Patent Application
20230050064
This application claims priority to German Patent Application Number DE 20 2021 104 136.6 filed on Aug. 3, 2021, the content of which is incorporated herein by reference in its entirety.
The invention relates to a low-cost automation quick-change component store for workpieces which are mounted in stacking columns on top of one another or on pawls or next to one another, as well as a corresponding system for presenting workpieces and a stacking column for storing workpieces and a pawl for placing workpieces on top of one another or on top of one another for use in stacking columns.
Stacking columns are known in various forms and designs, and are commercially available. As a rule, they serve to receive stored goods, in particular body parts, e.g. after their production in a press, and to transport them to further processing stations.
The function of the stacking columns is usually the same. If the workpiece to be stored is introduced into a frame made up of several stacking columns, the lowest pawl lever pivots into a working position when the shaped pieces are in contact, wherein the pawl levers each take a following pawl lever from a rest position into a ready position. The next shaped piece to be introduced brings the following pawl lever from the ready position into the working position, in which the pawls hold the shaped piece and pivot the following pawl into the ready position.
In most cases, these are vertical stacking columns, wherein the basic idea of the entrainment of the individual pawl levers or pawls is being shown in DE 38 11 310 C2. Two-armed pawl levers are rotatably mounted one above the other on columns, each of which has a supporting arm, which receives a stock, and a control arm, and can be pivoted out of a rest position via a standby position into a working position and back again, a pawl lever, which is located in the standby position, passing into its working position when a stock is placed on it and, at the same time, a pawl lever, which is arranged above it, is being pivoted by the control arm of the pawl lever arriving in working position out of a rest position into its standby position, wherein the pawl levers, which are in working position, lock one another in this position.
These stacking columns have proven to be excellent in practice. However, in order to store workpieces, a plurality of stacking columns or similar holding devices must interact, which is usually done by constructing a plurality of stacking columns on a frame which is moved, for example, by means of a lifting stacker. In today's degree of automation in the production of workpieces, in particular in the automotive industry, the movement of workpieces usually takes place by means of robots, so that the exact alignment of the stacking column with respect to the robot is essential for the use of stacking columns. The stacking columns must have a constant vertical alignment and a constant spacing from one another so that parts to be stored or removed can be properly accommodated on the latches. It is therefore very difficult and time-consuming to construct a rack on site or to displace it, since the individual stacking columns must be aligned precisely. Even a deviation in the millimetre range when placed on a substrate causes a deviation in the centimetre range in the upper part of the stacking column. Above all, the inclination of stacking columns facing one another with their latches is also essential. As a rule, the construction of such a frame requires just as much time as the production of the entire frame.
The task of the present invention is to provide a component store, a system, a stacking column as well as a latch which can be handled extremely flexibly and whose alignment is simple and extremely precise.
The solution is firstly that the stacking columns are arranged on a mobile carriage.
These components are intended to be used in particular in the production of bodywork components, in particular from sheet metal, in injection moulding for metal inserts and as buffer storage for welding installations and machining centres. But these are just examples. A multiplicity of possible applications are conceivable and are to be comprised in the present invention.
The invention substantially simplifies the handling of the component store, since it can also be moved by hand. A fork-lift truck is not necessary any more, as a result of which the risk of damage to the stacking column or even to the workpieces stored therein is minimized. Of course, the present invention also comprises the fact that the component store can be moved not by hand, but by a tractor, a rail vehicle or even self-propelled. Everything is possible here.
In a simple exemplary embodiment, the movable carriage consists of a base frame which can be moved on rollers. In this case, two rollers are preferably designed to be steerable, while the other two rollers can be stationary. This also supports the mobility of the carriage.
The carriage is preferably assigned a fixing device which corresponds to a parking brake. In other words, instead of a separate locking device, a braking device could also be assigned to at least one pair of wheels. For the sake of simplicity, however, the fixing device here has a fixing foot which can be lowered via a lever mechanism.
This component store can be used solely for the movement of workpieces, but, in an extension of the present invention, it is intended to be part of an overall system with which, in particular, the component store is adjusted with the utmost precision with respect to loading and unloading robots. That is to say, according to the invention, the carriage is assigned a coordinate system which is preferably arranged fixedly, for example on a floor. This coordinate system provides, on the one hand, guide rollers for the component store and, on the other hand, roller blocks for its vertical levelling. The orientation of the component store in x and y direction should be standard, the orientation in z direction should be optional. Furthermore, a centring unit with corresponding roller guides is provided, which cooperates with a centring blade on the component store. This results in the most accurate alignment of the component store in the three coordinates of space; furthermore, the component store is also fixed in the centring unit by means of a variable tensioner.
According to the invention, it is contemplated to always use two carriages of identical construction in automation. In this way, a removal robot can always remove workpieces from a component store, while the other component store is refilled in the meantime. The automation/ system can thus run through without interruption. In the case of a workpiece change, the two component stores can be replaced by other component stores which are equipped for the new workpiece.
Since, as a rule, a plurality of stacking columns are provided on the component store which can also be equipped with different workpieces, it has proven advisable to improve the accessibility of the individual stacking columns. This is achieved in that at least a part of the stacking columns consists of two parts which are connected to one another in an articulated manner. That is to say, one part can be folded down with respect to the other part, so that the space behind this stacking column is thereby accessible. If the folded-down stacking column is then required, it can be erected again and fixed by appropriate clamping levers.
A further idea of the present invention relates to the pawl itself, since it proves advisable for some sensitive components to minimize the contact surface between the pawl and the workpiece. According to the invention, this is accomplished in that a point-shaped support for the workpiece is applied to the support surface of the pawl, which can be done, for example, by means of a flexible hemisphere. Here, too, many possibilities are conceivable which are to be comprised by the present invention.
These special latches are primarily intended for components made of aluminium.
The particular advantage of the present component store is that a large number of workpieces/components can be provided in a small space with a high degree of accuracy for automated handling.
Further advantages, features and details of the invention will be apparent from the following description of preferred embodiments and from the drawings; these show in:
According to
This carriage 1 has a base frame 3 on which lies a plate 4. Stacking columns 5 protrude from the plate 4. At the front, that is to say from the side of the workers, the protective plate 6, on which a handle 7 is arranged, strikes against the carriage 1. The fixing device 8, which is described in greater detail in
A left and a right levelling block 9 and 10, respectively, are provided on the end faces of the frames 3 opposite the fixing device 8.
According to
The system according to the invention for presenting workpieces includes, on the one hand, according to
The centring unit 16 cooperates with a centring blade 19 which is arranged on the floor of the carriage 1. Furthermore, according to
Furthermore, a variable tensioner 24 is provided on the base plate 20.
According to
Apart from that, a plurality of pawls 28 are located in the stacking column 5, which pawls can be rotated around an axis 29 from a rest position into a standby position and then into a working position, as is known from the prior art. For this purpose, they are connected to one another via a corresponding actuating line 20.
In order to connect the two parts 25.1 and 25.2 in vertical alignment, commercially available clamping levers 31.1 and 31.2 are provided according to
In a pawl 28 according to the invention, a point-shaped support 35 is to be provided on a receiving surface 34 for supporting the workpiece, as shown in
The mode of operation of the present invention is as follows:
A component store P, as shown in
As soon as the component store P has been correspondingly loaded, it is moved away by the manufacturer WS and, for example, delivered to a further machining station for the workpieces. There, the workpieces can again be removed by a robot and transferred to a machining station.
For the most accurate centring possible of the component store P with respect to both the loading robot and the unloading robot, the component store P moves with its centring sword 19 into the centring unit 16 of the corresponding coordinate system K, with a corresponding coordinate system K preferably being assigned to both the loading robot and the unloading robot. The cam rollers 22.1 to 22.4 in cooperation with the guide rollers 17.1 and 17.2 align the component store P in its horizontal position and fix it by the variable tensioner 24. This variable tensioner 24 has, for example, a lever which can be rotated around an axis by a corresponding pneumatic device. When the carriage travels over it, this lever lies in the horizontal and is then pivoted into the vertical, it striking, for example, a transverse tube below the carriage and being able to press the carriage, for example, against the roller blocks 18.1 and 18.2. Of course, other stops are also conceivable. In this way, the component store P is secured. The alignment in vertical position is done by the levelling roller 23 and the two roller blocks 18.1 and 18.2, which cooperate with the levelling blocks 9 and 10 of the component storage unit P.
A further fixing of the component store P is then effected by actuating the fixing device 8 and by lowering the fixing foot 40.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20 2021 104 136.6 | Aug 2021 | DE | national |
