EP0287494A2 - Wire processing machine - Google Patents

Abstract

Wire processing machine consisting of:

• a) a feeder mechanism, providing simultaneously:
  • 1.pulling or feeding of wire.
  • 2.straightening of wire
  • 3.torsion to any direction or counter torsion of the wire.
• b) a wire bending system, of adjustable curvature radi­us, two direction bending with moving cutting system mounted on the bending system.

Description

• The invention refers to a machine which process circular section wire, including straightening, two directional bending and cutting. The machine consists of:
  -a system forcing torsion , pulling and steaightening.
  -a bending system capable of bending the wire in two di­rections with adjustable curvutuve radius and mounted cutter, which follows wire while bending and may cut t­he wire in any position.
• Existing machines for wire straightening, bending and c­utting distinguish themselves from the a.m. machine in following:
  -Wire pulling is acheived through two roller pairs, pla­ced exactly across the wire, which press wire inbetween forcin it to pass through straightening rollers, locat­ed ahead pulling rollers.
  This results to a radial deformation of the wire. To p­revent deformation, different rollers with respective grooves should be used for each wire diameter.
  This should cost a lot of money and time during adjust­ment to new wire diameters.
• Existing machines use for two directional bending three pins. Two of them position wire and are fixed and the t­hird one is the bending pin, which bends wire around the one or the other pin for left or right bends respective­ly. This is a disadvantage as when bending pin is on the right, and a left bend is required, the pin has to pass under the wire to go left. This makes existing machines complicated. Cutting is made by a cutter located either ahead bending head, causing the wire to move backwards to be cut this making the machine slow and complicated, or after bending head, where a flying cutter has to app­roach for cutting. In this case time and higher costs a­re required.
• In my machine there is no need for the two roller pairs of the wire. Pulling is supplied by the lower mechanica­lly driven straightening rollers.
• This way, pulling is distributed to several rollers avo­iding thus surface deformation of the wire, and straigh­tening becomes easier. Moreover wire feeding is easier, as straightening rollers pull wire as soon as it is put in contact to them.
• The upper straightening rollers are not driven directly and they force a slight wire torsion, as it is explained analytically in the following.
• The advantage of the bending system is that only two pi­ns are used for two direction bending. In each bending one acts as the pin around which wire is bent and the o­ther one as the bending pin. For counter bents functions of both pins alternate.
• The on the benter fixed cutter, enables cutting of wire while bender is rotated or directly after bent, without leaving a straight portion if desirable.
  The above mentioned function is explained analytically using figs 1,2,3.
Figure 1.-Nomendature.
• 1.Roller
• 2.Metal circular section rod.
• 3.Theoretical axis of straightened rod (OX).
Function
• We consider any roller(1) of a rod straightening system using rollers, with the straightened rod(2) exactly bel­ow it. The resulting picture is given in Fig.1, where t­he roller is presented dotted.
• This is the casein all static systems for metal, circul­ar section, rod straightening up to now and as tortion is examined on the rod.
• If the roller plane is rotated by an angle(w), around an axis vertical to OX and passing through the roller cent­erpoint, torsion of the straightened and pulled rod is achieved as it is proved theoretically and practically. The rotation of the roller plane, thus deviating from the up to now used through OXpassing plane and the important result achieved through this rotation on the controlled rod torsion build the substance of the here described invention.
• This controlled torsion enables forming of perfect 2 - D shapes and complicated 3-D shapes on automatic rod bending machines.
Analysis of rod torsion.
• Considor that roller (1) is rotated by an angle (w), coun­terclockwise in Fig (1), taking position (1′) and conta­cting rods on points (E1) and (E2).
• Points (E1) and (E2) move both on the with a relocity (u) pulled rod (2) and on the with the vocational speed (V) rotating roller.
• Direction of (V) is constant and tangential to the circles (Π1) and ( Π2) of the roller. If there is no slip between the contacting surfaces, points (E1) and (E2) as belonging to the rod, follow (V). This is possible only if there is a rod torsion, giving a rotational speed of the rod contact points, as indicated in Fig. 1.
• Following rector equation is valid :
      V = u + u _π      (a)
  For small values of angle w we have:
      V = u/cos w = u      (b)
      U_π = u tan w = u. w(RAD) =

  

  u.w (°)      (c)
  Rod centerpoint O is approximately fixed. With (ΔΦ/Δt) the torsion angle of the rod is one second and (d) the rod diameter, we derive :

  

  This means that counterclockwise (w) results to a counter­clockwise torsion of the pulled rod (direction O----X) and inversely.
  The resulting torsion torque (Mt) by each rotating roller is:
  Mt = (Friction) d/2 = T.d = 0,5P. .cos a.d
  Where
      P: The roller pressing force.
      T: Friction force
      a: half roller angle
      µ: friction factor.
  For (n) rollers, the total torsion torque is:
  Mto = 0,5.n.P.µ. cosa.d      (e)
  The required power N for the torsion is
  N=Mto.(Δφ/Δt) (kpm.rad/sec) = Δφ/(75.Δt) (HP)
Figure 2 - Nomendature
• 1. Not adjustable roller with one or more grooves
• 2. Adjustable roller with one or more grooves
• 3. Motor
• 4. Adjustable roller support
• 5. Adjustable roller housing
• 6. Lever
• 7. Common transmission bar
• 8. Piston
• 9. Disk with adjustable pins
• 10. Disk shaft
• 11. Disk shaft housing
• 12. Disk shaft piston
• 13. Disk shaft positioner
• 14. Metal wire
• 15. Adjustable pin
• 16. Wire pulling direction
• 17. Rotation direction of non adjustable roller
• 18. Axis of rotation of roller support (4).
Function 1. Pulling or forwarding of wire
• Wire transportation from pay-off station to the machine is usually described using one of the two words above. The number of the non adjustable rollers (1) as well as of the adjustable ones(2) may be anyone. The numbers of non adjustable and adjustable rollers may be equal to e­ach other or differ by one. The distances between the n­on adjustable rollers and the distances between the adj­ustable ones may be equal to each other or differ from each other. Non adjustable and adjustable rollers may have or may not have grooves. First, metal wire(14) is put between rollers(1)and (2). Trapping of metal wire (14) between non adjustable(1)and adjustable rollers(2) is acheived by moving the laters to the formers. Moveme- is acheived by pistons(12), which stretch out pressing through housing (11) shaft(10), bearing the disks with adjustable pins(9).
• The number of disks(9) is equal to the number of the ad­justable rollers(2).Each disk(9) bears some adjustable pins(15), placed if possible on the corners of a regular polygon.The length of each pin (15) may be adjusted thr­ough a bolt. The pins (15) are grouped. Each group has a pin number, equal to the disks(9) and the pins of every group, belonging one to each disk, lay on the same, thr­ough shaft (10) passing level. The disks (9) are actual­ly normal to the shaft (10), but for visualization purp­oses are drawn , turned by 90° on the drawing level. The disk shaft positioner (13) defines the pin group, which will press the adjustable roller supports(4) through ro­tation of shaft(10).
• Further the pin (15) group, being above the adjustable roller supports(4) presses them forcing them into the spaces between the non adjustable roller(1). Wire (14) is trapped this way and is forced to form a curved line betwwen the adjustable and non adjustable rollers.
• As non adjustable rollers (1) are driven by motor (3) in rotation direction (17) , wire moves towards pulling di­rection(16).Any type of motor may be used , but the hyd­raulic one gives best performance. Roller driving may be also supplied by more than one motors , each motor driv­ ing one group of rollers(1). In Fig.2 , only one motor (3) is presented schematically through a chain of all t­he non adjustable rollers(1). If the rotation direction (17) of motor (3) is reversed wire pulling direction(16) changes.
• For each rod diameter ,eg6.8.10.12.14.16.mm, a group of pins (15) is preset, having preset the lengths of the p­ins to give best pulling and straightening, as it is de­scribed later on. By rotating simultaneously all disks (9) through positioner(13), setting of the feeder is ac­heived very quickly and preciselyfor the wire diameter to be feeded. The end of the approach between rollers is determined by the pistons.(12).
2.Wire straightening.
• The final position of adjustable rollers (2) in respect to the non adjustable rollers(1) guarantees a plastic d­eformation of the wire on the contact points between wi­re and rollers. This deformation differs from roller to roller depending on the setting of the respective pin(15) The elastic comeback of the wire after its plastic defo­rmation is exactly sufficient to give ti the wir a stra­ight form on the level, which is normal to the paper le­vel of the drawing. For full straightening of the wire , a second mechanism is required, similar to the one desc­ribed above. Its rollers should lay in a level normal to the drawing level, and it should be located directly af­ter the first one in a distance not causin plastic defo­rmation to the processed wire.
3. Torsion and counter torsion.
• The adjustable rollers supports(4) may be rotated round the axis of rotation(18), using levers(6) and the common transmission bar(7), driven by the double direction pis­ton (8) to left or to right. The roller support(4) rota­tes in its housing (5) around axis (18) by a small angle to the right or to the left in respect to the drawing l­evel.Due to friction , rotation of rollers(2) around ax­is (18) results to torsional movement of the pulled rod. This achievement is documented in my patent Nr87.0596/t.8 76/s.-191 of April 14th 1987, 00.30am.
• Without power to the piston (8), the adjustable rollers (2) are put, due to the grooves , on the drawing level.
Figure 3.- Nomendature
• 1.Rotating body
• 2.Interchangeable upper part.
• 3.Interchangeable lower part.
• 4.Lower left pin.
• 5.Lower right pin
• 6.Upper left pin
• 7.Upper right pin
• 8.Fixed cutter.
• 9.Moving cutter.
• 10.Housing
• 11.Fixed wire guide
• 12.Motion system of housing(10)along ^Ψ and X directions. (but not Z)
• 13.Interchangeable plate with 2 centers of rotation.
• 14.Cutter transmission piston.
• 15.Piston front sealing ring
• 16.Piston back sealing ring
• 17.Position marker of transmission piston.
• 18.Flexible hydraulic pipe between transmission piston (14) and cutter piston.
• 19.Flexible hydraulic pipe between transmission piston (14) and oil pump.
• 20.Cylinder of transmission piston.
• 21.Metal rod.
• 22.Housing(10). draw-back spring.
• 23.Chain gear.
• 24.Chain.
• 25.Left semicircular housing of plate (13)
• 26.Right semicircular housing of plate(13).
• 27.Trapped oil between transmission piston(14)and oil pi­ston.
• 28.Trapped oil between transmission piston(14) and oil p­ump.
• 29.Draw back spring of transmission piston.
• 30.Motion direction of metal rod.
• 31.Direction of chain(24) first motion.
• 32.Direction of chain (24) second motion.
Function
• Housing (10) remain always , parallel to itself, on level O^ΨX.
• Inside housing (10), the rotating body (1) of the bender may rotate freely , driven by a motor, fixed on body(1), through the chain gear(23) and the chain(24). Certainly, chain motion may have two directions:
  (31) and (32). Mounted on the rotating body(1), is the p­iston which drives the moving cutter(9). The rotating bo­dy(1) ends up at the interchangeable upper part(2) and d­own at the interchangeable lower part(3).
• Parts (2) and (3) are fastened to body(1) by means of be­lts
• The interchangeable upper parts(2) bears: a square openi­ng through which passes the moving cutter (9), the upper left(6) and upper right (7) pins of the cutter (8).
• Pins (6) and (7) locate the fixed cutter (8) at a certain distance from the upper level of (2) and on the other ha­nd, they provide bending of the rod(21) passing between them. The interchangeable lower part (3) bears only the

  

  lower left pin (5) and the lower right pin. (4)
• The draw-back spring (22) keeps housing (10) in such a p­osition that at least of pins (4) or (5) is placed inside the grooves (25) or (26) of plate (13) respectively.
• The distance between the centerpoints of the semicircular grooves(25) and (26), the distance between the centerpoi­nts of the upper pins (6) and (7) are equal to each other Pins (4) and (5), as well as pins (6) and (7) may bear o­uter rings, to prevent their wear. The outer diameter of pins(4) and (5) is equal to the diameter of grooves (25) and (26) respectively. The outer diameter of pins (6) and (7) is equal to the inner diameter of the circles we want to form on the processed rod.
• Metal rod (21) goes through pins (6) and (7) after passi­ng through the fixed wire guide(11).
• If the motor moves chain (24) to direction (31) , then f­ollowing will happen:
• 1.Pin (4) will rotate inside groove(25).
• 2.Pin (5) will move away from groove (26).
• 3.Body(1) will rotate inside housing (10).
• 4.Housing (10) will move respectively inside level OYX.
• 5.Pin (6) rotates around the same axis as pin(4) does.
• 6.PIn (7) will move pressing the rod(21) and bending it as it is shown in in Fig 3.
• Similar things happen, when chain moves in direction (32) The upper part (2) along with (6) , (7) and (8), and the lower part (3) along with (4) and (5) and plate (13) wi­th its grooves (25) and (26), build a series of intercha­ngeable parts, allowing bending of certain sizes of metal rods with certain curvature radii. We mark the possibili­y of forming different diameters with pins (6) and (7). Cutting is acheived by pushing moving cutter (9) to appr­oach fixed cutter (8), as it is usual in all cutters cut­ting through shearing of metalrod. When metal rod is cut, by the upwards moved moving cutter (9), it is launched aw­ay from table's surface, where it rests. Moving cutter is driven by a hydraulic piston, located in the rotating bo­dy. (1). These are one direction pistons . They are push­ed by high pressure oil and they are drawn back by a str­ong spring. Position of moving cutter(9) is of great imp­ortance for a) decreasing the moving cutter stroke in sm­all diameter rods and b) for givving next command to the bending head, directly after cutting.
• As cutter moves along with the bending head, I have found out following movement transmission system from a fixed point to the moving cutter.
• In the flexible high pressure oil pipe(19), from the hyd­raulic pump to the cutter piston, the cylinder of transm­ission piston (20) is inserted. This is a cylinder inside of which piston (14) retrogrades freely, supported again­st the input of the higher pressure oil by a coil(29). There are two sealings for piston (14), (15) and (16).
• The position marker (17) supplies outside information ab­out the position of transmission piston (14).Both result­ing spaces of the flexible pipe, (27) and (28), are fill­ed with oil after removing air.
• This way oil pressure from space (28) is transmitted thr­ough piston (14) to the oil of space (27). The transmiss­ion piston (14) movement, may now be followed by the pos­ition marker (17). Given that oil ia not compressible and piping (18) is melastic , transmission piston movement is related directly to moving cutter piston movement, allow­ing thus full monitoring of the later.

Claims (10)

1. The machine for proc­essing of circular section wire, consisting of straigh­tening system (Fig 2), pulling rollers(Fig 2),upper ro­llers (Fig 2) rotating systemfor upper rollers(Fig2),b­ending head for two direction bending bending(Fig 3),f­lying cutter (Fig 3,9), motor, chain (Fig3,24),plate(F­ig.3,13) and pins (Fig.3,4 and 5) and having following features:
2. 1.Amelioration of static roller mechanisms for straigh­tening of metal circular section rods, through supplyi­ng of rotation driving for the rollers, around an axis normal to OX, thus enabling fully controlled torsion of the, through feeding and pulling , straightened rod (torsional speed and and torsional direction).
   This additional feature of the static roller mechanisms for wire straightening, is of great importance, when this straightening mechanisms are used in automatic be­nding machines , for forming of plane shapes using met­al circular section rods.
   In this case, during the successive bendings, a contin­uous torsion on the rod is required to achieve continu­ous contact between the formed plane shape and the mac­hine table.
   Otherwise almost always, shapes remain open and not pl­ane.
3. 2.Feeder of metal wire processing machines, ensuring s­imultaneously:
   Feeding - torsion of countertorsion on request and str­aightening with fast adjustment to any processed wire diameter.
4. 3.System of disks(9) with pins (15) on shaft(10) with disk shaft positioner (13), enabling fast adjustment of adjustable rollers (2) mounted on supports(4) and hous­ing (5), where driving is supplied by pistons(12)(Fig2)
5. 4.Supports (4) rotating system, with housings (5),leve­rs (6) through common transmission bar and double dire­ ction piston (8), enabling a small rotation of adjusta­ble rollers(2) around axis(18), clockwise, or counterc­lockwise (Fig 2).
6. 5.Compound straightening and pulling system through in­sertion of adjustable rollers(2) in the spaces between the non adjustable rollers(1), where driven are only t­he non adjustable rollers (1).(Fig 2).
7. 6.System of housing (10)moving on the OXY level, with the rotating body (1) inside,driven by a motormounted on it, through chain (24) and chain gear (23), where t­he rotation centerpoint is defined only by the centerp­oints of plate(13)and the pins (4) and (5) (Fig.3).
8. 7.Moving cutter system with rotating body (1),consist­ing of a moving cutter (9), driven by a hydraulic pist­on mounted on body(1), and fixed cutter (8) mounted on body (1) through pins (6) and (7) and part(2). With th­is cutting system, wire cutting is possible in any pos­ition of the bending system.(Fig 3).
9. 8.Series of 3 interchangeable parts A,B,C consisting of following parts:
   A) (2) + (6) + (7) + 8)
   B) (3) + (4) + (5)
   C) (13)
   through which a fast and easy adjusting of bending sys­tem on the desired wire diameter and curvature radius of the bents is achieved (Fig 3)
10. 9.Transmission piston system , of moving cutter(9) from the rotating body(1) to the steady part of the machine consisting of cylinder(20), free piston(14) with two se­aling rings (15) and (16) as well as the draw-back pis­ton (29) and the position marker (17).(fig.3).

Images