Patent Application
20250010358
This disclosure relates to a feeding system.
A feeding system of the type considered here has a feeding apparatus which is configured to supply an elongate, wire-shaped or tubular workpiece to a forming machine. The feeding apparatus has a receiving device for receiving a workpiece supply in the form of a coil. The feeding apparatus further has a straightening system which is downstream of the receiving device and which has two adjustable rolling/straightening apparatuses which are connected one behind the other and which have differently orientated straightening planes to straighten the workpiece before introduction into the forming machine. The feeding system further includes a measurement unit for measuring residual curvatures on straightened, wire-shaped or tubular straightening material which has passed through the straightening system of the feeding apparatus and to establish measurement data which represent a residual curvature of the straightened straightening material. On the basis of the measurement data, the rolling/straightening apparatuses of the straightening system can be adjusted so that the straightening material has the desired straightening quality.
Wires, tubes or other elongate semi-finished materials are often present directly after the production thereof in the form of wound material stores (coils) and normally have to be straightened before further processing. The straightening is a production method from the group of forming methods and is used to place the elongate material which is also referred to here as straightening material before further processing into a form which is as linear as possible, that is to say, in a state with slight or negligible residual curvature. In a straightening process, the material is conveyed to this end from a material store through a straightening system and the straightening system produces, from the material, material which is straightened by forming in a straightening operation or straightened straightening material.
Straightening systems of the type considered in this disclosure have at least two rolling/straightening apparatuses. A rolling/straightening apparatus comprises a large number of passive, that is to say, non-rotationally driven straightening rollers having mutually parallel rotation axes which are arranged alternately in a passage direction at opposite sides of a passage path and which define during operation a straightening geometry with circumferential portions which touch workpieces. By a rolling/straightening apparatus, it is possible to change one-dimensional input curvatures (curvatures before introduction into the rolling/straightening apparatus) of a straightening material in a plane so that, after the straightening process, a defined residual curvature is present in this plane. Usually, an end product without any residual curvature, that is to say, a straight end product, is sought. Usually, straightening systems with two rolling/straightening apparatuses which are connected one behind the other and which overcome the input curvatures in two mutually perpendicular planes are used.
Straightening systems with rolling/straightening apparatuses do not rotate and differ in principle in this regard from rotating straightening systems with so-called straightening wings which introduce straightening forces in many different planes.
In adjustable rolling/straightening apparatuses, at least one of the straightening rollers can be positioned in a positioning direction which is orientated transversely relative to the passage direction. It is thereby possible to change the straightening geometry of the rolling/straightening apparatus to obtain a better straightening result. Depending on the type of rolling/straightening apparatus, a straightening roller can be positioned manually, partially automatically or automatically by an associated actuator (for example, servo motor, pneumatic cylinder, hydraulic cylinder and the like) in response to control signals of a control unit.
Inadequate straightening results can be produced, for example, at the beginning of the use of fresh straightening material after a coil change or after switching over to another process. During the current process, material inhomogeneities, changes of the characteristic material values and/or wear on straightening rollers can also lead to the deterioration of the straightening results. Raw material is also subject to production tolerances. Changes can be identified by regular inspections using random samples. If an unacceptable deterioration of the straightening quality is produced, the straightening system should be configured more appropriately by changing the straightening geometry.
In practice, a machine operator requires a great deal of experience and skill to ensure an adequately consistent straightening quality in the machine being supervised. There are already attempts to achieve production processes with reproducibly good straightening quality irrespective of the capabilities of a machine operator.
DE 195 03 850 C1 describes a non-rotating straightening apparatus for bending machines with an integrated measuring apparatus. The straightening apparatus comprises at least one non-rotating straightening mechanism which operates in at least one straightening plane for wire or band material. The straightening mechanism has a plurality of successive straightening rollers which process the material and which are adjustable in the straightening plane and transversely relative to the passage axis of the material by at least one actuating drive. In the passage direction of the material downstream of the straightening mechanism, there is provided a material bending measurement apparatus in which at least one measurement path for a material portion which is predetermined in terms of the length is provided and along the measurement path at least one mechanical and/or electronic and/or optical scanning apparatus which establishes the extent of the bending and the bending direction is arranged, wherein signals which represent the measured bending of the material portion can be generated with the scanning apparatus and wherein the actuating drive of at least one straightening roller is an actuating drive which responds to the signals with corrective adjusting movements.
It could therefore be helpful to provide a feeding system of the type mentioned in the introduction which allows precise measurements of the residual curvature on straightened straightening material and which provides meaningful measurement results which can be used during straightening and during operation of the straightening system to optimize the straightening geometry of the rolling/straightening apparatuses in a rapid and systematic manner so that good straightening results can be achieved.
We provide a feeding system including a feeding apparatus for feeding an elongate, wire-shaped or tubular workpiece to a forming machine, wherein the feeding apparatus has a receiving device for receiving a workpiece supply in the form of a coil and a straightening system which is downstream of the receiving device and which has two adjustable rolling/straightening apparatuses which are connected one behind the other and which have differently orientated straightening planes for straightening the workpiece before introduction into the forming machine, a measurement unit for measuring residual curvatures on straightened wire-shaped or tubular straightening material which has passed through the straightening system of the feeding apparatus, and for establishing measurement data which represent a residual curvature of the straightened straightening material, characterized in that a cutting device for separating rod-shaped portions of a predeterminable length from the straightening material which has passed through the straightening system, the measurement unit has a measurement apparatus for receiving a rod-shaped portion, which is separated from the straightening material, of the straightening material which has passed through the straightening system in a measurement position, and the measurement unit is configured for a measurement which is specific to the straightening plane and which allows association of the curvature portions which represent the measurement data with the different straightening planes of the rolling/straightening apparatuses.
Some examples provide a feeding system including: a feeding apparatus for feeding an elongate, wire-shaped or tubular workpiece to a forming machine, wherein the feeding apparatus has a receiving device for receiving a workpiece supply in the form of a coil and a straightening system which is downstream of the receiving device and which has two adjustable rolling/straightening apparatuses which are connected one behind the other and which have differently orientated straightening planes for straightening the workpiece before introduction into the forming machine; a measurement unit for measuring residual curvatures on straightened wire-shaped or tubular straightening material which has passed through the straightening system of the feeding apparatus, and for establishing measurement data which represent a residual curvature of the straightened straightening material; characterized in that a cutting device for separating rod-shaped portions of a predeterminable length from the straightening material which has passed through the straightening system the measurement unit has a measurement apparatus for receiving a rod-shaped portion, which is separated from the straightening material, of the straightening material which has passed through the straightening system in a measurement position; and the measurement unit is configured for a measurement which is specific to the straightening plane and which allows association of the curvature portions which represent the measurement data with the different straightening planes of the rolling/straightening apparatuses.
Some examples provide a feeding system, wherein the measurement unit has a cutting device for separating rod-shaped portions of predeterminable length from the straightening material which has passed through the straightening system, wherein preferably together with the measurement apparatus the cutting device is mounted on or at a common frame.
Some examples provide a feeding system, wherein the measurement unit is configured in such a manner that the straightening material can be measured in the rotational position in which it passed through the straightening system.
Some examples provide a feeding system, further including rotation prevention devices which are configured in such a manner that a rotational position of a separated rod-shaped portion which is provided for measurement about the longitudinal axis thereof remains unchanged between the straightening and the measurement so that the straightening material can be measured in the rotational position in which it passed through the straightening system, wherein there are preferably provided actuatable rotation prevention devices which can be switched in response to control signals of a control unit between a neutral configuration without any engagement with the straightening material and an engagement configuration with contact with the straightening material.
Some examples provide a feeding system, further including a control unit which is configured in an operating mode so that the cutting device and the measurement apparatus are controlled in such a coordinated manner that a front end portion of the straightened straightening material is conveyed by a controlled advance to a measurement position in the measurement apparatus, afterwards the straightening material is secured to prevent rotation, in particular clamped in a horizontal direction, by rotation prevention devices of the measurement unit, and afterwards the cutting device is controlled to separate the rod-shaped portion which is intended to be measured from the remainder of the straightening material.
Some examples provide a feeding system, wherein the measurement apparatus has, at an inlet side, a first clamping apparatus and, with spacing therefrom in a longitudinal direction, a second clamping apparatus, wherein in a region between the first and second clamping apparatuses components of a measurement system are arranged, in that a measurement plane (524) which is orientated transversely, particularly perpendicularly to the longitudinal direction, is defined and configured to determine the position of the deposited rod-shaped portion in the measurement plane, wherein each of the clamping apparatuses preferably has a support roller which is mounted with a horizontal rotation axis and two transverse positioning rollers which are adjustable by a drive in such a manner that an introduced rod-shaped portion can be fixed at a fixing location which is defined in a vertical direction and in a horizontal direction.
Some examples provide a feeding system, wherein a spacing, measured parallel with the longitudinal direction, of the clamping apparatuses is adjustable steplessly, wherein preferably the clamping apparatuses are mounted on carriages which run on guide rails which are fixed at the upper side of a horizontally orientated base plate of the measurement system and/or components of the measurement apparatus are fixed to a carrier which is mounted on a carriage which can be displaced on the guide rails which also guide the clamping apparatuses.
Some examples provide a feeding system, wherein a measurement system of the measurement apparatus is an optical measurement system for determining the position of the rod-shaped portion in a measurement plane which is located between the clamping apparatuses, wherein preferably the measurement system has a first laser unit and a second laser unit which generate a laser light curtain which extends in the measurement plane in measurement directions which are orientated transversely, in particular perpendicularly to each other, wherein a sensor unit with photo-sensitive sensors for detecting a shadow projection of the part, which extends through the measurement plane, of the rod-shaped portion is arranged opposite a laser unit.
Some examples provide a feeding system, wherein the workpiece supply is wound on a replaceable reel and the receiving device (330) is configured so that the reel can be received by the receiving apparatus and is supported rotatably about a horizontal rotation axis in the received state.
Some examples provide a feeding system, wherein the receiving apparatus has two axially parallel carrier rollers with horizontal rotation axes, on which the reel can be positioned in such a manner that the circumference of lateral elements of the reel is positioned on the two carrier rollers and the position of the rotation axis is fixed in space, wherein preferably a drive which can be controlled via a control unit and which is in engagement with one of the carrier rollers and can drive them under the control of the control unit is provided.
Some examples provide a feeding system, wherein the receiving apparatus has a redirecting device having an upper redirecting roller for receiving the workpiece which is unwound from the workpiece supply and a device which is arranged under the upper redirecting roller for receiving a workpiece loop before introduction into the straightening system.
Some examples provide a feeding system, wherein the device arranged under the upper redirecting roller for receiving a workpiece loop includes a vertically orientated buffer store in the form of an upwardly, partially open storage box and an auxiliary intake device which is arranged between the upper redirecting roller and the buffer store and which can be driven by an auxiliary drive and is configured to convey the workpiece at a predeterminable conveying speed to the downstream buffer store, wherein preferably a sensor system is provided for detecting the filling level of the buffer store and for generating sensor signals which represent the filling level, wherein a control device is configured so that the conveying speed of the auxiliary intake device can be controlled in accordance with sensor signals of the sensor system.
Some examples provide a feeding system, wherein the device which is arranged under the upper redirecting roller for receiving a workpiece loop has a lower redirecting roller, the upper redirecting roller and the lower redirecting roller are rotatably supported in an axially parallel manner on a vertical carrier, wherein preferably the upper redirecting roller is in the form of a vertically displaceable dancer roller with resilient restoring and interrogation of the position of this redirecting roller is used to control a drive motor for reel rotation and/or wherein the lower redirecting roller is wrapped around over approximately three-quarters of the circumference thereof and has at the upper side thereof an outlet which is at the height of an inlet-side through-opening of the straightening system so that the workpiece material can run from the lower redirecting roller directly in a horizontal direction into the straightening system.
Some examples provide a feeding system, wherein the straightening system has two rolling/straightening apparatuses which are connected one behind the other and which are adjustable independently of each other, wherein rotation axes of straightening rollers of the straightening apparatuses are orientated orthogonally relative to each other, preferably in such a manner that a first straightening apparatus defines a vertical straightening plane and a subsequent second straightening apparatus defines a horizontal straightening plane.
Additional advantages and aspects will be appreciated from the claims and the description of examples which are explained below with reference to the Figures, in which:
A significant component of the feeding system is a feeding apparatus which is configured to feed an elongate, wire-shaped or tubular workpiece to a forming machine. The feeding apparatus has a receiving device for receiving a workpiece supply in the form of a coil and a straightening system which is downstream of the receiving device. The straightening system comprises two adjustable rolling/straightening apparatuses which are connected one behind the other and which have differently orientated straightening planes for straightening the workpiece before introduction into the forming machine. The straightening planes are preferably orientated perpendicularly to each other, in particular one of the straightening planes is horizontal and the other is vertical. The feeding system consequently produces continuous material (wire or tube) which is straightened to a greater or lesser extent from the wound material of the coil.
To be able to ensure adequate straightening quality, there is associated with the feeding system a measurement unit which is configured for measuring residual curvatures on the straightened straightening material which has passed through the straightening system of the feeding apparatus. By the measurements, there are established measurement data which represent a residual curvature of the straightened straightening material and which consequently allow a quantitative description of the curvature state. The measurement unit is adapted to the constructive and functional properties of the feeding apparatus to allow a measurement which is as free from errors as possible.
The measurement unit is a unit which is separate from the feeding apparatus and which can be brought into active connection with the feeding apparatus temporarily or in a time-limited manner for the purposes of measurement to carry out configuration operations. The feeding apparatus can afterwards be brought into the work position thereof at the forming machine to which the straightened material is intended to be supplied. The measurement unit can also be used to configure the straightening systems of other machines which are provided with straightening systems.
Our feeding system has the following specific features.
The feeding system comprises a cutting device for separating rod-shaped portions of a predetermined length from the straightening material which has passed through the straightening system. The measurement is then carried out on rod-shaped portions (rods) of predetermined length (rod length) which have been separated by the cutting device from the straightening material which has passed through the straightening system. During a measuring operation, a single rod is measured. To allow such a measurement, the measurement unit comprises a measurement apparatus to receive one rod-shaped portion in a measuring position and for establishing measurement data which represent a residual curvature of the straightened straightening material. In this instance, the measurement unit is configured for a measurement which is specific to the straightening plane and which allows at least approximately unambiguous association of the measurement data or the curvature portions which represent the measurement data with the different straightening planes of the rolling/straightening apparatuses.
Our system is based inter alia on the following considerations. A rolling/straightening apparatus straightens in only one single straightening plane. If in the straightening system two rolling/straightening apparatuses which are passed through one behind the other are provided with different straightening planes, in particular ones which are orientated perpendicularly to each other, curvatures in the two straightening planes can be assessed independently of each other as a first approximation. It has been recognized that it is important for a targeted adjustment or positioning of the straightening rollers during the straightening process or in the context of an adjustment operation to be able to assign the measurement results established using the straightened straightening material with the individual straightening planes in an unambiguous manner. Measurements which allow this are referred as “measurements which are specific to straightening planes or selective in terms of straightening planes”.
It is known to measure the linearity or the residual curvature in a portion of the straightened straightening material which is still joined to adjacent portions of the straightening material. Where applicable, it can be measured with the straightening material passing through, that is to say, in phases in which the straightening material moves forward. Where applicable, the straightening material can also be temporarily stopped for the measurement (cf. DE 195 03 850 C1). It is considered to be disadvantageous that it may be in this instance that the stresses and forces which act from other portions of the straightening material may influence the shape of the measured portion so that the true curvature state is not measured.
The measurement on rod-shaped portions or rods of predeterminable length which have been separated from the straightening material after passing through the straightening system by a cutting device is carried out. The straightening material, which is intended to be measured, of the rod can have its stress reduced as a result of the separation from the following remainder without any external constraint so that the shape of the rod represents the true curvature relationships at least approximately in a non-corrupted manner. According to the recognitions of the inventor, significantly more positively interpretable measurement results can be achieved if a relatively short rod-shaped portion is separated from the straightened straightening material and this rod is then measured or is subjected to a linearity test.
With measurement methods which are relatively simple to carry out and to evaluate, precise quantitative statements concerning curvature portions can thereby be obtained and can be unambiguously associated with the different straightening planes during the evaluation.
Preferred rod lengths are generally substantially smaller than one meter and they may be, for example, between 300 mm and 700 mm depending on the rigidity of the straightened material.
A number of advantages of this configuration may also be understood as follows. Many conventional linearity measurement systems are configured to allow a global statement concerning the curvature state of straightening material, for example, to differentiate adequately well straightened straightening material with the desired straightening quality from straightening material with inadequate straightening quality. Conversely, the measurement unit or the measurement method can not only establish global values for the residual curvature but the information resulting from the measurement concerning the curvature state of the rod-shaped portion can also be separated into curvature portions which can clearly be associated with the individual straightening planes of the straightening system. With such a measurement which is specific to straightening planes or selective in terms of straightening planes, it is possible to detect quantitatively which portion of an established residual curvature was caused by which of the at least two straightening apparatuses.
With this information, which is broken down in accordance with straightening planes, about the curvature state of the straightening material, for example, a targeted adjustment of the rolling/straightening apparatuses can then be carried out, for example, in the context of the straightening of the straightening system to arrive at a suitable adjustment of the straightening rollers with a small number of attempts. If, for example, a straightening system has a first rolling/straightening apparatus with a vertically orientated first straightening plane and, in a state connected downstream thereof, a second rolling/straightening apparatus with a horizontal straightening plane, horizontal and vertical portions of the residual curvature can be quantified separately from each other using the measurement data. Accordingly, for example, in a straightening process, when a determined residual curvature is carried out mainly or exclusively from one of the straightening planes, the adjustment of straightening rollers can be concentrated on the straightening apparatus, the straightening plane of which is affected by the excessively powerful residual curvatures.
The measurement unit can operate with separated rods which were separated using a cutting device which belongs to a machine which is connected upstream in the process, for example, a straightening and cutting machine, the end products of which are straightened rods. A straightening and cutting machine generally comprise a feeding apparatus, a length measurement device and a cutting device which is controlled by signals of the length measurement device. In these instances, no individual cutting unit is required at the measurement unit.
According to a further development, the measurement unit has a cutting device for separating rod-shaped portions of predeterminable length from the straightening material which has passed through the straightening system. The measurement apparatus is connected downstream of the cutting device in the material flow direction. As a result of the integrated cutting device, the measurement unit is capable, as an autonomous unit, of separating rod-shaped portions of a suitable length from straightened continuous material and of carrying out linearity measurements or measurements of the residual curvature on these portions.
Together with the measurement apparatus, the cutting device can be mounted on or at a common frame of the measurement unit to ensure a fixed positional relationship and to form a functional unit which can be used, for example, as a configuring station. One example of such an autonomous measurement unit is explained in greater detail below.
To carry out a measurement which is specific to straightening planes or selective in terms of straightening planes, there is preferably provision for the measurement unit to be configured in such a manner that the straightening material is measured in the rotational position in which it passed through the straightening system. The term “rotational position” refers in this instance to the rotational position or rotational orientation with respect to an inherent rotation about the longitudinal axis of the straightening material. Although measurement data which are specific to straightening planes could also be established in that a potential rotation of the straightening material between the separation and measurement is detected in technical measurement terms and the measurement data which are established with the measurement apparatus are then corrected with respect to the rotation direction, it is considered to be significantly easier and more precise to exclude such inherent rotations by technical method measures and constructive measures.
Since, for the measurement, a separated rod with a suitable length is separated from the remainder of the straightening material, an inherent rotation of the rod about the longitudinal axis thereof should be avoided between the act of separation and the act of measurement to allow an unambiguous association of the measurement results with the corresponding rolling/straightening apparatus. This can be a problem particularly during the processing of round material if it is set down, for example, so that it rolls along an oblique surface between separation and measurement. When material with a profiled cross section is processed, for example, with a rectangular cross section, simple measures may be sufficient to prevent inherent rotation, for example, by placing the straightening material with one of the planar faces thereof on a linear or planar storage location.
According to a further development, the measurement unit is characterized by rotation prevention devices which are configured in such a manner that a rotational position of a separated rod-shaped portion which is provided for measurement about the longitudinal axis thereof remains unchanged between the straightening and the measurement so that the straightening material can be measured in the rotational position in which it passed through the straightening system. Therefore, it is ensured by rotation prevention devices and/or rotation prevention measures that the rotational position of the material about the longitudinal axis thereof remains unchanged between straightening and measurement. There are preferably provided active or actuatable rotation prevention devices which can be switched in response to control signals of a control unit between a neutral configuration without any engagement with the straightening material and an engagement configuration with contact with the straightening material.
According to a further development, the measurement unit has a control unit which is configured in an operating mode so that the cutting device and the measurement apparatus are controlled or operated in such a coordinated manner that a front end portion of the straightened straightening material which was conveyed by a controlled advance to a measurement position in the measurement apparatus is secured to prevent inherent rotation by rotation prevention devices of the measurement system, for example, by clamping, and only afterwards is the cutting device controlled to separate the rod-shaped portion which is secured to prevent rotation and which is intended to be measured from the remainder of the straightening material. By the clamping of the straightening material or another fixing measure which prevents rotation before the separation, the separated straightening material can be reliably stopped.
The coordination between cutting and measurement can be carried out particularly simply in measurement units with an integrated cutting device. However, technical control coordination is also possible with external cutting devices, that is to say, ones which are not part of the measurement unit but instead belong to another unit.
In many variants, the straightening material is initially conveyed into the region of the measurement apparatus, received at that location in a manner secured to prevent rotation and only afterwards separated from the remainder of the straightening material. In one example of the measurement apparatus, the rotation prevention means can be ensured by elements, which are displaceable in a transverse direction, of a clamping apparatus.
It is also possible to provide a rod transport device which is configured to grip a portion, which is intended to be separated, of the straightening material before carrying out the cutting operation, to transport it after separation from the remainder of the straightening material to the measurement apparatus and to insert or deposit and release it at that location with an unchanged rotational position after the rod-shaped portion has been received in a manner secured to prevent rotation in the measurement apparatus.
Where applicable, an in-process measurement/control can thereby also be carried out by, during the production process, rods which are straightened regularly or irregularly in accordance with a predetermined pattern or as required are supplied to the measurement apparatus and measured at that location to assess the straightening quality and where applicable to carry out compensating changes of the adjustment of the straightening system. The rods which are removed from the material flow for test purposes can then, if possible, be supplied to the following production step again, but this is not absolutely necessary. Therefore, from time to time straightened rods can be removed from the material flow for test purposes and where applicable returned to the material flow again after the measurement has been completed.
According to a further development, the straightened straightening material is fixed, for the purposes of measurement, at a first fixing location and at a second fixing location which is spaced apart from the first fixing location so that for each of the fixing locations a vertical position and a transverse position of the straightening material (for example, in a horizontal direction transverse to the longitudinal direction of the rod) is predetermined and a straightening material portion which is located between the fixing locations is force-free except for gravitational forces. The position of the straightening material is then measured in a measurement plane which is located between the first and second fixing locations. They can be located, for example, centrally between the fixing locations. The residual curvature of the wire portion which is located between the fixing locations is then established using positional data for the position of the straightening material at the first fixing location, the second fixing location and the measurement plane.
In constructive terms, there can be provided in the measurement apparatus a first and a second clamping apparatus which provide at the corresponding fixing locations a support for the straightening material and which have clamping elements which can be displaced in a transverse direction and which can thereby fix the transverse position in a state moved into contact against the straightening material. At the same time, it is thereby possible to achieve a way of securing against inherent rotation.
According to a further development, the measurement apparatus has, at a side which faces or is intended to face the cutting device (inlet side), a first clamping apparatus and, with spacing therefrom in a longitudinal direction, a second clamping apparatus, wherein in a region between the clamping apparatuses components of a measurement system are arranged, in that a measurement plane which is orientated transversely, particularly perpendicularly to the longitudinal direction of the measurement apparatus, is defined and configured to determine the position of the deposited rod-shaped portion in the measurement plane. The measurement plane is preferably located centrally between the clamping apparatuses, where typically the greatest redirections, in accordance with the amount, of the fixed rod-shaped portion may be anticipated, which promotes measurement precision.
According to a further development, each of the clamping apparatuses has a support roller which is mounted with a horizontal rotation axis and two transverse positioning elements which are adjustable by a drive, for example, transverse positioning rollers, in such a manner that an introduced rod-shaped portion can be fixed at a fixing location which is defined in a vertical direction and in a horizontal direction. In this instance, the upper portion of the covering face of the support roller can determine the vertical position while the laterally positioned transverse positioning elements predetermine the position in a horizontal direction.
In such examples of the measurement apparatus, the rotation prevention member can be ensured by the transverse positioning elements which are displaceable in a transverse direction, in particular rollers, of the clamping apparatus which consequently act as rotation prevention devices. If a rod-shaped portion is laterally clamped gently by transverse positioning elements with a vertical rotation axis, only the degree of freedom of the rotation of the rod about its longitudinal axis is substantially prevented while the clamping in a horizontal direction between substantially point-like contact locations between the support rollers and the outer side of the rod-shaped portion does not significantly impede a potential sagging of the rod or redirections in vertical directions. Consequently, the true curvature state which is supported at two locations which are spaced apart from each other at a rod-shaped portion and which is otherwise exposed substantially only to gravitational force can be measured.
As an alternative to roller-like transverse positioning elements, other transverse positioning elements which may where appliable not be supported in a movable manner, for example, blocks with convex-curved contact faces, may also be provided. Preferably, the contact faces are intended to be configured with respect to the workpiece so that only a substantially point-like or small touching contact is produced so that the straightened rod is clamped only in a horizontal direction between substantially point-like contact locations so that a potential deflection in a vertical direction is not substantially impeded.
Consequently, the rotation prevention members may be elements with a suitable geometry which allow a point-like or linear contact between the clamping apparatus and the rod-shaped portion. This includes, for example, the mentioned rollers but also non-rotatable elements which have a tip or a radius at least in the contact region, for example, therefore, a cylindrically or spherically curved contact face.
According to a further development, a spacing, measured parallel with the longitudinal direction, of the clamping apparatus is adjustable steplessly so that the measurement apparatus can be adapted readily to rod-shaped portions with different lengths. The rod-shaped portions which are provided for the measurement are in most instances substantially shorter than one meter, the length thereof may be dependent on the rigidity of the straightened material, for example, between 300 mm and 700 mm, where applicable (with relatively thin rod materials) also less.
Although one of the clamping apparatuses can be fixedly mounted and only the other can be displaceable, preferably the clamping apparatuses are mounted on carriages which run on guide rails which are fixed at the upper side of a horizontally orientated base plate of the measurement system. Consequently, both clamping apparatuses can be displaced steplessly in the same axis and can then be fixed at the desired positions.
To be able to correctly position the measurement plane for different rod lengths, there is provision according to a further development for components of the measurement apparatus to be fixed to a carrier which is mounted on a carriage which can be displaced on the guide rails which also guide the clamping apparatuses. Consequently, an extremely stable arrangement, which can readily be adapted to different dimensions of the rod-shaped portions which are intended to be measured, is provided.
For the detection of the straightening material in technical measurement terms, after passing through the straightening system, that is to say, for the measurement, any measurement apparatus which provides quantitative statements concerning the residual curvature in the straightening planes of the rolling/straightening apparatuses and which allows an unambiguous association of the measured residual curvatures with the straightening planes can be used in principle.
The measurement variable does not have to directly correspond to the residual curvature, it is sufficient if the measurement variable constitutes a value which represents the residual curvature. The measurement can be carried out in a tactile manner (that is to say, touching) or contactlessly, for example, by optical and/or electromagnetic devices. In this instance, the important aspect is that the measurement technology for adjusting a straightening apparatus allows statements concerning the residual curvature or the straightening quality in the straightening plane in which the respective straightening apparatus acts.
According to a further development, the measurement apparatus comprises an optical measurement system which generates by laser radiation two laser light curtains which are located in the measurement plane and which are perpendicular to each other and detects by opposite, light-sensitive sensors, whereby the position of the straightening material in the measurement plane in two directions can be determined in a highly precise manner shadow projection. The contactless measurement does not influence the shape of the rod to be measured.
The residual curvature which is present in the plane of curvature and which is influenced by the respective rolling/straightening apparatus (plane perpendicular to the rotation axes of the straightening rollers) can then be established simply from the spacing present in the measurement plane between the measured position of the wire portion and a reference position which is located in the measurement plane and which would be present if the straightening material had the desired residual curvature. This reference position is preferably not located on a straight line which connects the two fixing locations but instead takes into consideration the deflection, which is present as a result of gravitational force, of a straightening material which is positioned on the fixing locations. To determine the position of this reference point, suitable material-specific straightening material parameters can be used, where applicable in a manner modified by the circumstance that the straightening material is formed multiple times in the straightening process and is thereby changed where applicable with respect to the resilient properties thereof.
Different examples of the feeding apparatus are possible.
According to a further development, the workpiece supply is wound on a replaceable reel and the receiving device is configured so that the reel can be received by the receiving apparatus and is supported rotatably about a horizontal rotation axis in the received state. An advantage of a horizontal orientation of the reel axis is that, to continue to guide the unwound material, there are used components which can be arranged high above the hall floor so that only a small lateral construction spatial requirement is present. In variants, a vertical orientation of the reel axis may also be provided.
A particularly comfortable and simple reel change is achieved in many examples in that the receiving apparatus has two axially parallel carrier rollers with horizontal rotation axes, on which the reel can be positioned in such a manner that the circumference of lateral elements of the reel is positioned on the two carrier rollers and the position of the rotation axis is fixed in space. When the reel is changed, it is not then necessary to disassemble or retrofit bearing units in the region of the rotation axis.
Preferably, the reel can be actively driven. Thus, for example, a drive which can be controlled via a control unit and which is in engagement with one of the carrier rollers and can drive them under the control of the control unit may be provided. As a result of an active reel drive, a contribution can be made to the material-protecting material conveying with only slight fluctuations in stress.
According to a further development, the receiving apparatus has a redirecting device having an upper redirecting roller to receive the workpiece which is unwound from the workpiece supply and a device which is arranged under the upper redirecting roller to receive a workpiece loop before introduction into the straightening system.
According to a further development, the device arranged under the upper redirecting roller to receive a workpiece loop comprises a vertically orientated buffer store in the form of an upwardly, partially open storage box and between the upper redirecting roller and the buffer store an auxiliary intake device which can be driven by an auxiliary drive and which is configured to convey the workpiece at a predeterminable conveying speed to the downstream buffer store.
Preferably, a sensor system is provided to detect the filling level of the buffer store and to generate sensor signals which represent the filling level, wherein a control device is configured so that the conveying speed of the auxiliary intake device can be controlled in accordance with sensor signals of the sensor system. Consequently, it is possible to avoid overfilling or underfilling the buffer store.
It is also possible for the device which is arranged under the upper redirecting roller to receive a workpiece loop to have a lower redirecting roller. This roller can be arranged and sized so that the material can run into the straightening system in a horizontal direction directly afterwards.
The measurement unit and the feeding apparatus are system components of the feeding system. These units may be fabricated separately as individual units independent of each other or the larger system as a whole.
Examples of feeding systems and methods and systems of configuring a straightening system which is configured to straighten wire-shaped straightening material which is passing through are described below. The straightening material, in the example a wire, can be further processed in a forming machine to produce straight or bent formed components from the straightening material. The straightening system is integrated in a feeding apparatus which is provided to supply a forming machine (not illustrated in greater detail) with straightened wire as the input material in a current production operation. To configure the feeding apparatus, a measurement unit which belongs to the feeding system and which is structurally and functionally adapted to the feeding apparatus and which acts as a temporarily used auxiliary device during configuration is used.
In the state configured to be ready for operation, the wire processing installation comprises a forming machine (not illustrated) which may be, during the production of helical springs, for example, in the form of a spring winding machine.
Furthermore, an apparatus 300 for feeding the elongate, rod-shaped workpiece material to the forming machine is provided. The apparatus 300 is also referred to for short as a feeding apparatus 300. The feeding apparatus of the example is a forming machine which produces a straightened wire from more or less powerfully curved wire of the wound wire store by forming.
An object of the feeding apparatus 300 involves feeding the wire in a linearly straightened form (residual curvature near zero in the tolerance range) at any time as precisely as possible at the speed required at this time to a downstream forming machine or the intake device thereof. The feeding apparatus 300 has an individual control unit 390 which communicates with the control unit of the forming machine. The functionalities of the two control units can be integrated in a single control unit.
After the configuration has been completed at the configuration site, the feeding apparatus is moved to the working position thereof at the forming machine which is intended to be supplied. To this end, the illustrated components are mounted on a movable platform which can be linearly displaceable, for example, on guide rails or rotatably supported about a vertical rotation axis or may be movable in a non-guided manner (for example, on rollers or wheels).
The feeding apparatus comprises a feeding unit 310 which has a receiving device 330 to receive a workpiece supply 381 in the form of a coil and a downstream straightening system 400 to straighten the workpiece before introduction into the forming machine. The straightening system 400 is shown in
The workpiece supply (coil) is stored on a replaceable reel 335 which is received by a receiving apparatus 330 and which is rotatably supported about a horizontal rotation axis in the received state. The bearing is carried out not in the region of the rotation axis of the reel but instead two axially parallel carrier rollers 332, 333 with horizontal rotation axes are arranged in the base region. These carrier rollers are components of the receiving apparatus 330. The reel is positioned on the two carrier rollers so that the circumference of the disk-like lateral elements of the reel is positioned on the two carrier rollers and the position of the rotation axis is fixed in space. In the example, this involves an active reel with its own drive. The drive 334 is in engagement with the front carrier roller 333 and can drive it under the control of the control unit 390.
The unwound wire is guided via a redirecting device 340 which has an upper redirecting roller 340-1 and a lower redirecting roller 340-2 which are rotatably supported on a vertical carrier 341 in an axially parallel manner. The upper redirecting roller is in the form of a vertically displaceable dancer roller with resilient restoring. The drive motor for the carrier/drive roller is controlled by interrogating the position of this roller. The lower redirecting roller is, for example, wrapped around over three-quarters of the circumference thereof in such a manner that the outlet, that is to say, the upper side of the lower redirecting roller 340, is at the height of the inlet-side outlet opening of the straightening system 400.
The wire is therefore guided by the lower redirecting roller substantially horizontally relative to the straightening system 400. There is located between the redirecting device and the straightening system a wire guiding device 375, the outlet of which is aligned with the inlet of the downstream straightening system 400. A wire end identification device can be integrated in the wire guiding device.
An alternative construction is illustrated or indicated in
The buffer store is configured so that the workpiece can form a workpiece loop 111 of variable length in the buffer store between the inlet and the outlet. As a result, differences in speed between the regions before and after the buffer store can be compensated for. Preferably, a sensor system is provided to detect the filling level of the buffer store and to generate sensor signals which represent the filling level. The control device can then be configured in such a manner that the conveying speed of the auxiliary intake device can be or is controlled in accordance with sensor signals of the sensor system. A buffer store can also be installed horizontally where necessary so that the workpiece loop is formed in a plane which is orientated substantially horizontally. For additional details and variants, reference may be made to WO 2020/224977 A1, the content of which with respect to the structure of the feeding device is incorporated in the content of this description by reference.
The straightening system 400 comprises two rolling/straightening apparatuses 400-1, 400-2 which are connected directly one after the other and which can be adjusted independently of each other and which have a number of axially parallel straightening rollers. In this instance, seven straightening rollers are provided but other numbers, for example, five to nine are also possible. The rotation axes of the straightening rollers of the straightening apparatuses which are connected one behind the other are orientated orthogonally relative to each other.
In a rolling/straightening apparatus, straightening rollers produce as a result of eccentric adjustment in relation to a neutral axis of the material to be straightened alternating bends which deform the material to be straightened into the plastic range and thereby straighten it. Unlike a rolling/straightening machine, the straightening rollers are passive in this instance, or not driven, therefore there are no drives to rotate the straightening rollers. The wire is drawn through by the rolling/straightening apparatuses. To this end, there is provided an intake device 385 which is arranged downstream of the straightening system 400 in the material flow direction and which inter alia is used to pull the wire material through the two rolling/straightening apparatuses 400-1, 400-2 of the straightening system 300 in the direction of subsequent components.
The components of the straightening system 400 are carried by a frame member, in which the control unit 390 of the feeding unit 310 can also be received. The frame member also carries the intake device 385. In the example, the intake device 385 is in the form of a roller intake and may, in other examples, also be in the form of a belt intake device or pincer type intake. There may be provided downstream of the intake device 385 in the material flow direction an optional, where applicable manually actuatable clamping device, with which the axial position of the introduced wire where necessary can be fixed.
Other details are explained using the example of the first rolling/straightening apparatus 400-1 which acts in the vertical plane (x-z plane).
The first rolling/straightening apparatus 400-1 has seven passive straightening rollers R1, . . . R7 with mutually parallel, horizontal rotation axes which are arranged in a throughflow direction 115 alternately at opposite sides of a throughflow path (parallel with the x axis). The straightening rollers define the active straightening geometry of the rolling/straightening apparatus during operation of the straightening system with the circumferential portions thereof which touch the straightening material 110. The first rolling/straightening apparatus 400-1 changes the curvature substantially only in a vertical plane (x-z plane), the straightening plane. The second rolling/straightening apparatus 400-2 which is responsible for the straightening in a horizontal plane is configured similarly, in this instance the straightening roller rotation axes extend vertically.
In the example, all seven straightening rollers are in the form of automatically positionable straightening rollers and can be positioned bi-directionally in response to control signals of the control unit 390 automatically by servo-motor drives 405-1, . . . 405-7 independently of each other in a positioning direction which is orientated perpendicularly to the throughflow direction (parallel with the z axis).
There are also variants, in which all the straightening rollers can be adjusted manually. To this end, for example, adjustment screws and positioning indications may be provided. There are also examples, in which some of the straightening rollers (for example, two, three or four) can be positioned automatically and some other straightening rollers (for example, three, four or five) can be positioned manually.
As a result of the large number of degrees of freedom during the adjustment, one machine operator with a great deal of experience is required for the correct adjustment of a rolling/straightening apparatus. In any instance, the adjustment operation or the configuration takes a considerable time.
The configuration is simplified in that a measurement unit 350 which is adapted to the constructive and functional relationships of the feeding apparatus 300 and which allows a targeted configuration procedure in a short time period belongs to the feeding system. The measurement unit 350 acts as a configuring station.
The measurement unit or the configuring station 350 comprises a cutting device 370 with which during the adjustment operations on the straightening system straightened, rod-shaped wire portions 110-A are cut off the supplied wire as tests and are therefore provided for a linearity test. In the example, an automated cutting device 370 is provided, alternatively a manually actuatable cutting device may be provided. Furthermore, the configuring station 350 has a measurement apparatus 500.
The wire portions or wire rods 110-A which are separated by the cutting device are checked for linearity or residual curvatures by the downstream measurement apparatus 500. In this instance, it is ensured by rotation prevention devices that the rotational position of the material rod which is provided to measure remains unchanged about the longitudinal axis thereof so that the wire is measured in the rotational position in which it has passed through the straightening system.
The measurement apparatus 500 and the associated cutting device 370 are components of the measurement unit 350 which where applicable together with other components form an autonomous unit which can act as a configuring station 350. Therefore, the same reference numeral 350 is used for the configuring station and the measurement unit.
In the region between the clamping apparatuses 510-1, 510-2, components of a measurement system 520 are mounted. They are carried by a cross-like carrier 522 which is mounted on a carriage which can be displaced on the guide rails 501 which also guide the clamping apparatuses. The measurement system 520 is an optical measurement system which can determine the position of the positioned wire in a highly precise manner in a measurement plane 524 which is orientated perpendicularly to the x direction. Above the straight connection line between the fixing locations, there is arranged a second laser unit 525-2 which generates a laser light curtain which is located in the measurement plane 524 and which falls at the opposite side into the detection range of a photo-sensitive sensor 527-2 so that, in the shadow thrown, the position of the wire in a transverse direction (horizontal direction) can be precisely detected. The position in a vertical direction is detected by a first laser unit 525-1 and the opposite sensor 527-1. The measurement is preferably carried out at the center between the two fixing elements by the two lasers in a horizontal or vertical direction.
The enlarged detail in
During the evaluation, it is taken into consideration that the wire rod is subject to a specific bending simply as a result of gravitational force, the extent of which depends on characteristic material values and the spacing between the fixing locations. This contribution is subtracted during the evaluation. As a result of the measurement, there is produced a quantitative value for the residual curvature which may have both contributions in a horizontal direction and in a vertical direction. On the basis of these measurement values, the straightening geometry of the rolling/straightening apparatuses is then intended to be adjusted so that the residual curvature disappears for the next wire piece.
We see a potential problem in the processing of round material. It may be that a round rod which still has a substantial convexity in the horizontal plane after the straightening operation may roll automatically into a stable rotational position, in which the convexity hangs downward, when it is positioned in the measurement apparatus. That would imitate a convexity in a vertical direction which is not actually present, whereby there would result incorrect measurement results and consequently incorrect positionings and/or incorrect positionings at the incorrect straightening apparatus.
To ensure that the measurement results can be associated precisely with the different straightening planes or rolling/straightening apparatuses (horizontal and vertical), where necessary special measures ensure that the wire rod provided for the measurement cannot rotate about its own longitudinal axis between the separation from the remainder of the straightening material and the measurement. The measurement unit 350 is configured to this end for a measurement which is specific to the straightening plane or selective in terms of the straightening plane. This is explained again in greater detail below using examples.
A method variant which is schematically illustrated in
The horizontally displaceable rollers 514-1 and 514-2 of the clamping apparatuses act as rotation prevention devices, contact the wire material at two contact locations which are diametrically opposite in the horizontal direction with relatively slight pressure which is sized so that the static friction is sufficient to prevent inherent rotation of the rod about the longitudinal axis thereof but, at the same time, the wire rod can relax so that it is otherwise free from forces except for gravitational force and consequently has the residual curvatures which are intended to be measured.
With reference to
Advantageous measurement units and procedures have been explained by way of using the example of the configuring of a forming machine in the form of a feeding apparatus which forms wire material which is straightened during correct use by the integrated straightening system from wire material which is supplied from a coil and which arrives with varying initial curvature, and which is supplied to a downstream forming machine as “continuous material”. This disclosure is not limited to the specific measurement units, procedures, or other features but contemplates additional variations as would be recognized by those of ordinary skill in the art.
A measurement unit of the type described herein can also be used in other ways.
The straightening system may have precisely two rolling/straightening apparatuses which preferably generate straightening planes which are perpendicular to each other. A straightening system may also have three or four or more rolling/straightening apparatuses. For example, a straightening system may have four straightening apparatuses which are offset by 45° each, which may be an advantageous variant, for example, for straightening round wire.
The forming machine in which the straightening system is integrated may also be a straightening and cutting machine which is configured to straighten wires or other semi-finished materials which can be processed by straightening and which have different cross-sectional sizes and shapes, and then to cut the straightened straightening material to a desired length. The machine then additionally has a length measurement device and a cutting apparatus which can preferably be automatically actuated on the basis of signals of the length measurement device. The measurement unit can then measure the separated straightened rods. The measurement unit does not require to this end any individual cutting device. It may also be a rod manufacturing machine which further has an insulation stripping device in addition to the straightening system, a cutting device and a length measurement device, to remove portions of the insulation from an initial metal material which is surrounded by an insulation layer.
A straightening system may also be integrated in a forming machine which can produce relatively small or large batches of formed parts with a partially complex geometry by suitable forming tools from the straightened straightening material in an automatic production process.
The forming tools necessary for the forming are then connected downstream of the straightening system. The forming machine may be, for example, a bending machine to produce bending parts from wire material, band material or tubular material, or a spring production machine or a wire pin machine for the mass production of screws, nails, rivets or the like. The measurement unit can, for example, be used to measure the wire which is discharged at a wire guide of the respective machine.
Our system can be used for different types of straightening material, particularly for straightening metal wire material or tubular material. The cross-sectional shape of the straightening material may be different, for example, a circular cross section with round material, a profiled and/or polygonal cross section with profiled material, in particular a rectangular cross section with square material. Flat material such as, for example, metal flat bands with a great aspect ratio between the width and height, can also be straightened. The cross-sectional size may also vary. The metal material may be non-coated or may carry a coating, for example, an electrically non-conductive insulation covering made from plastics material.
The linearity test or measurement does not have to be carried out as described in the example. The linearity test may also be carried out automatically by at least one camera. For example, in flat material the linearity can also be checked during the passage with two cameras which are offset by 90°. Particularly with round wires, a camera which rotates about the wire or a laser scanner may be used.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2021 212 059.8 | Oct 2021 | DE | national |
This application is a US national stage filing under 35 U.S.C. § 371 of International Application No. PCT/EP2022/079559, filed Oct. 25, 2022, which claims priority to Japanese Patent Application No. 2021-178486, filed Nov. 1, 2021, each of which is incorporated herein by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/079559 | 10/24/2022 | WO |
