US2579468A - Apparatus for making coaxial cable units - Google Patents

Description

Dec. 25, 1951 s. E. BRILLHART 2,579,463

APPARATUS FOR MAKING COAXIAL CABLE UNITS Filed Oct. 10, 1946 4 Sheets-Sheet 1 FIG.

INVENTOR 8.5. BR/ LHART I A T TORNEY Dec- 5-, 1951 s. E. BRILLHART APPARATUS FOR MAKING COAXIAL CABLE UNITS 4 Sheets-Sheet 3 Filed Oct. 10, 1946 INVENRDR S. E. BR/L L HAR 7' A T TORNE V Dec. 25, 1951 Filed Oct. 10, 1946 s. E. BRILLHART 7 2,579,468

APPARATUS FOR MAKING COAXIAL CABLE UNITS 4 Sheets-Shet 4 wvavron 5,5. BR/LLHART ATTORNEY Patented Dec. 25, 1951 APPARATUS roa MAKING COAXIAL cum UNITS Samuel E. Brillhart, Lutherville, Md., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application October 10, 1946, Serial No. 702,491

3 Claims.

This invention relates to apparatus for making coaxial cable units.

I l rsometypes of apparatus for forming coaxial cable units, soft, plastic washer-like insulating discs are positioned upon a central conductor. The soft, plastic insulating discs are fed through guide. chutes from hoppers to transfer devices. a .fter which the transfer devices move the discs intooriented positions in notches formed in applicator wheels. The applicator wheels advance the discs over knives, which slit the discs radially, and then over guides which enter the slits in the discs and keep them open. The wheels move the discs from the guides onto the central conductors with a wiping action. I

With apparatus heretofore known, it has been diflicult to handle the soft, plastic discs without jamming, the discs, which jamming requires stopping the whole apparatus for forming coaxial cable units with which the disc feeding, slitting and applying devices are associated. Furthermore, the discs sometimes become displaced from their oriented positions in the notches in the applicator wheels so that, as the .displaced discs are moved over the knives, the knives form non radial slits therein. This prevents proper application of the discs onto the central conductors. In addition, the discs sometimes were agitated so much that they acquired static charges, which prevented the discs from feeding freely through the guide chutes.

An object of the invention is to provide new and improved apparatus for making coaxial cable units.

A further object of the invention is to provide new and improved apparatus for feeding insulating discs from hoppers to oriented positions in notches in applicator wheels without jamming and without the discs developing static charges, and for maintaining the oriented positions of the discs as the applicator wheels move the discs over slitting knives so that the knives slit the discs properly.

An apparatus illustrative of the invention includes a straight guide chute disposed vertically for-feeding by gravity insulating discs from a hopper feed including a slow-moving, non-static forming vane to a transfer device. The transfer device feeds the discs into notches in a rotating applicator wheel, and a guide maintains the discs in such positions as the applicator wheel moves them over a slitting knife that the knife slits the discs radially.

A complete understanding of the invention may be obtained from the following detailed description of an apparatus forming a specific embodiment thereof, when read in conjunction with the appended drawings, in which: i

Fig. 1 is a fragmentary, vertical section of an apparatus forming one embodiment of the invention;

Fig. 2 is an enlarged, fragmentary, vertical section taken along line 2-2 of Fig. 1;

Fig. 3 is an enlarged, substantially vertical section taken along line 8-3 of Fig. 2;

Fig. 4 is an enlarged, fragmentary section taken along line 4-4 of Fig. 2:

Fig. 5 is an enlarged, fragmentary section taken along line 5-5 of Fig. 2;

Fig. 6 is an enlarged, fragmentary, vertical section taken along line 6-6 of Fig. 1;

Fig. 7 is an enlarged, fragmentary, horizontal section taken along line ll of Fig. 1;

Fig. 8 is an enlarged, fragmentary, vertical section taken along line 6-6 of Fig. 1;

Fig. 9 is a fragmentary, vertical section taken along line 9-9 of Fig. 6;

Fig. 10 is an enlarged perspective view of a portion of the apparatus;

Fig. 11 is an enlarged, substantially vertical section taken along line ll-ll of Fig. 1, and

Fig. 12 is an enlarged, substantially vertical section taken along line l2-i2 of Fig. 1.

Referring now in detail to the drawings, there is shown in Fig. 1 an apparatus for feeding applying soft, plastic, washer-like, insulating discs Ill-l0, which may be composed of polymerized ethylene, for example, to a conductor II to form a core unit of a coaxial cable. The discs I6--ill are fed in edge-to-edge positions to straight, vertical guide chutes l2 and I4 by a hopper feed l5, certain features of which are disclosed and claimed in copending application Serial No. 702,493, filed October 10, 1946 by A. C. Frankwich now Patent No. 2,579,486 issued December 25, 1951. The discs ill-Ill are propelled by gravity down the vertically disposed guide chutes i2 and I4, and the discs in the guide chute M are fed into notches l6l6 formed in an applicator wheel H by a plunger IS, the height of which is less than the diameter of the discs Iii-i0. The chute It extends to the level of the top of the applicator wheel I1, and is almost centered with respect to the applicator wheel H but is slightly to the right of the center, as viewed in Fig. l. The chute I2 is just slightly to the left of the center of the applicator wheel IT.

The plunger i8 is urged to the right, as viewed in Fig. 6, by a compression spring 20, but is prevented by a cam 2 I carried by the applicator wheel H from moving to the right except when one of the notches l6-l 6 is in a position to receive one of the discs, and the cam engages a cam follower 22 carried by the plunger. The discs ll-ll fed to the applicator wheel ll pass through a notch 26 formed in a'U-shaped guide 26, which holds the discs centered in the notches l6-I6 while the applicator wheel I! moves the discs over a knife 33 (Fig. l), which forms line-like, radial slits in the discs. A thin arcuate guide 3| extends from the knife 36 to an end 32 of a wedge-shaped expander 34 (Figs. 10, 11 and 12) and forms a continuation of the arcuate guide 3| (Fig. l). The expander 34 extends to the point at which the guide 3| wipes the discs onto the conductor H. The thin arcuate guide 3| enters the radial slits formedin the discs and holds the discs in oriented positions as the applicator wheel ll rotates in a clockwise direction, as viewed in Fig. 1, and also holds the slits in the discs slightly open. The expander 34 tapers gradually from an end 32 of the guide 3| abutting the end to a thicker end 35, which is near the point of application of'the As the discs are carried along the expander, the expander gradually opens the slits in the discs sufliciently that only the inner ends of the walls of the slits contact the conductor I! as the discs are wiped onto the conductor. The gradual expansion of the slits in the discs by the expander 34 prevents crushing of the soft, plastic discs, which might occur if the discs were wiped onto the conductor with the slits not previously expanded sufflciently. The fact that the walls of the slits are held by the expander out of contact with the conductor H except for the innermost portions of these walls prevents contamination of and formation of conductive paths along the walls of the slits from contact with the conductor.

On each movement of the plunger II to the right, as viewed in Fig. 6, the plunger l6 moves one ofthe discs IO-lll into one of the notches 16-" which is in a disc-receiving position, and in so doing moves the lowermost one of the discs l6-l3 in the guide chute l4 out, from imder the remainder of the discs in the guide chute l4. The remainder of the discs then drop upon a relieved portion 32 of the plunger l3 while the plunger is at its farthermost position to the right. As the plunger is moved back to the left from this position by the cam 2 I, a jiggling finger 33 projecting above the relieved portion 32 of the plunger moves the column of discs Ill-I in the guide chute l4 upwardly to dislodge any of the discs which might possibly stick in the guide chute M.

The movement of the plunger l3 to the left continues until the finger 33 moves out completely from under the column of discs in the guide chute l4, and the column of discs then drops to the bottom of the guide chute l4. The total height of the plunger l6 and the finger 33 is slightly over half of the diameter of one of the discs ill-l6 so that the plunger engages the discs Ill-l6 at the centerline of the discs and does not slide under the discs asit is moved toward the right, as viewed in Fig. 6. However, in the operation of the plunger l6, the discs in the guide chute l4 drop somewhat over half the diameter of one of the discs as the plunger 18 is moved to its farthermost right height is substantially less than the diameter of one of the discs.

The dropping of the discs in the guide chf te l4 through the distance of the diameter of one of the discs in two almost equal steps during each reciprocation of the plunger insures that there is sufficient time for the lowermost one of these discs to reach the bottom of the guide chute I4 before the movement of the plunger II to the right begins, even at very high operating speeds of the plunger 13. The jiggling finger 33 agitates the column of discs in the guide chute H at each stroke to prevent sticking of the discs in the guide chute and thereby insures continuous feed of the discs down the guide chute.

The discs Ill-l3 are fed down the guide chute l2 and are fed into notches 36-36 in an applicator wheel 31 positioned directly below the applicator wheel II by means of elements similar to the plunger II, the cam 2| and their associated elements. These elements include a plunger 33 (Figs. 7 and 8), which is mounted on a guide pin 33 urged to the right, as viewed in Fig. 8, by a compression spring 46 tohold a cam follower 4! against a cam 42 carried by the applicator wheel 31. The cam 42 is identical with the cam H except that the contour of one of these cams is right hand while that of the other is left hand. The cam 42 is provided with a series of gently sloping plunger-retracting portions 43-43 extending fromdwell portions 44-44 to sharply relieved vertical drop plunger-feeding portions 46-45. The plunger-retracting portions 43-43 push the plunger 33 slowly back to the left after each feeding stroke, and the plunger-feeding portions permit the compression spring 46 to make almost instantaneous the feed of the plunger?" to the right to feed a disc into one oi the notches 36-36 in the rotating applicator wheel.

A pivotally mounted brake shoe 41 (Fig. 7) having a deflecting portion 43 is urged by a spring-pressed plunger 43 against the disc which is the disc to be fed next into one of the notches 36-36 in the applicator wheel 31. The

0 brake shoe prevents that disc from-movement to receive the disc. Hence, jamming of the disc with the applicator wheel from premature move- .ment of the disc is prevented.

A knife 66 (Fig. 1) slits the discs l'6-l6 radially, and a thin arcua'te guide 5| extends to an expander 64, which extends substantially to the point of application of the discs to the central conductor II, and is identical in construction and operation with the expander 34. The expanders 34 and 64 and the elements associated therewith are disclosed and claimed in copending application Serial No. 702,494, filed October 10, 1946 by A. C. Frankwich.

The wheel 31 rotates in a counterclockwise direction, as viewed in Fig. 1, to wipe the discs Il-Il upon the conductor ll alternately with respect to the discs applied by the applicator wheel II to the conductor. A U-shaped guide 56 holdsthe discs in the notches 36-36 centered in the notches as each disc is moved over the knife 56 so that the knife forms radial slits in the discs. The combined length of the guide 3| and the expander 34 is substantially the same as that of the guide 6| and the expander 64 so that the discs receive the same treatment as they are moved along the guides and the expanders. That is, each of the discs is rubbed to the same extent and for the same length of time by the guides SI and SI and is expanded to the same extent and for the same length of time by the expander- s 36 and 54. Hence, all the discs I haveridentical mechanical and electrical properties. Thus, except for the greater travel of the discs in the guide chute I2 as compared to the discs in the guide chute I4, the discs applied by the applicator wheel I! are subjected to the same conditions, from entrance into the hopper to application to the conductor, as the discs applied by the applicator wheel 31. In the guide chutes l2 and H, the discs are freely floating, and the.chutes protect the discs against contamination. Hence, the difference in the length of the guide chutes has no effect on the uniformity of treatment of the discs, and does not affect the properties of the discs.

The hopper feed I5 includes a sloping-wall hopper 60 having an opening 6| (Fig. 2) for placing the insulating discs II|I haphazardly into the hopper, and also includes a side wall 62 provided with a vertical slot 63 therein. The hopper isalso provided with a bottom 810065. A vane I0 is keyed to a shaft II whose axis is located slightly to the right of and below the side wall 62 of the hopper 60, as viewed in Fig. 2. The shaft II is rotatably mounted in bearings IL-H. 1), and is oscillated slowly by an arm 15 connected by a link I6 to a suitable crank (not shown). The shaft 'II slowly oscillates the vane I0 between a position in which the vane is shown in full lines in Fig. 2, which position is its lowermost position, and a position in which the vane is shown in broken lines, which position is its uppermost position.

When the vane is in its lowermost position, the discs I0I0 in the hopper 60 fall edgewise into grooves 00 and 8| extending along an upper edge 02 of an arcuate blade portion 03 thereof. The grooves 80 and 8| are provided with flared entrange portions 06 and 81 (Fig. to facilitate entrance of the discs therein. When the vane I0 is in its lowermost position, the grooves 80 and 0| tilt downwardly to the right, as viewed in Fig. 2, but the discs in these grooves are prevented from sliding out of the grooves by stops, of which a stop 85 is shown, positioned at the right ends of the grooves. The grooves 80 and BI are sufllciently long that the hopper feed I5 maintains the chutes filled with the discs even though its speed is slow.

Discs made of a plastic, such as polyethylene or the like, tend to acquire static charges when agitated or rubbed against other objects, particularly when certain atmospheric conditions prevail. The slow speed of the vane, plus the absence of any mechanical agitator for the hopper feed, keeps at a minimum the agitation of the discs in the hopper so that electrostatic charging of the discs, which results from agitation, is held to a minimum.

As the vane I0 is swung to its uppermost position, the discs I0I0 slide downwardly to the left in the grooves 80 and 8|, and pass through passages 90 and 9| formed in the vane 10. The entrance portions of the passages 90 and 9| are straight and are aligned with their respective grooves 00 and 8|, and the remainder of the passages 90 and 9| are arcuate with the axis of the shaft II at the center thereof. The passages 90 and 9| are aligned with and run into arcuate grooves I00 and IM (Fig. 4), which have the axis of the shaft II as their centers.

A portion I02 of the periphery of the vane 10 is coextensive with the grooves I00 and Ill and is concentric with these grooves. The depth of the grooves I00 and "I is substantially equal to but slightly larger than the diameter of the discs Iii-I0. Tangential deflecting portions, of which a tangential deflecting portion I05 of the guide chute I4 is shown, rest upon the bottoms of the grooves I00 and IN, and deflect the discs II? out of the grooves I00 and I 0| into the guide chutes I2 and II. The right hand edge, as viewed in Fig. 2,- of the guide chute I2 is substantially tangential to the bottom of the groove I00.

A raised guard portion 0 of the vane 10 extends arcuately from the upper edge 02 of the blade portion 03 of the vane concentrically with the passages 90 and 9| and terminates at the right ends of the grooves I00 and IN. The pe riphery of the guard portion H0 is spaced substantially outwardly from the outer periphery of the passages 90 and 9|, and also fits closely in the slot 63 in the side wall 62 so that the guard portion serves to close the slot. The length of the guard portion H0 is such that the guard portion blocks the slot 63 throughout the path of movement of the vane I0 in its oscillation, thereby preventing escape of the discs from the hopper but is short enough that the guard portion does not strike the chutes I2 or I4 when the vane 10 is oscillated to its broken line position, as shown inFig. 2.

The height of the guard portion H0 is such that when the vane I0 is in its uppermost position, the blade portion 83 of the vane is spaced a substantial distance from the side wall 02 of the hopper 60, which distance is sufilcient to prevent jamming of the discs between the wall 02 and the edge 82 of the blade portion. Also, the blade portion 83 is provided with a relieved portion III at the end thereof adjacent to the guard IIO, which increases the clearance between the side wall 62 and the outer edge 82 of the blade portion when the vane is in its uppermost position. However, the depth of the grooves 80 and 8| coextensive with the relieved portion III is equal to the diameter of the discs I0--I|I, and the flared entrance portions 96 and 81 are not present in these portions of the grooves so that the discs in the hopper do tend to enter these portions of the grooves directly from the hopper.

The guard H0 is provided with slots I20 and I2I extending from the periphery thereof to the passages and 9|. The width of each of the slots I20 and I2I is not enough to permit the discs to enter the slots I20 and III. Arcuate guides I30 and |3I are designed to project into the slots I20 and I2I, respectively, and to prevent the discs from leaving the grooves I00 and II in the vane I0 when the vane is in its lowermost position, thereby preventing jamming of the discs. The guides I30 and |3| serve to guide the discs into the guide chutes I2 and I4, respectively.

The discs are fed by gravity down the straight, vertical guide chutes I2 and Il (Fig. 1). Since the guide chutes have no curves therein and the interior surfaces are smooth, there is no possibility of the discs becoming stuck in the chutes. Also, the plungers I0 and 30 intermittently jiggle the columns of the discs to prevent sticking of the discs in the chutes. Since the chutes are straight and vertical, compressed air or mechanical disc-advancers for the chutes are eliminated in feeding the discs, so that dirt and moisture concomitant with compressed air and abrasion and jamming of the discs by mechanical 7 advancers are avoided. Also, the slow moving pick-up arrangement in the hopper avoids the formation of static charges on the discs fed to the chutes, and the discs have no tendency to cling to the walls of the chutes as they sometimes do when carrying static charges.

In the operation of the apparatus described hereinabove, the discs Ill-l are fed by the hopper feed into the straight, vertical guide chutes l2 and I4. The discs in the guide chute l4 are fed by gravity to the bottom thereof, which is offset from the applicator wheel ll. Each of the discs in the guide chute I4 is pushed seriatim from the guide chute l4 by the plunger i8 (Fig. 6) into the U-shaped guide 26 and one as rases of the notches I6--l6 in the applicator wheel l1.

The wheel moves the discs facewise past the knife 30 (Fig. 1) to slit the discs and the guide 26 centers the discs with respect to the knife 30 so that the slits are formed radially therein. The applicator wheel l1 moves the discs along the arcuate guide 3|, over the wedge-shaped expander 34, and wipes them onto the conductor II at uniformly spaced points thereon as it is advanced tangentially between the applicator wheels 11 and 31. The wedge-shaped expander 34 gradually expands the slits to prevent'damage to the soft discs from abrupt expansion thereof and protects the walls of the slits in the discs from contamination.

The discs in the chute I4 are fed by gravity therethrough down across the faces of the applicator, wheels H and 31 to a point offset from the notched periphery of the applicator wheel 31. The discs are pushed by the plunger 38 one at a time from the bottom of the chute H toward the applicator wheel 31 and into the notches 36-36 in the applicator wheel 31. The plunger 38 jiggles the discs in the column to prevent sticking thereof, and the brake shoe 4'I prevents the discs from moving'into contact with the applicator wheel 31 prior to the time when one of the notches 36-36 is in a disc-receiving position, when the plunger 38 pushes the foremost disc past the brake shoe into that notch.

The U-shaped guide 56 holds the discs l0l0 centered with respect to the knife 50 as the applicator wheel 31 moves them past the knife. As this occurs, the lmife forms radial slits in the discs to permit the discs to be wiped onto the conductor II. The discs then are moved over the thin guide 5| (Fig; 1), which enters the slits therein, holds the discs slightly open and in properly oriented positions for application to the conductor II. The wedge-shaped expander 54 expands the slits in the discs to facilitate applying the discs to the conductor II and to prevent damaging and contaminating the discs. The applicator wheel 31 wipes the discs carried thereby onto the conductor at points thereon spaced equally between the discs applied by the applicator wheel l1.

The above-described apparatus orients, feeds, slits and applies the insulating discs Ill-l0 to the conductor ll without jamming, abrading, contaminating, wetting or electrostatically charging the discs so that the apparatus is not stopped from jamming and neither the physical nor electrical properties of the discs are impaired by such operations. The above-described apparatus has a minimum of movable parts so that it is simple in its construction and operation, while it is highly effective in continuously feeding, slitting and applying discs.

The elements of the above-described apparatus are simple in construction so that they may be made with mass production techniques, which effects substantial economies in the manufacture and maintenance of the apparatus. The slow movement of the vane 10 keeps the chutes I! and I4 filled, but keeps static charges on the discs Ill-Ill at a minimum. Furthermore, the treatment of the discs applied by the applicator wheel I! is substantially identical with that of the discs applied by the applicator wheel 31 from entrance in the hopper to application to the conductors so that the discs have uniform mechanidirection for applying insulating discs to a hori- V zontal conductor advanced tangentially along the lower periphery of the wheel, a second wheel having a plurality of disc-receiving notches extending radially inwardly from the periphery thereof mounted in said vertical plane directly below the first applicator wheel for rotation in a direc-- tion opposite to that of the first applicator wheel I for applying insulating discs to the conductor, a straight guide chute extending vertically from an elevated hopper feed to a point at the same level as but offset from the top of the first applicator wheel and in a plane perpendicular to that wheel for feeding discs edgewise and by gravity in a straight column from the hopper feed to said point, a plunger reciprocable parallel to the axis of the first applicator wheel for pushing the discs edgewise from the guide chute into the notches in the first applicator wheel, a second straight guide chute extending vertically from the hopper feed to a point at the same level as but offset from the bottom of the second applicator wheel and in a plane perpendicular to that wheel for feeding discs edgewise and by gravity in a straight column from the hopper feed to the last-mentioned point, a second plunger reciprocable parallel to the axis of the second applicator wheel for pushing discs edgewise from the second guide chute into the notches in the second applicator wheel, and means for alternately and intermittently reciprocating the plungers to feed discs into the notches on the rotating applicator wheels, each of said plungers having an upwardly protruding finger on the tip end thereof so that the columns of discs will be jiggled during each reciprocation of the plungers to prevent Jamming of the discs in the guide chutes.

2. In an apparatus for feeding insulating 'discs from an elevated hopper into spaced radial notches on the periphery of a vertical rotating applicator wheel from which the discs may be applied to an advancing horizontal conductor of a coaxial cable, the improvement which comprises an entirely straight guide chute extending vertically from the hopper to a point horizontally offset from the periphery of the vertical applicator wheel in a plane substantially perpendicular to the axis of the wheel for feeding discs edgewise and by gravity in a straight column from the hopper to said point, a horizontal guideway extending from the bottom of the chute 'to the periphery of the wheel for guiding discs from the chute into thenotches on that periphery, a plunger reciprocable along the guideway for pushing a disc edgewise from the guide chute into a notch on the periphery of the wheel, said plunger having on the tip end thereof a finger protruding upwardly a distance "above the guideway of slightly more than half the diameter of a disc to be pushed so that the disc will be positively engaged and so that the column of discs will be jiggled during each reciprocation of the plunger to prevent jamming of the discs in the guide chute, and means for intermittently reciprocating the plunger in timed relation to the spacing of the notches on the rotating applicator wheel.

3. In an apparatus for feeding insulating discs from an elevated hopper into spaced radial notches .on the periphery of a vertical rotating applicator wheel from which the discs may be ---applied*-to"an'advancing horizontal conductor of a coaxial cable, the improvement which comprises an entirely straight guide chute extending vertically from the hopper to a point horizontally offset from the periphery of the vertical applicator wheel in a plane substantially perpendicular to the" axis of the wheel for feeding discs edgewise and by gravity in a straight column from the hopper to said point, a horizontal guideway extending from the bottom of the chute to the periphery of the wheel for guiding discs from the chute into the notches on that periphery. a plunger reciprocable along the guideway for pushing a disc edgewise from the guide chute into a notch on the periphery of the wheel, said plunger having on the tip end thereof a finger protruding upwardly a distance above the guideway of slightly more than half the diameter of a disc to be pushed so that the disc will be positively engaged and having a relieved portion so that this portion of the plunger protrudes upwardly a distance above the guideway of slightly less than half the diameter of.a disc, whereby the column of discs will be jiggled twice during each reciprocation of the plunger and the column will fall a distance equal to the diameter of a disc in two nearly equal steps to prevent jamming of the discs in the guide chute, and means for intermittently reciprocating the plunger in timed relation .to the spacing of the notches on the rotating applicator wheel.

SAMUEL E. BRILL-HART.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 2,426,623 Larsen Sept. 2. 1947

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