freewheeling so that it can rotate about 
the longitudinal axis thereof. A pulse generator 56 has a disk portion 58 
thereof fixedly secured to the shaft 36. The disk 58 has a plurality of 
apertures 60 disposed therethrough which are arranged in a circular 
pattern. The disk 58 is straddled by a horseshoe shaped assembly 62 which 
serves to mount a light source 64 such as a photodiode or similarly 
functioning component and a light receptor 66 such as a photo-transistor 
or the like. 
The light source 64 is positioned within the assembly 62 so that it is 
directed at the light receptor 66 and the assembly 62 is fixedly secured 
to the housing portion 40 of the spool mounting assembly 18 so that the 
assembly 62 is positioned in such a manner as to permit the apertures 60 
disposed in the disk 58 to permit light to shine from the light source 64 
on the light receptor 66 and for this light to be interrupted upon 
rotation of the disk 58 as a result of the rotation of the rotating shaft 
36. The light source 64 and the light receptor 66 are operably connected 
to an electronic sensing network 68 which will hereinafter be fully 
described in conjunction with FIGS. 4, 5, and 6. The electronic sensing 
network 68 may be disposed entirely within the housing portion 40 or some 
of the components thereof can be disposed within the control box 20 
illustrated in FIG. 1. The provision of a separate housing poriton 40 and 
a control box 20 is one of convenience so that the on-off switch 30 and 
the reset switch 32 can be located in a position remote to that of the 
housing portion 40, but this provision is not essential to the invention 
and other housing configurations can be used as determined by one skilled 
in the art. 
The spool 14 which is illustrated in FIG. 3 is an arbitrary shape and may 
vary accordingly to different needs. Likewise, the material 12 is also 
shown in arbitrary dimensions and may be of various widths and 
cross-sectional dimensions and shapes as required. The common relationship 
between the spool 14 and the material 12 is that the material 12 is wound 
therearound for delivery therefrom. The spool 14 can be secured to the 
rotating shaft 36 in many manners by variously configured latches, clamps, 
etcetera and is illustrated as being held in position on the shaft 36 by a 
pair of conical clamps 72 which each serve the purpose of engaging the end 
panels of the spool 14. Each of the clamps 72 also provide a locking screw 
74 to fix the position of the clamps 72 on the shaft 36. As the material 
12 is drawn from the spool 14, the shaft 36 is urged into free rotation 
and the pulse generator 56 is urged into action without any contact 
between the pulse generator 56 and the material 12 so that the material 12 
does not need to be abused in any manner whatsoever nor is it in any way 
subjected to detrimental contact that inevitably results from friction 
type material monitors. 
The pulse generated by the pulse generator 56 is utilized to monitor the 
delivery of the material 12 from the spool 14 as a result of the circuitry 
illustrated in FIG. 4. The fixed light source 64 and the light receptor 66 
are schematically illustrated with an interruptor means embodied by the 
disk 58 disposed therebetween. The output of the pulse generator 56 is in 
the form of a pulsed electrical signal and is coupled to a first timing 
means 76. The output of the first timing means 76 is coupled to the input 
of a second timing means 78 and the output of the second timing means 78 
is coupled to a preferably solid state relay. The output of the first 
timing means 76 provides an electrical signal at a first level for a 
finite time when the rotating shaft 36 rotates as a result of the disk 58 
interrupting the beam of light between the fixed light source 64 and the 
light receptor 66. When the rotating shaft 36 rotates at a speed below a 
preselected minimum or if it is at rest, the first timing means 76 
provides an output at a second level. The output of the first timing means 
76 returns to the second level after the finite interval. This finite 
interval can be predetermined to be less than or equal to the minimum time 
required for one of the apertures 60 to pass through the light beam formed 
by the fixed light source 64 until the next aperture 60 appears in the 
same position when the shaft 36 is rotating at its minimum desired speed 
as correlated with the demand of the apparatus 16. 
The previously described output of the first timing means 76 is fed to the 
second timing means 78 which provides a signal at the output thereof if 
the signal of the first timing means 76 is not received by the second 
timing means 78 at a preselected interval. When the second timing means 78 
provides a signal at the output thereof, it is fed to the relay 80 to open 
the contacts 82 thereof. A preselected interval of no signal in after 
which an output signal is provided by the second timing means 78 may be 
fixed or variable depending upon the needs of the apparatus or machine 16. 
Since the machine 16 being monitored might well operate at different 
speeds, this interval prior to shut off can be adjustable using suitable 
electronic circuitry well known in the art. The relay 80 may be normally 
open or normally closed depending upon the exact manner in which the 
electronic sensing network 68 is to control the machine or apparatus 16. 
The A.C. power line 84 is fed past the power switch 30 and the pilot light 
28, wired in a conventional manner, to the contacts of the relay 80 and 
the reset switch 32 which is in parallel with the relay contacts 82. The 
relay contacts 82 are in series with the A.C. line in 84 and feed both the 
power supply 86 for the electronic sensing network and the apparatus 16. 
Therefore, when the second timing means 78 causes the relay 80 to open the 
contacts thereof, power to the machine or apparatus and the power supply 
86 and therefore the electronic sensing network 68 are killed. This would 
happen if the disk 58 slows down in rotation beyond the preselected speed 
of if the disk 58 stops in any position relative to the light from the 
fixed light source 64 shining on the light receptor 66. The reset switch 
32 is provided to bypass the relay contacts 82 so that once the electronic 
sensing network 68 and the apparatus 16 are shut down and the problem 
which caused the shutdown is cured, the system can be started up again 
simply by pressing of the reset switch 32. With this configuration, 
apparatus 16 can not falsely operate until the operator uses reset switch 
32. 
The manner in which the apparatus being monitored 16 and the electronic 
sensing network 68 are provided with the line current 84 is illustrated in 
the wiring diagram of FIG. 5. The on-off switch 30 breaks both sides of 
the A.C. line in 84. When the switch 30 is closed, the pilot light 28 
which is across the switch 30 is activated. One side of the A.C. line 84 
is then fed to one of the relay contacts 82 and to one side of the reset 
switch 32. The other side of the A.C. line is fed to the apparatus 16 and 
one side of the primary winding of a transformer 88. When the relay 
contacts 82 are in a closed position or when the reset switch 32 is 
closed, the first side of the A.C. line is then fed to the other side of 
the primary winding of the transformer and to the apparatus 16. The 
secondary of the transformer 88 is connected to the power supply 86 for 
the electronic sensing network. The electronic sensing network 68 controls 
the coil 90 of the relay 80, or the electronic equivalent thereof, so that 
the function previously described can be implemented. 
It should be apparent to one skilled in the art that the electronic sensing 
network 68 and the pulse generator 56 thereof can be variously configured. 
The first and second timing means 76 and 78 can take many forms and can 
easily be placed on a single IC chip. A possible configuration for this 
chip or otherwise implemented circuit is illustrated in FIG. 6. The first 
timing means 76 is seen to comprise a comparator 92 which is coupled to a 
monostable multivibrator 94, the comparator 92 being fed by the receptor 
66. The second timing means 78 is fed by the first timing means 76 and 
comprises a delay timer 96 and a comparator 98. The delay timer 96 feeds 
the comparator 98 which in turn feeds the solid state relay 80 so that the 
desired control functions relating to the apparatus 16 being monitored can 
be accomplished. Other timing means aside from those illustrated can be 
employed in conjunction with a pulse generator configured as pulse 
generator 56 or otherwise, the essential feature being that an element of 
the pulse generator, in this case, the disk 58 acting as an interruptor 
means is directly coupled to rotation of the rotating shaft 36. For 
instance, a magnet and inductor system could be substituted for the pulse 
generator 56 or any other device which translates rotation of the shaft 36 
into pulses. Similarly, the first and second timing means 76 and 78 are 
meant to be merely illustrative of one way that the pulses provided by a 
pulse generator cooperating with the rotation of the shaft 36 can be 
properly interpreted within preselected design constraints to operate 
relay 80 and therefore control operation of the apparatus 16. 
Substitutions or modifications in the pulse generator 56 and the first and 
second timing means 76 and 78 are within the scope of the present 
invention. 
It will be understood that various changes in the details, materials, 
arrangements of parts and operational conditions which have been herein 
described and illustrated in order to explain the nature of the invention 
may be made by those skilled in the art within the principles and scope of 
the invention.