Device for holding objects

Abstract

The invention relates to a device for holding objects, wherein the device has a ring-shaped profiled mat (2) which contains granular material (4) and surrounds a suction chamber (6) which is open to at least one side, wherein the profiled mat (2) and the suction chamber (6) have an interface (12, 26) for a negative pressure source, characterized in that at least one annular sealing lip (32), preferably at least two annular sealing lips (32), are arranged on the profiled mat (2).

Description

Technical Field

[0001] The present invention relates to a device for holding an object, wherein the device has an annular molding pad containing particulate matter and surrounding a suction cavity open to at least one side, wherein the molding pad and the suction cavity have an interface for a negative pressure source. Background Technology

[0002] Such devices are known in the prior art and are used to hold, manipulate, and / or transport objects. To hold an object using this device, the forming pad is brought into contact with the object. The forming pad is made of a flexible and / or elastic material, thus deforming under pressure applied by the object. This causes particles located within the forming pad to move. Subsequently, a negative pressure is applied to the forming pad. This negative pressure comes from a negative pressure source, such as a pump, which may be part of the device, but is not required to be. Such devices are commonly used in production workshops as end effectors for robots, which may be connected to a central negative pressure supply system or have their own pumps. By applying negative pressure to the forming pad, air is extracted from the pad, and the pad hardens in the area where it contacts the workpiece to be grasped. In this way, the device can adapt very well to the external shape, geometry, and / or form of the object.

[0003] Such devices initially feature a molding pad with a large end facet, which preferably rests in full contact with the object to be held, allowing the molding pad to deform. A further development of such devices features an annular molding pad. The annular molding pad can be designed to be ring-shaped, although this is not mandatory. "Annular" means that the cross-section through the molding pad has a closed outer contour and a closed inner contour. The outer contour is formed, for example, by an outer wall, and the inner contour by an inner wall. Between the inner and outer walls is a volume for accommodating particles. One side of the molding pad is fixed to a retainer for mounting the device to another component, such as a robotic arm. On the opposite side, the molding pad is defined by the end facet. Typically, the end facet is configured to contact the object to be held.

[0004] The suction chamber is located within the inner wall, surrounded by a molding pad and defined by the inner wall of the molding pad. The suction chamber has an interface for a negative pressure source. This interface is preferably located on the side of the suction chamber facing the device holder. On the opposite side, facing the object to be held, the suction chamber is open.

[0005] When holding an object, the negative pressure applied to the forming pad hardens the pad, thus holding it in the shape adapted to the object. The negative pressure applied to the suction chamber creates a suction effect on the object to be held. This force holds the object on the device.

[0006] The aforementioned characteristics and features are not only present and advantageous in prior art devices, but also advantageous for devices according to embodiments of the present invention.

[0007] The drawback is that such devices require a high level of suction to safely hold the object. This can be achieved, for example, by using a pump that must run continuously to maintain the required suction force during holding. This results in high energy consumption and therefore relatively high costs. Summary of the Invention

[0008] Therefore, the objective of this invention is to further improve this type of device so that it has a lower energy requirement.

[0009] The present invention solves the proposed task by means of an apparatus having preferred technical features, wherein at least one annular sealing lip, preferably at least two annular sealing lips, are arranged on the molding pad.

[0010] This invention is based on the understanding that the high energy consumption of existing devices is at least partly due to insufficient sealing between the molding pad and the object to be held, even though the molding pad is almost optimally adapted to the object's contour, shape, and form when negative pressure is applied. Because of this insufficient sealing, air flows into the suction chamber under negative pressure, causing a pressure drop. This pressure drop means a reduced pressure difference between the negative pressure provided by the negative pressure source and the ambient pressure. The negative pressure within the suction chamber is thus weakened, and the pressure within the suction chamber increases. This leakage is reduced or even completely avoided by the sealing lip of this invention, making it easier to maintain the pressure difference between the suction chamber pressure required to hold the object and the ambient pressure, and therefore reducing energy consumption.

[0011] The sealing lip is designed to be annular. This can mean circular, but is not mandatory. In the sense of this invention, any closed contour or path extending along it is considered annular.

[0012] Preferably, the molding pad has an inner wall facing the suction cavity, an outer wall facing away from the suction cavity, and an end side or end face connecting the inner wall and the outer wall, wherein the sealing lip is disposed at the end side. The end side typically faces the object to be held. Preferably, the annular sealing lip extends around an opening leading to the suction cavity.

[0013] In a preferred embodiment, the sealing lip is integrally or one-piece with the molding pad. The molding pad with the sealing lip can be made, for example, by casting, wherein both the shape of the molding pad and the shape of the sealing lip are present in the mold and are cast.

[0014] Alternatively, the sealing lip can also be fixed to the molding pad, for example, by bonding, welding, or other means. Advantageously, the connection between the sealing lip and the molding pad is made as airtight as possible along the entire extension path of the sealing lip to avoid the aforementioned leakage.

[0015] The end face of the molding pad is annular. This can be a ring, but it is not mandatory. Importantly, the end face forms an opening leading to the suction cavity. The ring formed by the end face has a width corresponding to the distance between the inner and outer walls. Preferably, this width is constant in the circumferential direction. The end face has a radially inner portion and a radially outer portion. The radially inner portion is preferably the radially inner half, radially inner third, or radially inner quarter of the end face. The radially inner portion is the portion of the end face that adjoins the edge of the inner wall. The radially outer portion is preferably the radially outer half, radially outer third, or radially outer quarter of the end face. The radially outer portion is the portion of the end face that adjoins the edge of the outer wall.

[0016] Preferably, the sealing lip is disposed in the radially inner portion of the end side. This has the advantage of positioning the sealing lip close to the suction chamber where negative pressure is applied, which needs to be sealed from the environment. Furthermore, this arrangement allows for the use of a relatively long sealing lip that does not protrude radially outward from the molding pad.

[0017] In a preferred embodiment, the sealing lip does not protrude radially outward from the molding pad.

[0018] Preferably, the sealing lip has a first portion in which it bends away from the molding pad. The sealing lip also has a second portion in which it bends toward the molding pad. In this way, it can be used as a spacer between the molded end and the object to be held, so that the sealing lip is also subjected to negative pressure applied to the suction chamber.

[0019] It has proven advantageous that the molding pad and the suction chamber can be subjected to negative pressure separately from each other.

[0020] Preferably, the molding pad and the suction chamber have a common interface for a negative pressure source, wherein the device preferably has a valve through which negative pressure can be distributed to the molding pad and / or the suction chamber. Thus, the device has a separate interface on which the negative pressure source can be located, and when the negative pressure source is connected to this interface, both the molding pad and the suction chamber can be subjected to negative pressure through this interface. Branch lines branch off from this interface to the molding pad and to the suction chamber. Both branch lines are part of the common line originating from this interface. The valve is preferably located at the branch point. The valve is preferably configured to supply negative pressure only to the molding pad or only to the suction chamber. Furthermore, the valve is preferably configured to supply negative pressure to both the molding pad and the suction chamber, wherein the valve is particularly preferably capable of supplying negative pressure to the molding pad and the suction chamber to different degrees. This can be achieved, for example, by the valve changing the flow resistance in the branch line to the molding pad and the flow resistance in the branch line to the suction chamber. This can be achieved, for example, by one or more throttling valves.

[0021] A method for holding an object, comprising using a device according to an embodiment of the invention, the method itself constituting an independent invention. In this method, a molding pad is first adapted to the geometry, external shape, and / or morphology of the object to be held. This is preferably achieved by bringing the molding pad into contact with the object. Here, the molding pad is not subjected to negative pressure. It is flexible and deformable, thus adapting to the object.

[0022] In this state, a negative pressure is applied to the suction chamber. Thus, a holding force is applied to the object at this early stage, which can also cause the molding pad to further adapt to the shape, geometry, and / or form of the object.

[0023] After this deformation of the molding pad, a negative pressure is applied to it. As described above, the molding pad loses its flexibility and is fixed in its adopted shape. Because a negative pressure has been applied to the suction chamber, movement of the molding pad relative to the object during the hardening process is also prevented.

[0024] The process of releasing the object from the device is preferably performed in reverse. After the object has been held for a sufficient period of time, the negative pressure applied to the suction chamber is first stopped. For this purpose, it is sufficient to close the valve in the pipeline through which the externally applied negative pressure is directed to the suction chamber. Alternatively, the suction chamber can be ventilated, for example, by opening the connection between the suction chamber and the surrounding environment. Subsequently, the pressure reaches equilibrium, and the holding force on the object generated by the negative pressure within the suction chamber can no longer be maintained. Preferably, after this, or at least at a time offset from it, the application of negative pressure to the molding pad or even its ventilation is stopped.

[0025] Preferably, the suction cavity is covered on its open side by a breathable covering. Through this covering, the suction effect exerted on the object by the negative pressure within the suction cavity, and thus the retaining force, continues to act on the object. In this case, it is referred to in this application as a suction cavity open to one side. With the breathable covering, even very flexible objects will not be sucked into the suction cavity as in the prior art, or at least not as severely, thus avoiding deformation and damage. Preferably, the breathable covering is made of a flexible but non-elastic material. Therefore, it can follow the shape changes of the molding pad during the fitting process.

[0026] Preferably, the breathable covering is made of fabric, and particularly preferably of woven fabric.

[0027] Preferably, the breathable covering is disposed on the molded pad, particularly bonded and / or welded to the molded pad.

[0028] In a preferred embodiment, the molding pad has an inner wall facing the suction cavity, an outer wall facing away from the suction cavity, and an end side connecting the inner wall and the outer wall, wherein the breathable covering is disposed at the edge between the inner wall and the end side.

[0029] Preferably, the breathable cover includes at least one stabilizing strip having higher stiffness, particularly flexural stiffness, than the rest of the breathable cover. Particularly preferably, at least one stabilizing strip extends from the inner wall of the molded pad to the inner wall of the molded pad. Attached Figure Description

[0030] Some embodiments of the device for holding an object are described in more detail below with the aid of the accompanying drawings. The drawings are as follows.

[0031] Figure 1 A schematic cross-sectional view of such a device according to a first embodiment is shown.

[0032] Figure 2 Show Figure 1 A schematic cross-sectional view of the device in contact with an object.

[0033] Figure 3 A schematic cross-sectional view of such a device according to the second embodiment is shown.

[0034] Figure 4 A schematic cross-sectional view of such a device according to a third embodiment is shown.

[0035] Figure 5 Show Figure 4 A schematic cross-sectional view of the device in contact with an object.

[0036] Figure 6 A schematic cross-sectional view of such a device according to the fourth embodiment is shown. Detailed Implementation

[0037] Figure 1 A schematic cross-sectional view of a device for holding an object is shown. The device has an annular forming pad 2 containing particles 4. The forming pad 2 surrounds an annular suction cavity 6, which... Figure 1 The device opens downwards. The molding pad 2 is fixed to the interface member 10 by means of a connecting element 8. The interface member 10 is arranged, for example, on a robot arm (not shown). On the interface member 10, the device has an interface 12 for a negative pressure source, through which air can be drawn from the intermediate space 14 between the interface member 10 and the connecting element 8 when the interface 12 is connected to the negative pressure source. The connecting element 8 has a through hole 16 that connects the intermediate space 14 to the suction chamber 6. Therefore, if a negative pressure is applied at the interface 12 by means of a negative pressure source (e.g., a pump) connected to the interface 12, air is drawn from the intermediate space 14 and from the suction chamber 6 through the through hole 16.

[0038] In the illustrated embodiment, the interface 10 has two valves 18 that, when open, connect the intermediate space 14 to the annular sub-cavity 20. The connecting element 8 has two additional channels 22 that connect the sub-cavity 20 to the molding pad 2. Therefore, when the valves 18 are open, air is also drawn out of the molding pad 2 by a negative pressure source located at the interface 12, and the particles 4 are securely encapsulated by the sheath 24 of the molding pad 2. The interface also has a second interface 26 that can be connected to a negative pressure source. Thus, different negative pressures can be applied to the molding pad 2 and the suction chamber 6 when the valves 18 are closed.

[0039] A stop 28 and a sensor 30 are also arranged in the suction chamber 6, which can be used to monitor the approach of the object to be held. In the sleeve 24... Figure 1 As shown on the lower side, two sealing lips 32 are arranged. This seals the contact area between the sheath 24 of the molding pad 2 and the object to be held. This makes it easier to maintain negative pressure within the suction chamber 6, which exerts a suction force on the object to be held.

[0040] Figure 2 It shows Figure 1 The device is in contact with the object 34. It can be seen that the sealing lip 32 is pressed against the object 34. The object 34 is drawn towards the molding pad 2 by the negative pressure generated within the suction chamber 6. The negative pressure generated in the molding pad ensures that the sheath 24 of the molding pad 2 adheres tightly to the particulate 4, thereby preventing individual components of the particulate 4 from moving relative to each other.

[0041] Figure 3A schematic cross-sectional view of the device according to the second embodiment is shown. The sealing lip 32 has a thickened portion at its end, thereby improving sealing characteristics. The sealing lip 32 is part of the central sealing element 36, which replaces the central portion of the connecting element 8 in defining the suction chamber 6 in the direction toward the interface member 10. The interface 12 is connected to the suction chamber 6 via a conduit 38.

[0042] Figure 4 The third embodiment of the device for holding an object, shown in a schematic cross-sectional view, essentially corresponds to Figure 1 The display. However, Figure 4 The device shown does not have a sealing lip 32. It has a cover 40 that is designed to be breathable and defines a suction chamber 6 in the downward direction, i.e., toward the object to be held. Because the cover 40 is breathable, the negative pressure generated in the suction chamber by a negative pressure source (not shown) arranged at the interface 12 exerts a holding force on the object. Figure 5 and Figure 6 The display corresponds to Figure 2 and Figure 3 .However, Figure 5 and Figure 6 The illustrated embodiments of the device do not have a sealing lip 32. Each of them has a breathable covering.

[0043] List of reference numerals in the attached diagram: 2 Molding Pad 4. Particulate matter 6. Suction chamber 8 Connecting elements 10 Interface components 12 interfaces 14 Intermediate Space 16 through holes 18 valves 20 secondary cavities 22 channels 24-pack 26 Second Interface 28 Stop 30 sensors 32 Sealing Lip 34 objects 36 Sealing elements 38 Piping 40. Coverings.

Claims

1. A device for holding an object, wherein, The device has an annular molding pad (2), the molding pad Contains particulate matter (4), and Surrounding the suction chamber that is open to at least one side (6). The molding pad (2) and the suction chamber (6) have interfaces (12, 26) for a negative pressure source. Its features are, At least one annular sealing lip (32) is arranged on the molding pad (2), preferably at least two annular sealing lips (32).

2. The apparatus according to claim 1, characterized in that, The molding pad (2) has an inner wall facing the suction cavity (6), an outer wall away from the suction cavity (6), and an end side connecting the inner wall and the outer wall, wherein the sealing lip (32) is disposed at the end side.

3. The apparatus according to claim 1 or 2, characterized in that, The sealing lip (32) and the molding pad (2) are formed in one piece.

4. The apparatus according to claim 2 or 3, characterized in that, The sealing lip (32) is disposed in the radially inner portion of the end side.

5. The apparatus according to any one of the preceding claims, characterized in that, The sealing lip (32) does not protrude radially outward from the molding pad (2).

6. The apparatus according to any one of the preceding claims, characterized in that, The sealing lip (32) has a first portion and a second portion, in the first portion the sealing lip is bent away from the molding pad (2), and in the second portion the sealing lip is bent toward the molding pad (2).

7. The apparatus according to any one of the preceding claims, characterized in that, The molding pad (2) and the suction chamber (6) can be subjected to negative pressure separately from each other.

8. The apparatus according to any one of the preceding claims, characterized in that, The molding pad (2) and the suction chamber (6) have a common interface (12) for a negative pressure source, wherein the device preferably has a valve (18) through which negative pressure can be distributed to the molding pad (2) and / or the suction chamber (6).

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