EP0538763B1

EP0538763B1 - Device for correcting the straightening of iron rods and the like

Info

Publication number: EP0538763B1
Application number: EP92117830A
Authority: EP
Inventors: Simone Rupoli
Original assignee: Schnell SpA
Current assignee: Schnell SpA
Priority date: 1991-10-22
Filing date: 1992-10-19
Publication date: 1996-03-20
Anticipated expiration: 2012-10-19
Also published as: ITBO910386A0; DE69209218D1; DE69209218T2; IT1253217B; ATE135610T1; EP0538763A1; ITBO910386A1; DK0538763T3

Abstract

Device for correcting straightening comprising a rotating unit which is suitable to be actuated, so as to perform angular rotations about the advancement axis of an iron rod, by a first motor element (9), so as to arrange itself on different planes in relation to the correction to be performed. Multiple rollers (11a,11b,11c) are mounted, so that they are co-planar, on the rotating unit, and the iron rod is passed between them. A crank system (17a,17b,17c), which can be actuated by a second motor element (16) supported by the rotating unit, is suitable to simultaneously adjust the mutual distance of the rollers (11a,11b,11c) from the iron rod advancement axis. <IMAGE>

Description

The present invention relates to a device for correcting the straightening of iron rods and the like, in particular for building.
It is known that iron rods used for example to produce shaped rods for reinforced concrete and the like are generally machined from a spool wherein the iron wire is wound in a reel. The machines used to produce said shaped rods usually have a unit for feeding and straightening the iron rod and a bending chuck which subjects a front portion of the rod to an appropriate series of bending actions, so as to obtain the required shape; the bending is combined with the operation for the transverse cutting of said portion of the rod.
In order to perform the straightening operation, devices which pass the iron rod between a plurality of variously orientated and sized rollers are currently widespread.
However, the straightening operation is performed by said devices uniformly along the entire wire, whereas said wire generally does not have uniform characteristics. Therefore the iron rod, when it exits from the straightening step, can have a more or less significant twist which is orientated unpredictably on different planes and is variously orientated. This obviously compromises the optimum execution of shaped rods.
Devices using such rollers are described in the previous documents US-A-4 719 781 and JP-A-59-150636.
A further example of a straightening device having the features set forth in the preamble of claim 1 is disclosed in the document SU-A-718 204.
The aim of the present invention is to solve the above problem by providing a device which allows to correct any defects in the straightening of iron rods rapidly and without halting the operation of the machine.
Within the scope of this aim, an object of the present invention is to provide a device for correcting the straightening of iron rods which is simple in concept, safely reliable in operation and versatile in use.
This aim and this object are both achieved, according to the invention, by the present device for correcting the straightening of iron rods and the like and which has the features set forth in claim 1.
The details of the invention will become apparent from the detailed description of a preferred embodiment of the device for correcting the straightening of iron rods and the like, illustrated only by way of non-limitative example in the accompanying drawings, wherein:

figure 1 is a side view of the correction device according to the invention;
figure 2 is a longitudinal sectional plan view of the device.

With particular reference to the above figures, the reference numerals 1 and 2 designate respectively an input head and an output head for the iron rod, which is fed in the direction indicated by the arrow A. The heads 1 and 2 have respective holes 3 and 4 which are axially aligned and through which the iron rod is passed.
The input head 1 axially defines a sleeve 5, at the end of which there is an inlet 3a for the iron rod; said sleeve 5 is rotatably supported, by virtue of a rolling bearing 6, by a support 7 which is rigidly associated with a fixed frame which is not illustrated.
The output head 2 axially defines a tubular shaft 8 which is suitable to be rotated by a gearmotor 9 which is supported by said fixed frame. Conveniently, the gearmotor 9 can be actuated so as to impart appropriate angular strokes within an arc of 360°.
The heads 1 and 2 are similarly flattened and are fixed between a pair of parallel plates 10 which are arranged symmetrically at the sides of the advancement axis of the iron rod. The plates 10 are therefore spaced from each other by an extent equal to the thickness of the heads 1 and 2.
Three appropriately grooved rollers are mounted between the plates 10 so that they are co-planar, and the iron rod is passed between them. Said rollers are in fact arranged along the vertices of a triangle which is crossed, parallel to its base, by the iron rod advancement axis. In practice, two of said rollers, designated by 11a and 11b for the sake of clarity, are arranged on one side with respect to the above mentioned advancement axis, whereas the other roller 11c is arranged on the opposite side.
The rollers 11a, 11b and 11c are rotatably mounted, by virtue of rolling bearings 12, on respective eccentric elements 13a, 13b and 13c which are defined by related shafts 14a, 14b and 14c. The shafts 14a, 14b and 14c are rotatably supported, by virtue of bushes 15, by the opposite plates 10 and are therefore perpendicular to said plates 10.
The first shaft 14a is suitable to be actuated so as to perform angular rotations by a further gearmotor 16 which is fixed externally to one of the plates 10. Said angular rotation is transmitted to the shafts 14b, 14c by means of a crank system which comprises the cranks 17a, 17b and 17c, which are fixed radially at one end of the respective shafts 14a, 14b and 14c; the cranks 17a, 17b have respective levers 19a, 19b which are articulated to them by means of pivots 18; said levers are in turn articulated to the crank 17c about a common axis.
The crank system is arranged externally to the plate 10 which is opposite to the one which supports the gearmotor 16 and is protected by a housing 20.
The operation of the described device is as follows.
The iron rod, subjected beforehand to the straightening operation, is guided by known traction means so that it enters the input head 1 and exits from the output head 2; the rod is thus made to pass between the rollers 11a, 11b and 11c which are mounted between the plates 10.
Said rollers 11a, 11b and 11c are substantially supported by a unit which rotates about the advancement axis of the rod and can be actuated so as to perform an angular rotation by means of the first gearmotor 9.
Therefore, depending on the twist of the iron rod, if any, the assigned operator actuates the gearmotor 9 so as to appropriately rotate said rotating unit. In practice, said unit is rotated angularly until the plane of arrangement of the rollers 11a, 11b and 11c is on the same plane on which the twist occurs.
To correct the twist, instead, the operator actuates the second gearmotor 16, which is rigidly associated with the rotating unit, so as to impart an appropriate angular rotation to the shaft 14a of the first roller 11a; a simultaneous rotation is imparted to the further shafts 14b, 14c of the rollers 11b, 11c by means of the crank system which links them. In particular, the shaft 14b is rotated in the same direction as the shaft 14a, whereas the shaft 14c is rotated in the opposite direction.
The rotation of the shafts 14a, 14b and 14c causes the symmetrical approach or spacing, depending on the direction of rotation, of the two first rollers 11a, 11b toward or away from the opposite roller 11c, i.e. the simultaneous adjustment of the distance of said rollers from the iron rod advancement axis. The angular rotation of the shafts 14a, 14b and 14c in fact causes the movement of the related eccentric elements 13a, 13b and 13c on which the rollers 11a, 11b and 11c are rotatably mounted; essentially, the axis of said eccentric elements rotates about the fixed axis of the shafts, moving toward or away from the rod.
The leveling action of the rollers 11a, 11b and 11c performs the final straightening of the iron rod, correcting any twists.
Naturally, the mutual distance of the rollers 11a, 11b and 11c from the rod advancement axis is adjusted according to the defect to be corrected and to the diameter of said rod.
The fact should be particularly stressed that this correction is performed by the operator without interrupting the normal operation of the line by acting appropriately on the gearmotors 9 and 16.
In the practical execution of the invention, the materials employed, as well as the shape and dimensions, may be any according to the requirements.
Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the scope of each element identified by way of example by such reference signs.

Claims

Device for correcting the straightening of iron rods and the like, comprising a rotating unit which is actuable to perform rotations about an advancement axis of an iron rod to be straightened; and a plurality of rollers (11a,11b,11c) being mounted on said rotating unit so as to be co-planar and between which said iron rod is passed, said rollers being movable for varying the mutual position thereof, said device being characterized in that it further comprises a first motor element (9) for rotating angularly said rotating unit up to a position in which said co-planar rollers are arranged in the same plane in which a twist of the iron rod lays ; a crank system (17a,17b,17c) being connected to said rollers (11a, 11b, 11c) to vary said mutual position thereof; and a second motor element (16), which is supported by said rotating unit, said second motor element (16) actuating said crank system (17a, 17b, 17c) to move said rollers (11a, 11b, 11c) for a simultaneous adjustment of a distance of said rollers (11a, 11b, 11c) with respect to the iron rod advancement axis, said distance being adjustable in accordance with the twist to be corrected and the diameter of the rod.
Device according to claim 1, characterized in that it comprises three rollers (11a,11b,11c) which are arranged along the vertices of a triangle which is crossed, parallel to its base, by the advancement axis of said iron rod, two of said rollers (11a,11b) being arranged on one side with respect to said advancement axis, a further roller (11c) being arranged on the opposite side.
Device according to claim 1, characterized in that said rollers (11a,11b,11c) are rotatably mounted on respective eccentric elements (13a,13b,13c) which are defined by related shafts (14a,14b,14c), said shafts (14a, 14b, 14c) being rotatably supported about fixed axes, said axes being arranged on planes which are perpendicular to said iron rod advancement axis, one of said shafts (14a) being actuatable by said second motor element (16) for performing angular rotations, and said crank system (17a, 17b, 17c) transmitting said angular rotation to the other said shafts (14b, 14c).
Device according to claim 1, characterized in that said crank system comprises respective cranks (17a,17b,17c) which are fixed radially to one end of respective shafts (14a,14b,14c) which define related eccentric elements (13a,13b,13c) on which said rollers are rotatably mounted, said cranks being mutually articulated by virtue of lever means (19a,19b) which are suitable to transmit the angular rotation actuated, at one of said shafts (14a), by said second motor element (16).
Device according to claim 1, characterized in that said rotating unit has an input head (1) and an output head (2) which have respective holes (3,4) which are axially aligned and through which said iron rod is passed, said heads (1,2) being fixed between a pair of parallel plates (10) which are arranged symmetrically at the sides of said iron rod advancement axis.
Device according to claim 5, characterized in that said output head (2) axially defines a tubular shaft (8) which is suitable to be rotated by said first motor element (9).