US3810497A

US3810497A - Apparatus for bending rods

Info

Publication number: US3810497A
Application number: US00290939A
Authority: US
Inventors: J Werner
Original assignee: Banner Welder Inc
Current assignee: Banner Welder Inc
Priority date: 1972-09-25
Filing date: 1972-09-25
Publication date: 1974-05-14
Anticipated expiration: 1991-05-14

Abstract

A rod for forming a glow plug is fed between two grooved rollers one of which is rotatable around the other to make a 90* bend in the rod. The rod is then fed to an arcuate die groove of small radius, the groove being carried by a two part die. The bent portion of the rod is clamped in front of the arcuate die groove and a grooved roller is swung orbitally 270* around the arcuate die groove to force the unbent portions of the rod into and around the arcuate die groove, thereby forming a 270* arcuate bend of small radius. The two parts of the die are then separated and the bent rod is removed therefrom.

Description

ttes e 191 Fuchs l/l02 Werner May 14, 1,974

[54] APPARATUS on BENDING nous Prima Examiner-Lowell A. Larson I cut r: ames 0. Werner Greendale, W18. l M o J Attorney, Agent, or Fzrm-Arthur L. Morsell, Jr. [73] Assignee: Banner Welder, Inc., Milwaukee,

[57 ABSTRACT [22] filed: Sept" 1972 A rod for forming a glow plug is fed between two [2l] Appl. No.: 290,939 grooved rollers one of which is rotatable around the other to make a bend in the rod. The rod is then fed to an arcuate die groove of small radius, the 2% F' 'C /71 R i g3 groove being carried by a two part die. The bent porl 92 I g tion of the rod is clamped in front of the arcuate die I 7 f';}' f 5 groove and a grooved roller is swung orbitally 270 around the arcuatedie groove to force the unbent 56 R f d portions of the rod into and around the arcuate die l e erences groove, thereby forminga 270 arcuate bend of small UNITED STATES PATENTS radius. The two parts of the die are then separated and 3,126,036 3/1964 Kent 140/104 the bent rod is removed therefrom. l,526,7l6 2/l925 Neunherz 140/104 1,630,064 5/1927 21 Claims, 10 Drawing Figures SHEET 2 BF 2 APPARATUS FOR BENIDING RODS BACKGROUND OF THE INVENTION This invention relates in general to apparatus for bending rods, and more particularly to apparatus for forming arcuate bends of small radius to form glow plugs. Bending apparatus has been designed in the past for forming arcuate bends of relatively large radius in elongated rods such as metal conduits for electrical conductors or the like. But such bending apparatus has proven to be unworkable when applied to bends of small radius in rods formed of certain types of material, particularly in applications that require relatively close tolerances. One example of such an application arises in connection with the manufacture of glow plugs for automobile carburetors. These are small electrical resistance heaters which are mounted adjacent to the choke butterfly valve in automobile carburetors to raise the temperature of the entering air in cold weather and thereby to prevent the automatic choke from sticking. In one example of this application, a rodshaped electrical heater element 0.0915 inches in outside diameter ismounted within an elongated hollow sleeve which is 0.192 inches in outside diameter and 3 inches long. The heater element and hollow sleeve are both made of steel and are insulated from one another by an insulating sleeve that fits between them. In one model of the heater, a single 270 bend of.0.26 inch radius must be made in the heater rod. In another'model, an additional 90 bend of 0.19 inch radius must be made. The tolerance requirements for the radii of both bends is i 0.01 inches and both bends must be made on a mass production basis.

SUMMARY OF THE INVENTION A die having an arcuate die groove of small radius therein is mounted on a frame and a grooved roller is mounted on the frame in operative relationship with the die. The roller is movable around the die. Means is provided for feeding an elongated rod between the grooves of the die and the roller and for holding a portion of the 'rod stationary. Means is also provided for rotating the roller around the die to force other portions of the elongated rod into the arcuate die groove, thereby forming an arcuate bend of small radius in the rod.

DESCRIPTION or THE DRAWINGS FIG. 1 is a longitudinal sectional view of one illustrative embodiment of the invention taken along the line l1 of FIG. 2;

FIG. 2 is a plan view taken along the line 2-2 of FIG.

FIG. 8 is a detail cross-sectional view of the arcuately grooved die and grooved roller of a second embodiment of the invention;

FIG. 9 is a fragmentary detail view of the set of bending rollers for making the bend; and

FIG. 10 is a fragmentary elevational view showing the guide for the bent rod during its movement from the first station to the second station.

DESCRIPTION OFTHE PREFERRED EMBODIMENT Although this invention is concerned with making arcuat e bends of small radius, the preferred embodiment comprises apparatus for making such bends in an elec trical heater rod to form the same into a glow plug heater for automobile carburetors. FIG. 3 shows one illustrative electrical heater rod 10 that is utilized in connection with the preferred embodiment of this invention. In this particular embodiment, a rod-shaped electrical heater element 12 which is 0.0915 inches in outside diameter is mounted within a hollow sleeve 14 which is 0.192 inches in outside diameter and 3 inches long. The heater element 12 and hollow sleeve 14 are both made of steel and are insulated from each other by an insulating sleeve that fits between them, such insulation being preferably formed of silicone resin. In one model of the heater, a single 270 bend of 0.265

inch radius is made. In another model, a 90 bend of 0.19 inch radius is additionally made at one end of the length of material. The tolerance requirements for the radius of both bends is t 0.01 inches and both bends must be made on a mass production basis.

FIGS. 1, 2, 5, and 6 show one illustrative embodiment of the invention for making both a 90 bend and a 270 bend in the rod 10 on a mass production basis. Referring to FIG. 1, a magazine 16 for holding a plurality of the heater rods 10 is mounted on top of a table 18. A pair of

grooved die rollers

20 and 22 are mounted adjacent to each other and adjacent to the surface of table 118 in front of magazine 16. The groove of each roller is semi-circular in cross'section. The upper die roller 20 is journalled about a pintle 24 that is suitably supported transversely of frame members 26. The lower die roller 22 is journalled between the outer ends of two arms 28. The inner ends of the arms 28 are pivoted on the axis of pintle 24. The die roller 22 is free to rotate about its axis and can also be orbitally moved through a 90 degree are about die roller 20 as indicated by the dashed lines in FIG. 1. The latter movement is achieved by a fluid pressure actuated cylinder 30 whoseram rod 32v is connected by links 34 with the arms 28, the connection between the links 34 and arms being rigid to provide a bell crank arrangement (see FIG. 9). The other end of cylinder 30 is attached through trunnions 36 to a bracket 38 which is attached to a frame member 40;

Both die

rollers

20 and 22 are grooved to receive the. heater rod 10 for the purpose of making a 90 degree bend in the same. The heater rods 10 are fed one at a time between the

die rollers

20 and 22 by a second fluid pressure actuated cylinder 42 which is supported on a frame member 44 and which has a relatively long ram rod 46 that extends through a guide 47 and alines with an end of the lowermost heater rod 10 under the magazine 16. The ram rod 46 makes two forward strokes: a first stroke to feed the heater rod 10 between the two

die rollers

20 and 22, where it receives a 90, and a second stroke to feed the bent heater rod forward to the next bending station, as will be described later.

When the heater rod is fed between die rollers and 22, they are positioned one above the other as shown by the solid lines in FIG. 1. Cylinder then makes a forward stroke to move the die roller 22 to the position shown by dashed lines in FIG. 1, thereby swinging die roller 22 around die roller 20 and making a 90 bend in the heater rod 10. Cylinder 30 then retracts and the bent heater rod 10 is fed forward by cylinder 42 and ram rod 46 to the next bending station.

The next bending station comprises a divided cylindrical die having an upper die portion 48 and a lower die portion 50. An arcuate die groove 52 which is dimensioned to receive the heater rods 10 is formed around the die

portions

48 and 50 over their line of meeting. The radius of die groove 52 is equal to the desired radius of bend which in this particular example is 0.26 inches. The die groove 52 can, however, be dimensioned for smaller or larger bend radii if desired.

Half of the arcuate die groove 52 is below and half above the line of meeting of die

portions

48 and 50. The lower die portion 50 is formed on the end of a shaft 52 which is supported transversely of the surface of table 18. A sleeve 54 having an enlarged head 56 is journalled around the shaft 52 and is supported by suitable frame elements. A die roller 58 having a groove 60 is rotatably mounted on head 56 in operative relationship with the arcuate die groove 52 for receiving the rod member 10 and bending the same as a result of orbital movement of the roller 58 around the die

members

48 and 50. Such movement of roller 58 is accomplished by means of a third fluid pressure actuated cylinder 62 which pushes a rack 64 across a pinion 66 which is attached to sleeve 54. The rotation of sleeve 54 and its head 56 causes the desired orbital movement of die roller 58.

The upper die member 48 is suspended below a platform 68 which is slideably mounted for upward and downward movement upon supporting rods 70. Suitable means such as a fluid pressure actuated cylinder 71 is used to move the upper die member 48 upward and downward. The reason for this movement is to separate the arcuate die groove 52 and therebypermit the bent rod 10 to be removed therefrom. Since, in the preferred embodiment, the rod 10 is bent in a 270 arc around the groove 52, it would not be possible to remove the rod member without separating the die members. This is true for all cases in which the angle of the bend exceeds 180.

Means is also necessary to hold the forward portion of the rod member 10 stationary while the 270 bend is being made. This is accomplished by a clamp 72 which is mounted upon a pivoted arm 74'. A fluid pressure actuated cylinder 76 moves a ram rod 78 which is pivotally attached to arm 74 for moving the clamp 72. When the ram rod 78 is extended, it moves the clamp 72 to the clamping position shown by solid lines in FIG. 1, and when ram rod 78 is retracted, it moves the clamp 72 away from the end of rod 10 to release it for movement.

In this particular embodiment of the invention, there is a tendency for the end of the 270 degree bend to tion where theendofrod 1 0 is located after the 270 degree bend has been made. The ram 80 is moved by the fluid pressure actuated cylinder 84 so as to strike the end of rod 10 and put a permanent bend therein which overcomes the tendency to spring back.

The following steps are taken in forming the 270 bend in the rod 10:

l. a rod 10 with a bend therein is fed between roller 58 and die

members

48 and 50 by fluid pressure actuated cylinder 42;

2. upper die member 48 is moved downwardly by fluid pressure actuated cylinder 71 into operative relationship with lower die member 50 so as to bring the halves of arcuate die groove 52 together;

3. clamp member 72 is swung into position by fluid pressure actuated cylinder 76;

4. roller 58 is orbitally moved 270 around die member 50 by fluid pressure actuated cylinder 62, thereby forcing the unbent portions of rod 10 into the arcuate die groove 52 and forming a 270 bend in rod 10;

5. roller 58 is returned to its initial position;

6. ram 80 is forced against the end of rod 10 by fluid pressure actuated cylinder 84 and is then retracted;

7. clamp member 72 is swung away from rod 10 by fluid pressure actuated cylinder 76;

8. die member 48 is raised by fluid pressure actuated cylinder 71 so as to separate the halves of arcuate die groove 52; and

9. the bent rod member 10 is removed from the lower half of arcuate die groove 52, preferably by a blast of compressed air or some other suitable automatic removal means.

The above-noted steps are repeated continuously on a mass-production basis to mass produce glow plug heaters such as illustrated in FIG. 7 which have a 90 bend therein and also a 270 bend. The timing and control means for actuating the fluid pressure actuated cylinders in the desired sequence is not illustrated as any suitable prior art means can be used toperform this well-known function. The same, is true of the timing and control means for the fluid pressure actuated cylinders used in making the 90 bend in rod members 10. The formation of the 90 bends is carried out simultaneously with the formation of the 270 bends and the two processes are synchronized in the timing and control means by well-known prior art means.

As the rod with the upwardly-bent end is moved from its position between the rollers 20-22 toward the die station 48-50, it is necessary to have guiding means for maintaining the bent end upright during such movement. This is shown in FIG. 10 where there is a bracket 91 having an overhanging head 92 with a slot 93 for guiding the upwardly-bent end of the rod 10. The horizontal portion of the rod 10 is suitably guided in the groove 94 as shown in FIG. 10.

A second embodiment of the invention which is adapted to make the 270 bend but not the 90 bend is illustrated in FIG. 8. This embodiment is the same as the above-described embodiment in most respects and therefore the reference numerals used in FIG. 8 are, for the most part, the same as those used in the other figures. The like numbered parts are identical in both embodiments. The only difference relates to the means for clamping the rod 10 while it is being bent through the 270 arc. In the previously described embodiment, a

movable clamp 72 is used. In the embodiment of FIG. 8, an upper clamp block 86 which has a lower recess 88 clamps the leading end of a rod in position in a groove 89 of a lower nest and holds it in position against movement while the arcuate bend is being made. The clamp block 86 can be attached to frame part 90 or to any suitable means for moving the block 86 into and out of clamping relationship with the end of rod 10.

From the foregoing description it will be clear that this invention provides novelapparatus for making arcuate bends of small radius in rods. And although this invention has been described in connection with two illustrative embodiments thereof, it should be understood that this invention is not limited to the disclosed embodiments since modifications can be made in the disclosed structure without changing its principles of operation. For example, the fluid pressure actuated devices could be replaced by electromagnetically actuated devices if desired without altering the principles of operation. These and other modifications of the disclosed structure will be apparent to those skilled in the art and this invention includes all modifications falling within the scope of the following claims.

What I claim is: r

1. Apparatus for forming an arcuate bend of small radius in a rod, said apparatus comprising a frame, a die mounted on said frame, said die having an arcuate die groove of small radius therearound, a roller having a die groove supported on said frame adjacent to said die and supported for orbital movement around the arcuate die groove of said die, means for axially feeding a .rod having lead and trailing portions into position between the die grooves of said roller and die, means in advance of said die and roller intermittently movable to a position to engage the lead portion of said rod to hold said rod stationary, means for causing said orbital movement of said roller around said die to force trailing portions of said elongated rod into said arcuate die groove of the die, thereby forming an arcuate bend of small radius 'in said rod, and means for releasing said rod holding means after each of said roller movements.

2. The apparatus defined in claim 1 wherein said frame includes a table having a relatively flat surface over which the rod is fed axially and having an opening therethrough, a shaft supported in alignment with said opening, said die being carried on the upper end of said shaft and positioned in the opening in said table, there being a sleeve journalled within said opening around said shaft, said roller being rotatably mounted in an eccentric position on the end of said sleeve adjacent to said die, and means coupled to said sleeve for rotating the same, thereby causing said roller to move around said die to form an arcuate bend of small radius in said elongated rod.

3. Apparatus for forming an arcuate bend of small radius in a rod, said apparatus comprising a frame with a table, and said table having an opening, a lower die member mounted on said frame and projecting through said opening, an upper die member mounted on said frame above said first die member, one of said die membersbeing movable into and out of operative relationship with the other die member, means for causing said die movement, said lower and upper die members having die grooves in their adjacent ends which are shaped and dimensioned to cooperate in forming an arcuate die groove of small radius when they are in operative relationship with each other, the die groove portion of said lower die member being immediately above the top surface of said table, means for feeding a rod along said table into operative relationship with said die grooves, means in advance of said die members for holding a lead portion of said fed rod stationary, means for bending trailing portions of said rod around and into said cooperating die grooves to form an arcuate bend of small radius therein, and means for moving one of said die members out of operative relationship with the other a sufficient distance to separate said die groove portions and permit removal of the bent rod.

4. The apparatus defined in claim 3 wherein said means for bending said rod into said cooperating die grooves comprises a grooved roller which is mounted for orbital movement around said first and second die members, and the groove insaid grooved roller being aligned with said cooperating die grooves.

5. The apparatus defined in claim 4 wherein the cross-sectional shape of said cooperating die grooves and the cross-sectional shape of the groove in said roller match the cross-sectional shape of said elongated rod.

6. The apparatus defined in claim 4 wherein there is a shaft mounted within said table opening, said lower die member being mounted on the upper end of 'said shaft near the surface of said table, a sleeve journalled within said opening around said shaft, said grooved roller being journalled in an eccentric position on the upper end of said sleeve adjacent to said lower die member, and means for rotating said sleeve to cause orbital movement of said grooved roller around said lower die member.

7. The apparatus defined in claim 6 and further comprising means for mounting said upper die member above and in alignment with said lower die member, and means for moving said upper die member toward and away from said first die member.

8. The apparatus defined in claim 6 wherein said sleeve has an enlarged head at its upper end and wherein said grooved roller is eccentrically journalled on said head.

9. The apparatus defined in claim 6 wherein said grooved roller is movable around said first die member through an arc of more than I 10. Apparatus for forming an arcuate bend of small radius in a rod, said apparatus comprising a frame, a die mounted on said frame, said die having an arcuate die groove of small radius therearound, a roller having a die groove supported on said frame adjacent to said die and supported for orbital movement around the arcuate die groove of said die, means for axially feeding a rod having a lead portion and a trailing portion with an end into position between the die grooves of said roller and said die, means for holding a portion of said rod stationary, means for causing said orbital movement of said roller around said die to force trailing portions of said elongated rod into said arcuate die groove of the die, thereby forming an arcuate bend of small radius in said rod, ram means mounted for reciprocable move ment into engagement with the end of said trailing portion of the rod after it has been arcuately bent and while it is around the die for overcoming any tendency of said end to spring back, and means for operating said ram means. i

l 1. Apparatus for forming two arcuate bends of small radius in a rod, said apparatus comprising a frame, a first grooved roller of small radius journalled to said frame, a second grooved roller of small radius journalled to said frame in operative relationship with said first grooved roller, said second roller being movable in a curved path around said first roller, the grooves of said first and second rollers being dimensioned to receive said elongated rod, means for feeding said elongated rod between said first and second grooved rollers within the grooves thereof, means for moving said second grooved roller in a curved path around said first grooved roller to force said elongated rod into the groove of said first grooved roller, thereby forming a first arcuate bend of small radius in said rod, a first die member mounted on said frame, a second die member mounted on said frame opposite said first die member, one of said die members being movable into and out of operative relationship with the other die member, means for causing said die movement, said first and second die members having die grooves which are shaped and dimensioned to cooperate in forming an arcuate die groove of small radius when they are in operative relationship with each other, means for feeding the bent rod from between said first and second rollers into operative relationship with the cooperating grooves of said die, means for holding the bent portion of said elongated rod stationary, and means for bending the unbent portions of said elongated rod around and into said cooperating die grooves to form a second arcuate bend of small radius in said rod.

12. The apparatus defined in claim 11 wherein said means for bending said elongated rod into said cooperating die grooves comprises a third grooved roller which is mounted for orbital movement around said first and second die members, and the groove in said third grooved roller being aligned with said cooperating die grooves.

13. The apparatus defined in claim 12 wherein said frame includes a table having a relatively fiat surface, said first and second grooved rollers being mounted with their axes parallel to the surface of said table and said third grooved roller being mounted with its axis transverse to the surface of said table.

14. The apparatus defined in claim 13 wherein said table has an opening therethrough, a shaft having an end positioned within said opening, said first die member being attached to the upper end of said shaft near the surface of said table, a sleeve joumalled within said opening around said shaft, said third grooved roller being eccentrically joumalled to the upper end of said sleeve adjacent to said first die member, and means for rotating said sleeve to cause orbital movement of said third grooved roller around said first die member.

15. The apparatus defined in claim 14 and further comprising means for mounting said second die member above said first die member and means for moving said second die member toward and away from said first die member.

16. The apparatus defined in claim 15 wherein said sleeve has an enlarged head at its upper end and wherein said grooved roller is eccentrically joumalled on said head.

17. The apparatus defined in claim 16 wherein said second grooved roller is orbitally movable about said first grooved roller through an arc of less than and wherein said third roller is orbitally movable around said first die through an arc of greater than 180.

18. Apparatus for forming two bends of small radius in a rod of the type which has opposite ends, said apparatus comprising a firstbending station, means at said first bending station for bending one end portion of a rod at an angle with respect to the remainder of the rod to provide a first bend, a second bending station, means for moving rods one after another to said bending stations in sequence, means at said second bending station for bending another portion of. the rod to provide an eye formation therein with the plane of the eye formation extending transversely of the plane of the first bend, and means for holding the portion of the rod with the first bend stationary while said eye is being formed.

19. Apparatus as claimed in claim 18 in which the first bend is at right angles to the remainder of the rod, and in which said first bend projects upwardly while said eye is being formed in a horizontal plane'.

20. Apparatus as claimed in claim 18 in which the portion of the rod with the first bend is moved to and held in a position in advance of said second bending station while said eye is being formed in a trailing portion of the rod.

21. Apparatus as claimed in claim 18 in which the holding means for the first bend comprises a pivoted lever, a clamp carried by said lever for movement into and out of engagement with said first bend of the rod while the latter is in position at said second station, and means for swinging said lever to move the clamp into and out of clamping engagement.

Claims

1. Apparatus for forming an arcuate bend of small radius in a rod, said apparatus comprising a frame, a die mounted on said frame, said die having an arcuate die groove of small radius therearound, a roller having A die groove supported on said frame adjacent to said die and supported for orbital movement around the arcuate die groove of said die, means for axially feeding a rod having lead and trailing portions into position between the die grooves of said roller and die, means in advance of said die and roller intermittently movable to a position to engage the lead portion of said rod to hold said rod stationary, means for causing said orbital movement of said roller around said die to force trailing portions of said elongated rod into said arcuate die groove of the die, thereby forming an arcuate bend of small radius in said rod, and means for releasing said rod holding means after each of said roller movements.

3. Apparatus for forming an arcuate bend of small radius in a rod, said apparatus comprising a frame with a table, and said table having an opening, a lower die member mounted on said frame and projecting through said opening, an upper die member mounted on said frame above said first die member, one of said die members being movable into and out of operative relationship with the other die member, means for causing said die movement, said lower and upper die members having die grooves in their adjacent ends which are shaped and dimensioned to cooperate in forming an arcuate die groove of small radius when they are in operative relationship with each other, the die groove portion of said lower die member being immediately above the top surface of said table, means for feeding a rod along said table into operative relationship with said die grooves, means in advance of said die members for holding a lead portion of said fed rod stationary, means for bending trailing portions of said rod around and into said cooperating die grooves to form an arcuate bend of small radius therein, and means for moving one of said die members out of operative relationship with the other a sufficient distance to separate said die groove portions and permit removal of the bent rod.

4. The apparatus defined in claim 3 wherein said means for bending said rod into said cooperating die grooves comprises a grooved roller which is mounted for orbital movement around said first and second die members, and the groove in said grooved roller being aligned with said cooperating die grooves.

6. The apparatus defined in claim 4 wherein there is a shaft mounted within said table opening, said lower die member being mounted on the upper end of said shaft near the surface of said table, a sleeve journalled within said opening around said shaft, said grooved roller being journalled in an eccentric position on the upper end of said sleeve adjacent to said lower die member, and means for rotating said sleeve to cause orbital movement of said grooved roller around said lower die member.

9. The apparatus defined in claim 6 wherein said grooved roller is movable around said first die member through an arc of more than 180*.

10. Apparatus for forming an arcuate bend of small radius in a rod, said apparatus comprising a frame, a die mounted on said frame, said die having an arcuate die groove of small radius therearound, a roller having a die groove supported on said frame adjacent to said die and supported for orbital movement around the arcuate die groove of said die, means for axially feeding a rod having a lead portion and a trailing portion with an end into position between the die grooves of said roller and said die, means for holding a portion of said rod stationary, means for causing said orbital movement of said roller around said die to force trailing portions of said elongated rod into said arcuate die groove of the die, thereby forming an arcuate bend of small radius in said rod, ram means mounted for reciprocable movement into engagement with the end of said trailing portion of the rod after it has been arcuately bent and while it is around the die for overcoming any tendency of said end to spring back, and means for operating said ram means.

11. Apparatus for forming two arcuate bends of small radius in a rod, said apparatus comprising a frame, a first grooved roller of small radius journalled to said frame, a second grooved roller of small radius journalled to said frame in operative relationship with said first grooved roller, said second roller being movable in a curved path around said first roller, the grooves of said first and second rollers being dimensioned to receive said elongated rod, means for feeding said elongated rod between said first and second grooved rollers within the grooves thereof, means for moving said second grooved roller in a curved path around said first grooved roller to force said elongated rod into the groove of said first grooved roller, thereby forming a first arcuate bend of small radius in said rod, a first die member mounted on said frame, a second die member mounted on said frame opposite said first die member, one of said die members being movable into and out of operative relationship with the other die member, means for causing said die movement, said first and second die members having die grooves which are shaped and dimensioned to cooperate in forming an arcuate die groove of small radius when they are in operative relationship with each other, means for feeding the bent rod from between said first and second rollers into operative relationship with the cooperating grooves of said die, means for holding the bent portion of said elongated rod stationary, and means for bending the unbent portions of said elongated rod around and into said cooperating die grooves to form a second arcuate bend of small radius in said rod.

13. The apparatus defined in claim 12 wherein said frame includes a table having a relatively flat surface, said first and second grooved rollers being mounted with their axes parallel to the surface of said table and said third grooved roller being mounted with its axis transverse to the surface of said table.

14. The apparatus defined in claim 13 wherein said table has an opening therethrough, a shaft having an end positioned within said opening, said first die member being attached to the upper end of said shaft near the surface of said table, a sleeve journalled within said opening around said shaft, said third grooved roller being eccentrically journalled to the upper end of said sleeve adjacent to said first die member, and means for rotating said sleeve to cause orbital movement of said third grooved roller around said first die member.

16. The apparatus defined in claim 15 wherein said sleeve has an enlarged head at its upper end and wherein said grooved roller is eccentrically journalled on said head.

17. The apparatus defined in claim 16 wherein said second grooved roller is orbitally movable about said first grooved roller through an arc of less than 180* and wherein said third roller is orbitally movable around said first die through an arc of greater than 180*.

18. Apparatus for forming two bends of small radius in a rod of the type which has opposite ends, said apparatus comprising a first bending station, means at said first bending station for bending one end portion of a rod at an angle with respect to the remainder of the rod to provide a first bend, a second bending station, means for moving rods one after another to said bending stations in sequence, means at said second bending station for bending another portion of the rod to provide an eye formation therein with the plane of the eye formation extending transversely of the plane of the first bend, and means for holding the portion of the rod with the first bend stationary while said eye is being formed.

19. Apparatus as claimed in claim 18 in which the first bend is at right angles to the remainder of the rod, and in which said first bend projects upwardly while said eye is being formed in a horizontal plane.