US 3275123 A
Description (OCR text may contain errors)
p 27, 1966 D. c. PROSSER ETAL 3,275,123
CONVEYOR BELT WITH CODE ELEMENTS Filed Feb. 27, 1963 INVENTORS. 0,4140 63 P205862 $0605 A pa/v/v/xve, (/2
United States Patent 3,275,123 CONVEYOR BELT WITH CODE ELEMENTS David C. Prosser, Minuetonka Village, and Jacob A. Ronning, Jr., Wayzata, Minn, assignors, by mesne assignments, to Cutler-Hammer, Inc., a corporation of Delaware Filed Feb. 27, 1963, Ser. No. 261,323 2 Claims. (Cl. 198-38) This invention relates to the field of conveyor belt construction and more particularly to conveyor belts which contain code retaining elements.
It is generally well known that conveyor belts are made in numerous ways and of various constructions. Certain conveyor belts are designed to convey loads which are extremely high in temperature and others are designed to operate in the opposite temperature conditions, that is, in freezing weather. Also, conveyor belts have been designed so that they will more nearly conform to concave rollers which are used therewith to reduce spillage. Numerous means have been used to strengthen belts to prolong their wear and usefulness. belts have used wire mesh or lengths of wire running longitudinally with the belt or across the belt to improve the particular operating characteristics desirable in the application for which the belt is to be used.
However, when belts of various types of construction containing metallic elements are subjected to magnetic fields to produce a code therein, the belts which are thus far available have not proven to be satisfactory carriers of the magnetic codes. Magnetic code apparatus combined with conveyor systems such as this, is found in Wales et a]. Patent 3,075,653, entiled Apparatus for and Method .of Identifying Material. It has been found that numerous disadvantages are present when the code detecting apparatus tries to detect a code which is carried by a portion of a longitudinal wire or metallic member in a belt or in a wire which extends perpendicular to the direction of motion of the belt. That is, the magnetic field tends to distribute itself along the entire metallic conductor and if magnetic fields are placed at different locations along the same magnetic code bearing wire or element, there are instances Where a new code is created or the code decays to a point where it becomes unintelligible. It should also be kept in mind that by adding wire or metal to the belt, the belt itself is generally not strengthened in any manner since the material merely surrounds the elements and they provide points of discontinuity running entirely across the belt or longitudinally with the belt. In fact, some attempts have been made to improve the construction of the belts by using plastic threads or cables along the warp of the belt and using metallic elements such as wire in the woof of the belt. Such an arrangement has the disadvantages just described when used with magnetic coding systems. These arrangements of the code heating elements prove to be even more inadequate when a code pattern is used involving a trinary mathematical system. That is, the trinary system as used herein refers to the situation where the magnetic code may either be polarized North-South, South-North, or contain no magnetic polarity. In using this type of coding arrangement, there will be instances where the code area should contain no magnetic signal and the types of belts available heretofore which contain magnetic retaining materials will generally produce some magnetic field in the area where none should appear and thereby produce an erroneous signal to the sensing equipment.
The present invention contemplates confining the code areas to a bit area so that a magnetic state of the area is reliable and will produce a stronger magnetic :Many of the p ice pulse in the sensing equipment for the shorter bit material. More important is the fact that the cross-talk between the magnetic areas is almost eliminated since the code area bits are spatially removed from each other so that magnetic isolation between code channels is effectively accomplished. The so-called bit areas may take on several forms and configurations, some of which will be described in more detail hereinafter. By using materials such as wire staples, small metallic strips or any other material capable of retaining a magnetic field and capable of having the field changed which can be secured to the webbing which forms the belt, such a bit area is produced. It has also been found that by using the materials such as the wire staples or small metallic strips secured to the webbing which forms the belt, the sensing equipment will tolerate more side sway of the belt and thus prove to be more reliable. In fact, the manufacturing of the belt is made much more simple for use with the code sensing equipment where the small metallic elements are used and the belts may then be cut to the desired widths without further trimming of protruding wires on the edges of the belt which is common to those using transverse directed cables or wires.
Another conguration of the material which will retain the magnetic code is one in which the material is formed in a shape similar to an alternating current wave form. That is, the material extends in the long direction of the belt in at least one row or more, but each row also provides short transverse sections of the material which are interconnected between adjacent ends, having been formed of a continuous piece of material or in a continuous manner. Also, for some applications it may also be desirable to form the magnetizable elements from strips of natural or synthetic chemical compounds which have alternate areas of magnetic properties and non-magnetic properties. That is, the strips will form an integral part of the belt in such a manner that columns and rows of code retaining areas are created in the belt. Such areas may also be created by coating the material on the plies and forming the belt by conventional means.
It is contemplated that some applications of the invention will require that certain columns be devoid of a magnetic code retaining area. In other words, one
column will contain three such areas, while the next column will contain magnetic code areas in two rows while the next column will contain magnetic code areas in two rows different from that in the preceding column,
by way of example, or any other combination desired.
It is therefore a general object of this invention to provide a novel conveyor belt for use with magnetic coding apparatus. 7
It is yet another object of the present invention to provide a conveyor belt with reduced metal content and thereby provide a belt with less mass and more flexibility.
It is yet another object of this invention to provide a conveyor belt for use with magnetic coding and sensing equipment having improved bonding of the belt because of reduced metal content.
It is still a further object of the present invention to provide a conveyor belt having magnetic code retaining elements formed therewith.
It is still a more specific object of the present invention to provide a conveyor belt having magnetic code retaining elements secured between plies of the fabric forming the body of a belt.
It is still another object of this invention to provide a conveyor belt having a plurality of magnetic code retaining elements all of which are spaced one from the other.
It is yet another object of this invention to provide a conveyor belt having magnetic code retaining elements formed in columns and rows in the plane of the belt.
These and other objects and advantages of this invention will more fully appear from the following description, taken in connection with the accompanying drawings, wherein like reference characters refer to the same or similar parts throughout the several views, and in which:
FIG. 1 is a cut-away view of a belt section having code retaining elements showing relative placement of the belt with respect to detection and diverter equipment; and
FIG. 2 is another cut-away view of' a belt section showing another form of code element and means for securing it to the belt.
In FIG. 1, a section of a conveyor belt is shown. Belt 10 is shown generally as a section of a fiat endless conveyor belt and it is generally known that such belts are made to conform to the idler rolls or rollers over' The belt is formed from three.
shown, ply 12 is sandwiched between lower ply 11 and.
upper ply 13. It should also be understood that the belt may contain a single'ply or numerous plies of materialdepending upon the requirements of the belt. Se-
cured to ply 12, is a plurality of staples 14 whichare formed into three rows designated A, B, and .C. It will also be seen that the staples 14 are formed in columns such as columns I, H, III, IV, and V. In other words, staples 14 form a pattern designated such as row A, column II. The spacing in each of the rows between the staples may be equal as shown, or staggered, and
isolation from each other. The staples may besecured to one of the plies or several of the plies and may actually be secured where one willappear. in one of the plies, another row in a second. ply, and a third one in another ply. The different plies of reinforcing material are a tension resisting material such as woven fabrics made of cotton, rayon, nylon, glass fiberor the like which do not contain magnetic field retaining properties.
To complete the belt, an elastic non-magnetic material 15 completely encircles and impregnates the plies 11,12,
4 10 to be diverted from the belt 10. The detecting structure and associated apparatus do not form a part of the invention per se but demonstrate the use of the belt in its cooperating capacity to provide the correct magnetic code for diversion of an article. Of course, there would be as many sensing heads as are required for the particular code patterns. v
In some. instances, it may be more desirable to use small -metallic strips such as strips 21 and secure them to ply 12 by other suitable means such as a rubber'coating or cement-22 which will bond with the vulcanized non-magnetic material 15 surrounding the plies and impregnating the plies. 1 1, 12, and 13. It will be noted that the same column and row arrangement is used'as shown in FIG. 1. The method of manufacturing the belt by the use of the present construction is made'uncomplicated by the fact that the ply containing the code bearing elements may be formed first and merely drawn, from a roll of material bearing the elements, between two other plies of material and the entire unit sandwiched into a belt by the vulcanizing or other suitable process. It should also be kept, in mind that the metal staples 14 or code bearing elements 21 maybe fixedly secured to the elastic material should it be desirable to locate the staples or elements upon ply 13.
From the foregoing description and disclosure it will be seen that a new means of providing a conveyor belt for use withimagnetic coding and detecting apparatus has been set forth. It will also be apparent that, by the use of the construction shown and described herein, the conveyor belt is not weakened by an excessive amount of metal contained within the belt. Furthermore, by
, the use of the appropriate spacing of the code retainand 13 of reinforcing fabric so that the entire :struc- I a the staples 14 or other suitable elements placed on the sheet in the same relative positions. as described above, and then folded over eachother and the plurality of plies stitched together to form one load bearing belt Of course, other variations of the. belt may be formed by stitching several separate plies together, any one or all of which has the staples 14 fastened thereto or covering a single ply containing the staples 14 with another sheet encircling the single ply. Thus in this manner, an inexpensive belt may be formed which will operate satisfactorily with a code detecting apparatus.
In order. to detect the code appearing in staples or other similar elements 14, an oscillator 16 provides excitation :to a sensing head 17. Upon sensing head 17 ing elements, an improved magnetic field may be detected which has virtually no cross-talk between .the magnetic elements. It has also been shown that a particular belt construction, is set forth which is particularly well adapted to provide a magnetic code when used with the trinary mathematical system. 7
It will, of course, beunderstood that various changes may be made in the form, details, arrangement and proportions of the parts without departing from the scope of this invention which consists of the matter shown and described herein and set forth in the appended claims. I
What is claimed is: v
1. An endless conveyor belt for extending over a conveyor'frame and driving mechanism and for .use with magnetic coding and detecting apparatus comprising:
(a) a plurality of flat plies of reinforcing non-magnetic woven fabric forming an endless body of tension resisting material having flexibility and adapted for cooperatively engaging the conveyor frame and driving mechanism; 7
(b) a plurality of separated magnetic code retaining 7 elements spaced apart 'so that each is capable of being magnetized with a portion of a code and-retaining a magnetic field for codejsensing purposes until demagnetized, said elements fixedly secured to atleast one of said plies of fabric and arranged in (c) and an elastic non-magnetic material completely encircling and impregnating said plurality of plies of fabric to form a laminated belt with said code retaining elements completely embedded therein.
2. The invention as set forth in claim 1 wherein all of said code retaining elements are disposed withthe longer 5 6 dimension of each of said elongate shapes parallel to that FOREIGN PATENTS of all others- 1,270,105 7/1961 France.
751,689 7/1956 Great Britain. References Cited by the Examiner 5 OTHER REFERENCES UNITED STATES PATENTS Maico Publication: The Basic Mahrol System, P. D. 1 5 21 1 192 1 Sheet No. 103, June 1, 1960. 2 857 059 10/1958 Goerlich.
y 1 L N P 7 3075653 H1963 W ales 198 38 EVON B U rlmwy Exammel 10 WILLIAM B. LABORDE, SAMUEL F. COLEMAN,
3,084,784 4/1963 Zoubek 198 Examzners.
3179241 4/1965 R. E. AEGERTER, Assistant Examiner.