EP3656729B1 - Gripping device and method for gripping a transport pallet - Google Patents

Description

The present application relates to a gripping device according to claim 1. The present application also relates to a method for gripping a transport pallet according to claim 12.

Devices by means of which transport pallets can be gripped and in this way can be pulled close to a loading edge of a transport vehicle are already known in the prior art. Purely as an example, reference is made to the so-called "pallet train" from the provider Bauer Südlohn ^® . The device shown there comprises a loading floor with a raised edge at the end. The loading floor can be driven on a subsurface, in particular a loading area of a truck, by means of two guide wheels. The pallet train can be guided by means of a push rod so that it can be brought into positive engagement with a transport pallet. Said intervention is effected by pivoting the loading floor around the axis of rotation of the wheels of the pallet train, the end-side upstand being raised and thereby brought into engagement with a crossbar of the respective pallet. As soon as the pallet train is then pulled back, ie is moved in a direction away from the transport pallet, the respective transport pallet is “pulled along” with the pallet train due to the positive engagement. In order to apply the necessary forces, the pallet hoist has a pull chain that can be connected to a forklift truck, for example. The pallet train, including the transport pallet coupled to it, can then be pulled in the direction of the loading sill by reversing the forklift, so that it can then be gripped in the usual way using the forks of the forklift.

The known device is disadvantageous insofar as the connection of the known pallet train with the respective transport pallet depends solely on the end-side upstand of the loading floor of the pallet train. In practice, this regularly means that when the respective transport pallet is pulled, the form fit that has been created "breaks off" and has to be re-established. Due to the considerable forces that can act when a transport pallet is pulled, this tearing off is also associated with a potential hazard.

Furthermore, from the U.S. 4,421,353A a gripping device for gripping a pallet is known. This has a tong-like shape, with two tong arms being pivotable relative to each other between an open position and a closed position. The gripping device is adapted to positively engage a crossbar of a pallet so that the pallet can be pulled using the gripping device.

The known gripping device is disadvantageous in that it has to be manually attached to the pallet for use. This means that a person using the gripping device has to approach the pallet and apply the gripping device to the crossbar. This makes it particularly necessary for the person to climb onto a loading area of a respective transport vehicle in order to reach the pallet and use the gripping device. Use without direct access to the pallet is not possible.

Another known gripping device that discloses the features of the preamble of claim 1 results from the US Patent Application 2007/0014654 A1 . This is a device for attachment to a carrying machine, such as a forklift. The gripping device comprises two gripping arms which correspond to one another and which can grip a pallet foot laterally, forming a frictional connection.

task

The present application is based on the object of providing a gripping device whose application is improved over the prior art.

solution

The underlying object is achieved according to the invention by means of the gripping device with the features of claim 1. Advantageous configurations result from subclaims 2 to 11.

The gripping device according to the invention comprises a base body and an actuating element that can be moved relative thereto. The base body interacts with at least two gripping arms, each of which has a coupling section and a hook section. The gripping arms are each coupled to the base body by means of the coupling sections, forming a pivot axis, with the gripping arms each being pivotable about their pivot axis relative to the base body. The pivot axes of the gripping arms can in particular be spaced apart from one another. Furthermore, it is conceivable that ends of the gripping arms facing away from the base body are at a greater distance from one another when they are in their open position than when the gripping arms are in their closed position. In this way, when the gripping arms are in their open position, the gripping device can be placed around a respective pallet foot before the gripping arms "snap shut" by moving them into their closed position and grip the pallet foot in a form-fitting manner. It is advantageous if the gripper arms are not in direct contact when they are in their closed position, in particular if their hook sections do not come into contact with one another. The coupling sections of the gripper arms are preferably oriented parallel to one another when they are in their closed position. Preferably, the gripper arms are straight.

The hook sections of the gripping arms are used to produce the positive engagement described between the gripping device and the respective pallet foot. For this purpose, the hook sections preferably form protruding areas which—in relation to the gripping arms—extend toward one another. By means of the above areas, it is achieved that gripper arms which, at least when they are in their closed position, are arranged at a distance from one another at least on the hook sections which corresponds to a width of a pallet foot of a transport pallet to be gripped, for example 14.5 cm for a typical Euro pallet, falls below The hook sections form contact surfaces which, when the gripper arms are in their closed position, can engage with a rear surface of the respective pallet foot to be gripped and prevent the pallet foot from accidentally escaping from a space located between the gripper arms. Consequently, the desired form fit between the gripping device and the pallet foot is effectively produced by means of the hook sections.

The actuating element of the gripping device can be moved translationally along an axis of action relative to the base body between a near position and a far position. In particular, it is conceivable that the actuating element can be guided along an inherently straight guide component, which is connected in a force-transmitting manner to the base body and along which the actuating element can slide, for example. The guide component can be formed, for example, by a guide rod or a push rod. The actuating element interacts with the gripping arms in a force-transmitting manner by means of at least one transmission means, so that by transferring the actuating element between its near position and its far position, a force can be exerted on the gripping arms, which causes a pivoting movement of the gripping arms about their respective pivot axis relative to the base body . The at least one translation means therefore serves to convert the translational movement of the To translate actuating element relative to the base body in a pivoting movement of the gripping arms relative to the base body. The transmission means is preferably fixed to the actuating element.

The gripping arms can be transferred from their open position to their closed position by actuating the actuating element. This actuation of the actuating element can also be carried out remotely, with the actuating element being able to be transferred from its near position to its remote position by "pulling back", whereby as a result of the kinematic coupling of the actuating element and gripper arms, the latter are transferred from their open position to their closed position. The retraction can easily take place by means of a traction device at least indirectly connected to the actuating element, which is advantageously formed by the same traction device by means of which the gripping device and finally the transport pallet connected thereto in a form-fitting manner are pulled in the direction of the loading edge. It is thus possible, for example, to connect the actuating element to a traction device by means of an adapter element, which can be formed, for example, from a traction chain or a traction belt. Conversely to the transfer of the gripping arms from their open position to their closed position by retracting the actuating element (i.e. by transferring the latter to its remote position), the gripping arms can be converted from their closed position to their open position by transferring the actuating element to its near position.

According to the invention, the hook sections of the gripping arms each have a flank that has at least one inclined area. The flanks are arranged on mutually facing sides of the hook portions of the gripping arms. In the oblique areas, the flanks of the hook sections are configured obliquely in such a way that they—viewed in the direction of the base body—are configured to run towards one another. This means that end points of the flanks of the gripping arms facing away from the base body are at a greater distance from one another than near-side points of the flanks facing the base body. The distance between the end points of the flanks is preferably greater than the width of the respective pallet foot of the transport pallet to be gripped, while the distance between the near-side points of the flanks is smaller than the width of the pallet foot. In particular, the distance between the end locations can be greater than 14.5 cm, preferably greater than 15.0 cm, more preferably greater than 15.5 cm, while the distance between the near-side locations is less than 14.5 cm, preferably less than 12.0 cm, more preferably less than 9.0 cm.

The gripping device according to the invention has many advantages. In particular, the gripping arms can be transferred “automatically” from their closed position to their open position as it were, as soon as they engage with a pallet foot to be gripped. This is based on the consideration that the inclined areas of the flanks, in the course of the movement of the gripping device onto the pallet foot, come into contact with the lateral edges of the panel foot facing the gripping device, with the gripping arms being "pushed apart" as a result of the inclined design of the inclined areas and therefore starting from their Closed position are moved towards their open position. Due to the coupling of the gripping arms to the actuating element by means of the at least one transmission means, the actuating element is forced from its remote position towards its near position. The gripper arms will automatically open as a result of contact with the foot of the plate as far as necessary to allow the gripper arms to be placed around the foot of the plate. As soon as the gripping arms grip the pallet foot in such a way that the hook sections—seen from the base body—have reached beyond a rear surface of the pallet foot, the gripping arms can be transferred to their closed position so that they engage with the pallet foot in a form-fitting manner.

The design of the sloping flanks on the hook sections has the particular advantage that the gripping device is designed to be self-opening, whereupon the gripping arms do not have to be manually moved into their open position before the gripping device is used. Furthermore, due to the oblique design of the oblique areas, the alignment of the gripping device relative to the pallet foot also takes place automatically. Manual operation of the gripping device directly on the transport pallet to be gripped is therefore completely unnecessary. Alternatively, the gripping device can be moved remotely towards the transport pallet and engaged with the pallet foot, whereupon the gripping arms are transferred to their open position as a result of engagement with the pallet foot in the manner described. The gripping device according to the invention therefore allows a transport pallet to be gripped without the need to enter the loading area of the respective transport vehicle. In particular, the gripping device can be guided with the gripping arms in their open position and the gripping arms can be moved into their closed position by actuating the actuating element remotely. The customary in the prior art getting on and off the loading area can therefore be completely eliminated. Furthermore, it is particularly easy to use the gripping device according to the invention to grip a respective transport pallet securely, ie in a way that the force-transmitting connection between the gripping device and transport pallet not inadvertently dissolved. The latter is regularly to be lamented when using the pallet train mentioned at the outset, since the raised end of the pallet train can lose its engagement with the transport pallet simply by rotating it slightly about the axes of rotation of the guide wheels.

To grip a transport pallet, it is conceivable to guide the gripping device, for example by means of an elongated push rod, from a position outside the loading area in the direction of the respective transport pallet. The gripping device is "targeted" in such a way that the gripping arms come into engagement with a pallet foot, as a result of which the gripping arms are forced into their open position due to the inclined flanks of their hook sections. As soon as the hook sections of the gripper arms reach the rear surface of the pallet foot, by exerting a tensile force on the actuating element, the latter is then transferred from its near position, which corresponds to the open position of the gripper arms, to its remote position, i.e. moved away from the base body relative to it. As a result, the transmission means achieve the effect that the gripping arms are pivoted about their respective pivot axis relative to the base body in the direction of their closed position, in which at least the hook sections of the gripping arms engage in a form-fitting manner with the rear surface of the pallet foot facing away from the base body. The further pulling on the actuating element can then be used to pull the gripping device, including the transport pallet now positively connected thereto, in the direction of the loading edge.

Advantageously, the actuating element and the base body can be brought into force-transmitting engagement with one another by means of a blocking element, the blocking element blocking movement of the actuating element away from the base body beyond a certain distance, which preferably corresponds to the remote position of the actuating element. In this way it is achieved that the actuating element can be moved away from the base body at most until it reaches its remote position, whereupon due to the blocking element a further exertion of a tensile force on the actuating element can be transmitted directly to the base body and thus the rest of the gripping device. This design has the particular advantage that the gripping device can be pulled in the direction of the loading edge by pulling on the actuating element, which prevents the actuating element from moving unintentionally in the course of this movement, starting from its remote position towards its near position and consequently in unintentional pivoting of the gripper arms in the direction of their open position brings about. In the worst case, the latter would lead to the positive connection between the gripping device and the transport pallet being broken. In contrast, the embodiment mentioned is designed to be self-locking, since pulling on the actuating element prevents unintentional movement of the same in the direction of its near position.

Further developing the gripping device according to the invention, the pivot axes of the gripping arms are spaced apart from one another, with the base body preferably interacting with at least two transmission means, each of which is associated with one of the gripping arms. This configuration allows the gripping arms to be arranged at a distance from one another, which makes it easier to design the gripping arms to be self-opening in the manner described.

In a further advantageous embodiment of the gripping device according to the invention, this includes a cable which is in operative connection with the base body and the actuating element, so that the actuating element can be moved from its remote position to its near position by actuating the cable. In particular, the cable pull can include a pull cable that is connected to the base body. In this way, the base body can be “pulled” towards the actuating element by shortening the traction cable, which can be done for example by means of an actuating device, so that the distance between the base body and the actuating element is reduced. In this way, the actuating element is indirectly transferred from its remote position to its near position. The cable pull helps to release the gripping device from a pallet foot again from a distance.

Further developing the gripping device according to the invention, the gripping arms each have at least one guide groove, which each interact with a translation means. The latter can in particular be fixed to the actuating element and is formed, for example, by a bolt. It is equally conceivable here that the guide grooves of both gripping arms interact with the same transmission means or dedicated transmission means in each case. The guide grooves are advantageously aligned obliquely with respect to the gripping device such that projections of longitudinal axes of the guide grooves and a projection of the axis of action of the actuating element, along which it can be moved translationally relative to the base body, enclose an angle in a common plane. The projection plane described is oriented perpendicular to the pivot axes of the gripping arms. The angle that the longitudinal axes of the guide grooves and the axis of action in the presence of Includes gripping arms in their closed position is preferably between 1° and 45°, preferably between 5° and 35°, more preferably between 10° and 25°. A corresponding embodiment of a gripping device according to the invention is shown below using the exemplary embodiment. When the gripping arms are in their open position, the angle is preferably between 1° and 50°, preferably between 10° and 40°, more preferably between 20° and 30°.

If the gripping arms each include a guide groove, it can also be advantageous if the at least one translation means has at least one guide carriage that can interact with the guide groove of a respective gripping arm. Advantageously, the actuating element interacts with two transmission means, one of which is associated with one of the gripping arms. In this case, each of the actuating elements comprises a respective guide carriage cooperating with the associated guide groove. The guide carriage is designed in such a way that it can be guided along the guide groove, so that the transfer of the actuating element between its near position and its remote position is accompanied by a movement of the guide carriage along the guide groove. Due to the above-described oblique orientation of the longitudinal axis of a respective guide groove in relation to the axis of action of the actuating element, the movement of the guide carriage along the guide groove leads to a force directed laterally in relation to the axis of action, which ultimately causes the respective gripper arm to pivot about its pivot axis in relation to the base body . In other words, a translation of the translational movement of the actuating element relative to the base body into a rotary movement of the gripping arms relative to the base body is achieved in this way. The gripping arms and the actuating element are kinematically coupled in such a way that a reverse, equally forced movement of the gripping arms between their open position and their closed position causes a corresponding movement of the actuating element between its near position and its far position.

In a further advantageous embodiment of the gripping device according to the invention, the same comprises an elongate push rod which is coupled or can be coupled to the base body in a force-transmitting manner. It is particularly conceivable that the push rod can be connected to the base body by means of a non-destructively releasable connection without tools, so that a respective push rod can be exchanged for another push rod. This can be of interest, for example, for the gripping device for differently designed loading areas to be rebuilt, which have different lengths measured from the loading sill. Advantageously, a length of the push rod significantly exceeds a length of a respective gripping arm measured in the direction of the axis of action, preferably by at least twice, more preferably by at least three times. In this way, the gripping device can be used to grip a respective transport pallet from a corresponding distance. The push rod is designed to be pressure-resistant, so that the gripping device can be guided by means of the push rod along the loading area by exerting a compressive force. The push rod is advantageously arranged relative to the base body in such a way that, in addition to its guiding function for the gripping device as a whole, it also fulfills a guiding function for the actuating element. In particular, the actuating element can have a recess, preferably in the middle, by means of which the actuating element can be moved translationally along a longitudinal axis of the connecting rod. In such a configuration, the axis of action of the actuating element and the longitudinal axis of the push rod coincide. A corresponding configuration can also be found in the exemplary embodiment below.

The gripping device according to the invention is also advantageously designed in such a way that it is mirror-symmetrical with respect to a mirror plane running parallel to the pivot axes of the gripping arms and containing the axis of action of the actuating element. This mirror symmetry relates in particular to the gripping arms, of which at least one is located on each side of the mirror plane in this constellation.

Furthermore, it can be advantageous if the gripping device comprises at least one restoring element, which is arranged between the base body and the actuating element. The restoring element can in particular be formed by a compression spring. The restoring element is advantageously prestressed with a compressive force, so that the actuation element is pressed in a direction away from the base body by the action of the restoring element in the absence of other external forces. This configuration has the advantage that the actuating element, at least to a certain extent, even in the absence of a deliberately applied tensile force, by means of which the actuating element is to be transferred from its near position to its far position, precisely this movement "independently", i.e. solely by effect of the restoring element. In this way, the gripping device is designed to be self-closing, with the gripping arms being held in their closed position, which corresponds to the remote position of the actuating element, by means of the action of the restoring element.

By using the flanks of the hooked sections of the gripper arms, which are slanted according to the invention, it is possible by means of such a gripping device to move the latter automatically into its open position as a result of engaging with a respective pallet foot, with the actuating element being kinematically coupled to the gripper arms against the force of the restoring element in is moved in the direction of its near position. As soon as the hook sections reach the rear surface of the pallet foot, the gripping arms are automatically transferred into their closed position due to the compressive force stored in the restoring element, so that the gripping device automatically "snaps" or "snaps" onto the pallet foot. The separate actuation of the actuating element by a person operating the gripping device is then no longer necessary.

The combined design of the gripping device according to the invention with the sloping flanks and the reset element therefore offers a self-centering, self-opening and self-closing gripping device. The opening of the gripping device, i.e. the transfer of the gripping arms from their closed position to their open position in order to release the gripping device from the respective transport pallet, can finally be done manually without further ado, because the transport pallet together with the gripping device is pulled up to the loading edge, whereupon manual actuation of the actuating element is possible without having to climb onto the loading area of the transport vehicle. This can then be moved against the force of the compression spring in the direction of its near position until the gripping arms are at least opened far enough for the hook sections to lose their form-fitting engagement with the rear surface of the pallet foot. The gripping device can then be detached from the pallet foot.

In a further advantageous embodiment, the gripping device according to the invention comprises at least one support element which is arranged on an underside of the rest of the gripping device. The support element is used to store at least the gripper arms at a certain distance from the loading area of the respective transport vehicle, so that the gripping arms avoid a collision with a longitudinal board of the transport pallet resting on the loading area during the course of connection to a respective transport pallet. This configuration of the gripping device is particularly adapted to the commercially available Euro pallets, which are provided with described longitudinal boards both on their upper side and on their lower side. These have a certain thickness, which means that the pallet feet arranged between the transverse slats are not arranged directly on the loading area, but at a certain distance from the loading area, which corresponds to the thickness of the longitudinal boards. To reliably engage the gripper arms To bring the respective pallet foot, it is therefore advantageous to also guide the gripper arms at just such a distance above the loading area. The support element described above fulfills precisely that function, with a height of the support element preferably corresponding to a thickness of a respective longitudinal board of a respective transport pallet. In the course of guiding the gripping device along the loading area by means of a push rod, the gripping device slides over the loading area. The use of the support element offers the further advantage that a friction surface between the gripping device and the loading area is reduced compared to a full-surface contact. Accordingly, it is possible with comparatively little effort to push the gripping device along the loading area.

Furthermore, it can be of particular advantage if the gripping device comprises four gripping arms, with two gripping arms each being combined to form a pair of gripping arms. The gripping arms belonging to a pair of gripping arms can be connected to one another in a force-transmitting manner, in particular by means of at least one connecting means, preferably by means of a plurality of connecting means. The gripper arms can each be formed in particular from a piece of sheet metal, which are arranged at a certain distance from one another by means of the connecting means. A separate form of the gripping device designed in this way meets even the highest demands on mechanical strength without using a solid structure that would unnecessarily increase the mass of the gripping device.

1. a) Eine Greifvorrichtung, die mindestens zwei an einem Grundkörper angeordnete Greifarme umfasst, wird in Richtung auf die Transportpalette zu geführt, wobei die Greifarme jeweils mindestens einen Hakenabschnitt aufweisen, wobei einander zugewandte Flanken der Hakenabschnitte jeweils zumindest einen Schrägbereich aufweisen, innerhalb dessen die Flanken schräg aufeinander zu laufend ausgebildet sind, wobei ein Abstand zwischen dem Grundkörper abgewandten endseitigen Stellen der Flanken der Greifarme größer ist als ein Abstand zwischen nahseitigen Stellen der Flanken, die an einem dem Grundkörper zugewandten Ende der Flanken angeordnet sind.
2. b) Die Greifarme werden derart in Kontakt mit einem Palettenfuß der Transportpalette gebracht, dass Schrägbereiche einander zugewandter Flanken von Hakenabschnitten der Greifarme in Kontakt mit dem Palettenfuß treten, wodurch die Greifarme voneinander weg gedrückt und die Greifarme auf diese Weise in eine Offenstellung überführt werden.
3. c) Die Greifvorrichtung wird solange weiter in Richtung auf die Transportpalette zu geführt, bis zumindest Hakenabschnitte der Greifarme über eine dem Grundkörper gegenüberliegende Rückfläche des Palettenfußes hinausgeführt sind.
4. d) Ein Betätigungselement, das mittels mindestens eines Übersetzungsmittels mit den Greifarmen zusammenwirkt, wird relativ zu dem Grundkörper entlang einer Wirkungsachse in eine Richtung von dem Grundkörper sowie von der Transportpalette weg bewegt, wobei diese Bewegung mittels des Übersetzungsmittels in eine Schwenkbewegung der Greifarme übersetzt und letztere hierdurch in ihre Schließstellung überführt werden, sodass die Hakenabschnitte der Greifarme mit der Rückfläche des Palettenfußes eingreifen.

The underlying object is also achieved from a procedural point of view by means of a method having the features of claim 12 . Advantageous configurations result from the dependent claims 13 to 15. The method according to the invention comprises the following method steps:

1. a) A gripping device, which comprises at least two gripping arms arranged on a base body, is guided in the direction of the transport pallet, with the gripping arms each having at least one hook section, with flanks of the hook sections facing each other having at least one inclined region, within which the flanks are inclined are designed to run towards one another, with a distance between end-side points of the flanks of the gripping arms facing away from the base body being greater than a distance between near-side points of the flanks which are arranged at an end of the flanks facing the base body.
2. b) The gripping arms are brought into contact with a pallet foot of the transport pallet in such a way that inclined areas of flanks facing one another of hook portions of the gripping arms come into contact with the pallet base, as a result of which the gripping arms are pushed away from one another and the gripping arms are thus transferred into an open position.
3. c) The gripping device is guided further in the direction of the transport pallet until at least hook sections of the gripping arms are guided beyond a rear surface of the pallet foot opposite the base body.
4. d) An actuating element, which interacts with the gripper arms by means of at least one transmission means, is moved relative to the base body along an axis of action in a direction away from the base body and from the transport pallet, this movement being translated into a pivoting movement of the gripper arms and the latter by means of the transmission means are thereby transferred into their closed position, so that the hook sections of the gripping arms engage with the rear surface of the pallet foot.

The method according to the invention can be carried out particularly easily using the gripping device according to the invention. The advantages that can be achieved by means of the method have already been explained above in connection with the gripping device. In particular, it is possible to operate the gripping device remotely due to its self-opening properties. Furthermore, the gripping arms of the gripping device can be transferred from their open position to their closed position by actuating the actuating element, with this actuation of the actuating element also being able to be carried out particularly well from a distance. Alternatively or additionally, the actuation can take place by means of a restoring element, which is explained above. In any case, the method is designed in such a way that it is possible to grip a transport pallet without climbing onto the loading area of a respective transport vehicle. As a result, it is also possible to pull the respective transport pallet in the direction of the loading edge of the transport vehicle without having to step onto the loading area.

The method is also particularly advantageous because the gripping arms are automatically pivoted about a pivot axis relative to the base body as a result of contact with the pallet foot during the connection of the gripping device to the respective transport pallet and are thus transferred from their closed position towards their open position. This automatic opening of the gripping arms can be achieved in particular by means of the above-described sloping areas, which are provided with lateral side edges of the pallet foot and in this way exert a lateral opening force on the gripper arms.

In a further refinement of the method according to the invention, at least one restoring element, preferably in the form of a compression spring, is tensioned during the transfer of the gripper arms in the direction of their open position, so that the gripper arms are guided beyond the rear surface of the pallet foot by the action of a force stored in the restoring element at the moment their hook sections are guided Restoring force are automatically transferred towards their closed position. The resulting advantages have already been explained above in connection with the gripping device. In particular, a self-closing mechanism can be achieved in this way, which makes the use of the gripping device particularly simple and safe.

Finally, it is particularly advantageous if the gripping arms are moved towards the base body from their closed position in the direction of their open position by moving the actuating element. This translation of the movement of the actuating element into the corresponding movement of the gripping arms is achieved by means of at least one transmission means which kinematically couples the actuating element to the gripping arms.

exemplary embodiments

Fig. 1:

Eine isometrische Ansicht einer erfindungsgemäßen Greifvorrichtung, die sich in formschlüssigem Eingriff mit einem Palettenfuß befindet,

Fig. 2:

Eine Draufsicht der Greifvorrichtung gemäß Figur 1, wobei sich die Greifarme in ihrer Schließstellung befinden,

Fig. 3:

Ein vertikaler Querschnitt durch die Greifvorrichtung gemäß Figur 1,

Fig. 4:

Ein horizontaler Querschnitt durch die Greifvorrichtung gemäß Figur 1,

Fig. 5:

Die Greifvorrichtung gemäß Figur 1, wobei sich die Greifarme in ihrer Offenstellung befinden, und

Fig. 6:

Eine isometrische Ansicht der Greifvorrichtung gemäß Figur 1, wobei sich die Greifarme in ihrer Offenstellung befinden.

The gripping device according to the invention and the method according to the invention are explained in more detail below using an exemplary embodiment which is illustrated in the figures. It shows:

Figure 1:

An isometric view of a gripping device according to the invention, which is in positive engagement with a pallet foot,

Figure 2:

A top view of the gripping device according to FIG figure 1 , with the gripping arms in their closed position,

Figure 3:

A vertical cross section through the gripping device according to FIG figure 1 ,

Figure 4:

A horizontal cross-section through the gripping device according to FIG figure 1 ,

Figure 5:

The gripping device according to figure 1 , wherein the gripper arms are in their open position, and

Figure 6:

An isometric view of the gripping device according to FIG figure 1 , with the gripper arms in their open position.

The embodiment in the Figures 1 to 6 is shown comprises a gripping device 1 according to the invention, which is equipped here with a total of four gripping arms 4 and a base body 3 and an actuating element 5 . In each case two of the gripping arms 4 are combined to form a pair of gripping arms by means of coupling means 31, which are formed here by threaded bolts. The gripping arms 4 belonging to a pair of gripping arms are each of identical design and are arranged at a distance from one another by means of the coupling means 31 . The coupling means 31 serve to connect the gripping arms 4 to one another in a force-transmitting manner so that they act as a unit. The pairs of gripping arms formed in this way are arranged opposite one another, so that together they are suitable for enclosing a pallet foot 2 in a form-fitting manner. This is particularly based on figure 1 recognizable.

The gripping arms 4 each comprise a coupling section 7 and a hook section 8. The gripping arms 4 are connected to the base body 3 by means of the coupling section 7 , each forming a pivot axis 10, 11 . The pivot axes 10, 11 are arranged at a distance from one another and are oriented parallel to one another. The gripping arms 4 are in particular relative to the base body 3 about the respective associated pivot axis 10, 11 pivotable, so that the gripping arms 4 between one in the figures 1 , 2 and 4 shown closed position and one in the figures 5 and 6 shown open position can be transferred. Furthermore, the gripping arms 4 each have a guide groove 14 in their coupling section 7 , the function of which will be explained separately below.

The hook sections 8 are arranged on an end of the gripping arms 4 facing away from the base body 3 . They are used to positively engage with a rear surface 28 of the pallet foot 2 , so that the pallet foot 2 and consequently a transport pallet, not shown in the figures, can be gripped in a form-fitting manner. For this purpose, the hook sections 8 each have a protruding area, with the hook sections 8 of one pair of gripping arms extending by means of their respective protruding areas towards the hook sections 8 of the other pair of gripping arms and vice versa. In this way, it is achieved that points 33 of the gripping arms 4 that face each other and are close to each other when they are in the closed position are arranged at a distance 34 from one another, which is smaller than a width 35 of the pallet foot 2. The distance 34 is 8 in the example shown .0 cm. In this way it is achieved that contact surfaces 42 of the hook sections 8 can come into contact with the rear surface 28 of the pallet foot 2 , as a result of which the pallet foot 2 is gripped in a form-fitting manner.

The hook sections 8 are each also equipped with inclined areas 12 which are formed along mutually facing flanks 9 of the hook sections 8 . In these oblique areas 12 , the flanks 9 are configured obliquely and extend towards one another in such a way that the gripper arms 4 as a whole form a funnel-shaped inlet area, so to speak. This is designed in such a way that a distance 36 between corresponding end points 40 of the gripping arms 4, which are located at an end of the gripping arms 4 facing away from the base body 3 , is greater than the width 35 of the pallet foot 2. In particular, the distance is 36 in the figure shown Example 15.5 cm, while the width 35 of pallet foot 2 is 14.5 cm. This has the technical effect that the gripping device 1 can easily be brought into engagement with a respective pallet foot 2 when its gripping arms 4 are in the closed position, since the gripping arms 4 can, so to speak, "by means of their inclined regions 12 in cooperation with lateral edges 37 of the pallet foot 2 are pressed open" or "spread open", that is, starting from their closed position, they are transferred in the direction of their open position. This is particularly evident from the figures 5 and 6 .

Optionally, the gripping device 1 also includes an in figure 4 cable pull 43 shown. This in turn comprises a pull cable 44 which is arranged between an end-side anchor point 45 on the base body 3 and an end of a guide rod 18 remote from the actuating element 5 , by means of which the gripping device 1 can be guided. In the example shown, the traction cable 44 is guided through the actuating element 5 to the base body 3 by means of a bore. By actuating an actuating device 46 of the cable pull 43 , it is now possible to shorten the pull cable 44 , so that a tensile force is exerted on the base body 3 , which acts in the direction of the actuating element 5 . The force-transmitting connection between the traction cable 44 and the base body 3 is established by means of the anchor point 45 . The movement of the base body 3 towards the actuating element 5 causes an opening movement of the gripping arms 4, as explained below. In this way it is possible to force the gripper arms 4 to open by means of the cable pull 43 .

The actuating element 5, which is formed here by a plate, is connected to the gripper arms 4 in a force-transmitting manner by means of a transmission means 6 in each case. In the example shown, the transmission means 6, which are directly connected to the actuating element 5 , each comprise a pin which extends upwards or downwards, starting from an upper side 38 or an underside 39 of the actuating element 5 . As a result, the translation means 6 are suitable to positively engage in the respective guide grooves 14 of the gripper arms 4 , wherein the

Translation means 6 each advantageously have a guide carriage 17 which is designed to fit the respective guide groove 14 and can be guided within the same along a longitudinal axis 15 of the respective guide groove 14 . This is evident in particular from figure 4 . The guide grooves 14 or their longitudinal axis 15 are formed obliquely with respect to an axis of action 13 along which the actuating element 5 can be moved relative to the base body 3 . This oblique arrangement is characterized in that projections of the longitudinal axes 15 of the guide grooves 14 and the axis of action 13 in a common plane, which is the plane of the drawing figure 4 corresponds to an angle 16, 41 together. When the gripper arms 4 are in their closed position (see figure 4 ) the angle 16 is illustrated for the sake of simplicity using an axis 29 parallel to the axis of action 13 . Here it is approx. 10°. In the course of transferring the gripper arms into their open position, they are pivoted about their respective pivot axis 10, 11 relative to the base body 3 , which also changes the orientation of the longitudinal axes 15 of the guide grooves 14 . When the gripper arms are in their open position (see figures 5 and 6 ) the angle 41 is approx. 25° here. A pivoting angle by which the gripper arms 4 rotate between their closed and open positions relative to the base body 3 is therefore approximately 15° in the example shown.

The execution of the guide grooves 14 in an oblique orientation relative to the axis of action 13 means that a translational movement of the actuating element 5 between one in the figures 1 , 2 and 4 shown remote position, in which the actuating element 5 is arranged at a maximum distance from the base body 3 , and in the figures 5 and 6 shown close-up position, in which the actuating element 5 is arranged at a minimal distance from the base body 3 , causes a force acting laterally on the gripper arms 4 . The reason for this is that the transmission means 6 are arranged in a stationary manner on the actuating element 5 and therefore cannot follow the oblique course of the guide grooves 14 in the course of the movement of the actuating element. Therefore, conversely, the gripping arms 4 are forced to move in the lateral direction with respect to the axis of action 13 due to the kinematic connection between the actuating element 5 and the gripping arms 4 . Due to the mounting of the gripper arms 4 each forming a pivot axis 10, 11 on the base body 3 , the former have a degree of freedom required for such a movement, which allows them to pivot relative to the base body 3 . The result of this pivoting is the transfer of the gripping arms 4 between their open position and their closed position. In this way, the transmission means 6 with their guide carriages 17 together with the guide grooves 14 act as a kind of effect Transmission, by means of which the translatory movement of the actuating element 5 relative to the base body 3 can be translated into a rotary movement of the gripper arms 4 relative to the base body 3 .

In the example shown, the actuating element 5 is mounted by means of a guide rod 18 which is connected to the base body 3 in a force-transmitting manner. For this purpose, the actuating element 5 has a central recess in which the guide rod 18 is accommodated. At least in a region that extends between the near position and the far position, the actuating element 5 and the base body 3 are connected to one another only indirectly via the gripper arms 4 in a manner that transmits force. At one end of the guide rod 18 facing away from the base body 3 , the guide rod 18 includes a block element 30, which is designed here in the form of a knob. A diameter of this knob exceeds a diameter of the recess of the actuating element 5 so that movement of the latter in a direction away from the base body 3 beyond the remote position of the actuating element 5 is blocked by the blocking element 30 .

In the example shown, the actuating element 5 interacts with a tubular pulling element 19 which, starting from the plate-shaped actuating element 5 , extends in a direction away from the base body 3 . The pulling element 19 and the guide rod 18 are arranged coaxially to one another, so that a longitudinal axis 20 of the guide rod 18 and the axis of action 13 of the actuating element 5 coincide. At its end facing away from the actuating element 5 , the pulling element 15 interacts with an adapter element 32 , which is suitable for being equipped with a pulling means, not shown in the figures, in particular a pulling strap. In this way, the actuating element 5 can be pulled in the direction of a loading edge of a transport vehicle together with the rest of the gripping device 1 and together with a transport pallet coupled thereto. The guide rod 18 can be designed in different lengths, whereby the gripping device 1 can be operated by means of the guide rod 18 from outside the loading area, so that according to the invention it is not necessary to climb onto the loading area in order to couple the gripping device 1 to the respective transport pallet to be pulled.

In the example shown, two compression springs 21 are arranged between the base body 3 and the actuating element 5 , which are prestressed with a compressive force. The compression springs 21 ensure that, in the absence of other external forces, the actuating element 5 is always held in its remote position or, starting from its near position, is pressed into its remote position. This ensures that the gripping device 1 is designed to be self-closing. This works as follows: in the train a coupling of the gripping device 1 according to the invention with a pallet base 2 , the gripping arms 4 are first brought to the pallet base 2 . By further guiding the gripping device 1 towards the pallet foot 2 , the inclined areas 12 of the hook sections 8 are brought into engagement with the lateral edges 37 of the pallet foot 2 . Due to the oblique design of the oblique areas 12 , a lateral force is exerted on the gripper arms 4 , which causes the gripper arms 4 to be transferred from their closed position towards their open position. Due to the kinematic coupling of the gripping arms 4 to the actuating element 5 by means of the transmission means 6 , this movement of the gripping arms 4 is accompanied by a translatory movement of the actuating element 5 along its axis of action 13 towards the base body 3 . Although the compression springs 21 acting between the base body 3 and the actuating element 5 counteract this movement of the actuating element 5 , they are not sufficiently rigid to block the movement. The gripping arms 4 are now guided with their hook sections 8 along side surfaces 26, 27 of the pallet foot 2 until the gripping arms 4 are guided with their hook sections 8 over the rear surface 28 of the pallet foot 2 . Then the gripping arms 4 can be transferred from their open position to their closed position. This transfer takes place automatically due to the compressive force stored in the compression springs 21 , ie without the application of an additional external force, in that the compression springs 21 push the actuating element 5 away from the base body 3 along its axis of action 13 . As a result of the kinematic coupling of the actuating element 5 to the gripper arms 4 , the latter are transferred into their closed position.

A subsequent opening of the gripping arms 4 for the purpose of removing the gripping device 1 from the respective pallet foot 2 can then only be done manually by moving the actuating element 5 against the compressive forces of the compression springs 21 from its remote position to its near position, whereby the gripping arms 4 are in their open position be transferred. This decoupling of the gripping device 1 from the pallet foot 2 can be done particularly conveniently from outside the loading area of the respective transport vehicle as soon as the respective transport pallet has been pulled up to the loading edge of the transport vehicle.

On an underside 23 , the gripping device 1 shown has two support elements 22 , which are made of wood here. The support elements 22 are each assigned to one of the pairs of gripping arms and form a lower support surface for the gripping device 1 on the respective loading area. The support elements 22 cause the rest of the gripping device 1 to be arranged at a distance 24 from the loading area, which is not shown in the figures. which corresponds to a height 25 of the support elements 22 . The latter is selected in such a way that when the gripping device 1 is guided along the loading area, the pairs of gripping arms can engage directly with a respective pallet foot 2 and, in particular, a collision of the pairs of gripping arms with a crossbar running below the pallet foot 2 is prevented. The latter typically form a lower end in the case of the Euro pallets that are customary in practice.

Reference List

1

gripping device

2

pallet foot

3

body

4

gripper arm

5

actuator

6

means of translation

7

coupling section

8th

hook section

9

flank

10

pivot axis

11

pivot axis

12

inclined area

13

axis of action

14

guide groove

15

longitudinal axis

16

angle

17

guide carriage

18

push rod

19

tension element

20

longitudinal axis

21

compression spring

22

support element

23

bottom

24

Distance

25

Height

26

side face

27

side face

28

back surface

29

axis

30

blocking element

31

coupling agent

32

adapter element

33

Job

34

Distance

35

Broad

36

Distance

37

edge

38

top

39

bottom

40

Job

41

angle

42

contact surface

43

cable pull

44

pull rope

45

anchor point

46

operating unit

Claims (15)

1. Gripping device (1) for positively gripping a pallet base (2) of a transporting pallet, comprising

   - a basic body (3),

   - at least two gripper arms (4) arranged on the basic body (3),

   - an operating element (5) as well as

   - at least one translational means (6),

   wherein the gripper arms (4) each comprise at least one coupling section (7) and at least one hook section (8), wherein by way of their coupling sections (7), in each case forming a swivel axis (10, 11), the gripper arms (4) are coupled to the basic body (3), so that the gripper arms (4) can each be swivelled relative to the basic body (3) between an open setting and a closed setting,

   wherein the operating element (5) can be moved in a translational manner along an axis of action (13) relative to the basic body (3) between a near setting and a remote setting,

   wherein by means of the at least one transmission means (6), the operating element (5) interacts with the gripper arms (4) in such a way that a movement of the operating element (5) between its near setting and its remote setting can be translated by way of the translational means (6) into a swivelling movement of the gripper arms (4) relative to the basic body (3) and vice versa,

   characterised in that

   sides (9) of the hook sections (8) facing each other comprise at least one oblique area (12), within which the sides (9) are designed so converge in an oblique manner,

   wherein a distance (36) between end points (40) of the sides (9) of the gripper arms (4) facing away from the basic body (3), is greater than a distance (34) between close points (33) of the sides (9) which are arranged on an end of the sides (9) facing the basic body (3).
2. Gripping device (1) according to claim 1, characterised in that the distance (36) between the end points (40) is greater than 14.5 cm, preferably greater than 15.0 cm, more preferably greater than 15.5 cm.
3. Gripper device (1) according to any one of the preceding claims, characterised in that the distance (34) between the near points (33) is smaller than 14.5 cm, preferably smaller than 12.0 cm, more preferably smaller than 9.0 cm.
4. Gripper device (1) according to any one of the preceding claims, characterised in that the swivel axes (10, 11) of the gripper arms (4) are at a distance from one another, wherein preferably the basic body (3) interacts with at least two translational means (6) each of which is assigned to one of the gripper arms (4) .
5. Gripping device (1) according to the preceding claims, characterised in that the gripper arms (4) each comprise at least one guide groove (14), each of which interacts with a translational means (6) wherein preferably when the gripper arms (4) are located in their closed position, in a plane orientated perpendicularly to the swivel axes (10, 11), projections from each of the longitudinal axes (15) of the guide grooves (14) and the axis of action (13) of the operating element (5) jointly form an angle (16) of between 1° and 45°, preferably between 5° and 35°, more preferably between 10° and 25°.
6. Gripping device (1) according to any one of the preceding claims, characterised in that the gripper arms (4) each comprise at least one guide groove (14), each of which interacts with a translational means (6) wherein preferably when the gripper arms (4) are located in their open position, in a plane orientated perpendicularly to the swivel axes (10, 11), projections from each of the longitudinal axes (15) of the guide grooves (14) and the axis of action (13) of the operating element (5) jointly form an angle (41) of between 1° and 50°, preferably between 10° and 40°, more preferably between 20° and 30°.
7. Gripper device (1) according to any one of the preceding claims, characterised in that the at least one translational means (6) comprises at least one guide carriage (17), which interacts with the guide groove (14) and can be moved along the latter, so that the movement of the operating element (5) between its near setting and its remote setting is associated with a movement of the guide carriage (17) in the guide groove (14) and consequently with swivelling of the respective gripper arm (4) relative to the basic body (3).
8. Gripping device (1) according to any one of the preceding claims, characterised by a cable pull (43) which is in operative connection with the basic body (3) as well as the operating element (5), so that by way of operating the cable pull (43) the operating element (5) can be moved from its remote setting into its near setting.
9. Gripping device (1) according to any one of the preceding claims, characterised by an elongated push rod (18) which is, or can be, connected to the basic body (3) in a force-transmitting manner, wherein preferably a length of the push rod (18) considerably exceeds a length of a respective gripper arm (4) measured in the direction of the axis of action (13), preferably by at least two-fold, more preferably by at least three-fold.
10. Gripping device (1) according to any one of the preceding claims, characterised by at least one restoring element, more particularly a compression spring (21), that is arranged between the basic body (3) and the operating element (5), wherein preferably the restoring element is pretensioned with a compression force.
11. Gripping device (1) according to any one of the preceding claims, characterised by at least one support element (22) that is arranged on a lower side (23) of the rest of the gripping device (1), so that when the gripping device (1) is placed on a substrate, the support element (22) comes into direct contact therewith, through which the gripper arms (4) can be stored at a distance (24) from the substrate that is equivalent to a height (25) of the support element (22).
12. Method of gripping a transporting pallet, comprising the following process stages:

    a) A gripping device (1) that comprises at least two gripper arms (4) arranged on a basic body (3), is moved in the direction towards the transporting pallet, wherein the gripper arms (4) each comprise at least one hook section (8), wherein sides (9) of the hook sections (8) facing each other each have at least one oblique area (12), within which the sides (9) are designed to converge in an oblique manner, wherein a distance (36) between the end points (40) of the sides (9) of the gripper arms (4) facing away from the basic body (3) is greater than a distance (34) between close points (33) of the sides (9) that are arranged on an end of the sides (9) facing the basic body (3).

    b) The gripper arms (4) are brought into contact with a pallet base (2) of the transporting pallet in such a way that the oblique areas (12) of the sides (9) of the hook sections (8) come into contact with the pallet base (2), through which the gripper arms (4) are pushed away from each other and in this way the gripper arms (4) are moved into an open setting.

    c) The gripper device (1) is moved further in the direction of the transport pallet until at least the hook sections (8) of the gripper arms (4) are moved out beyond a rear area (28) of the pallet base (2) opposite the basic body (3).

    d) An operating element (5) that interacts with the gripper arm (4) by means of at least one translational means (6), is moved relative to the basic body (3) along an axis of action (13) in a direction away from the basic body (3) as well as the transporting pallet, wherein this movement is converted by means of the translational means (6) into a swivel movement of the gripper arms (4) and through this the latter are moved from their open setting into their closed setting, so that the hook sections (8) of the gripper arms (4) engage with the rear area (28) of the pallet base (2).
13. Method according to claim 12, characterised in that as a result of the contact with the pallet base (2), the gripper arms (4) are swivelled relative to the basic body (3) about a swivel axis (10, 11) and in this way are moved from their closed setting into an open setting.
14. Method according to claim 12 or 13 characterised in that during the movement of the gripper arms (4) into their open setting, at least one restoring element, preferably in the form of a compression spring (21), is tensioned, so that at the moment of moving the hook sections (8) beyond the rear area (28) of the pallet base (2), through the effect of a restoring force stored in the restoring element, the gripper arms (4) are automatically moved in the direction of their closed setting.
15. Method according to any one of claims 12 to 14 characterised in that by means of moving the operating element (5) towards the basic body (3), through the action of the at least one translational means (6), the gripper arms (4) are moved out of their closed setting into their open setting, so that the engagement between the gripping device (1) and the pallet base (2) is released.

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