US2966337A - Reaction propelled bulb for drawing lines through conduits - Google Patents

Description

2,966,337 FOR DRAWING DU Dec. 27, 1960 R. s. KNAPP REACTION PROPELLED BULB LINES THROUGH CON ITS Filed June 16, 1958 INVENTOR. e5. 5 62a,;

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United States Patent REACTION PROPELLED BULB FOR DRAWING LINES OUGH CONDUITS Robert S. Knapp, St. Louis, Mo., assignor to Knapp- Monarch Company, St. Louis, Mo., a corporation of Delaware Filed June 16, 1958, Ser. No. 742,337

3 Claims. (Cl. 254-1343) This invention relates to a jet line bulb cap, particularly designed for low cost of manufacture and elficiency of operation in the control of a jet line attached to a Sparklet bulb when such bulb is used in a jet line gun of the type shown in Hensley et al., Patent 2,930,584.

A jet line gun is one which is directed into an electrical conduit or the like and punctures a Sparklet bulb to which a jet line of nylon or the like is secured, whereupon the bulb is jet-propelled from the gun and through the conduit, around any bends or curves therein, and finally exits from the opposite end of the conduit, having carried the line with it from a container of line so mounted as to permit paying out of the line therefrom. The nylon line then enables fish wires, electric wires and the like to be placed within the conduit. Before my invention, the jet line was kept from slipping olf the neck of the bulb by means of a special metal ring which was pressed on, or otherwise secured to, the bulb after the bulb was filled with CO or other gas under pressure and a cap welded on it.

One object of my invention is to eliminate the special ring and the operation required for assembling it to the bulb, and I provide a bulb cap larger in diameter than the bulb neck so that when the cap is welded in position it will serve as an enlargement to prevent the line from slipping off the neck of the bulb without the necessity of further manufacturing operations on the bulb.

Another object is to provide a special bulb cap preferably of the type shown in the Kochner Patent No. 2,685,383 of August 3, 1954, wherein the cap is provided with a flange-like enlargement or retaining flange to serve the purpose of holding the line from slipping off the bulb neck.

-A further object is to provide the retaining flange of special shape (with one or more notches) to protect the jet line as the bulb passes around curves and corners in the electrical conduit, thus minimizing the possibility of severing the line by impact of the outer edge of the flange against the conduit with the line between the two.

Still a further object is to provide a plurality of such notches to minimize the circumferential extent of the retaining flange and insure that the jet line will seek one of the notches as the bulb rounds a curve or turns a corner in the conduit, thus preventing fraying and severance of the line.

With these and other objects in view, my invention consists in the construction, arrangement and combination of the various parts of my jet line bulb cap, whereby the objects above contemplated are attained, as hereinafter more fully set forth, pointed out in my claims and illustrated in detail on the accompanying drawing wherein:

Fig. 1 is a side elevation of a jet line gun of the type herein referred to, a portion thereof being broken away and a Sparklet bulb with my jet line bulb cap thereon shown in the gun ready for firing, a jet line being associated with the gun and the bulb in the manner they are normally used;

Fig. 2 is a sectional view through a straight section of a conduit showing the bulb being propelled therealong by jet action and carrying the line with it;

Fig. 3 is a similar sectional view of a curved section of conduit showing by dotted lines the bulb negotiating the curve and by solid lines the position it takes thereafter;

Fig. 4 is an enlarged bottom plan view of a jet line bulb cap embodying my invention;

Fig. 5 is a perspective view thereof;

Fig. 6 is a side elevation of the cap resting on the neck of a bulb preparatory to being welded, the bulb being shown partially in cross section; and

Fig. 7 is a similar view entirely in section as taken on the line 7-7 of Fig. 4 and showing the welding operation completed.

On the accompanying drawing I have used the reference character G to indicate in general a jet line gun, B a Sparklet bulb and C my cap therefor. The gun G has a barrel 10 to receive the bulb B and a piercing pin 12 for puncturing the same so as to release the gas therefrom and thus permit the bulb to be jet-propelled from the barrel 10 and through a conduit or the like 21. Suitable mechanism is provided for actuating the piercing pin 12 under control of a trigger 14 but forms no part of my present invention, being instead the subject matter of the above-mentioned copending applications.

The cap C may be of the same general type shown in the Kochner Patent No. 2,685,383, formed by cold heading" or cold forging as disclosed therein. It is illustrated as being cup-shaped having a relatively thin wall 18 adapted to be pierced by the piercing pin 12 when the bulb is introduced into the gun G and the piercing pin is operated by the trigger 14. The cup is further defined by an annular wall 20 which is relatively thick as shown in Fig. 7. The cap C is formed by a cold heading operation from wire stock of suitable size and the cold heading 0r forging dies form the relatively thick wall 20 as Well as the relatively thin wall 18. They also form a flange 22 around the walls 18 and 20 as illustrated and additionally form spacing projections 24 on the bottom of the flange 22 and 26 on the outside of the wall 20.

When the cap C is placed in the neck 28 of the bulb B as shown in Fig. 6, the projections 24 space the flange 22 from the upper end of the neck 28 as shown by the dimension 30. At the same time the projections 26 space the annular wall 18 from the interior of the neck 28 equally all the way around the wall and neck as shown by the dimension 31. Thus, the projections 24 and 26 cooperate to provide suitable passage for the charging gas from a pressure chamber as illustrated in said Kochner patent and also in Tomasek et al., Patent No. 2,481,042 which is directed to apparatus for charging these bulbs.

After the desired quantity of gas under pressure has been introduced into the bulb B, the gas is cut off and the cap C is welded by passing a welding current through the cap and bulb. This heats the contacting parts (upper end of neck 28 and lower surfaces of projections 24) so that they, under further pressure and movement toward each other, are welded together, the bottom of the flange 22 finally engaging the upper end of the neck 28 and the welding operation being completed between the lower surface of the flange and the neck 28 so that in effect the cap and bulb become integral as indicated by the cross sectioning in Fig. 7. During the welding operation the projections 26 serve the further purpose of keeping the cap C centered in relation to the neck of the bulb.

At a plurality of points (four as illustrated on drawings) the flange 22 is enlarged as indicated at 22a or, explained differently, I provide a flange of the diameter indicated by the projections 22a and notch it at four points, the notches being indicated 22b. The outer edges of these notches are preferably rounded. The total di ameter of the portions 22a is preferably intermediate the diameter of the neck 28 and the diameter of the bulb B indicated at c, a and b respectively in Fig. 2. Thus, the projections 22a serve as an effective means to prevent the jet line 18 tied at 20 to the neck 28 from coming olf the neck during the jet-propulsion of the bulb as in Fig. 2 wherein the issuing jet-of gas is indicated 32. One of the notches 22b will receive the line during the travel of the bulb through the conduit 22 because of the tension on the line produced by the necessity of unfurling it from the container 16.

When the bulb B enters a curve 21a of the conduit 21 as shown by dot-ted lines in Fig. 3, it of course follows the curve, and when it reaches the solid line position it is jerked away from the outside wall of the curve by the resistance of the line (solid line showing) at which time the flange of the cap might pinch the line between the flange and the wall of the conduit. With my cap C, however, the line seeks a notch 22b of the flange so as to extend therethrough instead of being frayed or cut by the peripheral edge of the flange.

From the foregoing specification it will be obvious that I have provided a bulb cap particularly designed for jet line operation, and my cap, in addition to serving as a cap for the bulb, serves as an enlargement to prevent the line from slipping off the neck of the bulb and at the same time as a guide means for the neck end of the bulb during its jet-propulsion along the conduit. The cap is of such character that the jet line is protected against fraying and cutting or severing by being pinched between the flange and the conduit. The rounding of the outer edges of the notches 22b facilitates entry of the line into a notch 22a of the cap during the jet-propulsion of the bulb through the conduit 21 and around curves 21a thereof. At the same time the type of cap disclosed eliminates the necessity of an additional part and an additional operation such as used prior to my invention, and thus reduces the cost of a jet bulb for jet line gun operation.

Some changes may be made in the construction and arrangement of the parts of my jet line bulb cap without departing from the real spirit and purpose of my invention and it is my intention to cover by my claims any modified forms of structure or use of mechanical equivalents which may reasonably be included within their scope.

I claim as my invention:

1. A compressed-gas-driven device adapted for drawing a line through conduits or the like, said device comprising, in combination: an elongated hollow bulb having a reduced neck at one end thereof; and a cap member welded to the terminus of the bulbs neck for sealing the bulb, said cap member having a disc-like portion which includes a relatively thin, puncturable, part that bounds the space enclosed within said bulb, and an annular flange part that lies in a plane normal to the longitudinal axis of the bulb and that extends radially outwardly of the neck of the bulb to serve, in part, as a bumper when the device is being projected through a conduit or the like, the portion of the flange part located outwardly of the neck of the bulb being notched axially to provide a plu rality of axially extending passageways through said flange part, and the outermost portions of said flange adjacent the notches being rounded to define rounded entrance corners at the entrances to said notches.

2. A compressed-gas-driven device adapted for drawing a line through conduits or the like, said device comprising, in combination: an elongated hollow bulb having a reduced neck at one end thereof; a cap member welded to the terminus of the bulbs neck for sealing the bulb, said cap member having a disc-like portion which includes a relatively thin, puncturable, part that bounds the space enclosed within said bulb, and an annular flange part that lies in a plane normal to the longitudinal axis of the bulb and that extends radially outwardly of the neck of the bulb to serve, in part, as a bumper when the device is being projected through a conduit or the like, the portion of the flange part located outwardly of the neck of the bulb being notched axially to provide a plurality of axially extending passageways through said flange part; and an elongated line secured at one end thereof to said bulb and extending through one of said axial notches in the flange part of the cap member, to trail from the bulb as the bulb is driven through a conduit or the like.

3. A compressed-gas-driven device for drawing a line through conduits or the like, said device comprising, in combination: a compressed-gas-containing bulb having a reduced neck at one end of the bulb and a puncturable cap member connected to the neck to seal the bulb, a line secured to the bulb, and bumper means to protect the line from fraying and severance, as the bulb is reactionpropelled through a conduit or the like by escape of the compressed gas from within the bulb after said cap member is punctured, said bumper means including a disc-like flange means connected to the neck on said bulb, said flange means being of greater diameter than the diameter of said neck, the outer periphery of said flange means serving as a bumper and having a plurality of axially extending notches therein to permit passage of said line, from the point of securance of the line to said bulb, rearwardly through one of said notches.

References Cited in the file of this patent UNITED STATES PATENTS 1,692,710 Spahn Nov. 20, 1928 1,702,532 Boomer Feb. 19, 1929 2,425,448 Weida Aug. 12, 1947 2,546,566 Schweizer Mar. 27, 1951 2,685,383 Kochner Aug' 3, 1954

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