US2272883A - Method of making fan belts - Google Patents

Description

Fel 10, 1942- w. E. HAGGAN L I 2,272,383

METHOD 0F MAKING FAN BELTSV Filed July 22, 1938 ggf . l A 2 4* 2f VN.

f w Vl 24N ATTORNEY Patented Feb. 1o, 1942 METHOD oF MAKING FAN BELTS William E. Haggan, Barberton, Ohio, assignor to The Firestone Tire & Rubber Company, Akron, Chio, a corporationof Ohio Application July 22, 1938, Serial No. 220,729

. 3 Claims.

This invention relates to belts, more especially `to methods and apparatus for manufacturing fan belts and to the fan belts produced.

Customarily in the manufacture of small belts, such as fan belts, a plurality of belts are simultaneously built upon a drum from sheets of material. In this mass production the reenforcing cord for the nished belt is uniformly Wrapped around the drum with the convolutions of the cord being immediately adjacent. Thereafter the individual fan belts are cut from the cylinder of material built. upon the drum and certain of the cords are cut and/or exposed. This necessitates covering the fan belts prior to their use for otherwise the cords rapidly fray out from the fan belt and destroy its usefulness.

One object of this invention is to overcome the foregoing and other disadvantages attendantv the use of known methods and machines for y manufacturing fan belts and, to provide a novel,

easily practiced method of constructing fan belts, which method eliminates construction costs of the prior art.

Another object of the invention is to produce abelt in which the reenforcing cords therein are totally embedded in the body of the belt.

Another object is to provide belts which are resistant to transverse compression and circumferential elongation while also' being suitably exible circumferentially.

Another object is to provide apparatus for positioning a vpredetermined number of cords immediately adjacent each other and then skip an appreciable space prior` to depositing a second set ofadjacent cords.

The foregoing and other objects are achieved by placing a layer of belt stock upon a collapsible form and winding spaced sets of convolutions of reenforcing cord upon the belt stock. These cords are covered with more belt stock and the individual belts are cut from the form at the portion of the stock between the sets of convolutions of cord. This cuts and/or exposes portions of the reenforcing cords, which portions are -secured in the belts in any suitable manner in the process ofv constructing fan belts, with a portion of the belt stock plies cut away;

Figure 4 is a perspective view ol a portion of the finished fan belts; and e I Figure 5 is a detail elevation of the cam means after arcuate movement of the cam with relation to the cam plate has occurred.

Referring specifically to the drawing, a frame I0 is provided to support and journal a threaded shaft II. The threaded shaft I I is driven by any suitable means, not shown, which connects thereto at the clutch I2. A threaded sleeve I3 having an annular flange I4 intermediate its ends engages with the threaded shaft Il and thereby is driven across the threaded shaft II by the shafts rotation. A second, or keyed, shaft I5 carrying a key I6 is also journalled in the frame II). This shaft I5is driven in the same direction as the threaded shaft II and at a predetermined relative speed thereto through a gear I'I on the threaded shaft. This gear engages with a gear I8 on a shaft I9 which is journalled in a gear positioning arm 2|. The arm 2| is rotatably carried by the .threaded shaft whereby the relative position of the shaft I9 andthe keyed shaft I5 can be varied as desired. The movement of the shaft I9 is limited byy an arcuate slot 22 in which the shaft is received. A gear 23 is also carried by the shaft IS and it engages with a gear 24 on the keyed shaft I5. By varying the position of the shaft I9 inthe slot 22, varying sized gears may be substituted for the gear 23 to drive thekeyed. shaft I5 at a desired relative speed through'the threaded shaft II, and the shafts may be disengaged b'y such arcuate movement, when desired. In all events, the shaft II is driven a predetermined number of complete process of constructing the belts `to prevent them from protruding from the finished belt whereby a belt having the reenforcing cords totally embedded therein can be produced.

In the accompanying drawing;

Figure 1 is an elevation of apparatus for practicing the invention;

Figure 2 is a detail elevation takeny on line 2-2 of Figure 1;

Figure 3 is an elevation of a drum used in the `erally on the shaft.

revolutions faster than the shaftv I5 for a purpose later to be explained.`

The keyed shaft I5 carries a grooved sleeve 25 which engages with the key I B and thereby rotates with the shaft I5 although the key connection permits the grooved sleeve 25 to move lat- A substantially U shaped bracket 26 engages'with the threaded sleeve I3 and the grooved sleeve 25 and is slidably carried thereby with the arms thereof parallel to the shafts II and I5. also slidably carried by the sleeves I3 and 25, being positioned adjacent the forwardv side of the ange I4 with relation to4 its normal movement. The bracket 26 carries -a guide pulley 28 over which the reenforcing cord' is led on to the fan belt stock whereby the bracket 26 must be given the intermittent motion required to lay the re- A carriage member 21 is and these means include an annular cam plate 29 whch is carried by a base member 3l. The base member 3| is secured to the ends of the arms of the bracket 26 so that the cam plate 29 encircles the keyed shaft I5. A cam 32 is carried by and rotates with the grooved sleeve 25. The cam 32 is provided with a predetermined number of small steps, or notches 33 therein which are progressively farther from the base of the cam, the circuit of the cam being completed by the formation of a large step, or notch therein. In the apparatus illustrated, the cam and cam plate each have four steps therein; Figure 1 showing the carn as it initially engages the cam plate, which has a cam surface corresponding to the cam 32. A "spring 35 is carried by the vgrooved sleeve 25 between the bracket 26 and the carriagemember 2'I to urgeuthe bracket 26 forwardly with relation to the lateral movement of the threaded sleeve I3 and the carriage member 2l associated therewith.

In operation, the threaded `shaft II' drives the threaded sleeve I3 laterally at a uniform rate. Simultaneously the keyed shaft I5 is being rotated at `a fraction of the speed of the shaft II whereby the cam `32 is retarding the forward movement of the cam plate 29 and the bracket 26 with the threadedsleeve by forcing the cam plate 29 and bracket assembly in the opposite direction with relation to the lcarriage member 21. The oam's action prevents the forward movement of the guide pulley 28 from being equal to that of the sleeve I3, and compresses the spring 35 for the spring bears upon the carriage member 2'I which is held against rearward movement by the flange I4. Then when the large step in the cam 324` is in proper i rotative position relative to the cam plate, the

bracket 26 is freed for a substantial forward A movement. Thus the spring 3,5, being compressed by the previous cam action, forces the bracket 26 to jump forwardly relative to the movement of the threaded sleeve. This results in a plurality of reenforcing cords 38 being laid immediately adjacent each other either intouching relation or slightly spaced in the fan belt stock, as shown in Figure 3, and then having the apparatus skip an appreciable space prior to again depositing, by winding, a predetermined number of adjacent cords 38. The sleeve 25 offers sufIicient resistance to longitudinal movement on the keyed shaft I5 andthe spring 35 is readily compressible to prevent the spring from forcing the cam and sleeve 25 forwardly instead of being compressed to the cams action. v cam plate 29 does exert a slight longitudinal force on the cam 32 to aid in moving the sleeve 25 longitudinally on the shaft I5. Figure 3 shows that a number of plies of rubber stock 40 are wound, or otherwise placed upon a collapsible drum, or form, 4I prior to placing the reenforcing cord 38 thereon.

The fan bel'ts are then completed by superimposing at least one ply of fan belt stock upon the reenforcing cords. A feature of the invention resides in the belt stock used for it comprises rubber having countless small fibers 43 embedded therein, the fibers extending transversely of the .drum 4I. This stock is readily obtained since in milling,l or calendering rubberfiber mixtures, the fibers all are positioned inthe direction of passage of the mixture through the mill. Then the milled sheet produced is However, the

enforcing cords, as desired. Cam means are cut transversely and the strip obtained is positioned on the drum with the fibers 43 running across the drum parallel to the axis thereof.

To cut individual V shaped, in section, fan belts from the cylinder of material prepared on the drum 4I, a V shaped piece of rubber 42 must be cut from the cylinder between the sets of reenforcing cords, as shown, Next the drum 4I may be collapsed and the fan belts telescoped from engagement therewith. Obviouslythe re enforcing cord connecting adjacent sets of cords will be out when the V shaped rubber pieces 42 are formed and the exposed ends 39 of this cord (Fig. 4) should be out o or forced int the sides of the fan belt prior to vulcanization so that the finished fan belt has the cords entirely embedded. Cutting the fan belt from the drum 4I will expose the ends of a large number of the transversely extending fibers 43 in the fan belt stock. These ends are highly resistant to wear so that the cross-section of the fan belt is not appreciably reduced with extended use.' Thus Vthe fan belt retains the same radial position on the V shaped pulley seat in which it usually l's received whereby the belt does not rapidly wear loose after being initially made taut. The fibers extending transversely of the belt make it quite resistant to sidewise bending and transverse compression, but do not stiien the belt to circumferential bending, which is an essential property of the belt. The reenforcing cord is stretched prior to being wound upon the drum 4I so that it maintains the circumference of the fan belt constant. The resistance to transverse compression obviates the tendency for the belt to be squeezed to a narrower width as it passes over a V pulley, and thus avoids undesirable apparent lengthening or stretching in a circumferential varied by changing the relationship of the cam plate and cam. and by varying the relative rotation of the shafts II and I5 and, preferably, the number of notches in the cams. The spacing between the sets of cords can also be controlled in this manner and by the pitch of the threads out on the shaft I I'.

Figure 4 shows a fan belt when it is completely assembled and indicates how a set of seven cords are deposited immediately adjacent and then a space is skipped prior to depositing the second group of cords.

An overrunning clutch 45 is connected in the shaft I5 to prevent it from rotating when the shaft I3 and bracket 26 are returned to their starting positions by reversing the rotation of the shaft II.

Sometimes it may be desirable to cut the reenforcing cord extending between the sets of convolutions before the cord is covered with rubber.A

Then the ends of the reenforcing .cord would be secured immediately adjacent, or contacting, the sets of oonvolutions before covering the reenforcing cords with the next ply. In all events, the invention provides apparatus by which reenforcing cords can be deposited in fan belt stock in sucha manner that fan belts having reenforcing cords entirely embedded therein can be produced. y

In accordance with the patent statutes, I have illustrated and described the structure and method of constructing an embodiment of the invention. However, it will begunderstood that various modifications can be made Without departing vfrom the scope of the invention as defined in enforcing cords, separating the bands to expose the appended claims.

I claim:

1. In a process for manufacturing belts, the steps of placing a layer of belt stock upon a collapsible drum, winding spaced sets of adjacent convolutions of a continuous reenforcing cord upon the surface. of the belt stock, superimposing belt stockupon the reenforcing cords, cutting the built up belt stock into a plurality of annular bands at the portion of the belt stock between the sets of convolutions of reenforcing cords, and inserting the exposed portions of the reenforcing cords into the sides of the annular bands whereby a belt having reenforcing cords y totally embedded therein can be made.

2.*In a process for manufacturing belts, the steps of placing a layer of belt stock upon a collapsible drum, winding spaced sets of adjacent convolutions of a continuous reenforcing cord upon the surface of the belt stock. superimposing belt stock upon thefreenforcing cords, thereafter cutting the built up belt stock into a plurality of annular bands at the portion of the belt stock between the sets of convolutions of rea portion of the cord originally'extending between t-he sets of convolutions-thereof and cutting off the vexposed portions of the reenforcing cords whereby a belt having reenforcing cords totally embedded therein can be made.

3. In a process for simultaneously manufactui ing a plurality of reenforced belts upon a coilapsible smooth surfaced drum, the steps of applying a sheet of belt material to the drum, winding spaced sets of adjacent convolutions of a continuous reenforcing cord upon the drum, cutting the reenforclng cord connecting the sets of convolutions, securing the ends'of the reenforcing cord immediately adjacent the sets of convolutions thereof to form a circumferential space which has no cords thereon. covering the sets of convolutions of reinforcing cord with a rubber sheet to form a laminated cylinder of belt material, and cutting the cylinder into individual bands at the portion thereof between the sets of reinforcing cords whereby a belt having reenforcing cords totally embedded therein can 'be produced.

WILLIAM E. HAGGAN.

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