Methods for transferring products and suitable transfer robots

Abstract

Gripping head (20) for attachment to a transfer robot (1) and for picking up and holding two products (P) with - a base body (20A), - at least two grippers (22), in particular suction cups (22), which - the suction cup distance (SA) to each other and / or to the base body (20A) is adjustable in a controlled manner, - are arranged on the base body (20A) so as to be rotatable about their vertical axes, the suction vertical axes (22'), - a fastening device (20B) for fastening the gripping head (20) to a supporting component, characterized in that the gripping head (20) is designed such that with only one controlled coupling (28) per gripper (22) and only one controlled drive - both the suction cup distance (SA) - as well as the rotational position of each gripper (22) around the respective suction cup vertical axis (22') can be automatically adjusted.

Description

I. Area of ​​application

[0001] The invention relates to a method for quickly picking up and in particular also depositing, i.e. overall transferring, products as well as a transfer robot suitable for this purpose, and in particular its gripper. II. Technical background

[0002] In industry, robots are used that have one or more grippers as tools with which products are moved.

[0003] On the one hand, there are several fundamentally different designs of such transfer robots: The so-called serial robot is the classic SCARA robot, in which the robot arm consists of several serially successive, articulated arm parts, such as - in reference to the biological arm - robot base or shoulder, upper arm, forearm and robot hand, which are articulated together, whereby the robot hand usually represents the tool or the tool holder.

[0004] Such a serial robot has a relatively large working range and, depending on its design, can also move heavy loads compared to its own weight, but its speed is limited by its own weight and the acceleration power required for this.

[0005] Robots with so-called parallel kinematics, often in the form of tripod robots or so-called delta robots, usually have smaller masses to be moved and are suitable for moving relatively small loads very quickly, but in a relatively small working area compared to the dimensions of such a robot.

[0006] While a transfer robot usually has only a single gripper, e.g. a suction cup, as the gripping head, which can usually only pick up a single product - in exceptional cases, for example, several products stacked on top of each other at once - robots are also known for special applications in which the gripping head has several grippers, each of which can pick up a product and whose relative distance to one another can be changed, which is referred to as spreading of the grippers.

[0007] Since each gripper of the gripping head usually picks up one product after the other before the gripping head is moved to the storage side, this should reduce the time required to transfer a product.

[0008] However, this is only the case if the time required to move the gripper head from the pick-up side to the deposit side, which is distributed over several products in this procedure, is relatively long, i.e., for example, the corresponding path is relatively long in relation to the duration of the individual pick-up processes on the pick-up side.

[0009] If this is possible not only in one but in two spatial directions - preferably viewed from above onto the surface on which the products are presented - this is referred to as cross-spreading.

[0010] However, such applications generally require the special requirement that the products to be picked up are not presented in a completely random manner, but rather, viewed from above, are presented in an orderly manner in at least one dimension or even both dimensions. Thus, again preferably viewed from above, the gripper pattern to be created for picking—that is, the relative position of the grippers to each other within the gripper head—is always the same, at least in one horizontal spatial direction, depending on the picking pattern, which simplifies control.

[0011] A further distinction must be made as to whether the products to be handled are viewed under supervision - are either rotationally symmetrical and / or their rotational position around the vertical axis is not relevant for the transfer process - or the products are not rotationally symmetrical when viewed from above and / or require a specific rotational position around the vertical axis when picking up and / or placing down, because then, as a rule, a controlled rotation of each individual gripper around its vertical axis is necessary as an additional controllable axis, which represents a significantly more complex situation in terms of process technology.

[0012] In this context, a method is known from DE 10 2019 113 287 A1, how a particularly rapid gripping and transfer of products can be carried out by means of a gripping head which has several grippers, usually suction cups, which are adjustable in their mutual distance and arranged in a line and, if necessary, rotatable about their vertical axis.

[0013] However, the multiple controllable grippers increase the weight of the gripper head, which has to be accelerated during each approach process, so that the time required for travel movements increases with increasing weight at the same drive power, since the achievable acceleration decreases.

[0014] An accelerated transfer process can therefore only be achieved if the extension of the travel times caused by the additional weight due to the multiple grippers on the gripping head is more than compensated by the increased number of gripped products per transfer process.

[0015] Whether this is achieved depends largely on whether the additional weight can be kept to a minimum.

[0016] A gripping head according to the invention requires 5 controllable axes, i.e. 5 degrees of freedom, and is particularly suitable and intended for use on a robot with a parallel kinematics.

[0017] The patent specifications or patent applications DE 698 33 909 T2, EP 3639988 A1, WO 2021 / 198058 A1, JP 2000 - 135631 A, JP H09 - 131685 A and JP H06 - 143173 A each show gripping heads with several grippers, in particular in the form of suction cups. III. Description of the inventiona) Technical problem

[0018] The object of the invention is therefore to provide a gripping head for simultaneously transferring two randomly presented products, with which transfer is faster than with a gripping head with only a single gripper, while only slightly increasing the weight of the gripping head. The object is further to provide a method for operating such a gripping head. b) Solution to the task

[0019] This object is achieved by the features of claims 1, 11 and 13. Advantageous embodiments emerge from the subclaims.

[0020] With regard to the gripping head, this object is achieved in that its gripping head is designed such that the grippers can be adjusted in a controlled manner in their relative position to one another and / or in their relative position to the gripping head, in particular a reference point of the gripping head.

[0021] Since suction cups that can be acted upon by means of negative pressure are usually used as grippers, the terms suction cup and gripper are used synonymously in the present description, without restricting the invention to suction cups as grippers, i.e. without excluding other types of grippers than suction cups.

[0022] Preferably, when viewed from above, all grippers, in particular their centers, and in the case of grippers that can be rotated about the vertical axis, their vertical axes, lie on a common line that defines the adjustment direction, in that the suction cups can only be adjusted in a controlled manner along this line.

[0023] Preferably, the suction cups are linearly movable for this purpose, and the line is a straight line. Preferably, at least one of the two grippers is linearly movable relative to the other along the adjustment direction.

[0024] Alternatively, the suction cups can each be pivoted relative to the gripping head about a pivot axis located at a distance from the center of the suction cup, whereby the pivot axis of all suction cups can be the same.

[0025] The center of a suction cup, viewed from above, is understood to be the geometric center of a round or regularly polygonal gripper or suction cup, and the position of this vertical axis viewed from above of a suction cup that can be rotated about a vertical axis, in particular at the level of the gripping plane, in particular the receiving surface of the product to be picked up, otherwise the center of gravity of the surface of the suction cup.

[0026] Preferably, the gripper head is designed such that the distance between all grippers in the adjustment direction can only be adjusted synchronously and / or can only be adjusted in such a way that any two adjacent robots can only ever be adjusted synchronously in their distances, and the distances between the adjacent pairs of robots are always the same.

[0027] In a preferred embodiment, the gripping head comprises precisely two grippers, in particular suction cups, whose distance from each other and / or from a reference point of the gripping head can be adjusted in a controlled manner when viewed from above. This minimizes the control effort required for the gripping head.

[0028] The suction cups are preferably rotatable in their rotational position relative to the gripping head around vertical axes, in particular individually and independently of one another.

[0029] However, to reduce the control effort, it is also possible to design the gripping head in such a way that all suction cups or a part of the suction cups of a gripping head can only be rotated synchronously with each other around their vertical axes.

[0030] This makes it possible - possibly with more time expenditure for delayed picking and / or depositing - to deposit products transported by the gripper head in the depositing area not only in a predetermined depositing pattern, but also for each product with the target rotational position provided at its depositing position.

[0031] Specifically, the task is solved with a generic gripper head - which has a base body and two grippers, usually suction cups, whose suction cup spacing is adjustable and which can also be rotated in a controlled manner about their vertical axes - in that the gripper head is designed in such a way that with only one controlled drive and at least one coupling, both the suction cup spacing and the rotational position of each gripper, in particular suction cup, about the respective gripper vertical axis can be automatically adjusted.

[0032] This means that only one controlled axis, i.e. one controlled parameter, is required, and this control can be supplied to the gripper head, after it is attached to a robot arm, via the robot arm and the fastening device on the robot arm.

[0033] In particular, the gripper head with the multiple grippers or suction cups can be replaced with a single suction cup attached to the robot or robot arm.

[0034] The gripping head has a spacer pinion which is rotatably mounted, for example in the base body, and which engages with two racks which are usually arranged on two opposite sides of the spacer pinion.

[0035] A suction cup base body is attached to each of the racks at a fixed axial position, so that the two suction cup base bodies are opposite each other with respect to the rotational axis of the spacer pinion and can be driven counter-synchronously toward or away from the spacer pinion, the spacing direction, thereby adjusting the suction cup spacing. For stabilization, the suction cup base bodies can also be guided along a guide, preferably a common one, in the spacing direction.

[0036] The spacer pinion is preferably driven externally from the gripper head, usually from the robot or robot arm to which the gripper head is attached.

[0037] In order to be able to adjust the rotational position around the vertical axis for each suction cup separately in adaptation to the product to be picked up, a suction tube is mounted around the vertical axis of this suction cup in each suction cup base body, with the actual suction cup being located at the lower end of the suction tube.

[0038] Concentric to each suction tube there is a drive sleeve which can be driven rotatably about its longitudinal axis, the vertical axis, by means of circumferential teeth on its outer circumference, preferably in its upper end area.

[0039] The circumferential toothing of these drive sleeves of all suction units engages with a rack, in particular a double-toothed rack, which runs in particular parallel to the racks for the distance adjustment, but viewed from above between the suction drive sleeves and thus also the suction base body arranged concentrically thereto.

[0040] When adjusting the distance between the two suction cups, the drive sleeves roll along the double rack and rotate. If the suction tube is connected to the drive sleeve in a rotationally fixed manner, the suction tube also rotates and changes its rotational position.

[0041] In order to be able to control this, a switchable coupling, in particular one each, is arranged between the drive sleeve and the suction tube or between the base body and the suction tube to connect these two elements in a rotationally fixed manner.

[0042] This means that while the suction cup distance is changed, a suction cup tube can be rotated until it has reached the desired rotational position around the vertical axis, and then by deactivating the rotationally fixed connection between the suction cup tube and the drive sleeve and / or locking the rotational position, this rotational position can be maintained, while with further distance changes the drive sleeve naturally continues to roll on the double rack.

[0043] Therefore, the coupling preferably includes a locking device for locking the suction tube in a current, desired, rotational position. This can be achieved by force-locking or positive locking by holding the suction tube in the current rotational position.

[0044] A first, very simple and yet form-fitting possibility is that, in particular concentric to the vertical axis, a locking pin projects upwards from the suction tube, which has a polygonal, preferably regularly hexagonal, cross-section, in particular at its upper free end.

[0045] Above this, a locking sleeve is arranged which can be adjusted in height and brought into engagement with the locking pin by lowering it. By being placed on the locking pin, this sleeve prevents further rotation, in particular in a form-fitting manner, since it is fixed in a rotationally fixed manner, for example, to the base body and can only be moved axially to the locking pin.

[0046] This locking sleeve can, for example, be a so-called universal nut, which is known per se, in which the inner hexagon space of a very large nut, in particular an internal hexagon, is filled with a plurality of adjacent pins, in particular hexagon pins, which each have an outer circumference in the form of a regular hexagon and all have the same size.

[0047] The pins, especially hexagon pins, are individually pre-tensioned in the extended direction by means of spring force and in this extended direction their front free end ends approximately at the front free end of the internal hexagon space.

[0048] If such a universal nut is placed on a polygonal head, for example a hexagon screw head, the pins located in the surface area of ​​the head are pushed into the universal nut against the force of the pre-tensioning spring, but the hexagon pins arranged around the hexagon screw head or in this case the hexagon pin rest both on the hexagon pin and on each other in a form-fitting manner and prevent rotation of the hexagon pin or a hexagon screw head relative to the universal nut, regardless of its size, its specific circumferential design and also a centric or eccentric position relative to the universal nut.

[0049] Preferably, the suction tube is connected to the drive sleeve in a limited, non-rotatable manner, but when the rotational movement of the suction tube is locked, this non-rotatable connection is overcome, so that the suction tube is held in place in a non-rotatable manner and the drive sleeve can continue to rotate due to its rolling on the double rack.

[0050] With regard to the turnover robot, which generically comprises a robot arm and a gripping head attached to its free end in a controlled manner so as to be rotatable about a vertical axis, this object is achieved in that the gripping head is designed as described above.

[0051] Preferably, the gripping head, in particular its fastening device and the parts of the robot arm that can be engaged therewith, are designed such that by fastening the gripping head to the robot arm, all connections required for the operation of the gripping head, in particular drive connections, are established with the robot arm.

[0052] With regard to the method, this object is achieved in that, before the picking process, i.e. during the approach of the gripping head to the defined picking group of products to be picked up, the gripper pattern in the gripping head is adjusted, at least for some of the grippers, to the picking pattern in which the products of the picking group to be picked up are located in relation to one another.

[0053] This is achieved in the previously described specific design of the gripping head with only two grippers or suction cups, whereby these two are brought to the same distance as the two products to be picked up.

[0054] The relative positions of the products to be picked up in the picking group form a picking pattern, the relative positions of the grippers in the gripping head form a gripper pattern.

[0055] In particular, the number of products in the pick-up group corresponds to the number of grippers in the gripping head.

[0056] In addition - also before picking up the group of products - the gripper head is rotated about a vertical axis in such a way that, when viewed from above, the gripper pattern is at least partially in the same rotational position as the picking pattern, so that it coincides with the latter when the gripper head is above the group of products to be picked up, in particular the gripper pattern is above the picking pattern.

[0057] When the gripping head is then lowered onto the group of products, those grippers of the gripping head, each of which now has a product under them, can pick up such a product, either simultaneously or in quick succession.

[0058] Simultaneous picking is preferable because it not only saves time but also requires only the gripper head to be lowered as a whole, and it does not require each individual gripper to be individually controlled to lower it relative to the gripper head.

[0059] If in this case we are talking about a single product which is gripped by a gripper, this can in individual cases also be a plurality of product parts which comprise such a product, for example a related group of product parts which are gripped and handled together as a product, for example a stack of products.

[0060] Likewise, a product may be so large and / or heavy that it must be held by two or more grippers or suction cups simultaneously. In such a group of grippers or suction cups, the grippers or suction cups are usually always in an unchanged relative position to each other and are considered a single gripper or suction cup within the meaning of the invention.

[0061] As soon as each gripper or suction cup of the gripping head has picked up a product, the gripping head is lifted up and moved away from the picking surface on which the products to be picked up were located, i.e. the picking area, preferably in the direction of the deposit area.

[0062] For the described process, the recording positions of the individual products of the recording group on the recording surface must be known, in particular the relative positions of the products of the recording group to each other, which is usually done by means of a scanner or is already specified from other sources.

[0063] The preferred case according to the invention is that the gripping head comprises only two grippers or suction cups.

[0064] In this case, compared to a gripper head with only a single gripper or suction cup, only one additional controllable axis is required. This is the controllable parameter of the distance of the respective suction cup from a reference point of the gripper head—usually the center of the gripper head between the two suction cups and / or the vertical axis of the gripper head, around which it can be rotated in a controlled manner—which also controls the distance between the two suction cups. Preferably, the two grippers are moved counter-synchronously, especially exclusively counter-synchronously, to this reference point.

[0065] Preferably, the two suction cups, in particular viewed from above, are displaced linearly along a line which preferably runs through the reference point and / or through the centers of the two suction cups, or the two suction cups are each pivoted about a pivot axis and thereby change their distance from one another, wherein preferably the two pivot axes are identical. c) Examples of implementation

[0066] Embodiments of the invention are described in more detail below by way of example. They show: Fig. 1: a plan view of a known robot line with several transfer robots in principle representation, Fig. 2a, b: different views of a known robot arm of a robot from Fig. 1 in principle representation, Fig. 3a - f: different working positions of a gripping head with two grippers for handling rectangular products in plan view, in principle representation, Fig. 4a: a concrete design solution of such a gripping head with two adjustable grippers in a top view with a first design of a blocking device for a suction cup rotatable around the vertical axis, Fig. 4b: a vertical section along the line B - B in Fig. 4a, Fig. 5a: a vertical section through both suction cups in an analogous representation to Fig. 4b with a second design of a blocking device, Fig. 5b: a universal nut, which is part of the locking device of the Fig. 5a is, in front view.

[0067] Fig. 1 shows a known robot line 100 as a transfer device, by means of which products P are delivered in an unordered manner on a receiving surface 101 - here in the form of a moving product belt 101 - and are gripped by one of the several robots 1 arranged one behind the other in the direction of travel 101' of the product belt 101 and are placed on a depositing surface 103 - in this case the bottom of containers 102.

[0068] In this case, the robots 1 are serial robots, so-called SCARA robots, which, however, is irrelevant for the use of the gripper head according to the invention, provided the robot offers a sufficient number of controllable axes. These robots could therefore also be delta robots with a sufficient number of controllable axes.

[0069] For this purpose, at the entrance in front of the transfer area, i.e. in front of the first robot 1 present in the flow direction 101', the position and, if applicable, also the rotational position of the products P on the product belt 101 is determined by means of a scanner 105 and passed on to the controller 100* of the robot line 100, which is also connected to the drives of all other moving components and knows, for example, the speed of the product belt 101 in the flow direction 101', so that the absolute product positions of the products P on the product belt 101 are known at all times, if applicable including their rotational position.

[0070] The containers 102 are located on one of, in this case, two container belts 106, which in this case run parallel to, but opposite to, the flow direction 101', each laterally next to the product belt 101.

[0071] Of the robots 1, the crossbeams 104, which run above the product belt 101 in the horizontal transverse direction to the flow direction 101' and are usually mounted, can be seen. These crossbeams serve as the robot base 104 and to each of which a - in this case serial - robot arm is attached.

[0072] Its upper arm 2 is pivotable relative to the robot base 104 about an upper arm axis 2' extending in the vertical 10 in the horizontal plane, and likewise a lower arm 3, which is pivotably attached about an upright, in particular vertical, lower arm axis 3' at the free end of the upper arm 2.

[0073] At the free end of the lower arm 3, a lifting unit 4 is attached, which causes the vertical movement of a gripping head 20 fastened to its lower end, which has at least one gripper 22, in particular suction cup 22.

[0074] The Fig. 2a, b show the side view of the Fig. 2a and the supervision of the Fig. 2b shows, by way of example, a design of the lifting unit 4 on a robot arm with upper arm 2 and lower arm 3, which is only shown schematically, in which a lifting column 5, at the lower end of which a gripping head 20 with only one suction cup 22 is arranged, which can be moved in a controlled manner in the vertical 10 relative to a guide sleeve 6 by means of a finite toothed belt 8 which acts on the lifting column 5 and also runs vertically.

[0075] The toothed belt 8 also runs in the direction of the vertical 10 and is fastened with its two fastening ends 7a, b to the lower and upper end of the lifting column 5 and is operatively connected to a controlled drive pinion which is fastened to the lifting unit 4 at a fixed height position relative to the lower arm 3.

[0076] The lifting column 5 extends vertically through the guide sleeve 6, which is fastened to the lower arm 3 in a fixed height position and is preferably additionally rotatable in a controlled manner about an upright, in particular vertically extending, lifting axis 4', so that the entire lifting column 5 and thus also the gripping head 20 fastened thereto can be rotated about this upright lifting axis 4'.

[0077] In other designs of the lifting unit 4, the gripping head 20 is driven in the vertical direction 10 in a different way and / or only the gripping head 20, for example the suction cup 22, is rotatable about the upright lifting axis 4'.

[0078] Other designs of a lifting unit 4 can also be used within the scope of the present invention.

[0079] In the following described Fig. 3a - f, a gripping head 20 with two grippers 22, in particular suction cups 22, is mounted at the lower end of the lifting unit 4. In the following, only suction cups 22 are referred to, without limiting the grippers 22 to this single design.

[0080] Based on the Fig. 3a to 3e show the transfer of products P which are non-circular in plan view, in this case square, which are transported in an unordered manner on a receiving surface 101 such as a product belt 101, into defined nesting positions in containers 102, the bottoms of which form a storage surface 103, wherein the containers 102 are transported on a container belt 106 which, in this case, is also arranged parallel to the receiving surface 101 in the form of the product belt 101, but in the opposite direction.

[0081] The containers 102 each contain four nest positions in a row, which - as in Fig. 3c - between each two nest positions, i.e. measured from center to center of the nest position, each have a nest distance NA.

[0082] The transfer is carried out by means of a robot arm - from which in the Fig. 3a to 3e only the free end of the lower arm 3 is shown - in particular the gripping head 20 arranged on its lifting unit 4, which is a so-called double picker having two grippers 22 in the form of suction cups 22 which are adjustable along the gripping head 20 between a minimum suction cup distance SAmin and a maximum suction cup distance SAmax.

[0083] The centers of the suction cups 22 move - if they run point-symmetrically to the center of the gripping head viewed in plan view, in particular the spacer pinion 24, on different sides of the double rack 27 - on a straight line 23, which thus represents the adjustment direction 23' of the suction cups 22 and, in this case viewed in plan view, is always in the same rotational position relative to the base body 20A of the gripping head 20.

[0084] In this case, the suction cups 22 always move counter-synchronously to a reference point 9 on the gripping head 20, which also lies on the straight line 23, the line of movement, and is arranged such that it is always in the middle between the two suction cups, regardless of the suction cup distance SA.

[0085] The gripping head 20 is pivotable relative to the lower arm 3 carrying it about an upright gripping head axis 20', which in particular runs in the vertical 10, in the plane perpendicular to the gripping head axis 20', in particular a horizontal plane which is spanned by the two horizontal transverse directions 11.1, 11.2, which in particular run perpendicular to one another, one of which, for example the first transverse direction 11.1, can be defined as corresponding to the passage direction 101' of the product belt 101.

[0086] The gripper head axis 20' is selected so that it not only intersects the movement line 23, but also runs exactly through the reference point 9.

[0087] In addition, the gripping head 20 is displaceable in height, in particular the vertical 10, relative to the component carrying it, in this case the lower arm 3, preferably along the Fig. 2a, b, which in this case coincides with the gripper head axis 20' in order to be able to lift products P picked up by the suction cups 22.

[0088] In order to limit the parameters to be controlled, however, in this design only the gripping head 20 as a whole can be displaced in the stroke direction 4', not the individual suction cups 22 independently of one another. The conversion process is as follows:

[0089] The controller 100* of the robot line 100 first selects, according to criteria stored in the controller, a pick-up group AG consisting of two products P located on the pick-up surface 101, which in this case comprises two products corresponding to the number of two suction cups 22 over which the gripping head 20 according to Fig. 3a, and whose mutual distance between SAmin and SAmax is.

[0090] Subsequently, according to Fig. 3b the two suction cups 22 are moved relative to each other and / or to their reference point 9 on the gripping head 20 such that they assume a suction cup distance SA from each other which corresponds to the pick-up distance AA of the two products P of the selected pick-up group AG.

[0091] Both the pick-up distance AA and the suction cup distance SA are measured from center to center of the products or suction cups.

[0092] Furthermore, the gripping head 20 is rotated about its upright gripping head axis 20' relative to the lower arm 2 such that the adjustment direction 23' of the two suction cups 22 runs parallel to the connecting line between the centers of the two products P of the receiving group AG to be picked up.

[0093] Furthermore, the gripping head 20 is connected to the suction cups 22 according to Fig. 3c positioned exactly above the receiving group AG, i.e. the two selected products P to be picked up, so that after lowering the gripping head 20 and activating, i.e. applying suction air, each of the two suction cups 22 grips, i.e. sucks, one of the two products P to be picked up, wherein the rotational position of each suction cup 22 about its upright suction cup axis 22' is known, as it is usually constantly detected.

[0094] Preferably immediately thereafter, the gripping head 20 is lifted along the lifting axis 4', which here is also the gripping head axis 20', i.e. its height is adjusted relative to the lower arm 3, and the products P located on the suction cups 22 are thus lifted from the receiving surface 101 so that they are at least at a height such that they can be moved over the products P still located on the receiving surface 101 and can also be moved over the edge of the containers 102 into which they are to be deposited.

[0095] Because according to Fig. 3d, the gripping head 20 is moved by means of the robot arm in the direction of the container 102 into which the two products P held by the gripping head 20 are to be placed.

[0096] The containers 102, each having four deposit positions, i.e. nests, are filled successively by filling with two nest groups NG, each comprising two products P corresponding to the number of suction cups of the gripping head 22, in this case a receiving group AG.

[0097] A first nest group NG is already located in the container 102 intended for storage.

[0098] When the gripping head 20 approaches this container 102, the suction cups 22 are brought to a suction cup spacing SA corresponding to the nest spacing NA of the nests to be filled in the containers 102 and the gripping head 20 is rotated about its gripping head axis 20' such that the adjustment direction 23' of its suction cups 22 runs parallel to the line on which the nest positions of the nest group to be deposited, here the entire container 102, are located, since its nest positions are also all on one line.

[0099] Then, according to Fig. 3e the gripping head 20 is positioned above the container 102 in such a way that the two products P held by the gripping head 20 are located above the two still free nest positions of the container 102, and by lowering and subsequently deactivating the suction cups 22, the two products P hanging thereon are deposited as a second nest group NG in the container 102, which is thereby completely filled.

[0100] The gripping head 20 can then be raised again with the now unloaded grippers 22 and the next transfer order can be assigned to it by the controller 100*.

[0101] As the Fig. 3a to f, the products P are to be placed in the containers 102 with their outer edges running parallel to one another, their square shape when viewed from above.

[0102] Therefore, the Fig. 3c, the products P already held on the suction cups 22, which are, however, still in different rotational positions relative to each other - i.e. not yet with their mutually facing outer edges parallel to each other - initially according to Fig. 3d can be brought into such a rotational position - which is why the suction cups can be rotated separately and independently of each other about their suction cup axes 22' - can be brought into the desired rotational position relative to each other.

[0103] This can occur simultaneously with the approach of the gripping head 20 to the container 102 and / or the adjustment of the suction cup distance SA to the nest distance NA.

[0104] Subsequently, the material is deposited in the container 102 according to the Fig. 3e, f as described above.

[0105] The Fig. 4a, b show a first possible constructive solution of a gripping head 20 suitable for the procedure described above: A base body 20A of the gripping head 20 essentially consists of struts running in the greatest extension direction of the gripping head 20, the gripping head axis 20', which are each connected at the end to a front plate or a front frame.

[0106] The base body 20A is designed as a mirror image of its vertical longitudinal center plane 20".

[0107] In the center, i.e. viewed in plan view at half the length of the base body 20A along the longitudinal center plane 20", the base body 20A has a fastening device 33 on its upper side for fastening to the free end of a robot arm 105, for example with a bayonet lock.

[0108] At this point, i.e. in the center, a so-called spacing pinion 24 is rotatable around the vertical, the pinion axis 24', to the top plane of the Fig. 4a with a bearing journal projecting upwards from the spacer pinion 24, so that the spacer pinion 24 is located below the - in Fig. 4a for reasons of clarity not shown - fastening device 33.

[0109] Viewed from above, there is a toothed rack 25a, b opposite each other with respect to the longitudinal center plane 20" running in the direction of the gripping head axis 20', which are additionally arranged point-symmetrically to the pinion axis 24' and which both mesh with the spacer pinion 24.

[0110] Each of the racks 25a, b is guided on a guide rod 32 which also runs in the direction of the gripping head axis 20', wherein the guide rod 32 preferably has a non-circular cross-section in order to prevent the position of the rack 25a, b from twisting relative to the longitudinal axis of the guide rod 32 and to keep the rack 25a, b in engagement with the spacer pinion 24.

[0111] In the end regions of the two racks 25a, b facing away from each other, a gripper, in particular a suction cup 22, is arranged in each case, in which - see Fig. 4b - in this suction base body 22A guided on the guide rod 32, a suction tube 22B is rotatable about a vertical to the top plane of the Fig. 4a standing gripper axis 22' is mounted, in terms of height, usually arranged below the height of the spacer pinion 24.

[0112] By controlled rotation of the spacing pinion 24, the two suction tubes 22B and thus the suction cups 22 attached to their lower ends can be moved synchronously towards and away from each other in the direction of the gripping head axis 20', and thus analogously towards and away from the pinion axis 24' - which generally also serves as the reference point 9 for determining the position of the gripping head 20 in space.

[0113] The movement line 23, which connects the centers of the suction cups 22 viewed in plan view, rotates slightly around the pinion axis 24', ie the acute angle relative to the longitudinal center plane 20" becomes slightly larger when moving towards each other.

[0114] Each of the suction tubes 22B is concentrically surrounded by a drive sleeve 26 and is connected to it in a limited force-locking manner, for example by means of one or two O-rings arranged therebetween or a sliding intermediate sleeve, and in the case of force-locking, is connected in a rotationally fixed manner.

[0115] The drive sleeve 26 carries a toothing 26a on its outer circumference, and these external toothings 26a of the two drive sleeves 26 are in meshing engagement with a double toothed rack 27 which, viewed in plan view, runs fixedly on the longitudinal center plane 20" in the base body 20A, in particular below the spacer pinion 24, and which carries the same toothing on each of the two opposite sides, each facing one of the external toothings 26a, and the external toothings 26a are also preferably identical on both drive sleeves 26.

[0116] However, it could also be a simple rack, and the two external teeth 26a could roll on the same toothing, i.e. side, of this rack.

[0117] The rack with its toothing could also be located away from the longitudinal center plane 20" of the gripping head 20, and the suction cups 22, in particular suction cup tubes 22B, could always be located with their centers on the longitudinal center plane 20".

[0118] This causes the suction tube 22B with the suction cup 22 attached to it to rotate around its upright axis upon rotation of the spacer pinion 24 and relative movement of the two suction cups 22 to each other due to the rolling of the drive sleeve 26 along the double rack 27.

[0119] This is used to bring the suction cup 22 - in particular with a product P held thereon which is non-round when viewed from above - into a desired rotational position about the upright gripper axis 22'.

[0120] In order to prevent further rotation of the suction tube 22B about the gripper axis 22' during the rolling on the double rack 27 when this desired rotational position is reached, despite further rolling of the drive sleeve 26 along the double rack 27, a coupling 28 is provided which holds the suction tube 22B in the desired rotational position, in particular clamps it, and thereby cancels the frictional connection with the further rotating drive sleeve 26.

[0121] The coupling is also attached to the suction cup base body 22A, preferably arranged at the upper end of the suction cup tube 22B, which can protrude upwards from the suction cup base body 22A.

[0122] In the case of Fig. 4b, the coupling 28 comprises two clamping jaws arranged opposite one another with respect to the gripper axis 22', which can be moved towards and away from one another in a controlled manner and, when pressed against one another, clamp a section, here the upper end flange, of the suction tube 22B between them.

[0123] Fig. 5a shows in a similar representation as Fig. 4b and here a slightly differently designed base body 20A as a blocking device instead of this force-locking coupling 28, a form-locking coupling 28.

[0124] A locking pin 29 projects upwards from the upper end of the suction tube 22B, which, when viewed from above, has a non-circular, for example hexagonal, cross-section.

[0125] In the suction cup base body 22A, a locking sleeve 30 is arranged vertically to the top view of the Fig. 4a is displaceable in a controlled manner - the drive for this is not shown for reasons of clarity - but is arranged in a rotationally fixed manner about the vertical, which can be brought into engagement (shown on the right suction cup 22) or out of engagement (shown on the left suction cup 22) with the locking pin 29 by this vertical movement.

[0126] In the activated position, the engaged position, the locking pin 29 and thus the suction tube 22B connected thereto in a rotationally fixed manner are locked, i.e. prevented from further rotating about the vertical, since the locking sleeve 30 in the suction base body 20A cannot be rotated about its vertical axis.

[0127] For this purpose, the locking sleeve 30 preferably has a non-circular, for example also hexagonal, outer circumference, at least in a certain height range.

[0128] A suitable design of such a locking sleeve 30 is a so-called universal nut 30, as used in Fig. 5b in the front view, i.e. in Fig. 5a viewed from below, shows: Such a universal nut 30 has a pot-shaped housing 30a, which in this case is designed according to Fig. 5a is installed with the bottom upwards and the opening downwards in the suction cup base body 22A.

[0129] The interior of the pot-shaped housing, which may, for example, have a hexagonal cross-section, is filled with a plurality of pins 31 running in the axial direction 30' of this sleeve 30, which pins support each other and against the inner circumference of the sleeve 30, but above all each one is supported in the axial direction 30' by means of a compression spring against the bottom of the pot-shaped housing 30a, wherein these compression springs - not shown - pretension the pins 31 into the extended position, in which they all end at approximately the same level with their front free end, approximately in the axial direction in the region of the opening of the pot-shaped housing 30a of the sleeve 30 or slightly set back from this.

[0130] A particularly good form fit can be achieved, for example, if the cross section of the interior of the pot-shaped housing 30a of the nut 30 forms a regular hexagon, as does the cross section of the individual pins 31, which are thus hexagonal pins.

[0131] If such a universal nut 30 is used according to Fig. 5a right side - time-controlled - pressed onto a non-circular locking pin 29, the cross section of which is smaller than the cross section of the interior of the universal nut 30, this pushes the pins 31 lying in its cross-sectional area towards the ground, and is tightly surrounded by the other pins 31 on its circumference, so that the locking pin 29 can no longer rotate relative to the pot-shaped housing 30a of the universal nut 30. LIST OF REFERENCE SYMBOLS 1 robot 2 upper arm 2' upper arm axis 3 Forearm 3' forearm axis 4 lifting unit 4' lifting axis 5 lifting column 6 Guide sleeve 7a, b fastening end 8 timing belts 9 Reference point 10 vertical 11.1 1. Transverse direction, running direction of the receiving surface 11.2 2. Transverse direction 20 gripping head 20A base body 20' gripper head axis 20" longitudinal center plane 21 Tool holder 22 suction cups, grippers 22A suction cup base body 22B Suction tube 22' gripper axis 23 Movement line, straight line 23' Adjustment direction 24 spacer pinions 24' pinion axle 25a, b rack 26 Drive sleeve 26a Circumferential toothing 27 Double rack 28 Clutch 29 locking pins 30 locking sleeve 30a housing 30' axial direction 31 pin, hexagon pin 32 Guide, guide rod 33 Fastening device 100 Transfer device, robot line 100* Control 101 receiving area, product belt 102 containers 103 storage space 104 Crossbeam, robot base 105 scanners 106 Container belt AA shooting distance AG Recording Group SA suction cup distance SAmax maximum suction cup distance SAmin minimum suction cup distance NA Nest distance NG Nest Group P Product

Claims

[1] Gripping head (20) for attachment to a transfer robot (1) and for picking up and holding two products (P) with - a base body (20A), - at least two grippers (22), in particular suction cups (22), which - the suction cup distance (SA) to each other and / or to the base body (20A) is adjustable in a controlled manner, - are arranged on the base body (20A) so as to be rotatable about their vertical axes, the suction vertical axes (22'), - a fastening device (20B) for fastening the gripping head (20) to a supporting component, characterized by that the gripping head (20) is designed so that with only one controlled coupling (28) per gripper (22) and only one controlled drive - both the suction cup distance (SA) - as well as the rotational position of each gripper (22) around the respective suction cup vertical axis (22') can be automatically adjusted. [2] Gripping head according to claim 1, characterized bythat at least one of the two suction cups (22) - either linearly movable along the base body (20A) relative to the other suction cup (22), - or is pivotable about an upright pivot axis running transversely to the distance between the two suction cups (22). [3] Gripping head according to one of the preceding claims, characterized by , that - all suction cups (22) viewed from above lie with their centers, in particular their axes of rotation, on a movement line (23) and are only adjustable in the adjustment direction (23') defined by this line, - in particular the gripping head (20) is designed so that the distance between all suction cups (22) in the adjustment direction (23') can only be adjusted synchronously, and / or - in particular the robot (1) is designed such that the suction cup distances (SA) of adjacent suction cups (22) of the gripping head (20) are always the same size from one another. [4] Gripping head according to one of the preceding claims, characterized by , that - the movement line (23) and thus the adjustment direction (23') viewed from above is rotatable relative to the base body (20A) and / or - which, in particular all, suction cups (22) are either individually and independently controllably rotatable about their suction cup vertical axis (22'). [5] Gripping head according to one of the preceding claims, characterized by , that - the gripping head (20) comprises two, in particular only two, suction cups (22) which, viewed in plan view, are adjustable in a controlled manner in their suction cup spacing (SA) to one another and / or in their spacing to a reference point (9) of the gripping head (20), in particular the center of the fastening device (20B) viewed in plan view. [6] Gripping head according to one of the preceding claims, characterized by , that - a spacer pinion (24) which is rotatable relative to the base body (20A) about an upright rotational axis (24'), in particular the vertical, and which can be driven in a controlled manner is arranged between two racks (25a, 25b) with which it meshes, - on each of which a suction base body (22A) is arranged in a fixed position, in particular opposite one another with respect to the rotation axis (24') of the spacer pinion (24). [7] Gripping head according to one of the preceding claims, characterized by , that - in each suction cup base body (22A) a suction tube (22B), at the lower end of which the suction cup (22) is located, is mounted rotatably about a vertical axis (22'), - concentrically to each suction tube (22B), a rotatable drive sleeve (26) with a circumferential toothing (26a) is arranged on the outer circumference, - the peripheral toothings (26 a) are in engagement with a double toothed rack (27) which is toothed on both sides and runs parallel to the racks between the suction cup base bodies (22A), - between the drive sleeve (26) and the suction tube (22B), or between the base body and the suction tube (22B), a switchable coupling (28), in particular one each, is arranged for the rotationally fixed connection of the two. [8] Gripping head according to one of the preceding claims, characterized by , that - the coupling (28) is a locking device for locking the suction tube (22B) in the current rotational position, - in particular with a locking pin (29) arranged concentrically to the vertical axis (22') and projecting upwards from the suction tube (22B) with a polygonal, in particular regular hexagonal, upper end face and - a locking sleeve (30) mounted on the base body (22A) in a rotationally fixed manner for axially fitting onto the locking pin (29), thereby blocking its rotation. [9] Gripping head according to one of the preceding claims, characterized by , that - the suction tube is (limited) non-positively and rotationally connected to the drive sleeve (26). [10] Gripping head according to one of the preceding claims, characterized by that the locking sleeve (30) is a universal nut (30) whose internal hexagonal space is filled with a plurality of mutually adjacent pins, in particular hexagonal pins (31), which are individually prestressed in the axial direction (30') by means of spring force. [11] Transfer robot (1) for quickly picking up, transporting and depositing randomly presented products (P), with - a robot arm, - a gripping head (20) at the free end of the robot arm, characterized bythat the gripping head (20) is designed according to one of the preceding claims. [12] Robot according to claim 11, characterized by that the gripping head (20), in particular its fastening device (20B) and the parts of the robot arm that can be brought into engagement therewith, are designed in such a way that by fastening the gripping head (20) to the robot arm, all connections required for the operation of the gripping head (20), in particular drive connections, are established with the robot arm. [13] Method for the rapid picking up, transporting away and depositing of products (P) presented in a disordered manner on a receiving surface (101), the product positions of which on the receiving surface (101) are known, by means of one of several grippers (22) of a gripping head (20) of a robot (1), in which a) a recording group (AG) of products (P) to be recorded is automatically determined, the relative positions and in particular the rotational positions of the products (P) in the recording group (AG) to each other forming a recording pattern which is known or determined, b) the gripping head (20) is moved over the receiving group (AG) and lowered onto it, characterized by , that c) at the latest during the lowering, at least the relative position of the grippers (22) in the gripping head (20) to each other, i.e. the gripper pattern, is brought into a state corresponding to at least a part of the receiving pattern by controlled variation of the gripper distances between the grippers (22), d) at the end of the lowering, one product (P) is grasped by one gripper (22), in particular suction cups (22), preferably simultaneously, and the gripping head (20) is lifted up together with the products (P), moved away and the products (P) are deposited in real or virtual nests. [14] Method according to claim 13, characterized by , that e) at the latest during the lowering of the gripping head (20) onto the nest group (NG) - this is rotated about a vertical axis (10) until, viewed from above, the part of the gripper pattern that corresponds to the nest pattern coincides with the nest pattern, in particular the movement line (23) runs over the nests of the nest group (NG), in particular their centers, and / or - the individual grippers (22) are each rotated about their vertical axis (22') in such a way that the rotational positions of the products (P) hanging thereon relative to each other correspond to the rotational position of the nests in which they are to be deposited. [15] Method according to claim 13 or 14, characterized by , that f) at the latest during the lowering of the gripping head (20) onto the receiving group (AG), the latter is rotated about a vertical axis (10) until, viewed from above, the part of the gripper pattern which corresponds to the receiving pattern coincides with the receiving pattern.

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