US3512387A - Ring lock for tube expander - Google Patents

Description

My19, 1970 ---w.-A.AMEs 3,512,387l

RING Loox FOR TUBE EXPANDER Filed June 21, 1967 HLIIHIHIIIIIL United States Patent O U.S. Cl. 72-455 9 Claims ABSTRACT OF THE DISCLOSURE Tube expansion apparatus which includes, generally, an elevated head having a main cylinder which drives a mam ram. The main ram has a rod tooling plate affixed to its underside, to which are affixed a number of expander rods. The expander rods each have a crescentshaped ring groove eccentrically positioned on the upper portion thereof, and the rod tooling plate has a number of ring locks in it, each of which includes a ring which is biased to lockingly engage within the ring grooves in the expander rods. The expander rods are removed by rotating them 180, so as to cam the circumferential portions thereof against the rings to center them Within the expander rod apertures in the rod tooling plate, thereby permitting removal of the expander rods.

This invention relates, in general, to a ring lock construction for removably aixing expander rods in tube expansion apparatus, whereby they can be easily and quickly removed and replaced. More particularly, this invention relates to tube expansion apparatus for radially expanding a portion of a tubular member for the purpose of uniting it with a structural part having a preformed aperture for receiving the tube.

Tube expansion apparatus of the type in which this invention finds unique application are employed for the purpose of expanding the tubular member, to form cooling coils and the like for air conditioners or other heat exchange equipment. Generally, the tube expansion apparatus has a head which is elevated and includes a main cylinder which drives a main ram. At the bottom of the main ram is a rod tooling plate to which the expander rods are affixed. In the past, numerous different methods have been used to removably afl-lx the expander rods to the rod tooling plate, however', these methods have been generally unsatisfactory primarily because they require too much time and labor, in many cases, at least two men, to remove and replace the expander rods. Since the production runs for a particular size cooling coil frequently change, the down-time of the apparatus and the labor cost for making the necessary changes in placement of the expander rods is excessive.

It is an object of the present invention to provide irnproved tube expansion apparatus for radially expanding a portion of a tubular member for the purpose of uniting it with a structural part having a preformed aperture for receiving the tube.

More particularly, it is an object to provide animproved ring lock construction for removably axing expander rods within tube expansion apparatus, whereby the expander rods can be easily and quickly removed.

Another object is to provide improved ring locks for removably axing rod-like members to support means, whereby the rod-like members can be easily and quickly removed.

Still another object is to provide improved ring locks which permit the expander rods of tube expansion apparatus to be easily and quickly removably replaced therein by one man.

A still further object is to provide improved ring locks which are simple in construction.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The above objectives are accomplished with tube expansion apparatus which includes, generally, an elevated head having a. main cylinder which drives a main ram. The main ram has a rod tooling plate affixed to its underside, to which are affixed a number of expander rods. The expander rods each have a crescent-shaped ring groove eccentrically positioned on the upper portion thereof, and the rod tooling plate has a number of ring locks in it, each of which includes a ring which is biased to lockingly engage within the ring grooves in the expander' rods. The expander rods are removed by rotating them so as to cam the circumferential portions thereof against the rings to center them within the expander rod apertures in the rod tooling plate, thereby permitting removal of the expander rods.

The invention accordingly comprises the features of construction, combination of elements, and arrangement of parts which will be exemplified in the construction hereinafter set forth, and the scope of the invention will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a front plan view of a tube expansion apparatus;

FIG. 2 is a partial, bottom plan view of the rod tooling plate of the apparatus of FIG. 1, generally as viewed along lines 2-2 of FIG. l;

FIG. 3 is an exploded perspective view of a portion of the rod tooling plate, illustrating the construction of one of the ring locks therein;

FIG. 4 is a top plan view of a portion of the rod tooling plate and an expander rod, illustrating the operation of the ring lock in removably ailixing the expander rod to the rod tooling plate;

FIGS. 5 and 6 are partial sectional views generally illustrating the manner in which the expander rods are removed;

FIG. 7 is an end view, generally illustrating the ring groove formed in the expander rods; and

FIG. 8 is a partial sectional view of the expander tool of the apparatus of FIG. 1,

Similar reference characters refer to similar parts throughout the several views of the drawings.

Referring now to the drawing, in FIG. 1 there is shown a tube expansion apparatus 10 of a type using the subject ring lock including a frame 12 which is vertically supported upon a platform base 14. Aiixed to the frame 12, in an elevated position is a head 16. A main cylinder 18 is aflixed to thehead 16 and reciprocally drives a main ram 20 which is slidably supported on guide rods 22. A rod tooling plate 24 is axed to the underside of the main ram 20, and has a number of expander rods 26 removably afxed to it. The expander rods 26 each extend vertically through a pair of tooling plates 28 and 30 and a final plate 32. The nal plate 32 also supports a number of strippers 33, described more fully below. A nest tooling plate 34 is affixed to the frame, at a ixed height above the platform 14. The nest tooling plate 34 has a number of nests 36 removably affixed to it, for supporting the ends of the tubular members which are to be expanded. The apparatus 10 further includes hydraulic means 38 and motor means 40 for operating it, in the manner described more fully below.

Cooling coils are formed with the tube expansion apparatus 10, generally as follows. A number of U-shaped tubular members, usually copper tubing, are first placed in the tube expansion apparatus 10, with the curved ends thereof seatingly resting in the nests 36 supported by the nest tooling plate 34. Next, a flat rectangularend plate, a number of cooling plates in the form of thin sheets of aluminum, and a flat, rectangular top plate, each having anumber Yof preformed apertures therein, are placedin -that order in the apparatus, by extending the tubular members through the apertures therein. The cooling plates also have upstanding flanges or collars surrounding each of the apertures therein which form spacers, for maintaining the cooling plates in spaced relationship. Aportion of the tubular members are radially' expanded to unite them with the cooling plate, by means of the expander rods 26, and thereafter, the stack of cooling plates are compressed together-by means of the strippers 33 to a finished pre-determined height. Y

The strippers 33 have an axial-bore 44lin which a final i vide an inwardly tapered entrance to the ringsjwhich perexpander 46 is slidably retained. The expander rods 26 f slidably extend througl an axial bore 47 in the final expanders 46. The strippers 33 also have a cylindrical shaped cavity in their ends which form annular cavitygroovesf 48 about the final expanders 46.

After assembling the tubular members and the cooling plates Within'the tubeY expansion apparatus, the apparatus is energized to operate the main cylinder 18 toY move the main ram downwardly, to forcibly urge the ends of the expander rods 26 into the Vtubular members to radially expand them. The expander rods 26 each preferably have a Ybullet-headed carbide tip 42 (FIG. 8) aflixed to them for longer life. f'

The final plate 32 next is moved downwardly to engage the strippers with the top plate, to compress the stack of cooling plates together to a pre-determined finished height. The iinal expanders next are moved downwardly to radially expand the tubular members to provide insertion clearance for return bends, which are 180 Y tube bends. The ends of the tubular members are expanded within the confines of the annular cavity grooves between the strippers and the nal expanders. The nal expanders and the expander rods are withdrawn, and then the strippers are withdrawn. The finished cooling coil is removed from the tube expansion apparatus, and the process repeated.

As indicated above, the number of expander rods 26 and the pattern in which they are aflixed to to rod tooling plate 24 frequently change, depending upon the particular size and configuration of the cooling coil c-r the like to be fabricated. In the past, these changes each required considerable time and labor.

With the apparatus of the present invention, the expander rods 26 are adapted to be easily and quickly rerc-vably replaced, by the provision of a number of ring locks 50 in the rod tooling plate 24.

More specifically, the rod tooling plate 24 includes a ring lock plate 51, a rod alignment plate 2 and a stop plate 53 aixed together in a sandwiched construction, as can be best seen in FIGS. 3, 5 and 6. An array of horizontally and vertically aligned apertures 49 (FIG. 2) which are approximately 0.002 larger in diameter than the expander rods extendthrough both the ring lock plate 51 and the rod alignment plate 52.

The ring locks 56 are formed in the top wall 54 of the ring lock plate 51 and each includes a circular-shaped cavity S6 whieh is larger in diameter than and is concentrically disposed with respect to the aperture 49 and an elongated spring retaining slot 57 in communication with the cavity 56. A ring 58 is movably disposed within the cavity 56, and normally is biased against the side wall opposite the spring retaining slot 57, by means of a spring 60 retained within the spring retaining slot. In this position, a portion of the ring 58 is offset and overiies a portion of the aperture 49, in the manner described more fully below.

The inner diameter of the rings 58 are slightly larger than the diameter of the expander rods 26 so that the latter freely pass through them. Also, the lower peripheral inner edge of the rings 58 are beveled, as at 59, to promit the ends of the expander rods 26 to be easily inserted and extended through the rings.

The upper end of each of the expander rods 26 has a crescent-shaped ring groove 62 in its peripheral side wall, at a spaced distance from its end so that the ring groove 62 is horizontally aligned in the same plane with the cavtiy S6 and the ring 58 therein, when the end of the expander rod is'engaged with the stop plate 53. The radius R1 (FIG. 7) of thel ring groove 62 preferably is the same as the radius R2 of the expander rods 26 and is offset by a distance D1 which is equal to the groove depth D2. The groove depth DE also preferably substantially corresponds to the wall thickness of the ring 5S.

The expander rods 26 are iixedly and removably secured to the rod tooling plate 24 by inserting the ends thereof through respective onesof the apertures 49 therein and the ring 58, until the ends abut the stop plate 53.V The ends of the expander rods 26 slidably engage the beveled or tapered entrances to the rings 58, and forcibly urge the rings laterally against the biasing force of the spring 60, to thereby permitV the expander rods to pass through the rings. If the ring groove 62 in an expander rod 26 is -faced toward the spring retaininggroove 62 while the expanderrod is being inserted, the ring 58 will be forcibly urged into the ring groove 62, by the spring v60, as illustrated in FIG. 5.7YA slight audible clicking noise can be heard when the ring 58 snaps into seated position. When the ring 58 is seated in the ring groove 62, a portion of its top peripheral rim 63 (FIG. 3) lockingly engages beneath the top wall or undercut 64 of the ring groove, thereby preventing the expander rod 26 from being pulled out of the rod tooling plate.

The expander rods thereafter must be rotated to remove them. As an expander rod is rotated, the back wall 66 of the ring groove 62 slidably engages the interior surface of the ring 58 and forcibly cams the ring out of the ring groove, against the biasing force of the spring 60. As can be seen in FIG. 6, a circumferential portion of the expander rod 26 engages the interior surface of the ring 58 and centers the ring with the aperture 49, thereby permitting the expander rod to be removed simply by pulling it downwardly out of the aperture.

The final expanders 46 can be affixed to the final plate 32 with similar ring locks so that they likewise can be easily removed and replaced.

From the above description, it can be seen that the expander rods 26 can be easily and quickly removably replaced in the rod tooling plate 24, by one man. Furthermore, this can be accomplished While standing on the oor, simply by grasping the ends of the expander rods, rotating them 180 to release the rings S8 from engagement with the ring grooves 62, and pulling the expander rods downwardly. To replace the expander rods, the ends thereof are merely extended through appropriate ones of the apertures 49 in the rod tooling plate 24 and the expander rods forcibly urged upwardly to laterally displace the rings 58 in the cavities 56 until the expander rods are able to pass through the rings. Thereafter, the rings 58 snap-actingly lock within the ring grooves 62 in the expander rods 26 and prevent them from being removed until rotated. The expander rods may have to be rotated, one way or the other, to lockingly engage the rings 58 within the ring grooves 62 therein depending upon the position or the ring grooves with respect to the ring, upon inserting the expander rods within the apertures 49.

It will thus be seen that the objects set forth above, among those -made apparent from the preceding description, are eiiiciently attained and, since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention, which, as a matter of language, might be said to fall therebetween.

What is claimed it:

1. Tube expansion apparatus comprising, in combination: a main ram; and elevated head having a main cylinder aixed to it and to said main ram for reciprocally driving said main ram; a rod tooling plate affixed to said main ram having a plurality of expansion rod receiving apertures therein and a ring lock associate with each of said expansion rod receiving apertures, said ring locks each including a ring receiving cavity having a ring member laterally movably disposed therein and biasing means engaged with and normally biasing said ring member to overlie a portion of the associated one of said expansion rod receiving apertures; at least one expansion rod having a crescent-shaped ring groove in its peripheral side Wall, said expansion rod being extendable through individual ones of said expansion rod receiving apertures and through said ring member in the associated one of said ring receiving cavities said ring member being forcibly urged laterally by said expansion rod to permit it to pass through said ring member and being biased to lockingly engage within said ring groove to prevent saidexpansion rod from being removed; said ring groove being formed to cam said ring member as said expansion rod is rotated to center said ring member with respect to said rod receiving aperture, thereby permitting the expansion rod to be removed by pulling it downwardly.

2. Tube expansion apparatus, as claimed in claim 1, wherein said ring member further includes a spring receiving cavity in communication with said ring receiving cavity, and wherein said biasing means comprises a spring disposed within said spring receiving cavity.

3. Tube expansion apparatus, as claimed in claim 2, wherein said ring member has a beveled interior peripheral surface at its lower end forming a tapered entrance to said ring member, the end of said expansion rod slidably engaging said beveled surface to cam said ring member laterally to center it with said expansion rod receiving aperture to thereby permit said expansion rod to lbe passed through said ring member.

4. The tube expansion apparatus of claim 1 wherein the radius of said ring groove in said expansion rod is equal to the radius of said expansion rod and is offset by a distance which is equal to the maximum groove depth of said ring groove.

5. A ring lock for xedly and removably securing a cylindrical-shaped rod-like member within an aperture in supporting means comprising: a ring cavity Within said support means having a ring member laterally movably disposed therein and biased to overlie a portion of said aperture; a crescent-shaped ring groove in the peripheral side wall of said rod-like member for receiving an arcuate portion of said ring member therein; said arcuate portion of said ring member engaging the top and bottom edges of said ring groove and lockingly retaining said rod-like member within said aperture; said ring groove being formed to cam said' ring member as said rod-like member is rotated to center said ring member with respect to said aperture, thereby permitting the rod-like member to be removed by pulling it downwardly.

6. The ring lock of claim S, further including a spring retaining cavity in communication with said ring cavity and having a spring therein engaged with said ring member to normally bias said ring member to overlie a portion of said aperture.

7. The ring lock of claim 5, wherein said ring member has a beveled interior peripheral surface at its lower end forming a tapered entrance to said ring member, the end of said rod-like member engaging said beveled surface to cam said ring member laterally to center it with said aperture to thereby permit said rod-like member to be passed through said ring member.

8. The ring lock of claim 5, wherein the radius of said ring groove in said rod-like member is equal to the radius of said rod-like member and is offset by a distance which is equal to the maximum groove depth of said ring groove.

9. A rod lock for ixedly and removably securing a cylindrical-shaped rod-like member within an aperture in supporting means comprising: a cavity within said support means having a lock member laterally movably disposed therein and biased to overlie a portion of said aperture; a crescent-shaped groove in the peripheral side Wall of said rod-like member for receiving a portion of said lock member therein; said portion of said lock member engaging the top and bottom edges of said groove and lockingly retaining said rod-like member Within said aperture; said groove being formed to cam said lock member as said rod-like member is rotated to center said lock member with respect to said aperture, thereby permitting the rod-like member to be removed by pulling it downwardly.

References Cited UNITED STATES PATENTS 1,442,223 1/ 1923 Knebusch 287-119 1,896,645 2/1933 Pfauser 287-119 2,799,340 7/ 1957 Mueller 72-476 3,269,168 8/1966 Anderson 72-462 3,347,293 10/1967 Clark 287-119 CHARLES W. LANHAM, Primary Examiner G. P. CROSBY, Assistant Examiner U.S. Cl. X.R. 72-462, 476

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