US2829698A

US2829698A - Rotating tube-straightening machine

Info

Publication number: US2829698A
Application number: US505998A
Authority: US
Inventors: Robert M Stikeleather
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-05-04
Filing date: 1955-05-04
Publication date: 1958-04-08
Anticipated expiration: 1975-04-08

Description

April 8, 1958 R M. s-rlKELEATHlI-:R 2,829,593

ROTATING TUBE-STRAIGHTENING MACHINE Filed May 4, 1955 5 Sheets-Sheet 2 5 Sheets-Sheet 3 R. M. STIKELEATHER ROTATING TUBE-STRAIGHTENING vMACHINE ,April 8, 1958` Filed May 4, 1955 April 8, 1958 R. M. snm-:LEATHER 2,829,698

ROTATING TUBE-STRAIGHTENING MACHINE 5 Sheets-Sheet 4 Filed May 4, 1955 April 8, 1958 R. M. snm-:LEATHER 2,829,698

ROTATING TUBE-STRAIGHTENING MACHINE 5 Sheets-Sheet 5 Filed May 4, 1.955

162082223024: 30.581455 Msf'efeag dfndey United States Patent O ROTATING TUBE-STRAIGHTENING MACHINE Robert M. Stikeleather, Holbrook, Mass.

Application May 4, 1955, Serial No. 505,998

4 Claims. (Cl. 153-100) This invention relates to tube straightening machines, and relates more particularly to machines for straightening tubes for supply to finning machines.

A widely used type of heat exchanger for heating or cooling air or other gases is a hollow metal tube through which a heat exchange liquid is circulated, and having a metal ribbon wound spirally on its external surface. Such ribbons on such tubes are usually referred to as tins My copending application, Serial No. 464,388, led October 24, 1954, now Patent No. 2,799,389, granted July 16, 1957 discloses a nning machine for winding such ribbons spirally on tubes to -form fins.

The tubes on which such ribbons are wound may be copper tubes of, say outside diameter, and are usually supplied in 20 lengths by a tube manufacturer. Such short tubes not only involve intermittent operation of a iinning machine at short intervals with increased handling and operating expense, but frequently the lengths of finned tubes which are desired are not 20' lengths but may be longer or shorter than 20 lengths. If longer, tubes must be spliced together. If shorter, cut olf portions are wasted.

Tubing manufacturers supply coiled tubes in boxes for use by plumbers and others, the lengths of such coiled tubes being 450. This invention makes use of such coiled .tubes to supply long straight tubing to a nning machine, reducing the cost of the tubing, and reducing the cost of iinning ythe tubing.

In one embodiment of this invention, the top of a box containing a coiled tube is removed, and the upper end of the tube is passed over a relatively large diameter reel having a horizontal rotary axis. The relatively small radius curvature of the coiled tube is removed by the reel which also changes the direction of the tube and lines it up with a caterpillar type conveyor which moves the tube into a tube straightener comprising a rotary tapered roll which ilexes the Itube back and forth for` straightening and hardening it. A second caterpillar type conveyor takes the straightened and hardened tubing from the straightener, and supplies it into a straight, long pipe or xtrough which stores a long length of straight tubing. Two or more of such storage pipes are provided closely together and parallel to each other.` A iinning machine is located alongside the tube straightener, and draws a straight tube from one of the storage pipes, and finsit while the straightening machine supplies another length of straight tubing into another storage pipe. An embodiment of this invention in actual operation straightens and stores a 450 length of straight tubing which enables a finning machine to operate continuously for forty minutes, the nned tubing, while moving, being cut olf at the outlet side of the finning machine to provide the desired lengths of nned tubing.

An object of this invention is to provide long straight tubes for use in a firming machine.

tubing for use in a nning machine.

. reel.

,. Nice Another object of this invention is to provide an improved tube straightening machine.

This invention will now be described with reference to the annexed drawings, of which:

Fig. 1 is a diagrammatic plan view of an embodiment of the invention in which a straightening machine straightens tubing taken from a coil, previously straightened tubing being shown supplied to a inning machine;

Fig. 2 is a side elevation of a reel arranged to remove a large part of the curl from coiled tubing, and to supply the partially straightened tubing to a straightening machine;

Fig. 3 is a plan view looking downwardly upon Fig. 2;

Fig. 4 is a side elevation of the tube straightening ma'- chine;

Fig 5 is an end View of one of the conveyors of Fig. 4;

Fig. 6 is an enlarged side View, partially in section, of the rolls of Fig. 4, and their supports;

Fig. 7 is a plan view of Fig. 6;

Fig. 8 is a sectional view along the line 8-8 0f Fig. 7;

Fig. 9 is a sectional view along the line 9--9 of Fig. 6;

Fig. 10 is a sectional view along the line 10-10 of Fig. 11

Fig. 1l is a fractional side elevation of one end of one of the conveyors of Ithe straightening machine;

Fig. 12 is an end view of one of the sprockets of Fig. ll, and

Fig. 13 is a side elevation, partially in section, of another embodiment of a tube straightener that can be used to replace the one shown by Figs. 6-8. i

Referring first to Figs. 2 and 3, coiled tubing 15 is supplied by a tubing manufacturer in a. rectangular wooden box 16. The top of the box is removed, and the box is placed under a tube guide consisting of a lower ring 17 joined by tubular legs to a smaller upper ring 19, therings being concentric with vertical axis. A relatively large diameter reel 20 has a horizontally extending shaft supported in bearings 21 on structural pipes 22 which are supported by vertically extending structural pipes 23 which are connected by a brace 24 to a frame 25. A roller 26 is supported on the pipes 22 for guiding tubing from the coil 15 onto the reel. A roller 27 is supported on the pipes 22 diametrically opposite the roller 26 for causing the tubing to follow the outline of the A third roller 28 is supported by the pipe 23 under and spaced from the reel, and serves to guide the tubing leaving the reel into the guides 30 on the frame 25.

The lower ring 17 of the tube guide above the box 16 is supported by the pipe 31 from the frame 25..

A tube straightening machine consisting of an incom- `ing caterpillar type conveyor 35, a tube straightener 36, and an outgoing caterpillar type conveyor 37 are supported on the `frame 25, with the inlet end of the conveyor` 35 located adjacent the tube guides 30.

The

conveyors

35 and 37 are similar and each has an upper endless track consisting of spaced apart metal blocks 38 connected together by links 39, and meshed with sprockets 40 at the opposite ends of the track, teeth 41 on the sprockets entering the spaces between blocks 38. The blocks 38 in their outer surfaces have recesses 42 curved in circular arcs to fit `the tubing 15. Each yof the

conveyors

35 and 37 also has a lower track consisting of the blocks 45 connected together by links 46 and meshed with teeth 48 on sprockets 47 at the oppositeends of the track. The blocks 45 in their outer surfaces have recesses 49 curved in circular arcs to fit the tubing 15.

An fOilite bearing plate 50 contacts the inner surfaces of the blocks 38 in the lower pass of each upper track, and asimilar plate 51 contacts the inner surfaces of the blocks 45 in the upper pass of each lower track, below and in alignment with the plate 50. Bolts 52 pass through the plates 50 and 51, and have coiled springs 53 around their lower portions between nuts 54 and the lower plate, causing the blocks in the lower pass of the upper track and the blocks in the upper pass of the lower track to gripthe tubing with their recessed outer surfaces.

The shaft 55 of the inner sprocket 47 of the conveyor 37 is driven through sprockets and a chain 56 by a speed reducing lgear box 57 which is driven by an electric motor 59. The shaft 60 of the inner sprocket 40 of the conveyor 37 is driven by a gear 61 meshed with a gear 62 on the shaft 55y whereby the upper and lower tracks of the conveyor 37 are driven together. The inner sprocket 47 of the conveyor 35 has a shaft 63 with a sprocket driven by a chain 65 which is meshed with a sprocket 66 on the shaft 55.v The inner sprocket 40 of the conveyor 35 has a shaft 67 with a gear thereon which is not illus trated but which is similar to the gear 61, which is meshed with a gear which is not illustrated but which is similar to gear 62, on the shaft 63 of the inner sprocket 47 of the conveyor 35, whereby the upper and lower tracks of the conveyor 35 are driven together. The conveyor 35 is driven from the conveyor 37 by the chain 65.

The tube straightener 36 which is located between

thel conveyors

35 and 37, comprises a pair of end members 70 to which the side plates 90 are attached by machine screws 91. The plates 90 have recessed or grooved portions shaped to provide with the inner surfaces of the members 70, passages in which blocks 74 are slidably positioned. The shaft 7S of a tapered roll 76 is journalled in the blocks 74 which are attached to straps 81 by machine screws 82, spacers 83 being placed between the blocks and straps. The straps 81 extend across the plates 90 and are attached thereto by the machine screws 80. Blocks 71 are also slidably positioned in the passages formcd by grooves in the plates 90 and the inner surfaces of the members 70, and have journalled therein the shaft 72 of a cylindrical roll 73. The blocks 71 are attached to straps 77 by machine screws 78, spacers 79 being placed between the straps 77 and blocks 71. The straps 77 extend across and are attached to the plates 90 by the machine screws 83. The plates 90 are attached to the end members 70 by machine screws 91.

The outer portions 85 of the members 70 are formed as cylindrical bearing surfaces within the bearings S6, one of the end portions 85 having a pulley 87 attached thereto which is driven through a belt 88 by an electric motor 89.

The spacers 83 are thicker than the spacers 79 and thereby space the shaft 75 of the tapered roll 76 nearer the rotary axis of the straightener 36 than the shaft 72 of the cylindrical roll 73. The

rolls

76 and 73 are spaced apart at their nearest portions a distance slightly less than the diameter of 'a tube 15 to be straightened. The tapered roll 76 is so located that it exes a tube 15 back and forth as it is rotated around the axis of the tube, the tube being squeezed between the

rolls

73 and 76 and being, therefore, hardened. Spacers having different thicknesses are provided for varying the degree of tube exing and squeezing, and also for the handling of tubes having different diameters.

A pair of relatively small plates 97 are bolted by machine screws 98 to the mid portions of the outer surfaces of the plates 90, and have portions 92 which extend through openings 93 in the plates 90 and form journals for the shafts 95 of the tube backing-up rolls 94 which contact opposite sides of the tube 15 in its flexed position as shown by Figs. 6-8.

A pair of tubes 96 extend around the tube 15 just short of where it enters and leaves the spaces between the

rolls

73 and 76, and have bell-mouth inner portions 84 which are shaped to follow the curvature of the tube 15 where it starts to bend through being exed by the roll 76, and where it starts to straighten on leaving the

rolls

73 and 76. The bell-mouths support the tube and prevent it from buckling.

As the tube is flexed back and forth, all curl and other irregularities are removed so that the tube is straight when it enters the outgoing conveyor 37.

A straight tube on leaving the conveyor 37 enters one of the straight storage pipes or troughs 99 shown by Fig. 1. While the straightening machine is supplying a straight tube into one of the pipes or troughs 99, a previously straightened tube is being drawn from the other storage pipe or trough 99 by a nning machine 100 which is located alongside of and close to the tube straightening machine. The pipes or troughs 99 are on opposite sides of and slightly spaced from a line extend ing midway between the fnning and straightening ma chines. The slight temporary bend given the tube asA it enters and leaves a storage pipe is of no consequencel as the spring action of the hardened tube causes such: temporary bends to straighten out.

Fig. 13 illustrates another tube exing and hardening device which can be used instead of the one shown by Figs. 6-8. In this embodiment, instead of using bell mouthed tubes to follow the curvature of a tube 15 at the start and end of its flexing, tapered rolls which are shaped and positioned to follow such curvature, and oppositely positioned cylindrical rolls are used. Another difference is that the cylindrical roll opposite the tapered flexing roll is omitted. Advantages of this embodiment are that there is less sliding friction, and additional tube hardening.

The tapered roll 76 for flexing the tube 15 is retained but its co-operating cylindrical roll 73 is omitted. The bell mouths 84 are also omitted, and are replaced by tapered rolls 101 which are shaped and located to contact the tube where its exing starts and ends as described in the foregoing in connection with the bell mouths 84. The tapered rolls 101 have opposite them cylindrical rolls 102 which contact the tube 15 opposite where it is contacted by the rolls 101. The adjacent closest surfaces of the

rolls

101 and 102 are closer together than the diameter of a tube 15 whereby the tube is squeezed between these rolls and thereby hardened.

The inner ends of the shafts of the rolls 101 are journalled in blocks 103 and their outer ends are journalled in blocks 105 which blocks are slidably fitted in guideways in plates V104. The shaft of the tapered roll 76 is journalled in blocks 105A which arealso slidably tted in guideways in the plates 104. The inner ends of the shafts of the cylindrical rolls 102 are journalled in blocks 106 which are slidably tted in other guideways in the plates 104, and their outer ends are journalled in blocks 107 which are slidably fitted in guideways formed by the inner surfaces of the end members 108 and recesses or grooves in the plates 104. The blocks in which the shafts of the rolls are journalled are held in place by machine screws 109 extending through straps 110 into plates 104. One of the end members 108 has a bearing portion 112 of reduced diameter in bearing 113, and has a pulley 114 on its outer end, this pulley being driven by the belt 88 of Fig. 4.

The tube straightening and hardening structure of Fig. 13 was found to reduce the sliding friction of a tube to be straightened and hardened, and the use of the

tubes

101 and 102 instead of the bell mouths provided additional squeezing and hardening of the tube.

Summary of operation In operation, the

conveyors

35 and 37 draw a tube 15 from the coil in the box 16, through the guides 17 and 19, over the reel 20, and through the guides 30 into the conveyor 35 so that the tube is properly lined-up for movement through the straightening machine. The flexing of the tube in the straightening device removes the curl from the tube and otherwise straightens it. The tube is hardened by the squeezing so that it has sufficient spring tension to cause it to .remain straight during further handling.

The tinning machine 100 removes a previously straightened tube 15 from another storage pipe or trough 99 during the straightening of another tube, and places a spiral fin 115 thereon.

The invention is not, of course, limited to the exact apparatus and arrangement of apparatus illustrated and described herein since modiiications thereof may be suggested by those skilled in the art, without departure from the essence of the invention.

What is claimed is:

l. A tube straightening machine comprising a support having similar, aligned, cylindrical passages at its tube entering and leaving ends for guiding a tube into and out of said support, said support having an opening between and aligned with said passages, the axes of said opening and passages being in alignment, means for rotating said support about said axes, means for moving a tube to be straightened through said passages and opening, a tube flexing roll in said opening, said roll being journalled for rotation in said support about the axis of said roll and about the axis of said opening, said axis of said roll being spaced from and parallel to said axis of said opening, said roll having a tapered surface, the surface of said roll at its largest diameter extending a distance towards said axis of said opening less than the radius of said passages whereby the tube to be straightened is tlexed by the rotation of said roll about said axis of said opening during the rotation of said support, and a pair of tube backing-up rolls spaced apart a distance equal to the diameter of said passages and journalled for rotation in said support about said axis of said opening, said backing-up rolls having axes equally spaced from said axis of said exing roll and extending parallel to said axis of said ilexing roll, a straight line extending through said axes of said opening and said flexing roll being perpendicular to a straight line extending through said axes of said backing-up rolls.

2. A tube straightening machine as claimed in claim 1 in which a pair of spaced-apart hardening rolls is provided in said opening between said tube entering end of said support and said exing roll, said hardening rolls being journalled for rotation in said support` about said axis of said opening, one of said hardening rolls being tapered, the spacing between the closest adjacent surfaces of said hardening rolls being smaller than said diameter of said passages.

3. A tube straightening machine as claimed in claim 2 in which a second pair of hardening rolls is provided in said opening between said tube leaving end of said support and said ilexing roll, said rolls of said second pair being journalled for rotation in said support. about said axis of said opening, one of said rolls of said second pair being tapered, the spacing between the closest adjacent surfaces of said rolls of said second pair being smaller than said diameter of said passages.

4. A tube straightening machine as claimed in claim 1 in which a pair of spaced-apart hardening rolls is provided in said opening between said tube leaving end of said support and said exing roll, said hardening rolls being journalled for rotation in said support about said axis of said opening, one of said hardening rolls being tapered, the spacing between the closest adjacent surfaces of said hardening rolls being smaller than said diameter of said passages.

References Cited in the file of this patent UNITED STATES PATENTS' 518,403 Haas Apr. 17, 1894 602,931 Batey Apr. 26, 1898 1,538,325 Higgins May 19, 1925 1,936,679 Leech Nov. 28, 1933