DEVICE FOR GRIPPING FOOD OR PHARMACEUTICAL PRODUCTS

Description

[0001] The present invention relates to a device for gripping food or pharmaceutical products according to claim 1 and to a system for gripping and transporting food or pharmaceutical products.

[0002] Gripping devices are fundamental to the automated handling of individual parts or objects and are used in a wide variety of industries. Depending on the specific requirements, which are determined primarily by the weight and dimensions of the part or object to be gripped, various types of gripping devices are employed. These range from grippers with only a few (e.g., two) fingers, where the parts are gripped using a form-fit mechanism, to devices with a large number of movable fingers that operate using both form-fit and force-fit mechanisms. Other types also exist, including vacuum grippers, magnetic grippers, and adhesive grippers.

[0003] Even when there are significant differences between the weight and dimensions of the part or object to be gripped (such as the automatic gripping of a microprocessor versus a roof window for a passenger vehicle), the gripping processes performed in mechanical engineering, plant construction, and industrial manufacturing share the common characteristic that the parts and objects to be gripped are very precisely defined. This applies to the geometric dimensions of the parts or objects to be gripped, as well as their weight, material properties, surface finish, etc. Therefore, the design of industrial grippers for use in mechanical engineering typically consists of highly sophisticated mechanics that enable the gripping process to be carried out very precisely and with high repeatability.

[0004] The requirements for the food industry differ significantly from those in industrial machinery and equipment construction or manufacturing in this sector. A fundamental distinction in the food industry is whether the gripping device is intended to grip a pre-packaged food product or the food product itself. In the first case (gripping the pre-packaged food product), the contours and dimensions of the packaging are generally known, but the tolerances of the geometric dimensions of the packaging are typically much larger than the tolerances of industrially manufactured parts or objects in machinery and equipment construction or manufacturing in this sector. Furthermore, food packaging is, in most cases, sensitive to touch and must not be gripped or compressed with excessive force.In the second case (grasping the food itself), the dimensions and contours of the part or object to be grasped (namely the food) are only known in general terms and can deviate significantly from the norm, for example, when dealing with fruits and vegetables. Even with industrially manufactured products such as rolls, pieces of cheese, or pizzas, dimensional deviations of several millimeters must be expected. With other products, such as pieces of meat or fish fillets, even greater deviations in dimensions and contours from the norm must be anticipated. Furthermore, the properties of different foods, in terms of classic material properties such as density, hardness, ductility, brittleness, and surface texture, vary considerably.

[0005] A very precise gripping device, such as the one used above for industrial machine and apparatus construction and in industrial manufacturing in this area, which performs a positioning movement with a fixed predetermined force accurate to the hundredth of a millimeter, is therefore completely unsuitable for applications in the food sector, quite apart from the hygienic requirements of the food industry.

[0006] Therefore, in addition to gripping devices with moving fingers, vacuum grippers are also used in the food industry. However, since a complete seal between the suction head of the vacuum gripper and the product being gripped is often not possible in the food industry, the energy required to generate the necessary negative pressure is generally very high for vacuum grippers in this sector. Another problem with vacuum grippers in the food industry lies in the required hygiene and the fact that parts of the gripped product can enter the vacuum circuit. Especially with warm and therefore particularly sensitive food products, it is often impossible to avoid unwanted imprints on the product being gripped. Furthermore, the gripping process can only be controlled to a very limited extent, as the design and / or...The reduction of the negative pressure depends heavily on the degree of possible sealing between the suction head and the product to be gripped.

[0007] Magnetic gripping devices are limited to ferromagnetic parts or objects and are therefore generally unsuitable for use in the food industry. Similar requirements apply, in whole or in part, to pharmaceutical products.

[0008] Against this background, the invention is based on the objective of providing a device for gripping food and a system for gripping and transporting food that makes it possible to eliminate the aforementioned disadvantages.

[0009] The device designed according to the attached claim 1 for gripping food or pharmaceutical products comprises at least two stationary, firmly connected, and parallel straight guide rods made of stainless steel, a first gripper carriage with a first gripper arm attached to it, and a second gripper carriage with a second gripper arm attached to it.

[0010] The first and second gripper carriages each consist of a non-corrosive material, in particular non-corrosive plastic, and the first and second gripper arms each also consist of a non-corrosive material, in particular stainless steel. The first and second gripper carriages are each arranged on at least two guide rods, wherein at least the first gripper carriage is movable along the at least two guide rods. Furthermore, the device according to the invention comprises a first, in particular tubular, linear motor comprising a first stator which is enclosed in a liquid-tight manner by a casing made of a non-corrosive material, in particular stainless steel, and a first rotor arranged to be movable relative to the first stator, which has a liquid-tight rotor tube made of a non-corrosive material, in particular stainless steel, in which permanent magnets are arranged.

[0011] The first runner is rigidly connected to the first gripper carriage and the first stator is rigidly connected to at least one of the at least two guide rods, for moving the first gripper carriage along the at least two guide rods by moving the first runner relative to the first stator.

[0012] Linear motors are particularly suitable for moving gripper arms to pick up food products because they can apply the force required for gripping food in a controllable manner and are easy to operate. A linear motor suitable for use in the food industry is described, for example, in EP 3 790 172 A1. Using such linear motors to move the gripper arms is advantageous because they allow for easy cleaning. Furthermore, the force generated by the linear motor is provided directly by the rotor (i.e., virtually directly) without the need for deflection elements such as belts, gears, or spindles. Consequently, the losses typical of such deflection elements do not occur. Thus, the force provided by the rotor—neglecting minor friction losses—largely corresponds to the force generated by the linear motor.Patent documents US11542103B1 and US2013134726A1 disclose various examples of devices for gripping food or pharmaceutical products.

[0013] The use of non-corrosive materials allows the gripping device to be used in the food and pharmaceutical industries, although for the sake of simplicity, only the food industry will be discussed in the following. In particular, this enables cleaning with the cleaning agents commonly used in the food industry, which are often acidic. Stainless steel is especially advantageous for the guide rods, as it provides not only the necessary resistance to cleaning agents but also the required stability to support and guide the two gripper carriages. Similarly, the use of stainless steel is also advantageous for the stator and rotor of the linear motor, as it offers the necessary stability to securely connect the stator to at least one of the two guide rods and the rotor to the first gripper carriage.For gripper carriages, however, a non-corrosive plastic is particularly advantageous, firstly for reasons of weight (a lighter gripper carriage allows for rapid movement with minimal effort) and secondly for cost reasons. A suitable non-corrosive plastic is, for example, polyoxymethylene (POM).

[0014] The arrangement of the gripper carriages on at least two guide rods allows for a configuration that is stable against rotation of the gripper carriages about the longitudinal direction of the at least two guide rods and also stable against tilting of the gripper carriages in the longitudinal direction of the two guide rods. In one embodiment, the at least two guide rods are arranged one above the other, with the gripping arms oriented downwards and positioned below the at least two superimposed guide rods. This distributes the forces acting on the gripper carriages from the gripping arms due to leverage during the gripping process across the two superimposed guide rods. Particularly in embodiments where the gripper carriages are mounted on the at least two guide rods by means of a sliding bearing, this protects the sliding bearings.Accordingly, in an alternative arrangement of the gripper carriages on the guide rods, the linear ball bearings or rollers are protected by an alternative bearing arrangement of the gripper carriages, for example by means of linear ball bearings or rollers.

[0015] The fixed arrangement of the gripper arms on the gripper carriage offers the advantage that the leverage force acting on the two gripper arms during the gripping process is transferred to the guide rods, instead of acting directly on the linear motor's rotor, for example. This prevents the force from being transferred from the gripper arms to the linear motor's rotor, which could cause the rotor or its associated mounting to tilt.

[0016] A stationary arrangement of at least two guide rods is to be understood as stationary with respect to the gripping device itself, and not with respect to the product to be gripped. A parallel arrangement of the at least two guide rods allows easy movement of the first gripper carriage along the guide rods (or, if the second gripper carriage is also movable along the guide rods, also of the second gripper carriage).

[0017] The stator is rigidly connected to at least one of the at least two guide rods, but can also be rigidly connected to both (or all) guide rods. In this context, "rigidly connected" means that the stator is not movable relative to the guide rods, but is fundamentally adjustable with respect to its position along the longitudinal axis of the guide rods in which it is connected to at least one of them. This means that the stator can be positioned at various locations along the longitudinal axis of the guide rods and is rigidly connected to them at each position, thus preventing movement relative to them.In exemplary embodiments, the stator can, for example, be rigidly connected to the guide rods by means of a mounting block, wherein the mounting block serves to mount the gripping device to a transport device and also to rigidly connect at least two guide rods to each other. Accordingly, the position of the stator relative to the at least two guide rods can then be adjusted in the longitudinal direction of the guide rods by adjusting the position of the stator relative to the mounting block.

[0018] This makes the device suitable for gripping products of different sizes. By adjusting the position of the stator in the longitudinal direction of the two guide rods, the device according to the invention can be adapted to the size of the product to be gripped. The device according to the invention can thus be used to grip products of different sizes, such as a pizza or an olive, without having to replace the linear motors or use linear motors with a disproportionately large stroke. According to the invention, the second gripper carriage is also movable along the at least two guide rods (so that both the first and the second gripper carriage are movable along the guide rods), and the device further comprises a second, in particular tubular, linear motor. The second linear motor includes a second stator, which is enclosed in a liquid-tight manner by a casing made of a non-corrosive material, in particular stainless steel, and a second rotor arranged to be movable relative to the second stator, which has a liquid-tight rotor tube made of a non-corrosive material, in particular stainless steel, in which permanent magnets are arranged.

[0019] The second runner is rigidly connected to the second gripper carriage and the second stator is rigidly connected to at least one of the at least two guide rods, for moving the second gripper carriage along the at least two guide rods by moving the second runner relative to the second stator.

[0020] Because both the first and second gripper carriages are movable, and the second gripper carriage is driven by a separate linear motor, both gripper arms can be controlled and moved independently. The mobility of both gripper carriages, and therefore both gripper arms, allows products to be gripped without having to move the entire device to grip the product, as might be the case with a fixed arrangement of the second gripper carriage on the guide rods. This is particularly relevant when a gripper jaw attached to the gripper arm needs to be moved to a position below the product to be gripped.

[0021] Because the first and second gripper carriages are driven by separate linear motors, which can in turn be controlled independently, the first and second gripper arms can also be moved individually. This allows for asymmetrical movement of the two gripper arms, which can be advantageous, for example, when gripping products that are positioned close together or when one of the two gripper arms has limited movement due to spatial constraints. Furthermore, the gripped product can also be moved linearly within the range of motion of the gripper carriages.

[0022] Preferably, the first and second linear motors are arranged relative to each other such that the first and second rotors are parallel to each other but movable in opposite directions along the longitudinal axis of the guide rods. In particular, for space-saving reasons, the first and second stators are arranged, at least partially, in a region along the longitudinal axis of the guide rods between the first and second gripper carriages.

[0023] According to a further aspect of the device according to the invention, the at least two guide rods are hollow and have a circular cross-sectional profile. At least the first gripper carriage and, if applicable, also the second gripper carriage is arranged on the at least two guide rods by means of sliding bearings.

[0024] Hollow guide rods offer advantages in terms of weight and cost savings. A lighter device is easier to move and requires less force and energy. Guide rods with a circular cross-sectional profile can be manufactured cost-effectively and with high precision compared to guide rods with other cross-sectional profiles, and they also exhibit high stability.

[0025] Mounting the gripper carriages on the guide rods using plain bearings has the advantage that the plain bearings are easy to clean. Advantageously, each of the plain bearings includes at least one layer of an abrasion-resistant plastic.

[0026] According to a further aspect of the device according to the invention, a first gripper jaw is attached to the first gripper arm and a second gripper jaw is attached to the second gripper arm. The first gripper jaw and the second gripper jaw each consist of a non-corrosive material, in particular non-corrosive plastic.

[0027] The gripper jaws enable easy grasping of the product. The use of non-corrosive plastic as the material for the gripper jaws offers the advantage of relatively low mass, thus minimizing the overall moving mass of the gripper arm. Furthermore, plastic gripper jaws are inexpensive to manufacture, which is advantageous because they are typically interchangeable and can be adapted in size and shape depending on the application.

[0028] The gripper jaws can, for example, include jaw sections that can be moved under the product to be gripped. In this case, the product is not only held by frictional forces between the gripper jaws and the product, but is also lifted and supported at the bottom of the product.

[0029] According to another aspect of the device according to the invention, the first gripper arm and the second gripper arm are each designed as one or more rods.

[0030] Designing the gripper arm as (only) a single rod has the advantage of saving costs and weight. Designing the gripper arm as multiple rods has the advantage of being more resistant to twisting when forces act decentrally on the gripper jaw during the gripping process and generate a torque on the gripper arm. The gripper arm can, in particular, be designed as two rods.

[0031] According to another aspect of the device according to the invention, the first gripper arm or the second gripper arm, or both, comprise a force sensor for measuring a force acting on the respective gripper arm in the longitudinal direction of the at least two guide rods.

[0032] The force sensor(s) measure the force exerted on the product being gripped, and this force can be adjusted to a predefined value by controlling the linear motors accordingly. This is particularly advantageous in the food industry, as most food products are sensitive to mechanical forces. For force measurement, the gripper arms can be designed as shear beams or bending beams. Unlike force sensors located in the gripper jaws, arranging the force sensors in the gripper arms offers the advantage that the gripper jaws can be interchangeable, eliminating the need to replace the force sensor when changing the jaws. This allows for a simpler and more cost-effective gripper jaw design.To measure the force exerted on the product during the gripping process, it is generally sufficient for only one of the gripper arms to be equipped with a force sensor. However, arranging one force sensor in each gripper arm is advantageous because the force on the gripper arms can be measured even before the gripping process is complete, i.e., before the gripper arms are fully closed. This is particularly useful if initially only one gripper arm is in contact with the product. Depending on the measured force, the first or second linear motor can then be controlled accordingly during the gripping process.

[0033] According to a further aspect of the device according to the invention, the device further comprises at least one mounting block for mounting the device on a transport device. The at least two guide rods are also firmly connected to each other by the at least one mounting block.

[0034] Typically, the product is transported after being gripped. Using the gripping device alone, this is possible in the longitudinal direction of the guide rods (i.e., within the possible range of motion of the gripper carriage). However, the mounting block allows the gripping device to be additionally mounted to a transport device, thus enabling movement of the gripping device and, consequently, transport of the gripped products to a significantly greater extent and in other directions. The rigid connection of the guide rods via the mounting block ensures that the force of the transport device acts on all guide rods and not just a single one, thereby distributing the force across all of them. Furthermore, this largely eliminates the need for additional connecting elements to firmly join at least two guide rods.

[0035] According to a further aspect of the device according to the invention, the first stator of the first linear motor and the second stator of the second linear motor are each arranged longitudinally along the at least two guide rods and parallel to each other, and are rigidly connected to the at least two guide rods in such a way that the first stator and the second stator overlap at least partially in the longitudinal direction of the at least two guide rods. The at least one mounting block comprises only a single mounting block, and both the first stator and the second stator are rigidly connected to the at least two guide rods by means of this single mounting block.

[0036] The overlapping arrangement of the first and second stators along the guide rods, with both stators rigidly connected to the guide rods by a single mounting block, allows for a space-saving design of the gripping device. Rigid connection here also means that the two stators are not movable relative to the guide rods due to the mounting block, but are fundamentally adjustable with respect to their position along the length of the guide rods where they are connected (by the mounting block). Accordingly, the position in which the two stators are rigidly connected to the guide rods can be adjusted so that the positions of the gripper arms are adapted to the size or dimensions of the product to be gripped.

[0037] According to a further aspect of the device according to the invention, the first stator of the first linear motor and the second stator of the second linear motor are each arranged longitudinally along the at least two guide rods and parallel to each other, and are rigidly connected to the at least two guide rods such that the first stator and the second stator are spaced apart from each other longitudinally along the at least two guide rods. The at least one mounting block comprises a first mounting block and a second mounting block, which differs from the first mounting block. The first stator is rigidly connected to the at least two guide rods by means of the first mounting block, and the second stator is rigidly connected to the at least two guide rods by means of the second mounting block.

[0038] This arrangement of the stators proves advantageous for gripping products whose size precludes mounting the first and second linear motors on a single mounting block. Otherwise, the required stroke of the linear motors would be very large, necessitating correspondingly large (and therefore complex) linear motors. The two separate mounting blocks—the first, which connects the first stator (of the first linear motor) to the guide rods, and the second, which connects the second stator (of the second linear motor) to the guide rods—allow the use of smaller (and therefore less complex) linear motors with shorter strokes. Furthermore, the rigid connection of the two guide rods by both the first and second mounting blocks also contributes to high stability.

[0039] According to the invention, the first rotor of the first linear motor is movable from an arrangement retracted into the first stator to an arrangement extended out of the first stator and back into the retracted arrangement, and the second rotor of the second linear motor is movable from an arrangement retracted into the second stator to an arrangement extended out of the second stator and back into the retracted arrangement, such that when the first and second rotors are moved out of the first stator and out of the second stator respectively, the first gripper carriage and the second gripper carriage are moved away from each other.

[0040] In this arrangement, the two stators (the first and the second stator) of the two linear motors (of the first linear motor and the second linear motor) can be arranged at least partially in the longitudinal direction of the guide axes between the two gripper carriages, thus saving space.

[0041] According to another aspect of the device according to the invention, the first or the second linear motor, or both, are tubular linear motors.

[0042] A tubular linear motor has a circular cylindrical hollow profile in the cross-section of the stator and a corresponding circular cylindrical outer profile of the rotor. Tubular linear motors are simple and reliable to manufacture and exhibit high stability. They are standard in many linear motor applications. According to another aspect of the device according to the invention, the first gripper carriage or the second gripper carriage, or both, comprise a recess extending longitudinally along the at least two guide rods. The recess is arranged on the respective side of the first gripper carriage or the second gripper carriage facing the first stator of the first linear motor.

[0043] In the event of an overlap of the first or second gripper carriage with the first stator in the longitudinal direction of the at least two guide rods, the recess partially surrounds the first stator in order to prevent contact between the first or second gripper carriage and the first stator.

[0044] According to a further aspect of the device according to the invention, the first gripper carriage or the second gripper carriage, or both, comprise a further recess extending in the longitudinal direction of the at least two guide rods. The further recess is arranged on a respective further side of the first gripper carriage or the second gripper carriage that faces the second stator of the second linear motor.

[0045] In the event of an overlap of the first or second gripper carriage with the second stator in the longitudinal direction of the at least two guide rods, the further recess partially surrounds the second stator in order to prevent contact between the first or second gripper carriage and the second stator.

[0046] The recess and / or the additional recess enables a compact design of the gripping device. In particular, each recess allows for an arrangement in which the respective stator (i.e., the first stator or the second stator, or both) is positioned in a direction perpendicular to the longitudinal direction of the guide rods, overlapping them and, for example, partially projecting between at least two guide rods. Such an arrangement is also advantageous for the transmission of force from the runner to the gripper carriage, as it minimizes the lever arm for transmitting the force from the respective runner to the associated gripper carriage (i.e., the point of application of the respective runner on the respective gripper carriage is as central as possible).Accordingly, any torque acting on the associated gripper carriage due to the eccentric engagement of the runner is also minimized, which protects the sliding bearings of the respective gripper carriage and also reduces the risk of the respective gripper carriage tilting on the guide rods.

[0047] According to a further aspect of the device according to the invention, the first stator, or the second stator, or both, can each be positioned at different positions in the longitudinal direction of the at least two guide rods. In each of the different positions, the respective stator is rigidly connected to at least one of the at least two guide rods.

[0048] This has the advantage that the device can be adapted to grip products of different sizes and dimensions without having to replace the linear motors. In production lines where food products of varying sizes are manufactured or processed, only one gripping device needs to be installed, which can be easily adapted to products of different sizes and dimensions.

[0049] As already mentioned, the second gripper carriage can be arranged to be movable longitudinally along at least two guide rods. However, according to another aspect of the device according to the invention, the second gripper carriage is fixedly arranged on the at least two guide rods.

[0050] In embodiments where the second gripper carriage is fixed to the at least two guide rods, only one linear motor is required (namely, the first linear motor for moving the first gripper carriage). This saves costs and weight, allowing the gripping device to be moved faster and more energy-efficiently by a suitable transport device.

[0051] According to a further aspect of the device according to the invention, the first gripper arm or the second gripper arm, or both, are designed in two parts. A first part of the two-part gripper arm comprises the force sensor. A second part of the two-part gripper arm has an arm extension that is detachably connected to the first part.

[0052] This two-part design of the gripper arm has the advantage that the second part of the gripper arm, which ultimately determines the length of the gripper arm, can be designed simply and cost-effectively and can be replaced to form gripper arms of different lengths, while the first part with the force sensors does not need to be replaced.

[0053] According to another aspect of the device according to the invention, the device further comprises a third grab carriage with a third grab arm attached to it, and a fourth grab carriage with a fourth grab arm attached to it.

[0054] The third and fourth gripper carriages are made of a non-corrosive material, in particular non-corrosive plastic, and the third and fourth gripper arms are each also made of a non-corrosive material, in particular stainless steel. The third and fourth gripper carriages are each arranged on at least two guide rods, and at least the third gripper carriage is movable along the at least two guide rods. The first and second gripper carriages, as well as the third and fourth gripper carriages, are arranged in pairs on the at least two guide rods. Furthermore, the device comprises a third, in particular tubular, linear motor comprising a third stator which is enclosed in a liquid-tight manner by a casing made of a non-corrosive material, in particular stainless steel, and a third rotor arranged to be movable relative to the third stator, which has a liquid-tight rotor tube made of a non-corrosive material, in particular stainless steel, in which permanent magnets are arranged.

[0055] The third runner is rigidly connected to the third gripper carriage and the third stator is rigidly connected to at least one of the at least two guide rods, for moving the third gripper carriage along the at least two guide rods by moving the third runner relative to the third stator.

[0056] This has the advantage that two products can be gripped and transported simultaneously with the device.

[0057] According to a further aspect of the device according to the invention, the fourth gripper carriage is also movable along the at least two guide rods, and the device further comprises a fourth, in particular tubular, linear motor. The fourth linear motor includes a fourth stator, which is enclosed in a liquid-tight manner by a casing made of a non-corrosive material, in particular stainless steel, and a fourth rotor arranged to be movable relative to the fourth stator, which has a liquid-tight rotor tube made of a non-corrosive material, in particular stainless steel, in which permanent magnets are arranged.

[0058] The fourth runner is rigidly connected to the fourth gripper carriage and the fourth stator is rigidly connected to at least one of the at least two guide rods, for moving the fourth gripper carriage along the at least two guide rods by moving the fourth runner relative to the fourth stator.

[0059] Because both the third and fourth gripper carriages are movable and driven by separate third and fourth linear motors, respectively, the third and fourth gripper arms can also be moved independently. The mobility of both the third and fourth gripper carriages, and thus of the third and fourth gripper arms, allows objects to be grasped without having to move the entire device to grip the product, as might be the case with a stationary arrangement of the fourth gripper carriage and thus the fourth gripper arm. The explanations above regarding the movable second gripper carriage and thus the second gripper arm apply accordingly to the fourth gripper carriage and thus the fourth gripper arm.

[0060] The inventive system for gripping and transporting food or pharmaceutical products comprises a device for gripping food or pharmaceutical products, as described above, and a transport device. The device for gripping food or pharmaceutical products is mounted on the transport device by means of at least one mounting block.

[0061] Such a system offers the same advantages as the inventive device for gripping food or pharmaceutical products, which will not be repeated here. The transport device allows the product gripped by the gripping device to be transported to a desired location (within the possible range of motion of the transport device).

[0062] Further advantageous aspects and embodiments will become apparent from the following description of exemplary embodiments of the invention with the aid of the schematic drawings. These show: Fig. 1 a perspective view of a first embodiment of the inventive device for gripping foodstuffs; Fig. 2 a perspective view of a second embodiment of the inventive device with a first arrangement of the first and second gripper carriages; Fig. 3 a perspective view of the second embodiment of the inventive device with a second arrangement of the first and second gripper carriages; Fig. 4 a perspective view of the second embodiment of the inventive device with a third arrangement of the first and second gripper carriages; Fig. 5 a perspective view of a third embodiment of the inventive device; Fig. 6 a perspective view of a fourth embodiment of the inventive device as part of an inventive system for gripping and transporting foodstuffs; Fig.Fig. 7 a perspective view of a fifth embodiment of the device according to the invention; Fig. 8 a perspective view of a sixth embodiment of the device according to the invention; Fig. 9 a perspective view of a gripper carriage with gripper arm; Fig. 10 a front view and a side view of a rod of a gripper arm; Fig. 11 a perspective view of a gripper arm with two rods according to . Fig. 10 and a gripper jaw attached to it; Fig. 12 a perspective view of another gripper arm with only one rod according to Fig. 10 and a gripper jaw attached to it; Fig. 13 a front view and a side view of another rod of a gripper arm; Fig. 14 a perspective view of a gripper arm with two rods according to Fig. 13 and a gripper jaw attached to it; Fig. 15 a perspective view of a gripper arm with only one rod according to Fig. 13 and a gripper jaw attached to it; Fig. 16 a side view of a rod of a two-part gripper arm; Fig. 17 a perspective view of a two-part gripper arm with two rods according to Fig. 16 and a gripper jaw attached to it; and Fig. 18 a perspective view of a two-part gripper arm with only one rod according to Fig. 16 and a gripper jaw attached to it.

[0063] Fig. 1 Figure 1 shows a first embodiment of a device 1 according to the invention for gripping foodstuffs. The device 1 comprises two straight guide rods 20, 21 made of stainless steel, which are rigidly connected to each other and arranged parallel and one above the other. Both guide rods 20, 21 are hollow and have a circular cross-sectional profile. The two guide rods 20, 21 are rigidly connected to each other via a mounting block 3, wherein the first guide rod 20 is rigidly arranged in a first opening 31 in the mounting block 3 and the second guide rod 21 is rigidly arranged in a second opening 32 in the mounting block 3. The mounting block 3 also has mounting holes 30 for mounting the device on a transport device. In addition, the two guide rods 20, 21 are each connected to each other at their longitudinal ends by a clamp 23, 24 for additional stabilization of the guide rods 20, 21.

[0064] A first gripper carriage 5 and a second gripper carriage 4 are arranged on the guide rods 20, 21. Both gripper carriages (i.e., both the first gripper carriage 5 and the second gripper carriage 4) are made of polyoxymethylene (POM). The second gripper carriage 4 is fixedly connected to the guide rods 20, 21, with a first opening 41 receiving the first guide rod 20 and a second opening 42 receiving the second guide rod 21. The second gripper carriage 4 can, in principle, be positioned at various locations along the guide rods 20, 21, but is fixed (i.e., not movable) to both guide rods 20, 21 at each position. The first gripper carriage 5 is movable along the guide rods 20, 21 (see double arrow).For this purpose, the gripper carriage 5 is arranged on the two guide rods 20, 21 by means of sliding bearings, which are arranged in two circular openings 51, 52 of the first gripper carriage 5, which accommodate the two guide rods 20, 21.

[0065] The device 1 further comprises a first, e.g., tubular, linear motor 6, which has a first stator 62 and a first rotor 61 arranged to be movable relative to the first stator 62. The first stator 62 is enclosed in a liquid-tight stainless steel casing. The first rotor 61 has a liquid-tight stainless steel rotor tube in which permanent magnets (not shown) are arranged. The first rotor 61 is fixedly connected to the first gripper carriage 5, and the first stator 62 is fixedly connected to the mounting block 3 and, by means of the mounting block 3, fixedly connected to the guide rods 20, 21. By moving the first rotor 61 relative to the first stator 62, the first gripper carriage 5 can be moved along the two guide rods 20, 21. The first stator 62 can, in principle, be positioned at various positions along the guide rods 20, 21, but is fixed in the respective position (i.e.,(non-movable) connected by means of the mounting block 3 to the two guide rods 20, 21.

[0066] Furthermore, the first gripper carriage 5 includes a recess 50 on the side facing away from the first stator 62, which extends longitudinally along the at least two guide rods. A corresponding further recess is arranged on the opposite side of the first gripper carriage 5, facing the first stator 62 (in Fig. 1 (not visible). The second gripper carriage 4 also includes a recess 40 on the side facing away from the first stator 62, which extends longitudinally along the two guide rods 20, 21. On the side facing the first stator 62, the second gripper carriage also has a corresponding further recess 44.

[0067] A first gripper arm 8 is attached to the first gripper carriage 5, and a second gripper arm 7 is attached to the second gripper carriage 4. The first gripper arm 8 is designed as two rods 80, 81, which are attached to the first gripper carriage 5 by means of two mounting pins 82, and to which a first gripper jaw 84 is attached. Similarly, the second gripper arm 7 is also designed as two rods 70, 71, which are attached to the second gripper carriage 4 by means of two mounting pins 72, and to which a second gripper jaw 74 is attached.

[0068] In the Fig. 1 In the arrangement shown, the first, movable gripper carriage 5 is in the position of maximum deflection.

[0069] Fig. 2 Figure 1 shows a second embodiment of the inventive device for gripping foodstuffs, comprising a first arrangement of the first and second gripper carriages. The illustration in Figure 2 shows a second embodiment of the device for gripping foodstuffs according to the invention, comprising a first arrangement of the first and second gripper carriages. Fig. 2 The device 101 shown comprises two straight stainless steel guide rods 120, 121, rigidly connected to each other and arranged parallel and one above the other. Both guide rods 120, 121 are hollow and have a circular cross-sectional profile. The two guide rods 120, 121 are rigidly connected to each other via a mounting block 103, wherein the first guide rod 120 is rigidly arranged in a first opening 131 in the mounting block 103 and the second guide rod 121 is rigidly arranged in a second opening 132 in the mounting block 103. Additionally, the two guide rods 120, 121 are each connected to each other at their longitudinal ends by a clamp 123, 124 for further stabilization of the guide rods 120, 121.

[0070] A first gripper carriage 105 and a second gripper carriage 104, made of POM, are arranged on the guide rods 120, 121. Both the first gripper carriage 105 and the second gripper carriage 104 are movable along the guide rods 120, 121 (see double arrows). For this purpose, the gripper carriages 104, 105 are mounted on the two guide rods 120, 121 by means of sliding bearings, with the two circular openings 151, 152 (see Fig. 3 ) of the first grab carriage 105, in which the sliding bearings of the first grab carriage 105 are arranged, as well as the two circular openings 141, 142 of the second grab carriage 104, in which the sliding bearings of the second grab carriage 104 are arranged, which accommodate the two guide rods 120, 121.

[0071] The device 101 further comprises a first, e.g., tubular, linear motor 106, which has a first stator 162 and a first rotor 161 arranged to be movable relative to the first stator 162. The first stator 162 is enclosed in a liquid-tight stainless steel casing, and the first rotor 161 has a liquid-tight stainless steel rotor tube in which permanent magnets (not shown) are arranged. The device 101 also comprises a second, e.g., tubular, linear motor 109, which is identical in construction to the first linear motor 106 and has a second stator 192 and a second rotor 191 movable relative to the second stator 192.

[0072] The first rotor 161 of the first linear motor 106 is fixedly connected to the first gripper carriage 105, and the second rotor 191 of the second linear motor 109 is fixedly connected to the second gripper carriage 104. Both the first stator 162 of the first linear motor 106 and the second stator 192 of the second linear motor 109 are each fixedly connected to the guide rods 120, 121 by means of the mounting block 103. They are arranged longitudinally along the at least two guide rods 120, 121 and parallel to each other, with the first stator 162 and the second stator 192 overlapping longitudinally along the two guide rods 120, 121. Fig. 2 (even completely). By moving the first runner 161 relative to the first stator 162, the first gripper carriage 105 can be moved along the two guide rods 120, 121. Similarly, by moving the second runner 191 relative to the second stator 192, the second gripper carriage 104 can be moved along the two guide rods 120, 121.

[0073] Both the first stator 162 and the second stator 192 can, in principle, be positioned at different locations along the guide rods 120, 121. In each position, however, the first stator 162 and the second stator 192 are fixedly connected to the two guide rods 120, 121 by means of the mounting block 103.

[0074] Both the first gripper carriage 105 and the second gripper carriage 104 each include a recess extending longitudinally along the at least two guide rods 120, 121, located on the side of the first gripper carriage or the second gripper carriage facing the first stator 162 of the first linear motor 106. Correspondingly, the first gripper carriage 105 and the second gripper carriage 104 each include a further recess 150, 140 located on the respective side of the first gripper carriage 105 or the second gripper carriage 104 facing the second stator 192 of the second linear motor 109.

[0075] A first gripper arm 108 is attached (fixed) to the first gripper carriage 105, and a second gripper arm 107 is attached (fixed) to the second gripper carriage 104. The first gripper arm 108 is designed as two rods 180, 181, which are attached to the first gripper carriage 105 by means of two mounting pins 182, and to which a first gripper jaw 184 is attached. Similarly, the second gripper arm 107 is also designed as two rods 170, 171, which are attached to the second gripper carriage 104 by means of two mounting pins 172, and to which a second gripper jaw 174 is attached.

[0076] In the Fig. 2 In the arrangement shown, both the first gripper carriage 105 and the second gripper carriage 104 are each in a position of maximum deflection.

[0077] In Fig. 3 is that in Fig. 2 The illustrated embodiment of the device according to the invention is shown with a second arrangement of the first gripper carriage 105 and the second gripper carriage 104. In this arrangement, the first rotor 161 is located relative to the first stator 162 of the first linear motor 106, and the second rotor 191 is located relative to the second stator 192 of the second linear motor 109, each in a position partially retracted into the respective stator 162, 192. The first gripper carriage 105 and the second gripper carriage 104 are, in comparison to the one shown in Fig. 2 The arrangement shown is moved towards each other. Accordingly, the gripper arms 107, 108 attached to the respective gripper carriages 104, 105, and thus the gripper jaws 174, 184 attached to the gripper arms 107, 108, are also moved towards each other.

[0078] In Fig. 4 is that in the Figuren 2 und 3 The illustrated embodiment of the device according to the invention is shown with a third arrangement of the first gripper carriage 105 and the second gripper carriage 104. In this third arrangement, the two rotors 161, 191 are located in an arrangement that is completely retracted into the respective stator 162, 192. In this arrangement, the first gripper carriage 105 and the second gripper carriage 104 partially overlap longitudinally with the first stator 162 and the second stator 192, respectively. On a side facing the second stator 192, the further recess 150 of the second gripper carriage 105 partially surrounds the second stator 192, thereby preventing contact between the second gripper carriage 105 and the second stator 192.The recess on the side of the first gripper carriage 105 facing the first stator 162 at least partially surrounds the first stator 162, thus preventing contact between the first gripper carriage 105 and the first stator 162 on the same side. On the side facing the second stator 192, the further recess 140 of the second gripper carriage 104 partially surrounds the second stator 192, thus also preventing contact between the second gripper carriage 104 and the second stator 192. The recess arranged on the side of the second gripper carriage 104 facing the first stator 162 at least partially surrounds the first stator 162, thus preventing contact between the second gripper carriage 104 and the first stator 162 on the side facing the first stator 162.

[0079] In the Fig. 4 In the arrangement shown, the gripper carriages 104, 105 and thus also the gripper arms 107, 108 have the smallest distance between them. The two gripper jaws 174 have a minimum distance d1 between them in this arrangement.

[0080] In Fig. 5 A third embodiment of the inventive device 201 for gripping foodstuffs is shown. The device 201 comprises two straight guide rods 220, 221, rigidly connected to each other and arranged parallel and one above the other. These guide rods are identical in construction to the guide rods described in the two preceding embodiments and are rigidly connected to each other via a mounting block 203. The first guide rod 220 is rigidly arranged in a first opening in the mounting block 203, and the second guide rod 221 is rigidly arranged in a second opening in the mounting block 203. Additionally, the two guide rods 220, 221 are each connected to each other at their longitudinal ends by a clamp 223, 224.

[0081] A first gripper carriage 205 and a second gripper carriage 204, both made of POM, are arranged on the guide rods 220 and 221. Both the first gripper carriage 205 and the second gripper carriage 204 are movable along the guide rods 220 and 221 (see double arrows). The gripper carriages 204 and 205 are mounted on the two guide rods 220 and 21 by means of sliding bearings, as is also the case in the first two embodiments and as already described above.

[0082] The device 201 further comprises a first, e.g., tubular, linear motor 206, which has a first stator 262 and a first rotor 261 arranged to be movable relative to the first stator 262. The device 201 also comprises a second, e.g., tubular, linear motor 209, which has a second stator 292 and a second rotor 291 movable relative to the first stator 292. The two linear motors 206, 209 are identical in construction to the linear motors 6, 106, 109 described in the first two embodiments.

[0083] The first rotor of the first linear motor 206 is rigidly connected to the first gripper carriage 205, and the second rotor 291 of the second linear motor 209 is rigidly connected to the second gripper carriage 204. Both the first stator 262 of the first linear motor 206 and the second stator 292 of the second linear motor 209 are rigidly connected to the mounting block 203 and, by means of the mounting block 203, rigidly connected to the guide rods 220, 221. They are arranged longitudinally along the at least two guide rods 220, 221 and parallel to each other, with the first stator 262 and the second stator 292 overlapping (partially) along the longitudinal direction of the two guide rods 220, 221. By moving the first runner 261 relative to the first stator 262, the first gripper carriage 205 can be moved along the two guide rods 220, 221.Accordingly, by moving the second runner 291 relative to the second stator 292, the second gripper carriage 204 can be moved along the two guide rods 220, 221.

[0084] Both the first stator 262 and the second stator 292 can, in principle, be positioned at various positions along the longitudinal direction of the guide rods 220, 221. In each position, however, both the first stator 262 and the second stator 292 are firmly connected to the two guide rods 220, 221 by means of the mounting block 203.

[0085] Both the first gripper carriage 205 and the second gripper carriage 204 each include a recess extending longitudinally along the at least two guide rods 220, 221, and arranged on a side of the first gripper carriage 205 and the second gripper carriage 204, respectively, facing the first stator 262 of the first linear motor 206. Correspondingly, the first gripper carriage 205 and the second gripper carriage 204 each include a further recess 250 and 240, respectively, arranged on a side of the first gripper carriage 205 and the second gripper carriage 204, respectively, facing the second stator 292 of the second linear motor 209.

[0086] A first gripper arm 208 is attached (fixed) to the first gripper carriage 205 and a second gripper arm 207 is attached (fixed) to the second gripper carriage 204.

[0087] The first gripper arm 208 is designed as two rods 280, 281, which are attached to the first gripper carriage 205 by means of two mounting pins 282 and to which a first gripper jaw 284 is attached. Similarly, the second gripper arm 207 is also designed as two rods 270, 271, which are attached to the second gripper carriage 204 by means of two mounting pins 272 and to which a second gripper jaw 274 is attached.

[0088] At the in Fig. 5 In the arrangement shown, both the first gripper carriage 205 and the second gripper carriage 204 are each in a minimally deflected position. In contrast to the arrangement shown in the Fig. 4 In the second embodiment of the device according to the invention, the first stator 262 of the first linear motor 206 and the second stator 292 of the second linear motor 209 are arranged offset from each other in the longitudinal direction of the two guide rods 220, 221, so that they only partially overlap in the longitudinal direction. As a result, the gripper jaws 274, 284 have a minimum distance d2 from each other, which is less than the minimum distance d1 of the corresponding gripper jaws 174, 184 in the second embodiment of the device according to the invention.

[0089] In Fig. 6 Figure 3 shows a fourth embodiment of the inventive device 301 for gripping foodstuffs, which is attached to a transport device as part of a system for gripping and transporting foodstuffs (shown by dashed lines). The device shown in Figure 301 is a fourth embodiment of the device for gripping foodstuffs, which is attached to a transport device as part of a system for gripping and transporting foodstuffs (shown by dashed lines). Fig. 6 The fourth embodiment of the device 301 according to the invention, as illustrated, essentially corresponds to the one described in the Figuren 2 bis 4 The second embodiment of the device 101 according to the invention is shown, with the exception of a force sensor described below. The corresponding reference numerals are therefore increased by two hundred compared to those in the Figuren 2 bis 4 The second embodiment described (even though they are not described in detail below).

[0090] The two rods 370, 371 of the second gripper arm 307 each have a force sensor 375, 376 for measuring a force acting on the second gripper arm 307 in the longitudinal direction of the guide rods 320, 321. The arrangement shown here corresponds to a bending beam arrangement.

[0091] The device 301 is attached to the transport device, indicated by the dashed lines, by means of the mounting block 303. The mounting block 303 comprises several mounting holes 330 by means of which the mounting block 303 is attached to the transport device. The transport system allows the device 301 to be moved both laterally (indicated by the crossed double arrows) and vertically (also indicated by a corresponding double arrow).

[0092] In Fig. 7 Figure 401 shows a fifth embodiment of the device 401 according to the invention for gripping foodstuffs. The device 401 comprises two straight guide rods 420, 421 made of stainless steel, which are rigidly connected to each other and arranged parallel and one above the other. Both guide rods 420, 421 are hollow and have a circular cross-sectional profile. The two guide rods 420, 421 are rigidly connected to each other via a first mounting block 403 and a second mounting block 435, wherein the first guide rod 420 is rigidly arranged in a first opening 431 in the first mounting block 403 and the second guide rod 421 is rigidly arranged in a second opening 432 in the first mounting block 403. Furthermore, the first guide rod 420 is rigidly arranged in a first opening 438 in the second mounting block 435 and the second guide rod 421 is rigidly arranged in a second opening 439 in the second mounting block 435.Additionally, the two guide rods 420, 421 are each connected at their longitudinal ends by a clamp 423, 424. Both the first mounting block 403 and the second mounting block 435 are each provided with mounting holes 430, 436 for mounting the device to a transport device.

[0093] A first gripper carriage 405 and a second gripper carriage 404, both made of POM, are arranged on the guide rods 420 and 421. Both the first gripper carriage 405 and the second gripper carriage 404 are movable along the guide rods 420 and 421 (see double arrows). The gripper carriages 404 and 405 are mounted on the two guide rods 420 and 421 by means of sliding bearings, as in the embodiments described above.

[0094] Furthermore, the device 401 comprises a first, e.g., tubular, linear motor 406, which has a first stator 462 and a first rotor 461 arranged to be movable relative to the first stator 462. The device 401 also comprises a second, e.g., tubular, linear motor 409, which is identical in construction to the first linear motor 406 and has a second stator 492 and a second rotor 491 movable relative to the first stator 492. The two linear motors 406 and 409 are identical in construction to the linear motors described in the first four embodiments.

[0095] The first rotor 461 of the first linear motor 406 is rigidly connected to the first gripper carriage 405, and the second rotor 491 of the second linear motor 409 is rigidly connected to the second gripper carriage 404. The first stator 462 of the first linear motor 406 is rigidly connected to the first mounting block 403 and, by means of the first mounting block 403, rigidly connected to the guide rods 420, 421, and is arranged longitudinally along the at least two guide rods 420, 421. The second stator 492 of the second linear motor 409 is rigidly connected to the second mounting block 435 and, by means of the second mounting block 435, rigidly connected to the guide rods 420, 421, and is also arranged longitudinally along the at least two guide rods 420, 421 and parallel to the first stator 462 of the first linear motor 406.The first stator 462 and the second stator 492 are not arranged overlapping along the longitudinal direction of the two guide rods 420, 421, but are spaced apart from each other along the longitudinal direction of the two guide rods 402, 420. By moving the first runner 461 relative to the first stator 462, the first gripper carriage 405 can be moved along the two guide rods 420, 421. Similarly, by moving the second runner 491 relative to the second stator 492, the second gripper carriage 404 can be moved along the two guide rods 420, 421.

[0096] Both the first stator 462 and the second stator 492 can be positioned at various locations along the longitudinal direction of the guide rods 420, 421. In each position, the first stator 462 is fixedly connected to the two guide rods 420, 421 by means of the first mounting block 403, and the second stator 492 is also fixedly connected to the two guide rods 420, 421 in each position by means of the second mounting block 435.

[0097] Both the first gripper carriage 405 and the second gripper carriage 404 each include a recess extending longitudinally along the at least two guide rods 420, 421, located on the respective side of the first gripper carriage or the second gripper carriage facing the first stator 462 of the first linear motor 406. Correspondingly, the first gripper carriage 405 and the second gripper carriage 404 each include a further recess 450 or 440, respectively, located on the respective side of the first gripper carriage 405 or the second gripper carriage 404 and facing the second stator 492 of the second linear motor 409.

[0098] A first gripper arm 408 is attached to the first gripper carriage 405, and a second gripper arm 407 is attached to the second gripper carriage 404. The first gripper arm 408 is designed as two rods 480, 481, which are attached to the first gripper carriage 405 by means of two mounting pins 482, and to which a first gripper jaw 484 is attached. Similarly, the second gripper arm 407 is designed as two rods 470, 471, which are attached to the second gripper carriage 404 by means of two mounting pins 472, and to which a second gripper jaw 474 is attached.

[0099] The two rods 470, 471 of the second gripper arm 407 each have a force sensor 475, 476 for measuring a force acting on the second gripper arm 407 in the longitudinal direction of the guide rods 420, 421. The two rods 480, 481 of the first gripper arm 408 also each have a force sensor 485, 486 for measuring a force acting on the first gripper arm 408 in the longitudinal direction of the guide rods 420, 421. The arrangements of the force sensors 475, 476, 485, 486 shown here each correspond to a bending beam arrangement.

[0100] In the Fig. 7 In the illustrated embodiment, the distance between the two gripper jaws 474, 484 is significantly greater than in the two preceding embodiments. This enables the gripping of products with considerably larger dimensions than in the previously described embodiments.

[0101] Fig. 8 Figure 6 shows a sixth embodiment of the inventive device 501 for gripping foodstuffs. The device 501 comprises two straight guide rods 520, 521 made of stainless steel, rigidly connected to each other and arranged parallel and one above the other. Both guide rods 520, 521 are hollow and have a circular cross-sectional profile. The two guide rods 520, 521 are rigidly connected to each other via a first mounting block 503 and a second mounting block 5003, wherein the two guide rods 520, 521 are rigidly arranged in the first mounting block 503 and the second mounting block 5003 in the manner already described for the embodiments explained above. In addition, the two guide rods 520, 521 are each connected to each other at their longitudinal ends by a clamp 523, 524.

[0102] A first gripper carriage 505 and a second gripper carriage 504 are arranged on the guide rods 520, 521, and are identical in construction to the gripper carriages 405, 404 described in the preceding embodiments. Both the first gripper carriage 505 and the second gripper carriage 504 are movable along the guide rods 420, 421 (see double arrows). The gripper carriages 504, 505 are mounted on the two guide rods 520, 521 by means of sliding bearings, as in the embodiments described above, in which both gripper carriages are movable.

[0103] The device 501 further comprises a first, e.g., tubular, linear motor 506, which has a first stator 562 and a first rotor 561 (not shown) arranged to be movable relative to the first stator 562. The device 501 also comprises a second, e.g., tubular, linear motor 509, which is identical in construction to the first linear motor 506 and has a second stator 592 and a second rotor 591 movable relative to the first stator 592. The two linear motors 506 and 509 are identical in construction to the linear motors in the embodiments described above, in which both gripper carriages are movable.

[0104] The rotor 561 of the first linear motor 506 is rigidly connected to the first gripper carriage 505, and the second rotor 591 of the second linear motor 509 is rigidly connected to the second gripper carriage 504. Both the first stator 562 and the second stator 592 are rigidly connected to the first mounting block 503 and, by means of the first mounting block 503, rigidly connected to the guide rods 520, 521, and are arranged longitudinally along the at least two guide rods 520, 521 and parallel to each other. The first stator 562 and the second stator 592 overlap longitudinally along the two guide rods 520, 521. By moving the first rotor 561 relative to the first stator 562, the first gripper carriage 505 can be moved along the two guide rods 520, 521. Accordingly, by moving the second runner 591 relative to the second stator 592, the second gripper carriage 504 can be moved along the two guide rods 520, 521.

[0105] A first gripper arm 508 is attached to the first gripper carriage 505, and a second gripper arm 507 is attached to the second gripper carriage 504. The gripper arms 507 and 508 are identical in construction to the gripper arms 407 and 408 described in the preceding embodiment. A first gripper jaw 584 is attached to the first gripper arm 508, which is designed as two rods 580 and 581, and a second gripper jaw 574 is attached to the second gripper arm 507, which is also designed as two rods 570 and 571.

[0106] A third gripper carriage 5005 and a fourth gripper carriage 5004 are also arranged on the guide rods 520, 521. These are identical in construction to the first gripper carriage 505 and the second gripper carriage 504. Both the third gripper carriage 5005 and the fourth gripper carriage 5004 are movable along the guide rods 520, 521 (see double arrows). The gripper carriages 5004, 5005 are mounted on the two guide rods 520, 521 by means of sliding bearings, as in the embodiments described above in which both gripper carriages are movable.

[0107] The device 501 further comprises a third, e.g., tubular, linear motor 5006, which has a third stator 5062 and a third rotor 5061 (not shown) arranged to be movable relative to the third stator 5062. The device 501 also comprises a fourth, e.g., tubular, linear motor 5009, which has a fourth stator 5092 and a fourth rotor 5091 movable relative to the fourth stator 5092. The third linear motor 5006 and the fourth linear motor 5009 are identical in construction to the first linear motor 506 and the second linear motor 509, respectively.

[0108] The third rotor 5061 of the third linear motor 5006 is rigidly connected to the third gripper carriage 5005, and the fourth rotor 5091 of the fourth linear motor 5009 is rigidly connected to the fourth gripper carriage 5004. Both the third stator 5062 and the fourth stator 5092 are rigidly connected to the second mounting block 5003 and, by means of the second mounting block 5003, rigidly connected to the guide rods 520, 521. They are arranged longitudinally along the at least two guide rods 520, 521 and parallel to each other, with the third stator 5062 and the fourth stator 5092 overlapping longitudinally along the two guide rods 520, 521. By moving the third rotor 5061 relative to the third stator 5062, the third gripper carriage 5005 can be moved along the two guide rods 520, 521. Accordingly, by moving the fourth runner 5091 relative to the fourth stator 5092, the fourth gripper carriage 5004 can be moved along the two guide rods 520, 521.

[0109] A third gripper arm 5008 is attached to the third gripper carriage 5005, and a fourth gripper arm 5007 is attached to the fourth gripper carriage 5004. The gripper arms 5007 and 5008 are identical in construction to the gripper arms 407 and 408 described in the preceding embodiment. A third gripper jaw 5084 is attached to the third gripper arm 5008, and a fourth gripper jaw 5074 is attached to the fourth gripper arm 5007.

[0110] Fig. 9 Figure 1 shows an embodiment of a gripper carriage 604 with a gripper arm 607 attached to it, which is largely identical in construction (except for the force sensors) to the second gripper carriages (or correspondingly 'mirrored' to the first gripper carriages) of the embodiments shown in the preceding figures. The gripper carriage 604 has a first opening 641 and a second opening 642, each with a circular cross-sectional profile, which extend through the gripper carriage 604 in the longitudinal direction of the guide rods. The gripper carriage 604 comprises a gripper arm 607, which is designed as two rods 670, 671 that are (fixed) to the gripper carriage 604 via mounting pins 672, 673. A gripper jaw 674 is attached to the two rods 670, 671. In the embodiment shown here, the gripper jaw 674 is designed as a simple block.In other embodiments, the gripper jaw 674 can also be configured differently. A force sensor 675 or 676, not shown here, is arranged on each of the two rods 670 and 671, respectively. The gripper carriage 604 has a recess 640 that extends longitudinally along the at least two guide rods, as described above. The recess 640 is located on the side of the gripper carriage 604 that faces the second stator when the gripper carriage 604 is mounted on the guide rods. A corresponding further recess is located on the opposite side, which faces the first stator when the gripper carriage 604 is mounted on the guide rods. The recess 640 extends over the entire length of the gripper carriage 604, while the recess 644 is limited by a mounting plate 646 to which the runner of the first linear motor is attached.

[0111] Fig. 10 Figure 1 shows an embodiment of a rod 770 of a gripper arm in a front view and a side view. The rod 770 includes a mounting pin 778 for firmly connecting the rod 770 to the gripper carriage by means of the associated fastening pin. The rod 770, designed as a bending beam, has a section 777 of reduced thickness in which a first strain gauge 775a and, on an opposite side, a second strain gauge 775b are arranged, together forming the force sensor. The section of reduced thickness serves as a target bending point. Due to the different elongation of the two strain gauges when a force is applied, the bending of the rod 770, designed as a bending beam, can be determined using the two strain gauges 775a and 775b.

[0112] Fig. 11 Figure 1 shows an embodiment of a gripper arm 707 with two rods 770, 771, wherein each rod 770, 771 is designed according to the design shown in Figure 2. Fig. 10 The rod 770 shown corresponds to the force acting on the gripper jaw 774. The two rods 770 and 771 are rigidly connected to the gripper jaw 774. With the arrangement shown here, the force acting on the gripper jaw 774 in the longitudinal direction of the guide rods can be determined using the known dimensions of the rods 770 and 771, which are designed as bending beams. By designing the gripper arm 707 as two rods 770 and 771, it is possible to prevent the force measurement using the strain gauges 775a, 775b, 776a, and 776b from being distorted when gripping a product in such a way that the force does not act centrally on the gripper jaw 774. Furthermore, by adding the force measured by the strain gauges 775a, 776a and the respective corresponding strain gauges 775b, 776b arranged opposite each other (represented by short black arrows in the drawing), which is applied to the respective rod 770 or 776b, the following can be determined:771 acts to determine the total force acting on the gripper jaw 774 (represented by a long arrow in the drawing).

[0113] The signals measured by the strain gauges can then be passed on to a control unit, which evaluates these signals and can control the linear motors in a suitable manner.

[0114] Fig. 12 Figure 1 shows an embodiment of a gripper arm 807 with only one rod 870, which in its design is similar to the one in Figure 2. Fig. 10 The rod 770 shown corresponds to the force sensor, which comprises a force sensor formed by two strain gauges 875a, 875b and is rigidly connected to the gripper jaw 874. The embodiment shown here is particularly suitable for gripping operations in which the force acts centrally on the gripper jaw 874 (indicated by the long arrow).

[0115] Fig. 13 Figure 1 shows an embodiment of a rod 970 of a gripper arm in a front view and a side view. The rod 970, designed here as a shear beam, has a recess 977 in which a first strain gauge 975a and, on the opposite side of the recess 977, a second strain gauge 975b are located, together forming the force sensor. The recess 977 serves as the measuring point. Based on the shear stress measured by the two strain gauges 975a and 975b, the force acting on the rod 970 can be determined.

[0116] Fig. 14 Figure 1 shows an embodiment of a gripper arm with two rods 970, 971, wherein each of the rods 970, 971 is designed according to the configuration shown in Figure 2. Fig. 13 The rod shown corresponds to 970. The two rods 970 and 971 are firmly connected to the gripper jaw 974.

[0117] Fig. 15 shows an embodiment of a gripper arm 1007 with only one rod 1070, which in its design is similar to the one in Fig. 13 The rod shown corresponds to 970 and includes a force sensor formed by two strain gauges 1075a, 1075b and is firmly connected to a gripper jaw 1074.

[0118] Fig. 16 Figure 1 shows an embodiment of a rod 1170 of a two-part gripper arm 1107. The rod 1170 comprises a first part designed as a connecting part 1179 with an integrated force sensor 1175. The rod 1170 further comprises a second part designed as an interchangeable extension 1172. The interchangeable extension 1172 is detachably connected to the connecting part 1179.

[0119] Fig. 17 Figure 1 shows an embodiment of a gripper arm 1107 with two rods 1170, 1171, wherein each of the rods 1170, 1171 is designed according to the design shown in Figure 1. Fig. 16 The rod 1170 shown corresponds to the two detachable extensions 1172 and 1173 of the rods 1170 and 1171, respectively, are each firmly but detachably connected to the gripper jaw 1174. The gripper arm 1107, with the two rods 1170 and 1171 and the gripper jaw 1174 attached to them, can be firmly connected to the corresponding gripper carriage via the two connecting parts 1178 and 1179, which include the respective force sensors 1175 and 1176.

[0120] Fig. 18 shows an embodiment of a gripper arm 1207 with only one rod 1270, which in its design is similar to the one in Fig. 12 The rod shown corresponds to 870 and is firmly connected to the gripper jaw 1274.

[0121] The inventive device for gripping and the inventive system for gripping and transporting foodstuffs have been explained above with reference to exemplary embodiments. However, the invention is not limited to these exemplary embodiments, but is also intended to include exemplary embodiments that make use of the technical teaching of the invention. The scope of protection is therefore defined by the following patent claims.

Claims

1. Device (1; 101; 201; 301; 401; 501) for gripping food products or pharmaceutical products, comprising: - at least two static, straight guide rods (20, 21; 120, 121; 220, 221; 320, 321; 420, 421; 520, 521) made of stainless steel, which guide rods are fixedly connected to one another and arranged in parallel, - a first gripper carriage (5; 105; 205; 305; 405; 505) having a first gripper arm (8; 108; 208; 308; 408; 508) attached thereto, - a second gripper carriage (4; 104; 204; 304; 404; 504) having a second gripper arm (7; 107; 207; 307; 407; 507) attached thereto, wherein the first and second gripper carriages each consist of a non-corrosive material, in particular non-corrosive plastics, and the first and second gripper arms likewise each consist of a non-corrosive material, in particular stainless steel, wherein the first and second gripper carriages are each arranged on the at least two guide rods, and wherein at least the first gripper carriage is movable along the at least two guide rods, and - a first, in particular tubular, linear motor (6; 106; 206; 306; 406; 506), comprising - a first stator (62; 162; 262; 362; 462; 562), which is fluid-tightly enclosed by a casing made of a non-corrosive material, in particular stainless steel, and - a first slider (61; 161; 261; 361; 461; 561) arranged so as to be movable relative to the first stator, which first slider has a fluid-tight slider tube made of a non-corrosive material, in particular stainless steel, in which permanent magnets are arranged, wherein the first slider is fixedly connected to the first gripper carriage and the first stator is fixedly connected to at least one of the at least two guide rods, for movement of the first gripper carriage along the at least two guide rods by movement of the first slider relative to the first stator, wherein the second gripper carriage (104; 204; 304; 404; 504) is also movable along the at least two guide rods (120, 121; 220, 221; 320, 321; 420, 421; 520, 521), and wherein the device further comprises a second, in particular tubular, linear motor (109; 209; 309; 409; 509), the second linear motor comprising - a second stator (192; 292; 392; 492; 592), which is fluid-tightly enclosed by a casing made of a non-corrosive material, in particular stainless steel, and - a second slider (191; 291; 391; 491; 591) arranged so as to be movable relative to the second stator, which second slider has a fluid-tight slider tube made of a non-corrosive material, in particular stainless steel, in which permanent magnets are arranged, wherein the second slider is fixedly connected to the second gripper carriage and the second stator is fixedly connected to at least one of the at least two guide rods, for movement of the second gripper carriage along the at least two guide rods by movement of the second slider relative to the second stator, and wherein the first slider (161; 261; 361; 461; 561) of the first linear motor (106; 206; 306; 406; 506) is movable out of an arrangement in which it is retracted into the first stator (162; 262; 362; 462; 562) into an arrangement in which it has moved out of the first stator and back into the retracted arrangement again, and wherein the second slider (191; 291; 391; 491; 591) of the second linear motor (109; 209; 309; 409; 509) is movable out of an arrangement in which it is retracted into the second stator (192; 292; 392; 492; 592) into an arrangement in which it has moved out of the second stator and back into the retracted arrangement again, in such a way that during the movement of the first and second sliders out of the first stator and out of the second stator, respectively, the first gripper carriage (105; 205; 305; 405; 505) and the second gripper carriage (104; 204; 304; 404; 504) are moved away from one another.

2. Device according to claim 1, wherein the at least two guide rods (20, 21; 120, 121; 220, 221; 320, 321; 420, 421; 520, 521) are hollow and have a circular cross-sectional profile, and wherein at least the first gripper carriage (5; 105; 205; 305; 405; 505) and optionally also the second gripper carriage (4; 104; 204; 304; 404; 504) is arranged on the at least two guide rods by means of plain bearings.

3. Device according to any one of the preceding claims, wherein the first gripper arm (8; 108; 208; 308; 408; 508) and the second gripper arm (7; 107; 207; 307; 407; 507) are each configured as one or more rods (70, 71, 80, 81; 170, 171, 180, 181; 270, 271, 280, 281; 370, 371, 380, 381; 470, 471, 480, 481; 570, 571, 580, 581; 670, 671; 770, 771; 870; 970, 971; 1070; 1170, 1171; 1270).

4. Device according to any one of the preceding claims, wherein either the first gripper arm (408; 508) or the second gripper arm (407; 507), or both, comprise a force sensor (485, 486, 475, 476; 585, 586, 575, 576) for measuring a force acting on the respective gripper arm in the longitudinal direction of the at least two guide rods (420, 421; 520, 521).

5. Device according to any one of the preceding claims, wherein the device further comprises at least one mounting block (3; 103; 203; 303; 403, 435; 503; 5003) for mounting the device on a transport device, wherein the at least two guide rods (20, 21; 120, 121; 220, 221; 320, 321; 420, 421; 520, 521) are also fixedly connected to one another by the at least one mounting block.

6. Device according to claim 1 and claim 5, wherein the first stator (162; 262; 362) of the first linear motor (106; 206; 306) and the second stator (192; 292; 392) of the second linear motor (109; 209; 309) are each arranged in the longitudinal direction of the at least two guide rods (120, 121; 220, 221; 320, 321) and in parallel with one another and are fixedly connected to the at least two guide rods in such a way that the first stator and the second stator at least partly overlap in the longitudinal direction of the at least two guide rods, and wherein the at least one mounting block (103; 203; 303) has only a single mounting block and both the first stator and the second stator are fixedly connected to the at least two guide rods by means of the single mounting block.

7. Device according to claim 1 and claim 5, wherein the first stator (462) of the first linear motor (406) and the second stator (492) of the second linear motor (409) are each arranged in the longitudinal direction of the at least two guide rods (420, 421) and in parallel with one another and are fixedly connected to the at least two guide rods in such a way that the first stator and the second stator are spaced apart from one another in the longitudinal direction of the at least two guide rods (420, 421), wherein the at least one mounting block has a first mounting block (403) and a second mounting block (435) which is different from the first mounting block (430), and wherein the first stator (462) is fixedly connected to the at least two guide rods (420, 421) by means of the first mounting block (403) and the second stator (492) is fixedly connected to the at least two guide rods (420, 421) by means of the second mounting block (435).

8. Device according to any one of the preceding claims, wherein the first gripper carriage (5; 105; 205; 305; 405; 505) or the second gripper carriage (4; 104; 204; 304; 404; 504), or both, comprise a recess which extends in the longitudinal direction of the at least two guide rods, and wherein the recess is arranged on the first gripper carriage (5; 105; 205; 305; 405; 505) or on the second gripper carriage (4; 104; 204; 304; 404; 504) on a respective side that faces towards the first stator (62; 162; 262; 362; 462; 562) of the first linear motor (6; 106; 206; 306; 406; 506), wherein in the case where the first gripper carriage or the second gripper carriage overlaps the first stator in the longitudinal direction of the at least two guide rods, the recess partly surrounds the first stator in order to prevent the first gripper carriage or the second gripper carriage from making contact with the first stator.

9. Device according to any one of the preceding claims, wherein the first gripper carriage (105; 205; 305; 405; 505) or the second gripper carriage (104; 204; 304; 404; 504), or both, comprise a further recess (140, 150; 240, 250; 340, 350; 440, 450; 540, 550) which extends in the longitudinal direction of the at least two guide rods, and wherein the further recess (140, 150; 240, 250; 340, 350; 440, 450; 540, 550) is arranged on the first gripper carriage or on the second gripper carriage on a respective further side that faces towards the second stator of the second linear motor, wherein in the case where the first gripper carriage or the second gripper carriage overlaps the second stator in the longitudinal direction of the at least two guide rods, the further recess partly surrounds the second stator in order to prevent the first gripper carriage or the second gripper carriage from making contact with the second stator.

10. Device according to any one of the preceding claims, wherein the first stator (162; 262; 362; 462; 562), or the second stator (192; 292; 392; 492; 592), or both, are each positionable at various positions in the longitudinal direction of the at least two guide rods (120, 121; 220, 221; 320, 321; 420, 421; 520, 521) and wherein the respective stator is fixedly connected to at least one of the at least two guide rods at one of the various positions .

11. Device according to claim 4, wherein the first gripper arm or the second gripper arm (1107; 1207), or both, are of two-part construction, wherein a first part (1178, 1179) of the two-part gripper arm comprises the force sensor (1175, 1176), and wherein a second part of the two-part gripper arm has an arm extension (1170, 1171) which is detachably connected to the first part.

12. Device according to any one of the preceding claims, further comprising - a third gripper carriage (5005) having a third gripper arm (5008) attached thereto, - a fourth gripper carriage (5004) having a fourth gripper arm (5007) attached thereto. wherein the third and fourth gripper carriages consist of a non-corrosive material, in particular non-corrosive plastics, and the third and fourth gripper arms likewise each consist of a non-corrosive material, in particular stainless steel, wherein the third and fourth gripper carriages are each arranged on the at least two guide rods (520, 521), and wherein at least the third gripper carriage is movable along the at least two guide rods, and wherein the first gripper carriage (505) and the second gripper carriage (504) as well as the third gripper carriage (5005) and the fourth gripper carriage (5004) are arranged in associated pairs on the at least two guide rods, and - a third, in particular tubular, linear motor (5006), comprising - a third stator (5062), which is fluid-tightly enclosed by a casing made of a non-corrosive material, in particular stainless steel, and - a third slider arranged so as to be movable relative to the third stator, which third slider has a fluid-tight slider tube made of a non-corrosive material, in particular stainless steel, in which permanent magnets are arranged, wherein the third slider is fixedly connected to the third gripper carriage and the third stator is fixedly connected to at least one of the at least two guide rods, for movement of the third gripper carriage along the at least two guide rods by movement of the third slider relative to the third stator.

13. Device according to claim 12, wherein the fourth gripper carriage (5004) is also movable along the at least two guide rods (520, 521), and wherein the device further comprises a fourth, in particular tubular, linear motor (5009), the fourth linear motor comprising - a fourth stator (5092), which is fluid-tightly enclosed by a casing made of a non-corrosive material, in particular stainless steel, and - a fourth slider arranged so as to be movable relative to the fourth stator, which fourth slider has a fluid-tight slider tube made of a non-corrosive material, in particular stainless steel, in which permanent magnets are arranged, wherein the fourth slider is fixedly connected to the fourth gripper carriage and the fourth stator is fixedly connected to at least one of the at least two guide rods, for movement of the fourth gripper carriage along the at least two guide rods by movement of the fourth slider relative to the fourth stator.