US2086736A

US2086736A - Rod bending machine

Info

Publication number: US2086736A
Application number: US61701A
Authority: US
Inventors: Palmer Robert Kendrick
Original assignee: Individual
Current assignee: Individual
Priority date: 1936-01-31
Filing date: 1936-01-31
Publication date: 1937-07-13
Anticipated expiration: 1954-07-13

Description

Jul 13, 1937. K PALMER 2,086,736

ROD BENDING MACHINE Filed Jan. 51, 1956 2 Sheets-Sheet 2.

lumen-but R.K.PHL[I1E.R

Eltlr-urneg Patented July 13, 1937 PATENT @FFECE BOD EEENDING MACHIINE Robert Kendrick Palmer, Hamilton, Untario, Canada Application January 31, 1936, Serial No. 61,701

15 Claims.

My invention relates to improvements in rod bending machines, and the object of the invention is to devise means for simultaneously effecting a plurality of bends in a straight rod.

A further object is to devise means for facilitating the starting of the bending operation.

A still further object is to construct a machine which, by the changing of the elements of the bending mechanism, will produce a bent rod in which the bends are differently disposed and may be either uniform or variable.

My machine is particularly applicable for form ing from straight rods Z or zig-zag skeleton webs for structural shapes or for forming reinforcing rods for concrete constructions, it being understood that the web so formed has all its bends disposed in the same plane.

With the above and other objects in View which will hereinafter appear as the specification proceeds, my invention consists, in its preferred embodiment, of the construction and arrangement all as hereinafter more particularly described and illustrated in the accompanying drawings in which:

Fig. 1 represents a plan View, shortened intermediately, of my machine.

Fig. 2 is a side elevational view thereof.

Fig. 3 is an enlarged vertical cross-sectional view taken on the line 3-3 (Fig. 1).

Fig. 4 is an enlarged vertical sectional View of the driving gears of my machine taken on the line 3-4 (Fig. 1).

Fig. 5 is a. fragmentary View similar to Fig. 1 showing an alternative arrangement of bending elements for a bent rod in which the bends taper in height from one end to the other, and

Fig. 6 is a fragmentary view similar to Fig. 1 showing the elements of the machine in the position they assume when the rod is completely bent.

Like characters of reference indicate corresponding parts in the different views.

My machine comprises a bed 5 preferably supported on a concrete base 2, a bracket 3 on the bed having a plate t secured thereto. Opposed

guides

5, 5 extend longitudinally and centrally of the bed i in which a driving block 6 is adapted to slide, such driving block being secured to one end of a longitudinal screw l. The screw '1 is carried in a correspondingly threaded gear 8 journalled in a split housing 83 secured to the plate 4. The gear 8 meshes with a worm it on a shaft I! also journalled in the housing 9 and which may be driven by any suitable power means. The housing 9 is adapted to be filled with heavy oil (fill. 153-213) or grease and sealing rings l2 therefor may be disposed on the shaft ll between each end of the worm ii! and the adjacent face of the housing 9. The threading of the screw l is preferably of the square type.

A stationary block it is secured in the guides 5 at the end of the bed l remote from the housing t, and a plurality of blocks H are adapted to slide in the guides 5 between the blocks 6 and it. Each sliding block ill has a vertically disposed hollow fulcrum bearing l8 secured therein on which crossed links it and 28 of a lazy tongs mechanism are pivoted intermediately of their length. Each link it is interposed between the links as which are double and the free ends of the double links are pivoted to the corresponding free ends of the single links. The end links 2| of the lazy tongs mechanism are half links and are pivoted on

fulcrum pins

22, 22 secured in theblocks ii and i6 respectively.

A pin it is rotatably secured in the bore of each fulcrum bearing l8, and has an enlarged head 2 projecting above the bearing in which is a notch 25 to receive the rod 26 to be bent. The heads 2 of the pins are received in central vertical orifices ill in rod clamps 28 which are provided with longitudinal rod-receiving grooves 29 of the same cross-section as the notches 25 in the pin heads, which grooves and notches are adapted to register with each other, the clamps being secured against rotation on the pins by, for example, keys Sil, and against vertical displacement therefrom by set-screws 3|.

Links 32 are pivoted intermediately of their length on the fulcrum bearings i8 above the bars l9 and 2t and their free ends are pivoted together on pins 33, the end links 34 of such link system being half links pivoting on the fulcrum pins 22 in the blocks 6 and I6. The links 32 and 3-5 are of such length that adjacent links are always disposed at an angle to each other even when the lazy tongs mechanism is extended to the limits of its travel. A bend starting hook 35 is secured to each of the pins 33 to overlie the bars 32, one end of which is adapted to underlie the bar 26 to be bent when the latter is positioned in the clamps 23 and has a rod engaging upstanding projection 36 thereon, and the other end of which is provided with a longitudinal slot 31 in which one of the pivot pins 38 for the levers l9 and 2G is adapted to slide.

A longitudinal notch 39 is also provided in the lower face of each clamp 28 which is adapted to receive a cable to running longitudinally of the machine through orifices 41 in the head 24 of each pin 23 and anchored at each end in thecorresponding pin head, which serves to align the clamps 28 when the lazy tongs mechanism is extended.

The operation of the device is as follows: By rotating the shaft H in the proper direction the worm iii thereon causes the gear 8 to rotate, and since such gear is held against axial displacement in the housing 9 the screw 1' draws the driving block in the guides 5 away from the fixed block it which results in the lazy tongs mechanism being opened up until the cable ii] has rotated the clamps 22 into such position that all the rod receiving grooves 29 therein are in alignment. lazy tongs mechanism the

links

32 and 34 move the starting hooks 35 toward the longitudinal centre line of the lazy tongs. The rod 26 to be bent is then inserted into the grooves 39 and the shaft ll is'rotated in the opposite direction to cause the screw 'l'to move the driving block 6 towards the fixed block it. When this occurs, the closing up of the

link system

32, 34 causes the starting hooks 35 to move away from the longitudinal centre line of the lazy tongs and the projections 3t engage the rod 25 and start the bending operation which is then continued by the closing up of the lazy tongs mechanism. It will be observed that, due to their angular relationship, the

links

32, 34 carrying the starting hooks swing faster than the links l9, 2a of the lazy tongs mechanism, but slower than the rod bends once the bends are started and since the starting hooks are disposed alternately on opposite sides of the lazy tongs mechanism a rod bent alternately one way and then the other is fabricated. It will also be evident that the moving relationship between the starting hooks, the rod clamps and the rods is always such that there is complete clearance between these parts.

It will be obvious'from the above description and the drawings that by altering the length of the links 69 and 20 and the length of the rod clamps 28 the rod instead of being bent to have uniform bends through its length may be so bent that these bends taper from one end to the other (Fig. 5), from each end towards the centre, or in any other desired arrangement.

An advantage of my improved machine is that a large number of bends may be made in a rod therewith simultaneously, so that the machinewill have a very high output of bent rods.

Yet another advantage is that, by providing a number or" interchangeable rod clamps, lazytong links and bend starting links of different dimensions for the machine, a number of different types of bent rods having different arrangements of the bends may be produced in the one machine.

A further advantage is that the position of each bend in a rod bent in my machine is always exactly located by the rod clamps, so that all bent rods produced in the machine with one set of clamps are exact duplicates of each other and the bends of each rod lie wholly in one plane. In addition, substantially the whole length .of each part of a rod between bends is supported by a rod clamp during bending of a rod, resulting in such parts being straight in the finished bent rod. 7

What I claim as my invention is:

1. A rod bending machine comprising a plurality of rotatable rod engaging elements, means for slidably positioning the rod engaging ele- During such movement of the ments in alignment and in spaced relation to receive a rod to be bent, means for engaging the rod between each pair of rotatable rod engaging elements for effecting initial bending of the rod, and means for simultaneously decreasing I the spacing between the rotatable rod engaging elements in the means for slidably positioning the latter to complete the bending of the rod.

2. A rod bending machine comprising a lazy tongs, means for opening'and closing the lazy tongs, rotatable rod engaging elements positioned at the central intersections of the bars of the lazy tongs, means for aligning the rod engaging elements during opening of the lazy tongs to receive a rod to be bent and means coacting with the lazy tongs for engaging the rod between each pair of rotatable rod engaging elements and adapted to effect initial bending of the rod, the closing of the lazy tongs serving to complete the bending of the rod.

3. A rod bending machine as claimed in claim 2 wherein the means for opening and closing the lazy tongs comprises means in the machine for positioning one end of the lazy tongs, a screw secured to the other end of the lazy tongs, a rotatable element threaded on said screw and secured against axial displacement in the machine, and means for rotating the rotatable element. 7

i. A rod bending machine as claimed in claim 2 wherein the rod aligning means comprises a flexible member interconnecting said rotatable rod engaging elements.

5. A rod bending machine as claimed in claim 2 wherein the means coacting with the lazy tongs for engaging the rod comprises a plurality. of levers each pivoted on the lazy tongs at a central intersection of a pair of bars thereof, a pin pivotally connecting one end of each lever to one end of the adjacent lever and a rod engaging member carried on each pin, the length of the levers being such that the rod engaging members are disposed alternately on opposite sides of the longitudinal centre line of the lazy tongs when the latter is open.

6. A rod bending machine comprising a bed, a guideway thereon, a plurality of blocks slidably secured in the guideway, a fulcrum on each block, a pair of cross-ed bars pivoted intermediately of their ends on each fulcrum and pivotally connected together to form a lazy tongs, means for opening and closing the lazy'tongs, a rod clamp rotatably positioned on each fulcrum, means for aligning the rod clamps during opening of the lazy tongs to receive a rod to be bent, a plurality of levers pivoted intermediately of their ends one on each fulcrum, a pin pivotally connecting one end of each lever to one end of the adjacent lever, and a bend starting hook carried on each pin, said levers being of such length that the bend starting hooks are disposed alternately on opposite sides of thelongitudinal centre line of the lazy tongs when the latter is open.

7. A rod bending machine as claimed in claim 6 wherein the means for opening and closing the lazy tongs comprises a member secured in the guideway to which one end of the lazy tongs is pivotally secured, a member slidable in the guideway to which the other end of the lazy tongs is pivotally secured, and means for moving the member slidably in the guideway away from and toward the member secured in the guideway.

8. A rod bending machine as claimed in claim 6 wherein the means for opening and closing the lazy tongs comprises a member secured in the guideway to which .one end of the lazy tongs is pivotally secured, a member slidable in the guideway to which the other end of the lazy tongs is pivotally secured, a threaded rod secured to the member slidable in the guideway, a rotatable member thread-ed on the rod, means on the bed for rotatably supporting the rotatable member against axial displacement in the machine, and means for rotating the rotatable member.

9. A rod bending machine as claimed in claim 6 wherein each rod clamp comprises a block having a rod receiving groove therein.

10. A rod bending machine as claimed in claim 6 wherein each rod clamp comprises a block having a rod receiving groove therein and the rod clamp aligning means comprises a flexible member secured at one end to the fulcrum adjacent one end of the lazy tongs and at the other end to the fulcrum adjacent the other end of the lazy tongs and means on each rod clamp for engaging the flexible member.

11. A rod bending machine as claimed in claim 6 wherein each bend starting hook comprises a plate, a hooked projection thereon adapted to underlie and engage the rod to be bent, and means on the plate and engaging the lazy tongs for maintaining the hook at right angles to the axis of extension of the lazy-tongs during open ing and closing of the lazy tongs.

12. A red bending machine comprising a bed, a gui'deway thereon, a plurality of blocks slidable in the guideway, a hollow fulcrum bearing projecting from each block, a pair of levers journall-ed on each fulcrum bearing in X formation, a pin connecting one free extremity of each lever to the opposite extremity of the adjacent lever, a fixed block in one end of the guideway, a pin secured in the block, a pair of links pivotally connecting the pin with the free extremities of the adjacent pair of crossed levers, a driving block slidable in the other end of the guideway, a pin secured in the driving block, a pair of links pivotally connecting the pin with the free extremities of the adjacent pair of crossed levers, a threaded rod secured to the driving block, a worm gear threaded on the rod, a housing secured to the bed and in which the gear is journalled against radial displacement, a worm journalled in the housing and meshing with the gear, a pin rotatably secured in each fulcrum bearing, a rod clamp mounted on each pin, means for aligning the rod clamps to receive a rod to be bent during outward movement of the driving block in the guideway, a bend starting bar journalled intermediately of its ends on each fulcrum bearing, a pin pivotally connecting one extremity of each bend starting bar to one extremity of the adjacent bar, a link pivotally connecting the pin in the fixed block to the free end of the adjacent bend starting bar, a link pivotally connecting the pin in the driving block to the free end of the adjacent starting bar, the lengths of the bend starting bars being such that each is disposed at an angle to its neighbour when the driving block is positioned at the outer limit of its movement in the guideway, and a bend starting hook pivoted on each pivot pin of the bend starting bars adapted to engage the rod to be bent at a point between each adjacent pair of rod clamps, the bend starting hooks being directed alternately towards opposite sides of the guideway.

13. In a rod bending machine as claimed in claim 12, a head on the pin rotatably secured in each fulcrum bearing and having a rod receiving transverse groove therein, a rod clamp comprising a block having a pin head receiving orifice therein and a rod receiving groove adapted to register with the groove in the pin head, and means for preventing relative rotation of the pin head and the clamp.

14. A rod bending machine as claimed in claim 12 wherein the means for aligning the rod clamps comprises a cable secured at one end to the pin rotatably secured in the flucrum bearing adjacent the fixed block and at the other end to the pin rotatably secured in the flucrum bearing adjacent the driving block and passing through orifices in the intervening pins and through grooves in the rod clamps registering with such orifices.

15. A rod bending machine as {claimed [in claim 12 wherein each bend starting hook comprises a plate having an orifice for receiving one of the said pins pivotally connecting a pair of starting bars and having a slot therein adapted to slidably receive the pin on which the adjacent levers of the first mentioned lever system are pivoted.

ROBERT KENDRICK PALMER.