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Publication numberUS3052279 A
Publication typeGrant
Publication dateSep 4, 1962
Filing dateMar 11, 1958
Priority dateMar 11, 1958
Publication numberUS 3052279 A, US 3052279A, US-A-3052279, US3052279 A, US3052279A
InventorsCollin Jay H, Garrett John C
Original AssigneeCollin
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Flaring tool
US 3052279 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)


2 Sheets-Sheet l ,4.. W $m mm 1/ 0 I11 I hm mm 2 mm MN m .Tiw W M. NW NW J. H. COLLIN ETAL FLARING TOOL Sept. 4, 1962 Filed March 11, 1958 p 4, 1962 J. H. COLLIN ETAI... 3,052,279

FLARING TOOL 2 Sheets-Sheet 2 Filed March 11, 1958 7 5 40 m QP S Q 7 C. I 4 w 5 m Q. a fig & a" 5 i a 0 i l ja W 0% 5 6 United fltates Patent @fiine 3,052,279 Patented Sept. 4, 1962 3,052,279 FLARING TOOL Jay H. Collin, Pasadena, and John C. Garrett, Arcadia, Califl; said Garrett assignor to said Collin Filed Mar. 11, 1958, Ser. No. 720,710 12 Claims. (Cl. 153-79) This invention relates to a flaring tool and more particularly to an improved universal tool of this type adapted for rigid mounting on a bench and having shaping components which can be readily substituted for one another to provide either single or double flared tube ends with greater speed and uniformity than is possible with prior flaring tools.

The tool here disclosed is related to that described in our co-pending application for United States Letters Patent Serial No. 672,226, filed July 16, 1957, for Flaring Tool (Docket 992). However, the present construction differs in that it incorporates important improvements and is more versatile than the earlier described tool.

There has been an unsatisfied need over a period of many years for a universal flaring tool by which either single or double flared pipe ends could be provided at the users option with minimum delay and inconvenience in changing from one type of flare to the other. One of the reasons why the need has gone unsatisfied is that the long-standing specifications for single flare dictate a flare angle of approximately 45 degrees whereas the specification for double flares is for a flare angle of 37 degrees, both taken relative to the pipe axis. Accordingly, the conical flarin g adapter used for the final flare is not usable in making a single flare. Another reason is that the flared surfaces of tube ends should be formed to a high degree of uniformity and accuracy if a satisfactory fluidtype seal is to be achieved. The provision for readily replaceable flaring adapters on the activating plunger of the flaring tool unavoidably means a certain degree of looseness between the parts required for ease of operation and for the substitution of adapter components and this has accounted for inaccuracies in the finished product not tolerable in a commerically acceptable tool. Still another factor has been the need for a pipe clamping device having the particular angle of flare desired in the finished product depending on whether a single or double flare is required.

Accordingly, it is the purpose of this invention to pro vide an improved flaring tool obviating the foregoing and other shortcomings and disadvantages of prior flaring tools featuring a plunger so constructed and arranged that any one of a plurality of flaring adapters can be substituted for one another without need for fastener devices and precisely centered automatically as an incident of the flaring operation. To this end the flaring plunger is fitted with a permanent magnet for releasably and floatingly supporting the flaring adapters, each of the latter being provided with a flat base of magnetic material and being readily slidable transversely of the plunger end during assembly and disassembly as well as during the automatic centering operation.

Another important feature of the invention is the provision of improved pipe clamping means having holes of a range of sizes suitable for fitting diflerent diameter pipes and having the opposite ends of the pipe clamping openings differently flared as appropriate for forming single and double flared pipe ends.

Accordingly, it is a primary object of the invention to provide a universal flaring tool suitable for forming high precision single or double flares at the users option.

Another object of the invention is the provision of a flaring tool selectively usable to form either single or double flares and featuring an automatically self-centering flaring adapter.

Another object of the invention is the provision of a flaring tool having a pipe clamping device the openings of which are appropriately flared on one side for forming single flares and appropriately flared on the opposite side thereof for forming double flares.

Another object of the invention is the provision of a flaring tool having a flaring plunger provided with interchangeable flaring adapters some of which are suitable for making double flares and others of which are suitable for making single flares.

Another object of the invention is the provision of an improved flaring tool having a flaring plunger with readily replaceable adapters designed to be detachably held in place thereon by permanent magnet means.

These and other more specific objects will appear upon reading the following specification and claims and upon considering in connection therewith the attached drawings to which they relate.

Referring now to the drawings in which a preferred embodiment of the invention is illustrated.

FIGURE 1 is a side view of a flaring tool according to the present invention, parts being broken away and shown in section along a central longitudinal plane;

FIGURE 2 is a transverse sectional view taken along line 2-2 on FIGURE 1;

FIGURE 3 is a front end elevational view of the tool with portions of the device broken away;

FIGURE 4 is a transverse sectional view taken along the longitudinal center line of the flaring plunger and showing the plunger depressed to form a single flare;

FIGURE 5 is a fragmentary detail view in section showing the adapter used in forming the first step of a double flared tube end; and

FIGURE 6 is a view similar to FIGURE 5 showing the adapter employed in the second step of the double flare.

Referring to the drawings and more particularly to FIGURES 1, 2 and 3, there is shown a universal flaring tool designated generally 10 having a cast metal main frame 11. This main frame includes a generally flat base 12 having fixed to the center portion thereof a heavy duty upright 13 supporting the operating lever and a flaring plunger to be described presently. The rear corners of base 12 may be provided with vertical bores 15 for receiving bolts, screws or the like for rigidly mounting the flaring tool on a work bench. Additionally, the lateral side edges of the base are preferably channeled as indicated at 16 in FIGURE 3 to the end that overhanging ledge 17 can be used to facilitate the clamping of the tool within the jaws of a bench vise. Base 12 is notched, as indicated at 18, inwardly from its forward edge and in general alignment with the flaring plunger to accommodate the pipe being flared, the end of the conduit to be flared extending upwardly through this opening and being clamped in an opening of a clamping device designated generally 29.

The upright 13 has the configuration shown in FIG- URES 1 and 3 and its base is held firmly anchored by means of cap screws 22, 23 in an upwardly opening shallow recess 21 in base 12. Extending longitudinally across the bottom of upright 13 is a rectangular passage or guideway 24 through which the pipe clamping device 24) is freely slidable. Guideway 24 opens at its forward end into a large notch 25 extending laterally across the front half of the upright and provides free working space for the lower end of the flaring plunger and for the substitution thereon of the different flaring adapters.

Referring particularly to FIGURES l, 3 and 4, it will be seen that flaring plunger 28 is reciprocally mounted in a vertical bore 29 near the forward edge of upright 13 with its flanged lower end 3% normally held seated against the lower end of bore 29 by a compression spring 31 encircling the upper end of the plunger. One end of this spring rests in a channel at the upper end of bore 23 and its other end bears against a removable split ring keeper 32 seated in a groove at the upper end of the plunger. An important feature of the plunger is the provision of permanent magnet means housed within a vertical bore 33 opening through the lower end of the plunger. This magnet means includes a non-magnetic sleeve 34 and a small permanent magnet 35 telescoped together and held assembled within bore 33 as by a set screw 36. Preferably the lower ends of sleeve 34 and magnet 35 are accurately finished to lie flush with the lower end of the plunger, and acts in cooperation with plunger 28, preferably formed of magnetic material, to hold any one of the several flaring adapters releasably and slidingly clutched to the plunger end. A typical one of the adapters comprises the conical adapter 37 the base of which preferably has the same diameter as flange 30 of the plunger to facilitate the accurate assembly of the adapter to the plunger. It is pointed out and emphasized that each of the flaring adapters can be shifted transversely of the plunger relatively easily since the movement is crosswise of the lines of flux rather than in a direction tending to lengthen these lines.

The means for depressing the plunger to flare a pipe end comprises a lever 40 provided at its outer end with a hand grip 41 and with a cam shaped end 42 at its other end, the latter being eccentrically pivoted between the vertical side walls 43 of upright 13 by a pivot pin 44 locked in place by set screw 45 (FIGURE 3). Cam 42 is so positioned that clockwise rotation of handle 40 brings the cam into contact with the rounded upper end 46 of plunger 28 to depress the plunger and the adapter 37 supported thereon into the end of a pipe clamped in device 20. Normally lever 40 is swung counterclockwise to the position shown in FIGURE 1 allowing spring 31 to hold the plunger retracted.

Flaring device 20 is best shown in FIGURE 2 and comprises a pair of elongated jaws 48, 48 having their rear ends pivotally interconnected as by a tie link 49 and pivot pins 50. A similar cross link 51 has one end rigidly secured to the front end of one of the jaw members 48 as by rivet 52. The opposite end of link 51 has a close sliding fit in a notch across the forward end of the other jaw member 48 and serves as a pilot assuring the accurate closing of the jaws toward one another when clamping to a pipe to be flared. The facing inner edges of the jaw members have oppositely facing mating semi-circular cutouts 54 of graduated diameters arranged along the jaws and each opening is formed with threads or the like teeth for gripping pipe. The constructional details of the clamping device thus far described are generally conventional whereas the features now to be mentioned are novel and form important features of the present invention. Reference is had to the flared annular surfaces 55 and 56, respectively, at the opposite ends of pipe clamping openings 54. The angle of flare of these surfaces differs in each instance, the surfaces 55 on one side of device 20 being suitable for forming single flare pipe ends while the angle of surfaces 56 at the opposite ends of the openings along the other side of the device are different and suitable for forming double flared pipe ends. Customarily single flare angles are at 45 degrees to the axis of the pipe whereas double flares customarily lie at 37 degrees to the pipe axis.

Another feature of the clamping device is the provision of positioning notches 58 transversely across the lateral sides of jaws 48 and accurately centered opposite pipe clamping bores 54 in such manner as to accurately position the clamping opening relative to the plunger for a given pipe flaring operation. It is pointed out that these positioning notches 58 are provided to the end 4 that the clamping device may be accurately positioned by these notches irrespective of which broad surface of the device is uppermost.

Cooperating with notches 58 in centering device 20 IS a spring pressed detent 59 having its rounded end projecting through the side wall of guideway 24 and urged outwardly thereinto by a compression spring 60. This spring is held in assembled position by a cap screw 61 (FIGURE 2). Slidably mounted in a transverse bore 62 on the other side of guideway 24 is a pin 63 normally urged to a retracted position by a compression spring 64 encircling its shank portion. A manually operated clamping lever 65 projects laterally from one side of the flaring tool and is pivotally connected thereto by a pivot pin 66. The cammed end 67 of lever 65 bears against the outer end of pin 63 in a manner to force it inwardly in opposition to spring 64 when pivoted counterclockwise as viewed in FIGURE 2 with the result that the pin engages the side of one jaw 48 and forces the device against the opposite side wall of passageway 24. This not only locks the clamping device against movement along the passageway but also forces the threads in the side walls of the openings 54 against the pipe. When the pipe and clamping device is so locked, the plunger operating lever may be pivoted in a direction to lower the plunger and flaring adapter into the end of the tube flaring it outwardly against the cooperating flared sur-. face 55.

In operation, let it be assumed that it is desired to provide the end of a pipe 69 with a single flare. To do so, clamping device 20 is pulled forwardly out of the slide way 24 so that its jaws can be opened about the rear pivot link 43. The pipe is then inserted in the appropriately sized one of openings 54 with the end to be flared projecting slightly above its upper surface. In inserting the pipe in the clamping device it is important that the surface thereof having the degree flaring surface be uppermost. The clamping device is then slid rearwardly along slideway 24 until the pipe is centered beneath plunger 28, this being determined by the seating of detent 59 in the associated one of positioning notches, 58. Clamping lever 59 is then pulled toward the operator to press pin 63 inwardly to lock the clamping jaws tightly closed and pressed against the far side of guideway 24.

A conical flaring adapter 37 having conical faces lying at 45 degrees to the axis of the plunger is then slid across the end of the plunger and generally centered thereon by aligning its base with the edge of plunger flange 30. The adapter may or may not be aligned with the tube but this is immaterial since the rotation of the flaring handle 40 towards the operator to depress the plunger brings the adapter into contact with the rim edge of the tube. If the adapter is not then accurately centered, the adapter is automatically shifted in the proper direction and amount to bring adapter 37 precisely into alignment with the tube axis. Further rotation of the operating handle forces the adapter into the tube end flaring it outwardly and into firm contact with flared surface 55 of the clamping device. The handle is then reversely rotated allowing the plunger to be retracted by spring 31. Clamping handle is rotated rearwardly releasing the clamping device so that it can be pulled outwardly and the flared tube removed.

Next, let it be assumed it is desired to provide a second tube 70 with a double flared end. It is first necessary to withdraw the clamping device 20 from slot 24 and to turn it over so that flared surfaces 56 of openings 54 are upperlmost. Tube 70 is then positioned in the appropriately sized one of openings 54 with its upper end spaced a somewhat greater distance above the device than was the case when forming a single flare. The clamping device is then reinserted in passageway 24 and clamped there by handle 65. Next, the operator slides conical adapter 37 across the end of plunger 28 and lays it to one side so that the double flaring adapter (FIGURE 5) can be held assembled on the end of plunger 28 by the permanent magnet 35.

Adapter 75 has a cylindrical main body 76 having a close sliding fit with the tube to be flared and a conical lower end 77. The opposite end of the cylindrical body 76 is integral with a circular head 78 having an angular groove 79 encircling the base of main body 76, the side wall of which groove flares at an angle of about 30 degrees. As is true with respect to the other adapters, adapter 75 is formed of magnetic material so that it may be magnetically held against the end of plunger 28.

When adapter 75 has been assembled to the plunger, the device is operated in the same manner described above to produce an outwardly-bulging double flared ring at the top of tube 70 having the shape shown in FIGURE 5. It will be understood that as the conical end 77 of the adapter is lowered into engagement with the rim edge of the tube it cooperates with the tube to shift the adapter in the amount and in the direction required to center the adapter precisely in the center of the pipe. Further lowering of the plunger shapes the pipe end as shown. After the plunger has been retracted, the flaring adapter 75 is removed and replaced with conical adapter 37 (FIGURE 6) generally similar to adapter 37 except that its surface slopes at an angle of 37 degrees to the plunger axis rather than at 45 degrees. The plunger is lowered a second time in the same manner as previously described to provide the double flare 80 at the tube end, it being understood that both folds of the double flare. lie at an angle of 37 degrees to the axis of the tube.

It will be recognized from the foregoing that the described flaring tool is preferably provided with a plurality of flaring adapters including conical adapters some of which slope at 45 degrees and others of which slope at 37 degrees. It is customary practice to use a single flare of 45 degrees on tubing formed of the softer metals, such as copper and aluminum, and a double flare of 37 degrees on tubing formed of steel and the harder metals. Ho ever, it is pointed out that either single or double flares may be formed on tubing of any material and that angles other than 37 and 45 degrees may be used in making either type of flare and also that either of these angles are suitable for both single and double flares if the fittings with which they are to be used have complemental seating surfaces. In addition, there is provided a complete set of adapters for the various size openings 54 and each having the general design shown in FIGURE for use in performing the first operation of the two-step double flaring operation.

Although the foregoing description deals with the use of a permanent magnet for releasably holding the flaring adapters to the plunger, it is pointed out that spring means may be used in lieu of the magnet. For example, the adapters could be provided with spring fingers formed to frictionally grip the walls of bore 33 to hold the adapters in place while allowing them to shift transversely of the plunger for self-centering purposes. Also, other spring or resilient supports of a like nature could be used.

While the particular universal flaring tool herein shown and disclosed in detail is fully capable of attaining the objects and providing the advantages hereinbefore stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as defined in the appended claims.

We claim:

1. A flaring tool for use in flaring the end of pipe to facilitate the fluid-tight coupling of the pipe to a fitting, said tool having a main frame adapted to be rigidly supported on a work bench or the like, said frame having a channel slidably supporting a pipe clamping device, plunger means slidably and reciprocably supported normally to said channel and in alignment with a pipe end seated in said clamping device, said plunger means including a flaring adapter mounted in end-to-end abutment with said plunger means adjacent the pipe end to be flared, said flaring adapter being movable crosswise of said end of said plunger means, and non-electric magnetic means mounted detachably within the said end of said flaring plunger for holding said adapter releasably to said plunger means while allowing said adapter to shift radially in any direction crosswise of the plunger end as necessary to center the adapter automatically axially of the pipe as the plunger is forced into the pipe to flare the end thereof.

2. A flaring tool as defined in claim 1 characterized in that said magnetic means comprises a permanent magnet carried on said plunger at the end thereof adjacent said pipe clamping device.

3. A flaring tool as defined in claim 1 characterized in the provision of manually operable pivoting lever means movably supported on said main frame and operably associated with said plunger for forcing said conical adapter into the end of a pipe clamped within said clamping device.

4. In a flaring tool of the type having a main frame provided with a channel adapted to slidably support a pipe clamping device having provision for clamping pipes of a range of diameters in openings thereof, a reciprocably supported plunger having a separable conical adapter on its lower end and movable toward an opening of said clamping device when an opening of the latter is aligned with said plunger, that improvement which comprises permanent magnetic means mounted on the end of said plunger for releasably clutching said conical adapter to said plunger while permitting the same to shift transversely thereof in any direction as the conical adapter is moved into flaring position within the end of a pipe undergoing flaring whereby said adapter automatically centers itself relative to the pipe end being flared as an incident to the movement of the adapter into the pipe end.

5. In a flaring tool for use in flaring pipe ends and of the type having a pipe clamping device for rigidly sup porting a pipe with the tip end thereof projecting slightly beyond one side of said clamping device, means including a reciprocably supported flaring plunger having one end positioned to be moved axially into the said pipe end to flare the same, that improvement in which said one end of the plunger includes a separable flaring adapter and permanent magnetic means for releasably holding said adapter in end-to-end abutment to the end of said plunger, said adapter having a flat base end resting flush against the juxtaposed end of said plunger and being shiftable in all directions transversely of the plunger end by contact with the rim of the pipe as the plunger is moved toward the pipe thereby automatically centering said adapter with respect to the pipe undergoing flaring, said adapter being readily replaceable by a different adapter to facilitate the performance of difierent flaring operations in succession while a given pipe remains firmly clamped in said clamping device.

6. A flaring tool as defined in claim 5 characterized in that said clamping device has the rim edges at the opposite ends of the pipe clamping opening therein flaring outwardly at different predetermined conical angles, one of said angles having a first value commonly used in providing pipe ends with a single flare, and the other of said angles having a second and diflerent value commonly used in providing pipe ends with a double flare.

7. A pipe flaring tool comprising a pipe clamping device having elongated jaws pivotally connected together near one end and provided with a range of pipe clamping openings between the mating lateral edges thereof, one end of said clamping openings having their rims conically flared at approximately 45 degrees to form single flared pipe ends and the other end of said clamping openings having their rims conically flared at approximately 37 degrees to form double flared pipe ends, reciprocable plunger means including a support therefor slidable lengthwise of said jaws as necessary to bring said plunger into axial alignment with said pipe clamping openings, said jaws being bodily reversible as a unit to present either of said conically flared rims to said plunger and then shifted bodily lengthwise of said jaws to selectively align any one of said clamping openings opposite the end of said plunger whereby any one of either the single or the double flare rims of said pipe clamping openings can be positioned opposite the end of said plunger, a plurality of unitary flaring adapter cone means readily substitutable one for another on the lower end of said plunger one of which is of the proper angle for forming a single flare pipe end and another of which is of the proper angle for forming a double flare pipe end and means for holding said adapters detachably to said plunger and free for lateral shifting movement to automatically align the adapter coaxially with the axis of the pipe end as the adapter is moved against the pipe end.

8. A pipe flaring tool as defined in claim 7 characterized in that one of said adapters has a generally cylindrical pilot having a converging tip, the other end of said pilot having an annular flange which flares outwardly and toward the converging end of said pilot and adapted to cooperate therewith in performing the first step of a double flare operation, and the other face of said annular flange being flat and radial normal to the axis of said plunger.

9. A pipe flaring tool as defined in claim 7 characterized in that said plunger is of magnetic material, the adapter supporting end thereof having an axial bore, a non-magnetic sleeve seated in said bore, permanent magnet means supported Within said sleeve, said adapters including magnetic material and being releasably but slidably supported across the end of said plunger by the magnetic field of said permanent magnet means.

10. A pipe flaring tool comprising means for rigidly clamping a pipe to be flared slightly rearwardly of the end to be flared, a reciprocably supported flaring plunger having its axis generally aligned with said pipe end, pivotally supported lever means for forcing said plunger into the pipe end to flare the same, said plunger being characterized in the provision of a conical pipe flaring adapter having a flat base normal to the adapter axis, and means carried by the end of said plunger for holding the flat base of said adapter firmly supported thereon and free to shift in any direction transversely of the plunger end as the conical surface of the adapter engages the end of a pipe to be flared whereby the engagement of said conical surface with the pipe end automatically operates to center the adapter relative to the axis of the pipe end.

11. A pipe flaring tool as defined in claim 10 characterized in that said tool includes a plurality of pipe flaring adapters for said plunger of different shapes and adapted to be readily substituted for one another independently of fastening devices in performing successive flaring operations on a given pipe.

12. A pipe flaring tool as defined in claim 11 characterized in the provision of permanent magnet means for releasably holding said pipe flaring adapters detachably to the end of said plunger.

References Cited in the file of this patent UNITED STATES PATENTS 1,331,030 Ryan Feb. 17, 1920 1,350,904 Walters Aug. 24, 1920 1,661,367 Helminiak Mar. 6, 1928 1,783,639 Canny et a1. Dec. 2, 1930 1,962,522 Paterson June 12, 1934 2,089,133 Parker Aug. 3, 1937 2,241,091 Hood May 6, 1941 2,422,800 Ransom June 24, 1947 2,464,510 Hull Mar. 15, 1949 2,595,036 Wolcott Apr. 29, 1952 2,662,575 Wolcott Dec. 15, 1953 2,723,703 Evans et a1. Nov. 15, 1955 FOREIGN PATENTS 1,020,498 France Feb. 6, 1953

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3195337 *Apr 18, 1962Jul 20, 1965Ridge Tool CoHard tube flaring tool
US3943744 *Jun 19, 1974Mar 16, 1976Tapco Products Company, Inc.Louver cutter
US4068515 *Feb 7, 1977Jan 17, 1978Gould Inc.Flaring tool
US4779441 *Apr 15, 1983Oct 25, 1988Pringle William LTube having a flared end
US5487294 *Jun 24, 1994Jan 30, 1996Bend All Manufacturing Inc.System for forming end flanges on pipes
US7069765 *Nov 14, 2003Jul 4, 2006Manchester Tool & Die, Inc.Release mechanism for end forming machine
USRE30940 *Jan 16, 1980May 25, 1982Gould Inc.Flaring tool
DE19953997A1 *Nov 10, 1999May 17, 2001Volkswagen AgProdn of an automobile exhaust catalyst housing uses a tubular fine steel workpiece which is pressed against a conical die at each end in turn to give the double-funnel shape with angled zones
DE19953997B4 *Nov 10, 1999Apr 9, 2009Volkswagen AgVerfahren zum Herstellen eines Doppeltrichters, insbesondere aus Edelstahl, für ein Katalysatorgehäuse
U.S. Classification72/317, 72/482.91
International ClassificationB21D41/02, F41A19/31, F41A19/00, B21D41/00
Cooperative ClassificationF41A19/31, B21D41/021
European ClassificationB21D41/02B, F41A19/31