US2890737A

US2890737A - Tube beading apparatus

Info

Publication number: US2890737A
Application number: US519354A
Authority: US
Inventors: John C Cleaver; Grobecker Hugo Herman; Fred G Wiegratz
Original assignee: Cleaver Brooks Co
Current assignee: Cleaver Brooks Co
Priority date: 1955-07-01
Filing date: 1955-07-01
Publication date: 1959-06-16
Anticipated expiration: 1976-06-16

Description

June'16, 1959 J. c. CLEAVER ET AL 2,890,737

TUBE BEADING APPARATUS Filed July 1, 1955 2 Sheets-Sheet 1 Ljbhn Gam 7 Hggaflermanfimbecker; I gred CZ Z1] June 16, 1959 J. c. CLEAVER ET AL 2,890,737

I TUBE BEADING APPARATUS V Filed July 1, 1955 2 Sheets-Sheet 2 A L bhn CI (leave);

TUBE BEADING APPARATUS John C. Cleaver, Hugo Herman Grobecker, and Fred G. Wiegratz, Milwaukee, Wis., assignors to Cleaver-Brooks (Iompany, a corporation of Wisconsin Application July 1, 1955, Serial No. 519,354

7 Claims. (Cl. 15381) This invention relates to apparatus for making a bead on a previously flared tube and more particularly to a semi-automatic machine for beading boiler tubes into a tube sheet.

Workmen, skilled by years of experience, have be come fairly proficient at beading the end of a tube into a tube sheet of a boiler by the use of an air hammer and a tool member having an outer end shaped much like the thumb and forefinger of a persons hand. This tool is used with the forefinger part extending into the interior of the tube with the primary beading force being applied in the curve of the finger between the thumb and forefinger.

The tube head is made on the outside of the tube sheet to seal the tube in the sheet and also to secure it against accidental removal. The bead is ordinarily of hemi-torous shape and is formed by the workman starting with a tube which has been flared slightly. The operation requires that the air hammer be directed at the tube head at an angle to the inside surface of the tube and gradually changed until the finishing operation is done with the air hammer at an angle to the outside of the tube. Considerable practice and skill are required before a workman can produce a satisfactory tube head which is smooth and regular in appearance as well as satisfactory structurally.

It is the primary object of this invention to provide an apparatus which may be used by an unskilled operator to bead a tube tightly against a tube sheet.

It is another object of this invention to provide an apparatus for beading a tube which automatically carries a tube beading tool through a sequence of proper positions to form the tube bead.

A further object is to provide an apparatus of the character described which can bead tubes successfully at a much more rapid rate than can be done by a skilled workman.

Another object is to provide an apparatus of the character described which will automatically carry a heading tool through the same positions and operation on each successive tube that is headed with the tool so that all the beads Will be uniform.

Other objects, features and advantages of the present invention will be apparent from the following description of a preferred embodiment of the invention illustrated in the accompanying drawings, in which:

Figure 1 is a perspective view of the apparatus of this invention taken from the side and looking toward the apparatus in its usable position;

Figure 2 is a fragmentary perspective view of the machine in operative relation to a tube being beaded with parts of the machine removed for clarity of illustration of the operating mechanism;

Figure 3 is a fragmentary perspective view of the mechanism for moving the heading tool across the tool holder of the apparatus; and

Figure 4 is a fragmentary sectional view through the hired States Patent connection between the supporting frame and the rotatable parts of the apparatus.

While we have shown and will describe a preferred embodiment of our invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made Without departing from the spirit and scope of the invention as disclosed in the appended claims.

The tool illustrated in the drawings of this invention is particularly adapted to place a radius head on a previously flared tube in a boiler. The machine or apparatus is air driven and under the control of an operator who need not be skilled in tube beading in order to properly operate the apparatus. The beading is performed by a standard air gun and beading tool member mounted in the air gun. The gun is, however, mounted in the apparatus and is moved relative to the flare of the tube to be headed in such a manner that a properly shaped bead is made on the tube end. Compressed air is supplied to the air gun separately from the supply of air to the motor of the apparatus which causes the movements of the gun relative to the tube.

As illustrated in Figure l of the drawings, the apparatus has a supporting member or frame which includes a tubular portion 5 to which an upstanding plate 6 is secured in order to provide a plate 7 to which an eye 8, substantially over the center of gravity of the machine, may be placed. A small link 9 is passed through the :eye so that a crane hoist hook may be easily attached to the eye for supporting the machine opposite the end of a boiler in a workshop.

The operator works from the rear or frame end of the machine and a pair of hollow handles 10 and 11 are provided with air line nozzles 12 so that air lines may be connected with the apparatus. One such air line 13 is illustrated as connected with the far handle 11 and the admission of air from the supply line 13 is controlled by a thumb button operated valve 14. A similar button operated valve 15 is provided on the near handle 10. The air thus led into the machine is used for either operating the beading tool itself or for providing the movements of the mechanism which supports the air tool. In the latter case, an air motor 16 is supplied with air through a hose 17 controlled by the push button valve 15, the motor being supported on a depending plate 18 attached .to the cylindrical frame 5.

In general, the portion of the apparatus in front of the frame just described above is mounted for rotation about a longitudinal axis. Thus, a tool holder, generally indicated as 20, is mounted on the frame of the machine in such a manner that rotation of a large gear 21 next to the upstanding plate 6 will rotate the entire tool holder 20. In general, the motor shaft 22 of the air motor 16 is provided with a smaller gear 23 in mesh with the larger gear 21 in order to rotate the entire tool holder. In theparticular embodiment illustrated, the tool holder rotates at approximately 15.6 r.p.m. To bead a tube requires about six revolutions so that it is immediately evident that a tube may be headed in a matter of 25 seconds.

The structure of the tool holder 20 may best be seen from Figures 2 and 4. The tool holder has a cylindrical bearing 24 mounted upon a bronze sleeve 25 placed about a tubular hub 26 of the frame 5. The large gear 21 is mounted on a ring 27 keyed as at 28 to the cylindrical bearing 24.

Bronze washers

29 and 30 at opposite ends of the bronze bearing maintain the cylindrical bearing 24 against longitudinal movement on the bronze sleeve hearing 25. Y

The tool holder itself comprises a pair of heavy parallel plates 31 spaced apart and joined at their rearward portions by a cross plate 32 which is welded or otherwise secured to the cylindrical bearing 24. Thus, the bearing and plates which form the housing of the tool holder are constructed as a unit and are braced at their forward ends by a pair of spacers 33 and rigidly secured together at the end nearest the large gear. Extending forwardly from the medial portion of the heavy plates 31 are a pair of straps 34 joined at their outer end by a block member 35 in which a pilot or guiding member in the form of a short cylinder 36 is secured so as to enter a tube to be beaded. In Figure 2, the pilot 36 is shown as inside the open end of a tube T which has been partially flared into a tube sheet S, the apparatus being in proper position to cause, the beading operation. A stop in the form of an adjustable pin 37 may be mounted on the block member 35 so that the tool will notlbe placed too close to the tube.

The actual beading operation is done by a standard air gun 46 in which is secured a beading tool member 41 having a pair of fingers 42 and 43 simulating the joined finger and thumb of a persons hand. The curved portion of the tool between the fingers performs the beading operation upon the tube by a series of hammer blows. The shank of the tool member 41 passes through an opening'38 formed in the end plate 35 secured to the forwardly extending arms 34 in between which the air gun operates. In the particular embodiment illustrated, the air hammer 48 operates at approximately 3,000 strokes per minute or, in other words, the heading tool would give'3,000 impacts against the tube end in performing a beading operation should it be of one minutes duration; Since a tube may be headed in 25 seconds as stated above, approximately 1,250 impacts would be received by the tube end.

Air is supplied directly to the air hammer through the hose' 13 illustrated in Figure 1 and the control valve 14 from which the air is' led through the hose section 44 to piping 45 extending on into the frame and toward the tool as illustrated further in Figure 4 to a swivel connection 46. The swivel connection is on the axis of rotation so that rotation of the toolholder will not interfere withthesupply' of air to the air hammer. As further illustrated in Figure 1, a flexible hose'section 47 takes the air from the swivel connection to the air hammer 40.

It will be noted from the description of the apparatus above that rotation of the tool holder will carry the beading air hammer in a circular path. The'tool member 41 is positioned on a line of action which crosses the axis of rotation of the tool holder. The position illustrated in Figure'Z is the starting position of the air hammer in performing the heading action on a previously flared tube. As illustrated, the line of action of the tool member is at approximately .a 15 angle to the inside wall of the tube; At this position, the beading operation may start and the revolutions of the tool holder will carry the hammer progressively around the periphery of the tube end. It is desirable that the beading tool member be gradually and progressively swung outwardly through a position where the line of action is parallel to the tube axis to a position where the line of action is at approximately a angle to the outside wall of the tube for the finishing operation.

The apparatus of this invention is so constructed that the line of action of the heading tool is automatically carried through the angular relations specified above relative to the tube Walls. In order to accomplish this purpose, the air hammer 40 is mounted upon a carrier 48 provided at its rearward portion with a pair of rollers 49 and 50 with mating rollers on the opposite side. These rollers travel in an arcuate slot 51 and 52 respectively formed in theheavy sheet plate members 31 of the tool holder frame. The arcuate slots or guideways 51 and 52 have their center on the center of the finished bead of the tube T. As the tool holder turns or rotates, the air hammer is progressively carried across the tool holder along the guideways thus provided.

The mechanism for changing the angular relation of the air hammer to the axis of rotation of the tool holder is best illustrated in Figure 3. A stationary gear 53 is mounted on the inner end of the tubular part 26 of the apparatus frame in order to impart rotation to a small gear 54 keyed to a jackshaft 55 carried by one plate 31 of the tool holder frame. A Worm gear 56 on the other end of the jackshaft is in mesh with a Worm wheel 57 keyed to a clutch shaft 58. A clutch member 59 on the other end of the clutch shaft is splined thereto and slidable longitudinally in order to engage an idler clutch member 60 which is pinned to a pinion 61 in mesh with an arcuate rack 62 secured to the back of the carrier 48. The position of the parts illustrated in Figure 3 is near the finish of a tube beading operation. A clutch disengaging roller 63 is mounted on the lower end of the carrier 48 so as to engage the inner inclined surface 64 of the clutch member 49 and force the clutch teeth of the member out of engagement with the idler clutch member 60. As soon as this action occurs, an elongated tension coil spring 65 connected at one end to a pin 66 on the frame of the tool holder and to a pin 67 on the carrier 48 at the other end will return the carrier to its starting position illustrated in Figure 2. Two such springs are provided, one on either side of the tool holder, and each passes over a stationary pin 71 near one side of the frame adjacent the starting position-of the carrier. Each spring is a loop type of coiled spring which can be replaced on the apparatus should it lose its tension or break under operation. In the process of returning the carrier to its initial or starting position, a second engaging roller 68 secured to the upper end of the carrier will engage an opposite sloping surface 69 on the clutch member 59 and throw the clutch teeth back into engagement. Thus, upon return of the carrier to its initial position with the beading tool member at approximately a 15 angle to the inside of the tube, the apparatus is properly in condition to start beading another tube. The splined clutch member 59 is provided with a frictional connection to the clutch shaft 58 so that it will not longitudinally slide thereon except under the action of the engaging or disengaging

rollers

68 and 63 respectively. The release of the clutch and the return of the carrier to its initial position is an indication to the operator that the beading operation on that tube is completed. He may then remove the pilot 36 from the end of the tube and swing the machine over to the next'tube fora subsequent beading operation.

As previously described, the apparatus may be supported on an overhead hoist connected into the eye 8 which is substantially over the center of gravity of the apparatus. It is thus quite easy for even an unskilled operator to align the tool holder axis of rotation so that it will be coincident with the axis of the tube. Sideways alignment is easy to judge by eye whereas the position of the outer end of the apparatus vertically is more difficult. In order to aid the operator, a bubble tube '70 is mounted on the frame adjacent the handle so that by merely observing the tube the operator can tell whether he should lower or raise the apparatus after he has placed the pilot into the open end of a tube.

We claim:

1. A tube beading apparatus, comprising: a supporting member; tool holding means rotatably mounted on the member; a beading tool carrier movable in the tool holding means along an arcuate path extending across the axis of rotation of the tool holding means; a beading tool mounted on the carrier and having an outer tube engaging portion adapted to form a bead on the tube progressively about the tube periphery; means for rotating said tool holding means and means for concurrently moving said carrier in its arcuate path to change the angle of approach of the tool to the tube including a rack secured to the carrier, a driving pinion carried by the tool holding means and a stationary gear on said supporting member arranged to rotate the pinion upon rotation of the tool holding means.

2. A boiler tube beading machine, comprising: a supporting frame having a tubular hub; a tool holder including a bearing portion mounted on the hub to permit rotation of the holder relative to the frame; motor means mounted on the frame in driving relation with said tool holder; a guide member on the forward end of the holder for aligning the machine with a tube to be beaded; a beading tool mounted in the tool holder in position to direct tube beading hammer blows on a tube; a carrier supporting said tool and movable across the tool holder in an arcuate path having its center at the center of the tube head to be formed; drive means for moving said carrier and beading tool in said arcuate path in timed relation to rotation of the tool holder during a tube beading operation, said drive means including clutch means engageable at a position of beginning and disengageable at the end of travel of said carrier during said tube beading operation, and yieldable means for returning said carrier to said beginning position in said path after a tube beading operation to position the beading tool for a subsequent tube beading operation.

3. A tube beading apparatus as specified in claim 2 in which a stationary gear is mounted on said supporting frame and a drive train is connected between said gear and a rack on said beading tool carrier to progressively move the tool carrier across the tool holder and change the relative approach angle of the beading tool to the tube being beaded.

4. A tube beading machine as specified in claim 2 in which the beading tool comprises an air hammer equipped with a tube bead engaging member having a line of action extending across the axis of rotation of the tool holder, said tool carrier being arranged to move said line of action in a plane passing through said axis of rotation.

5. An air driven boiler tube beading machine, comprising: a supporting frame having a tubular hub and air supply means with manual controls; a tool holder rotatably mounted on said hub and having a forwardly extending portion for insertion in a tube for aligning the rotatable holder with the tube axis; an air hammer beading tool and a carrier therefor movably mounted in said tool holder, said holder having means forming an arcuate guideway extending radially across the axis of rotation of the holder with a center adjacent said forwardly extending portion, said carrier being mounted in the guideway for moving the air hammer radially relative to said axis of rotation to swing the beading tool from the inside to the outside of the tube bead to be formed; an air motor on the supporting frame in driving relation with the tool holder; a stationary gear on the frame and a gear train carried by the tool holder operatively connecting the heading tool carrier and stationary gear to cause movement of the carrier in the guideway upon rotation of the tool holder; means connecting the beading hammer with one said air supply; and means connecting the air motor with another said air supply so that the beading tool may concurrently move about a tube end and swing radially over the tube end to form a tube bead.

6. A tube beading apparatus, comprising: a supporting base; rotatable tool holding means mounted on the base; a beading tool carrier supported entirely by and movable in the tool holding means and having a beading tool mounted therein; guide means on the tool holding means having an arcuate guideway portion extending across the axis of rotation of said tool holding means, said guideway having its center located laterally of said axis of rotation and generally on the center of the bead to be formed on said tube, said carrier being movably mounted in said guideway portion for movement progressively therealong during rotation of the tool holding means; means for rotating said tool holding means and means for concurrently moving the tool carrier over said arcuate guideway portion to change the angular line of action of the tool carrier to the tube being beaded.

7. A tube beading apparatus, comprising: a supporting base; rotatable tool holding means mounted on the base; a beading tool carrier supported entirely by and movable in the tool holding means and having a beading tool mounted entirely on said carrier; means forming an arcuate guideway on said tool holding means, said guideway extending across the axis of rotation of the tool holding means and having its center spaced laterally of said axis of rotation and generally on the center of the bead to be formed on said tube, said carrier being mounted in said guideway for movement therealong and for receiving said beading tool extending forwardly therefrom providing a line of action extending across said axis of rotation when the carrier is in one extreme of the guideway and entirely to one side of said axis when the carrier is in the other extreme of the guideway; means for rotating the tool holding means and means for concurrently moving said tool carrier from said one extreme to said other extreme of said guideway.

References Cited in the file of this patent UNITED STATES PATENTS 286,569 Nugent Oct. 9, 1883 720,052 McKibben Feb. 10, 1903 1,006,934 Grady Oct. 24, 1911 1,162,871 Morris Dec. 7, 1915 1,499,003 Coleman June 24, 1924 1,759,196 Jackson May 20, 1930 FOREIGN PATENTS 809,863 France Dec. 2, 1935