US1762234A - Tube bender - Google Patents

Description

c. N. MATTHEWS TUBE BENDER June 10, 1930.

2 Sheets-Sheet 1 Filed Dec. 27, 1928 A TTOR NE YS.

June 10. 1930. c. N. MATTHEWS TUBE BENDER 2 Sheets-Sheet 2 Filed Dec. 27. 1928 v INVENTOR.

. Char/es A! l'fazkh ems BY 77W 77- a ATTORNEYS.

Patented June l O, 1930 NI ED S A oHA eL smMArrHnws, or Los AivenLns; camromvr i i Application filed December 27,1928. Serial at. 328,750.

g This invention relates to a bending machine designed to bend bars, tubes and the llke in a curve. Heretofore; it has been common practice to provide-a curved former 5 having-a grooved seat for a tube or bar, a

lever pivotally mounted and carrying a bending roller. The tube or. bar to be bent is clamped in position againstthe former between it and the bending-roller and the 10 lever swung to bend the bar or tube against the seat. This requires considerable force to be exerted to swing the lever, Furthermore, each machine has' been limited to onev slze of bar or tube and one radius of curvature for the bend. H

The objects of this invention are to pro-' vide a bending machine qhaving' power amplification means to cause travel of the bending roller over the'bar or. tube. seat; to bending machine having a former hable and:

providea and roller arranged to. be'detac interchangeable .with .other formers and rollers to accommodatethe machine to diflen;

invention illustrated in the accompanying.

drawings, in which I, I

Fig. 1 is a plan view of 'a' complete sembly, the upper cover plate of the ratchet handle being removed to betterillustrate the ratchet structure; Fig. 2 is a front view as seen looking in the direction of the arrow 2 in Fig. 1; Fig. in thedirection of the arrow 3 in Fig. 1; Fig. 4 is a-view similar-to Fig. 3 showing another size of former-and itsqcoacting roller, parts being shown inc-section to better illustrate the 'invention; Fig. 5 -.is a section as seen on the line 5 5 ofFig; 1; and Fig.

6 is afragmentary section in plan showing the reversible ratchet.

Referringwith more particularily to the drawings, A indicates a semi-circularbase plate arranged with suitable bolt holesl nd 3--is a rear ;view looking serving tor attaching thebase "pljate to'a bench or table in horizontal position. The base plate has bolted thereto a semi-circular rack B whichcomprises a segmental gear." Detachablybolted to the rack B is'a former markedC in Figs. ,1, 2, 3 and 5 and c in- 4. Pivotally secured to'the former is a lever v indicated generally by D. Journalled on the;

lever is a bending roller to coact-with the former seat marked E in Figsl 2 and'3 ande. in Fig.- 4. A

having astubshaft to receive, a ratchet han-J dle G. 1 I

v The base plate A corresponds 'in fcurvature. to' the rack. It hasv a flat-lower face" 10 so as to lie flush againstsurface to isa hub portion 11', and

the table or ,bench' :be'bolted. There qwhich it-may; I

;a rim; portion '12- with an intermediate cut-awayqportion 18. The upper surface; of the rim and hub are in alinement. 1

the heads bench. A

Bolt holes with-sockets for of bolts to be sunk therein are baseplate in position upon a peripheral1-recess15 serves as a track for a roller as is later described,

' Rack B joined by. holes I regi has a hubtportionl6 and a rim 17 web 18. Inthe web are bolt stering with corresponding bolt Gear 'teeth'are provided on-the periphery of the rim; On.

recess 20 serving as a track for a roller. the rack in former C; Figs. 1-, 2, 21 a'nd a r the 1under face of the rim 1s a "is shown bolted to l 3 and 5 .;,;This former has a hub im 22fjoined by a web-2'3. Bosses or projections; are provided adjacent, the

rim as indicated by and sockets for; the.

the former to the rackfth'ere bemg ing alined tapped bolt former c shown in 24 which have bolt holes heads of bolts25 secur holes the rack. The Fig. 'is of like construction; but smaller in curvature and there are bolt holes withthe respects, former 0 is as to dlmensions.

former is in the. rack which will register the former 0 In. other like former C except In the periphery of the a semi-circular, groove 26 serving oltholes in bolts 14 mounted therein for V V .base to receive. bolts 19 for sewise secured to shaft 38 is a pinion 39 mesh- 7 as a seat for the tube to be bent. An opening is provided in the hub 21 concentric with the periphery of the rack B for receiving a bolt 27 serving as a spindle for the bending lever D.

Referring particularly to Figs. 1, 2 and 3, the lever D comprises an arm 28 mounted uponspindle 27. Secured to the end of the arm 28 is a cross member 29 having a guide track 30 for the ratchet handle Gr. Bolted to the under side of the rail 30 is an L shape arm 31, there being a brace 32 to add to the stability. J ournalled upon a trunnion extending from the end of arm 31 is a roller '33 riding in way 15 of the base plate. A

roller 34 is journalled on a spindle mounted on top of arm 31 and travels in way 20. Slidably mounted upon arm 28 is a block 35 carrying rollers 36 which rideupon the upper surface of the former. Block 35 is adjustable as to position so that it may be accommodated to the particular former used, it being held in adjusted position by set screws 37. J ournalled in arms 28 and 31 is a shaft 38 having a squared end38 to receive ratchet handle G. Keyed or othering with the teeth on rack B. Obviously, by turning the pinion, the lever A will be caused to swing.

To prevent retrograde movement of the lever, a pawl mechanism is provided consisting of a bushing 40 upon which is rotatably mounted a ring 41. Ring 41 has diametrically opposed cars 42* and 42 and a lug 43. Pawls 44* and 44 are pivotally mounted upon the arm 31, being secured to the corresponding ears 42 and 42 by links 45* and 45" which slidably pass through holes in the ears, the links being provided with abutment heads. Compression springs 46 and 46 embrace the links and act between the ears and pawls. The construction is such that the ring 41 may be positioned so as to .ma'intain one pawl in engagement with the teeth on the rack and the other pawl retracted as shown in Fig. 6 or the positions of the pawls may be reversed by turning the ring. Turning of the ring is accomplished by means of a connecting link 47 secured to lug 43 at one end and at the other end to a pin on a disk 48. Disk 48 has a spindle journalled in arm 31 to which a wing 49 is afiixed so that by turning the disk, the pawl mechanism may be disposed to prevent movement of the lever either in one direction or the other.

The ratchet handle comprises a handle portion 50 with a head 51 in which is journalled a ratchet wheel 52. The ratchet wheel 52 has asquare opening to detachabl-y receive the end .38 of the pinion shaft. A pawl 53 is provided for engaging the teeth 9 the ratchet wheel and a manually operable post 54 provides for releasing the pawl from the ratchet. The particular details of the ratchet handle forms no part of the present invention and may be varied in its details.

In Figs. 1, 2 and 3 a bending roller E is shown journalled upon shaft 38, there being a suflicient space between the grooves in the bending roller and in the former to accommodate ,a tube. If a smaller former is used as shown in Fig. 4, the lever is demounted and a bar 55 bolted to arm '31. Bar 55 carries a roller 56 which rides upon the upper face of the rack. Suitable holes are provided in the arm 28 and corresponding holes in the bar 55 for receiving a shaft 57 upon which is journalled bending roller 6 to cooperate with the former 0. Obviously, various sizes of formers may be used and bending rollers will be correspondingly mounted between arm 28 and bar 55.

In order to clamp the bar or pipe in position upon the former a clamp comprising jaws 58 and 58 is secured by pins 59 and 59 to the former at the rear. Provision is made for securing the clamp at either side of'the former so that bending may be performed from either end. A corresponding clamp for the smaller former is shown in Fig. 4.

In order to bend a pipe or bar, the latter is inserted 'in the clansip opening and between the bending roller and the former. The ratchet handle is then oscillated, the reversible pawl having been positioned-to prevent retrograde movement. Oscillation of the ratchet handle causes rotation of the pinion and travel of the latter arounduthe rack. This causes the lever to be swung and with it the bending roller so that the tube is pressed against the grooved seat in the former and bent to the desired shape.

What I claim is:

1. A bending machine comprising a peripherally curved rack, said rack having an undercut way, a former detachably see cured to said rack including a peripherially arcuate tube seat concentric with said rack, a bending lever pivotally and detachably secured to said rack and former at the center of their arcs, said lever including ,a yoke arm having rollers journalled thereon and riding in said way, a pinion journalled on said lever and meshing with said rack, means to rotate said pinion to cause said lever to turn, and a bending roller journalled on said lever to coact with said seat.

2. A bending machine comprising a pcripherally arcuate rack, said rack having an undercut way, a former detachably secured to said rack and including a peripherially arcuate tube seat concentric with said former, a bending lever pivotally and detachably secured to said rack and former at the center of their arcs, said leverincluding i'is a yoke arm having rollers journalled thereon $550 and riding in said way, a pinion journall'ed on said lever and meshing with said rack,

means to rotate said pinion to cause said lever to turn, a pawl mounted on said lever and engaging the teeth of said rack toprevent retrograde movement of said lever, and a bending roller journalled on said lever to coact with said seat.

3. A bending machine comprising a peripherally arcuate rack, a former detachably secured to said rack and including a peripherally arcuate tube seat concentric with said rack, a bending lever pivotally and detachably secured to said rack and former at the center of their arcs, a bending roller journalled on said lever to traverse said seat and coact therewith, a pinion journalled on said lever and meshing with said rack, said rack having an undercut way, said lever including ayoke arm having rollers journalled thereon and riding in said Way, said pinion having a shaft provided with a stub end, a ratchet handle on said stub end to rotate said pinion and turn said lever, and

a reversible pawl mechanism mounted on said leverand engaging the teeth of said rack to prevent retrograde movement of said lever.

In witness that I claim the foregoing I have hereunto subscribed my namethis 15th day of December, 1928. p N. MATTHEWS.

CHARLES

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