US3151657A - Sheet metal forming machines - Google Patents

Description

Oct. 6, 1964 R. BERANEK 3,151,657

SHEET METAL FORMING MACHINES Filed March 22, 1961 3 Sheets-Sheet 1 IN VEN TOR. RUDOL PH HERA NE K BY MAHONEY. MILLER & RAMBO A TTORNEYS.

Oct. 6, 1964 R. BERANEK 3,151,657

,SHEET METAL FORMING MACHINES Filed March 22, 1961 3 ShegEs-Sheet 2 IN VEN TOR. RUDOLPH HERA NEK BY 4! MAHONEY. M/LLER8 RA B0 AT TORNE Y5.

Oct. 6, 1964 R. BERANEK SHEET METAL FORMING MACHINES Filed March 22, 1961 3 Sheets-Sheet 3 IN V EN TOR. RUDOLPH BERA NE K BY MAHONEY, MILLER & RAMBO 7 5y km 4% ATTORNEYS.

United States Patent O 3,151,657 SHEET METAL FQRMING MACHlNES Rudolph Beranelr, Columbus, Ohio, assignor to United Sheet Metal Co., Inn, Eolnmhus, Ghio, a corporation of @hit) Filed Mar. 22, 1961, Ser. No. 97,501 3 Claims. (Cl. 1532l) This invention relates to sheet-metal forming machines and to a method of forming parts thereon and, more particularly, to new and useful improvements in a spinning machine for forming parts from lightweight sheet-metal pipe and to a method of integrally forming tubular sheetmetal T-fittings.

It has been the usual practice to fabricate tubular sheetmetal T-fittings of the type commonly utilized in heating and ventilating or air conditioning systems by welding a short cylindrical flange to the outer wall surface of a main tubular body section forming a lateral extension thereof. This method necessitates the precise cutting of a circular opening in the tubular wall of the main body section corresponding in size to the desired laterally eX- tending cylindrical flange. An obvious major difilculty encountered is in the cutt ng of this opening which is further increased. when the main tubular body section is also cylindrical as the opening is then irregularly shaped. In the latter instance, the end of the cylindrical flange welded to the main body section must also be arcuately cut to conform with the cylindrical surface to provide an intersection capable of being welded. Another inherent disadvantage of this method of fabrication is that a'highly skilled technician is requ red to perform the Welding operation. As a consequence of the numerous and difficult operations involved in the above-described method of fabrication, an excessive amount of time and labor is utilized resulting in a correspondingly large cost per unit. Also, the performance of T-fittings fabricated in accordance with the above-described method has con found to be unsatisfactory when utilized for the transmission of fluids in heating and ventilating or air conditioning systems. This results from the sharp corners formed at the intersection of the main body section and the laterally extending flange which disrupt the laminar fluid flow pattern and unnecessarily impede the transmission of fluids thereby reducing the eficiency of such T-iittings and correspondingly increasing their cost of operation. Therefore, it is the primary object of this invention to provide a spinning machine and method for the rapid and economical fabrication of T-ittings from tubular sheet-metal pipe and to provide an integrally formed tubular sheet-metal T- fitting having superior fluid transmission characteristics resulting from a smooth, rounded intersection.

A further object of this invention is to provide a spinning machine having a rotatable spinning tool and a shaping mandrel readily adaptable for use on a vertical mill or radial drill wherein the spinning tool is inserted in a pre-cut or pre-punched hole in the wall of a cylindrical sheet-metal tube and thereafter withdrawn as it is rotated integrally forming a T-fitting.

In the preferred embodiment of this invention the spinning machine for fabricating tubular sheetmetal T-fitt'ngs has a rotatable spinnim tool comprising a radial arm, rotatable about an axis at one end thereof, supporting an inclined spinning roller assembly adjustable longitudinally with respect to the radial arm and thereby capable of ac conm-ioclating a varying range of T-fitting sizes and having a supporting and shaping mandrel assembly for precisely and securely positioning a T-fitting blank with respect to the spinning tool.

The accompanying drawings illustrate the present preferred embodiment of the spinning machine of this invention, the method accomplished with it and the resulting product.

in these drawings:

FIG. 1 is a front vertical view of a spinning machine embodying the present invention;

FIG. 2 is a horizontal sectional view of a spinning machine showing the table, mandrels and spinning tool thereof taken on line 2-2 of FIG. 1; a

FIG. 3 is a vertical sectional detail of the mandrels and spinnin g tool taken on line 3--3 of PEG. 4;

FIG. 4 is a vertical sectional detail of the mandrels and spinning tool taken on line 4-4 of FIG. 3;

Phi. 5 is a diagrammatical vertical sectional detail showing the spinning tool positioned within the mandrels and a sheet-metal tubing blank clamped between the mandrels;

FIG. 6 is a diagrammatical vertical sectional detail showing the spinning tool operating on a partially formed T-itting;

FI 7 is a diagrammatical vertical sectional detail showing the spinning tool finishing the upturned annular flange of a T-fitting;

FIG. 8 is a perspective view of a sheet-metal tube blank with a pre-punched starting hole; and

FIG. 9 is a perspective view of a completed T-fitting made with a preferred embodiment of the spinning machine and according to the method of this invention.

Referrin to the drawings, particularly FIG. 1, the present embodiment of the spinning machine of this invention com rises in general a vertical milling machine ll? having a vertical supporting standard 11, a mill head 12 vertically disposed and rigidly mounted on the standard 11 at the upper end 13 thereof, a horizontally disposed work-supporting table 7.4 mounted on the standard 11 at the lower end 15 thereof and movable both horizontally and vertically, and a spinning tool 16 rotatably mounted on the mill head 12. The present embodiment of this invention is advantageously adapted to a common vertical milling machine as the table 14 of such a machine is conveniently adjustable in three directions, that is, longitudinally and transversely in a horizontal plane, and vertically toward and away from the mill head 12, for precisely positioning a tubular, sheet-metal pipe blank 17 relative to the spinning tool 16. However it is contempla'ted that the present invention may also be readily adapted for use on a radial drill or other similar machines equally capable of providing the required rotational motion of the spinning tool and of precisely positioning a T- tting blank 17 and spinru'ng tool relative to each other.

The spinning tool 16, as is best shown in FIGS. 1, 3 and 4, comprises a radial arm 18, a mounting shaft 1? and a spinning roller structure 29. The radial arm 18 is of an elongated rectangular bar configuration horizontally disposed and parallel to the surface of the table 14. Rigidly arllxed to the upper horizontal surface 21 of the radial arm 18 at a point intermediate of its ends 22 and 23, is the vertically disposed, cylindrical mounting shaft 19 of a diameter suitable for insertion in the chuck on the usual type of tool spindle 24 incorporated in the mill head 12. The spinniru roller structure 2% is slidably mounted on the lower horizontal surface 25 of the arm 18 and is capable of longitudinal adjustment to increase or decrease its radial distance from the central vertical axis of the mounting shaft 19. All components of the spinning tool 16 are constructed of steel appropriately hardened for the specific utilization.

In the present embodiment, the radial arm 18 is conveniently fabricated as a composite structure to obtain a more satisfactory structural strength and to utilize more economical machining operations. The basic structure of the radial arm 18 consists of an elongated rectangular bar 26 with the shaft 1? affixed to its upper horizontal relationship with the lower horizontal surface .25. pivot bolt 35 extending vertically through the cam 33 at .cam one-half revolution about. its eccentric axis.

the bar 26, vertically disposed, flat rectangular plates 28 and28a are rigidly attached, respectively, as for example, by the bolts 29. Each plate 28 and 23a extends substantially the length of the bar 26 and is of a widthv greater than the sides 27 and 27a of the bar 26 to extend below the lower horizontal surface 25 andform an open-bottom channel therewith. A flange 39 and 30a is integrally formed along. the lower longitudinal marginal edges 31 and 31a of the plates 28 and 28:: extending laterally toward the center of the radial arm 18 thereby restricting the open-bottom channel to a cross-sectional T-shape. Trans- 1 versely across one end 22 of the bar 26, a flange 32 is integrally formed extending vertically downwardly from mounted on a base 34 of the cylinder in a contacting 'A its eccentric axis is threadedly engaged with the radial V 4 i tool 16. The opposite or lower end 48 of the spindle 33 has an integrally formed flange 49 laterally disposed and extending around the circumference of the spindle.

to provide a thrust bearing surface 51 for the roller 39. The roller 39 is an elongated cylinder with a. central longitudinal bore extending through the cylinder and is rotatably positioned on the spindle 38. The lower end 51 of the roller 39 is in a contacting relationship with the flange 4? and has a smooth machined bearing surface formed thereon. 'The corner at the juncture-of the end 51 and the cylindrical surface of the roller'39 is formed with a small radius. The upper end 52 of the roller 39 is arcuately curved forming a hemispherical surface.

arm 18. The diameter of the cam and its degree of a eccentricity are determined by the length of offset or longitudinal motion required for proper adjustment of the roller structure 20 with respect to the mounting shaft 19. If necessaryffor the specific application, the side plates 28 and 28a may be accordingly cut out to readily accommodate the particular cam size utilized. The cam 33 is advantageously mounted to permit the maximum and minimum positions to be attained by rotating the A handle 36 is rigidly attached to the cam 33 on its cylindrical surface to facilitate its operation, Although'a circular ca'mhas been described to obtain the necessary retilinear adjustment, it is to be understood that other mechanisms may be utilized equally well; For purposes of illustration, it is contemplated that an irregularly shaped cam or a feed screw mechanism; or a system of indexing pins and associated holes would prove equally suitable.

-, The spinning roller structure'20, comprising a mounting block 37, a spindle 38 and a spinning roller 39, is

slidably mounted on the lower horizontal surface of. the radial arm 18 by the T-channel previously described.

The mounting block 37 is rectangularly shaped with'the upper portion 40, which is engaged by the radial arm 18,

being provided with integrally formed flanges 41 and 41a 1 extending laterally from the sides 42 and 42a and longitudinally-disposed along the upper portion 40"thereby forming a cross-sectional T-shape corresponding to that V of the T-channel on the radial arm 18 as is shown by FIG.

3. The upper portion 46] of the mounting block 3'? with 'its associated flanges 41 and 41a is slidably engaged by lower surface 44 with the inclination being upwardly toward the radial arm 18 and outwardly toward the flange '32.. A cylindrical hole 45 is bored in the central portion of the inclined surface 44 and perpendicular thereto for reception of the end 46 of the elongated cylindrical spinning roller spindle 39. A set screw 47, as shown by FIG. 4, is conveniently utilized by the present embodiment to rigidly secure the spindle 38 in its associated hole 45. The sphidle 33 is of course perpendicularly positioned with respect to the inclined surface 44 to provide the predetermined inclination of the spinning roller 39 with respect to the vertical axis of the spinning intermediate the block 37 and the flange 32 on the bar 2 6 and within the area defined by the aforementioned T.- channel are arranged a multiplicity of compression springs 53, ofwhich only one is shown in FIGS. 1 and 4, extending longitudinally of the radial arm 18 and being in an end contacting relationship with the flange 32 and the block 37. The length of the compression springs 53 are accordingly determined by the distance between the flange 32. and the block 37 to maintain the block 37in a contacting relationship with the cylindrical surface of the cam 33 at all times. been found advantageous toutilize three compression springs but the number may be varied as is dictated by the resilient characteristics of the particular springs utilized. Elongated, cylindrical, retaining pins 54, or guide pins, only one bein shown on the drawings, of a diameter slightly smaller than the internal diameter of the springs are coaxially positioned within the springs 53. Each pin 54 longitudinally extends beyond the springs with the end portions 55 inserted within the correspondingly sized holes drilled in the adjacent vertically disposed side 56 of the block'37. The pins 54, in the present embodiment,

arerigidly secured to the block 37 by the convenient holes 58, of which only one is shown in FIG. 4, located 7 in the flange 32 and extending entirely through the flange parallel to the longitudinal axisof the radial arm 18I This completes a detailed description of the spinning tool as illustrated by the present embodiment. Although the spinning tool described utilizes only one spinning roll er, it is contemplated that necessary modifications may be 7 made to utilize at least one additional roller (not shown),

similar to the one herein described, positioned diametrically opposite on a longitudinal extension of the radial arm. Such a multiple roller arrangement would be par ticularly advantageous in forming large diameter T-fittings as the forces encountered in the spinning operation would be counterbalanced thereby reducing the resultant stresses. The spinning operationwould also be improved as a multiple roller tool could be rotated at an increased speed with a consequent reduction of time consumed to complete the spinning operation and a decreased cost of production. a a

The sheet-metalpipe supporting mandrel 59 is an open ended, inverted U-shaped channel positioned with its longitudinal axis parallel to that of the table 14. The top portion cc of the mandrel 59 is arcuately curved in a transverse direction forming a cylindrical surface, as is best shown by FIG. 3, for the internal support of a tubular pipe blank 17. As a pipe blank 17 is placed over 7 the mandrel 59, the radial dimensionof the arcuately curved top portion 60 is determinedby the diameter of the smallest sheet-metal pipe to be utilized in conjunction with a specific support mandrel as is its length. However, larger diameter sheet-metal pipes mayalso be satisfactorily supported by the same mandrel as it is not necessary that a supporting surface be in contact with more than a small arcuate segment of a tubular pipe wall.

In the present embodiment, it has' Each longitudinal marginal edge 62 and 63 of the armately curved top portion terminates in straight, vertically disposed side portions 64 and 65. A section is cut out of the mandrel 59 at the central portion intermediate its ends 66 and 67 forming a generally circular opening 68 having its central axis vertically disposed to the longitudinal surface of the mandrel 59 and having communicating downwardly extending notches 68a. It will be noted that the circular opening es is formed in the armately curved top portion of the mandrel and the notches fizz are formed in the side portions 64 and of the manrh'el. The dimeter of the cylindrical opening 68 is sufficiently large to provide adequate clearance for rotation of the spinning tool 16 when it is inserted within the mandrel and the communicating notches 68a cooperate in providing such clearance. Across each open end 66 and s7 of the mandrel 59, horizontally disposed rectangu lar bars 69 and 6941 are rigidly attached, as for exmple by welding, interconnecting the vertical side portions 64 and 65 but not extending outwardly beyond such portions to provide a supporting abutment external to the main body of t-Lfi mandrel. Equally dimensioned removable rectangular support blocks 7%) and 7% are disposed between the bars 69 and 69a and the table 14 to maintain the mandrel 59 at a predetermined distance above the table 14 to provide suficient clearance for sheet-metal pipe bi k 17 positioned on the mandrel.

The tubular sheet-metal pipe clamping and shaping mandrel 71 is an open ended, inverted semicircular channel, the internal radius of which is greater than the external radius of the arcuate top portion 66 of the supporting mandrel 59, and which is concentrically positioned over such top portion of the mandrel 59. As this mandrel 71 is utilized in shaping the laterally extending flange of a T-fitting, its internal radius must correspond to that of the pipe blank 17 with which it is utilized and a mandrel must be designed for each specific size pipe blank 17 that will be utilized. The length of the mandrel 71, of course, need only be sufficiently greater than the diameter of the laterally extending flange of the T-iitting to be formed to provide an adequate clamping surface. In the central portion of the mandrel 71 intermediate its ends 72 and 72a, a circular opening 635, having its central axis vertically disposed to the longitudinal surface of the mandrel, is formed which coincides with the central vertical axis of the c rcular opening 68 in the supporting mandrel 59. A cylindrical flange 73 laterally extending from the external cylindrical wall 74 of the mandrel 71 is disposed around the circular opening 6812 providing a shaping mandrel for the laterally extending flange of the T-fitting to be fabricated. The intersection of the cylindrical flange 73 and the inner cylindrical surface 75 of the mandrel 71 is constructed with a radial corner 73a to avoid an abrupt change in cross-section from the main longitudinal body of the mandrel to the laterally extending flange 73.

The work-supporting and clamping mandrels 59 and 71, as shown in FIGS. 1 and 2, are positioned on and removably secured to the mill Work table 14 by appropriately positioned clamps of the type commonly used for temporary machine set ups. That is, T-head bolts 7 6 of suitable length are positioned in the T-slots 77 of the table 14 adjacent to the mandrels to provide the required clamping force. Rectangular clamping bars 73 are engaged at a point intermediate their ends by the bolts 76 and secured thereto by nuts 79 cooperatively threaded on one end of the bolts. One end of the bars 78 are in contacting engagement with the cross bars 69 and 69a of the mandrel 59 and the external surface 74 of the mandrel 71, with which they are respectively associated. The opposite or outer ends of the bars 78 are supported by removable rectangular blocks 39 and 81 which are of a height equal to that of the mandrels 59 and 71 respectively. T ightening the nuts 79 draws the bars 73 into engagement with 6 their respective mandrels securing the assembly to the table 14.

The tubular sheet-metal pipe blank 17 utilized in forming the finished article with the present embodiment of the spinning machine comprises an elongated tubular main body section 82 as shown by FIG. 8 with its diameter and length being determined by the physical dimensions of the desired finished article. A slot 83 is cut or punched in the cylindrical wall of the body section 82 at a point intermediate the ends 84 and 85 thereof to remove the excess metal which is not required in the formation of the laterally extending flange and to provide an opening in which to insert the spinning tool 16 for the spinning process. The slot 83 is an elongated slot with arcuate end portions 86 and 87 of equal curvature interconnected by the parallel straight sides 83 and 89 tangential to the arcuate end portions 86 and 87. The slot 83 is longitudinally disposed with respect to the body section 82 providing a larger amount of metal for formation of the cylindrical side portions of the laterally extending flange laterally disposed from the central longitudinal axis of the slot 83.

A tubular sheet-metal T-fitting 9i fabricated in accordance with the method of this invention and utilizing the present embodiment of the spinning machine comprises a main body section 91 with a laterally extending cylindrical flange 92 as is illustrated by FIG. 9. The main body section 91 consists of an elongated cylindrical sheet- 1 etal pipe having a circular opening 93 in the cylindrical wall positioned intermediately of its ends 94 and 95. Annularly disposed around the opening 93 is the cylindrical flange 92 laterally extending from the main body section $1 with its open end 9% uniformly disposed from the central longitudinal axis of the main body section 91. The flange 92 is integrally formed with the main body section 91 with the annular intersection 97 therebetween axially curved with respect to the central vertical axis of the flange 92 presenting a smooth rounded transition from the internal cylindrical surface of the main body section 91 to the internal cylindrical surface of the flange 92.

To fabricate a T-fitting of the form illustrated in PEG. 9 utilizing the present embodiment of the spinning machine, a tubular sheet-metal blank 17 is positioned between the mandrels 59 and 71 with the shaft 19 of the spinning tool 16 centrally aligned in the mandrel openings. Rotating the shaft 19 revolves the roller 39 about the axes of the mandrel openings to spin the flange 92 in conformance with the laterally extended flange 73 of the mandrel 71. For purposes of properly mounting the blank 17 on the mandrels, it is necessary to remove mandrel 71 which is readily accomplished by removing the clamping bars 78 associated therewith. The clamping bar '78 and the supporting block 70 associated with cross bar 69 are also removed to permit the blank 17 to be placed on the mandrel 59. The mandrel 71 is then replaced, as are the clamps previously removed, with the openings in the mandrels 59 and 71 and the slot 83 concentrically aligned. The table 14 of the mill 12 with the attached mandrel assembly is then horizontally and vertically adjusted to position the roller 39 of the spinning tool within the aligned openings of the mandrels 559 and 71 and the blank 17. Initially positioning the spinning roller structure 20 at its minimum radius by the cam 33, power is applied to the mill head 12 causing the mill head spindle 2 4 with the spinning tool shaft 19 inserted therein to rotate and the table 14 is gradually lowered bringing the peripheral edges of the slot 83 into contact with the cylindrical surface of the roller 39 near its upper end 52 as illustrated by FIG. 5. Further lowering the table 14 causes the cylindrical wall of the blank 17 to be spun upwardly into the cylindrical area defined by the flange 73 of the mandrel 71 as the radius of the revolving movement of the roller 39 contacted by the blank 17 is gradually increased as a consequence of the inclination of the roller 39. FIG. 6 illustrates a partially formed or upset flange portion 92a. Loweringthe table 14 still further brings the radial corner at the lower end 51 of the roller 39 into contact with the blank 17, as indicated by FIG. 7, spinning the flange to its final shape indicated at 92 which corresponds to the shape of the internal cylindrical sur face of the flange 73. This completes the spinning operation andthe fabrication of a tubular sheet-metal T-fltting 90 and the T-fitting may then be removed from the mandrels .59 and 71 by removing the clamps and the mandrel 71. If a larger diameter flange 92 is desired, the radial position of the spinning roller structure is increased 'by rotating the cam 33 toward its maximum position and repeating the spinning operation. In this instance, an appropriate larger diameter flange 73 on the mandrel 71 must also be used for the initial spinning operation. As an alternative method, provided the sheet metal utilized in the fabrication of the blank has the required ductility, the initial spinning operation with the spinning roller struc ture 20 adjusted to its minimum radius may be eliminated and a larger appropriate radius may be used to revolve the rollerthrough a path appropriate to produce a flange tioned with its axis eccentrically located therein and the' roller is revolved vbodily through a path which extends beyond the area of the opening so as to upset the metal at the edge of the opening to form the upstanding flange. The upsetting operation may be performed all at once or the extent of the revolving path of the roller may be gradually increased to progressively upset the metal adjacent'the opening so as to gradually form the flange.

It can be readily seen that the fabrication of tubular sheet metal T-fittin s as illustrated by FIG. 9 is greatly facilitated by the utilization of a spinning machine as herein described. The present embodiment greatly reduces the separate operations required and in particular the costly time and labor-consuming cutting and Welding operations. Central manufacturing plants can, therefore, advantageously produce the various sizes of T-fittings commonly utilized in heating and ventilating or air conditioning systems with a consequent reduction of cost as. compared with the more usual field fabrication methods previously described. In addition, T-fittings fabricated in accordance with the method of this invention possess superior fluid transmission characteristics as a consequence of integrally forming the laterally extending flange with the main body section with a gradually rounded merging intersection. This greatly reduces the impedance to the fluid flow increasing the efliciency of systems utilizing such T-fittings and thereby lowering their cost of operation.

According to the provisions of the patent statutes, the principles of this invention have been explained and have been illustrated and described in what is now considered to represent the best embodiment. However, it is to be understood that, within the scope of the appended claims,

the'invention may be practiced otherwise than as specifically illustrated and described.

7 Having thus described this invention, What is claimed is: 1. A spinning machine for the fabrication of tubular sheet metal T-fittings comprising a spinning head attached to a vertical supporting standardand a work supporting table mounted on the said vertical supporting standard, said spinning head having a spinning tool rotatably l 5 mounted thereon by a vertically disposed mounting shaft, said spinning tool having an arm radially extending from said mounting shaft and a cylindrical spinning roller angularly disposed to said arm, said roller extending downwardly from said arm and outwardly from the central vertical axis of said mounting shaft, said roller also being longitudinally slidably mounted on said arm and freely rotatable about its inclined axis, said work supporting table and said spinning head being movable vertically relatively, said table having removably attached thereto an elongated longitudinal tubular work supporting mandrel with an annular opening vertically positioned there n intermediate its ends, sa d table also having an elongated semicircular clamping mandrel positioned on the supporting mandrel and having an upstanding cylindrical shaping flange vertically disposed to said mandrel, said clamping mandrel,

being positioned over said supporting mandrel with said opening in the supporting mandrel and the flange of said clamping mandrel concentrically aligned with the vertical axis of the said mounting shaft.

2. A spirming machine for the fabrication of hollow sheet metal T-fittings comprising a spinning head attached to a supporting standard and a work-supporting table mounting on the supporting standard, said spinning head having a spinning tool rotatably mounted thereon by a mounting shaft, said spinning tool having an arm radially extending from the axis of said mounting shaft and a spinning roller on said arm having its axis angularly disposed relative to the shaft axis, said roller being adjustable along the arm and rotatable about its axis, said Worksupporting table and said spinning head being relatively movable on said standard toward and away from each other, said table having mounted thereon a work-supporting mandrel with an opening formed therein having an axis adapted to be aligned with the axis of said shaft, said table also having a clamping mandrel adapted to be positioned over said supporting mandrel and having an outwardly projecting flange adapted to be concentrically disposed with said opening in the supporting mandrel.

3. A spinning machine for the fabrication of hollow sheet metal T-flttings comprising a spinning head and a Wor '-support ng unit, said' spinning head including an arm extending radially from a supporting shaft and supporting a spinnin roller with its axis at an angle relative to the shaft, said work-supporting unit and said spinning head being relatively movable in the direction of the shaft axis, said work-supporting unit comprising a supporting mandrel with its axis disposed transversely of the shaft axis and having an opening with its axis adapted to be aligned with the shaft axis, and a clamping mandrel adapted to be positioned over said supporting mandrel and having an outwardly projecting flange adapted to be concentrically disposed relative to said opening in the sup-. port'mg'mandrel.

References Cited in the file of this patent UNITED STATES PATENTS

Claims (1)

1. A SPINNING MACHINE FOR THE FABRICATION OF TUBULAR SHEET METAL T-FITTINGS COMPRISING A SPINNING HEAD ATTACHED TO A VERTICAL SUPPORTING STANDARD AND A WORK SUPPORTING TABLE MOUNTED ON THE SAID VERTICAL SUPPORTING STANDARD, SAID SPINNING HEAD HAVING A SPINNING TOOL ROTATABLY MOUNTED THEREON BY A VERTICALLY DISPOSED MOUNTING SHAFT, SAID SPINNING TOOL HAVING AN ARM RADIALLY EXTENDING FROM SAID MOUNTING SHAFT AND A CYLINDRICAL SPINNING ROLLER ANGULARLY DISPOSED TO SAID ARM, SAID ROLLER EXTENDING DOWNWARDLY FROM SAID ARM AND OUTWARDLY FROM THE CENTRAL VERTICAL AXIS OF SAID MOUNTING SHAFT, SAID ROLLER ALSO BEING LONGITUDINALLY SLIDABLY MOUNTED ON SAID ARM AND FREELY ROTATABLE ABOUT ITS INCLINED AXIS, SAID WORK SUPPORTING TABLE AND SAID SPINNING HEAD BEING MOVABLE VERTICALLY RELATIVELY, SAID TABLE HAVING REMOVABLY ATTACHED THERETO AN ELONGATED LONGITUDINAL TUBULAR WORK SUPPORTING MANDREL WITH AN ANNULAR OPENING VERTICALLY POSITIONED THEREIN INTERMEDIATE ITS ENDS, SAID TABLE ALSO HAVING AN ELONGATED SEMICIRCULAR CLAMPING MANDREL POSITIONED ON THE SUPPORTING MANDREL AND HAVING AN UPSTANDING CYLINDRICAL SHAPING FLANGE VERTICALLY DISPOSED TO SAID MANDREL, SAID CLAMPING MANDREL BEING POSITIONED OVER SAID SUPPORTING MANDREL WITH SAID OPENING IN THE SUPPORTING MANDREL AND THE FLANGE OF SAID CLAMPING MANDREL CONCENTRICALLY ALIGNED WITH THE VERTICAL AXIS OF THE SAID MOUNTING SHAFT.

Images