Patent Application
20110048088
The invention relates to a stop device, as described in the preamble of claim 1.
From document WO 03/095125 A1 a stop device is known as the rear stop of a production device for bent workpieces made from sheet blanks, in particular sheet metal blanks, which in a finger support mounts a stop finger that is adjustable linearly in a direction perpendicular to a bending plane, which stop finger is adjusted against the action of a spring arrangement on supplying a workpiece to be subjected to bending deformation from a position of rest into a stop position delimited by a fixed stop. By means of a sensor element the adopted stop position is monitored and by means of a control signal a program sequence is triggered for the shaping process.
From the document U.S. Pat. No. 5,761,940 A1 a method and a device are known as a rear stop of an edging press for the automated feeding of a workpiece to be subjected to bending deformation between bending tools. According to this method and the device stop fingers projecting in the direction of the bending plane are arranged on independent stop supports driven parallel to a bending plane predetermined by the bending tools, on an angle lever pivotable on an axis running perpendicular to a standing surface of the bending press, whereby a stop force causing a pivot movement on the stop finger is measured by means of the force measuring sensor and by evaluating the measurement result in a control and regulating device the workpiece is positioned finally in relation to the bending plane.
The objective of the invention is to create a stop device for a bending press, in particular an edging press, for positioning a workpiece to be shaped between bending tools, in which the adjustment resistance of the stop element can be changed as a function of workpiece parameters.
This objective of the invention is achieved by means of the features described in the characterising part of claim 1. The surprising advantage in this case is that in this way at the same time as automatically configuring the stop device according to predetermined parameters for the shaping process of the predetermined workpiece there is an adjustment of the workpiece-dependent adjustment resistance of the stop element, whereby a manual refitting process becomes unnecessary and incorrect manipulations are effectively avoided.
Embodiments according to claims 2 and 3 are advantageous, by means of which variants of the design are achieved.
Further advantageous embodiments are described in claims 4 to 6, by means of which the workpiece to be shaped is positioned to the limit stop in two dimensions with high precision for high quality shaping.
The embodiments according to claims 7 and 8 are advantageous, by means of which a high degree of automation and thereby a reduction in the effort of refitting is achieved.
By means of the advantageous development described in claim 9 an additional adjustment is made possible at the time of the initial start-up.
By means of the advantageous developments described in claims 10 to 12, a combination of the retaining device with the mechanical adjusting device formed by the spring arrangement is achieved for returning the stop element from a stop position into a position of rest.
Furthermore, an embodiment according to claim 13 is also advantageous, by means of which a very small configuration of the stop device is achieved.
The advantageous developments according to claims 14 and 15 simplify the design of the stop element and in this way the workpiece is positioned precisely for the shaping process.
According to the embodiments described in claims 16 to 20 a fine adjustment is possible of the position of rest and stop position, affecting both the linear adjustment of the stop element and the pivoting adjustment, by means of a single fine positioning at the time of the initial start-up, as well as a pivot movement an increased resistance can be set to an adjustment range by at least one retaining means in order to avoid an unintentional pivoting movement.
According to the advantageous development described in 21 the pivotal position is monitored.
Lastly, the developments according to claims 22 and 23 are advantageous, by means of which an exact delimitation of all end positions is achieved and a final adjustment is ensured by means of fine adjustment.
For a better understanding of the invention the latter is explained in more detail with reference to the exemplary embodiments shown in the Figures.
First of all, it should be noted that in the variously described exemplary embodiments the same parts have been given the same reference numerals and the same component names, whereby the disclosures contained throughout the entire description can be applied to the same parts with the same reference numerals and same component names. Also details relating to position used in the description, such as e.g. top, bottom, side etc. relate to the currently described and represented figure and in case of a change in position should be adjusted to the new position. Furthermore, also individual features or combinations of features from the various exemplary embodiments shown and described can represent in themselves independent or inventive solutions.
In
The stop device 1 forms a so-called rear stop, which in the insertion direction of the workpiece 6—according to arrow 7—is arranged adjustably behind a bending plane 8 defined by the position of the bending tools 4, 5 in a press chamber 9, preferably in three dimensions—according to double arrow 10.
In this way the stop device 1 can be adjusted into the required position according to the fitting of the table bar 2 and bending bar 3, whereby for the adjustment not shown drive devices and control means are provided and the positioning takes place automatically many times by means of the programme sequence for each different bending process.
The stop device 1 consists of a stop support slide 13 which can be driven on a linear guide 12, on which a stop support 14 is secured projecting in the direction of the bending plane 8 and which in a linear guiding arrangement 15 adjustably mounts a stop element 16 in a direction perpendicular to the bending plane 8—according to double arrow 17—between a front position of rest delimited by a stop means 18 and a rear stop position delimited by a stop means 19.
In the exemplary embodiment shown the stop element 15 is after the insertion of the workpiece 6 against the action of a spring arrangement 21 formed by a compression spring 20, in its stop position on the stop means 19, which forms an adjustable fixed stop. The workpiece 6 is pushed for this during the insertion process against a bearing face 22 of the stop element 15 with an end face 23 until the stop position is reached. In this way the end face 23 is aligned precisely in a stop plane 24 running parallel to the bending plane 8 in order to perform the bending deformation on the workpiece 6 exactly parallel to the end face 23.
An end section 25 of the stop element 15 facing the bending plane 8 is graduated in a step-like manner, whereby a bearing surface 26 aligned perpendicular to the bending plane 8 is formed on the stop element 15. At right angles thereto is a further bearing surface 25 lying closer to the bending plane 8 for stopping the workpiece 6, which is used when the end face 23 projects only slightly over the bending tool 4.
The stop support 14 comprises in a recess formed between the guiding arrangements 16 a sensor element 27, i.e. a proximity sensor, which with an end face 28 faces an end face 29 of the a base part 30 of the stop element 15, so that the adopted stop position of the stop element 15 is detected. Preferably, the sensor element 27 is secured adjustably in the direction of adjustment according to double arrow 15—of the stop element 15 on the stop support 14.
Furthermore, in the recess a retaining device 31, consisting of a magnetic coil 33 chargeable with electrical energy from an energy source 32, is arranged with a bolt-like coil armature core 34, which passes through the magnet coil 33 in a bore 36 with a cylinder pin 37 and with the base part 30 of the stop element 15 comprises a pressure head 38 cooperating with the end face. Between the pressure head 38 and the magnet coil 33 the cylinder pin 37 is surrounded by the pretensioned compression spring 20, whereby the stop element 15 in a position of rest is positioned in a front position of rest facing the bending plane 8.
The cylinder pin 37 has at one end 39 opposite the pressure head 38 a support flange 40, on which as soon as a magnetic field is produced, bears on an end face 41 of the magnetic coil 33 and thus depending on the magnetic field strength opposes a variable resistance of a movement of the coil armature core 34 and thus a movement of the stop element 15.
Also by means of an annular ring surface projecting over the cylinder pin 37 the coil armature core 34 is supported on the end face 41 of the magnet coil 33 and thus an adjustment path of the stop element 15 is determined via the fixed front end position owing to the effect of the compression spring 20 in addition to the stop means 18.
By means of the retaining device 31 formed by the magnet coil 33 and the coil armatures 37 on the one hand resistance opposing a stop movement of the stop element—according to arrow 42—can be controlled by the pretensioning force of the compression spring 20 and also if necessary by charging the magnet coil 33 with current from the energy source 32, whereby the magnetic field strength can be controlled by changing the current strength or the voltage.
Thus depending on a frictional force of adjusted resistant acting on the nature of the workpiece 6 on the stepping of the stop element 15, when inserting the workpiece 6, an adjustment of the stop element 15—according to arrow 42—is opposed, and thus an adjustment of the stop element 15 is effectively prevented, before the workpiece 6 comes to bear with its end face 23 on the bearing surface 22, even in the case of a heavy workpiece 6 or with a high coefficient of friction caused by a rough surface of the workpiece. If however light workpieces or workpieces with sliding surfaces, in particular thin, blank metal sheets are subjected to the bending process the action of the retaining device can be dispensed with.
The described stop device is used as a so-called fixed stop for aligning the end face 23 of the workpiece 6 on supplying along an X-axis, whereby the stop element 15 in the stop position is adjusted against the stop means, at which a defined spacing 43 of the bending plane 8 from the stop plane 24 is achieved. This is monitored by the sensor element 27 by means of which on establishing the reached stop position of the stop element 15 a control signal at a control device of the edging press is started for introducing the shaping process by controlling the drive means of the edging press.
As the spacing 43 depending on the workpiece 6 and thus a provided edging height has a different size, but a distance 44 between the stop plane in the inserted state of the stop element 15 and a longitudinal central axis of the linear guide 12 has structural predefined size, the linear guide 12, on which the stop support slide 13 is arranged adjustably—according to double arrow 10—in a direction perpendicular to the bending plane 8—according to arrow 10.
Also a further design of a fixed stop 47 between the stop element 15 and the stop support 14 is shown by broken lines, which is formed in that a finger section 48 of the stop element 15 has a greater width 49, than a width 50 of the stop support 14, whereby opposite end faces 51, 52 of the finger section 48 and the stop support 14 form said fixed stop 47, which in this shown exemplary embodiment is not adjustable, unlike the exemplary embodiment with the fixed stop 19 described above.
It should also be mentioned that the stop device 1 described above with workpieces 6 with a greater expansion on the edging press are used in pairs, in order to achieve a greater support width between the stop elements 15. With such an arrangement the sensor elements 27 of the parallel aligned stop devices 1 are used for a final adjustment of the workpiece 6, for example on a gripper head of a handling axis for positioning the end face 23 of the workpiece 6 exactly parallel to the bending plane 8. If the end face 23 is moved in an oblique position to the bending plane 8 against the end stop, for example only by a sensor element 27, a signal is sent to the control device of the edging press and the position is corrected by a rotational movement of the gripper head until there is a signal of the sensor element 27 of the further stop device 1. Once this position has been reached there is an adjustment in the direction of the X-axis to the end stop.
In
For both dimensions the stop element 15 can be adjusted independently from the position of rest into the stop position. In the direction of the X-axis the stop element 15 is adjustable substantially in a direction perpendicular to the bending plane 8 in the guiding arrangement 16, which is formed for example by a linear guiding element 59, e.g. flat track, sliding guide, round rod guiding or recirculating ball guiding element etc. In the direction of the Z-axis the adjustability is achieved by mounting the guiding arrangement 16 or the guiding element 59 in a pivot bearing arrangement 60 on the stop support 14. A pivot axis 61 of the pivot bearing arrangement 60 thus runs parallel to the bending plane 8 and perpendicular to the bearing surface 26 for the workpiece 6 in the finger section 48 of the stop element 15.
In both dimensions the stop position is indicated by fixed stops 62, which can be formed for example by a delimitation of a guiding length of the guiding arrangement 16 or can be adjustable, e.g. by means of adjusting screws.
As already described in the preceding examples, the stop positions, as well as the linear adjustment and also the pivot adjustment are monitored by sensor elements 27, e.g. proximity sensors and form reference values for the position of the workpiece 6, which are stored in the control and monitoring device of the edging press or a data memory.
For the linear adjustment in addition to the spring arrangement 21 formed by the compression spring 20, by means of which the stop element 15 is positioned in the position of rest, and which produces a first adjustment resistance, for increasing the adjustment resistance if necessary the retaining device 31 already described in the preceding Figures is provided with the magnet coil 33 and the coil-armature core 34.
For the pivoting movement also in addition to a compression spring 20, for example in connection with a stop means, a spring arrangement 63 is provided as the retaining device 64, which increases the adjustment resistance if necessary.
The latter consists of pressure bolt 67 which is spring-loaded by a compression spring 66 acting on the pivotable guiding arrangement 16 or a pivot base 65 comprising the guiding element 59, whereby the spring force of the compression spring 66 can be adjusted by means of an adjusting screw 68.
According to a further exemplary embodiment said retaining device 64, can be used in a tandem design, with two parallel pressure bolts 67 and one compression spring 66 respectively, thus achieving a multi-stage adjustment of the adjusting resistance e.g. in three stages if compression springs of varying strength are used.
It is also noted that said described stop device 1, with the possibility of stopping in two dimensions, is preferably used on a bending press in pairs for positioning the workpiece 6 on a bending press and that the stop device is preferably positioned automatically. By being used in pairs usually the workpiece 6 is aligned in the so-called Z-axis only on one of the stop devices 1, whereby in the X-axis both are used, and from the measurement results of the sensor elements 27 an exact alignment of the workpiece 6 in relation to a given bending line is achieved which does not necessarily need to run parallel to the bending plane 8.
All of the details relating to value ranges in the present description are defined such that the latter include any and all part ranges, e.g. a range of 1 to 10 means that all part ranges, starting from the lower limit of 1 to the upper limit 10 are included, i.e. the whole part range beginning with a lower limit of 1 or above and ending at an upper limit of 10 or below, e.g. 1 to 1.7, or 3.2 to 8.1 or 5.5 to 10.
The exemplary embodiments show possible embodiment variants of the stop device, whereby it should be noted at this point that the invention is not restricted to the embodiment variants shown in detail, but rather various different combinations of the individual embodiment variants are possible and this variability, due to the teaching on technical procedure, lies within the ability of a person skilled in the art in this technical field. Thus all conceivable embodiment variants, which are made possible by combining individual details of the embodiment variants shown and described, are also covered by the scope of protection.
Finally, as a point of formality, it should be noted that for a better understanding of the structure of the stop device the latter and its components have not been represented true to scale in part and/or have been enlarged and/or reduced in size.
The underlying problem of the independent solutions according to the invention can be taken from the description.
Mainly the individual embodiments shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| A 1259/2006 | Jul 2006 | AT | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/AT2007/000358 | 7/24/2007 | WO | 00 | 6/28/2010 |
