Abstract
A foam-pad vacuum gripping tool comprising one tool-change interface, two foam pads, one plant vacuum connection, one manifold, one contact detector and one blow-off valve. When the foam pads reach the workpiece, the foam pads are evacuated by the plant vacuum connection. Before the workpiece reaches the set-down position, the workpiece is blown off by the blow-off valve while the workpiece is above the receiving surface. The arrangement is a proposed configuration composed from a typed library of mechanism blocks derived from published patents; it has not been constructed.
1. Purpose and arrangement
[0001]This disclosure describes a foam-pad vacuum gripping tool: two foam pads carried on a tool-change interface, fed by a plant vacuum connection. It is arranged for starting the cycle at the moment of contact, clearing the face at release, holding a workpiece that a rigid lip cannot seal against and exchanging the tool without rewiring the cell. One concrete embodiment is described; every connection is stated with the medium it carries, and the operating sequence is given as conditions on named operations.
2. Components, construction and connections
[0002]One tool-change interface. The tool-change interface splits the tool into a robot side and a tool side, so the tool can be exchanged without dismantling it. The tool-change interface has a pneumatic lock.
[0003]Two foam pads. Each foam pad presents a compliant face to the workpiece; the holding force is spread over the contact area rather than concentrated at a lip. The count of two follows from the arrangement: one gripping element per manifold outlet. The pad is of open cell foam.
[0004]One plant vacuum connection. The plant vacuum connection takes vacuum from the plant line, so the tool carries no generator of its own.
[0005]One manifold. The manifold receives the vacuum at one inlet and distributes it to its outlets. The manifold has two outlets.
[0006]One contact detector. The contact detector reports the moment a workpiece is present at the gripping face; its sensing technology is not fixed by this arrangement. The contact detector is mounted on the frame.
[0007]One blow-off valve. The blow-off valve drives compressed air back through the circuit to the face, which clears the face instead of waiting for the circuit to refill. The blow-off is a short pulse. The blow-off pulse is given before set-down.
[0008]The foam pads are carried on the tool side of the tool-change interface.
[0009]The manifold is fixed to the tool side of the tool-change interface.
[0010]The manifold inlet is connected to the plant vacuum connection, which supplies every outlet of the manifold.
[0011]Each manifold outlet feeds one foam pad by its own vacuum line, so that the two outlets feed two foam pads.
[0012]The contact detector is mounted on the frame and reports the moment a workpiece is present against the gripping face.
[0013]The blow-off valve is connected to the circuit at the plant vacuum connection, so that compressed air can be driven back through the circuit to the face.
[0014]The robot side of the tool-change interface is bolted to the robot flange.
[0015]The blow-off valve is fed from the compressed air supply of the cell.
[0016]The locking piston of the tool-change interface is fed from the compressed air supply of the cell.
[0017]The blow-off valve and the lock of the tool-change interface are switched by the cell controller; the contact detector reports to the cell controller.
3. Operating sequence and conditions
[0018]
- After the contact detector has detected the workpiece, the vacuum supply is actuated by the cell controller.
[0019]
- When the foam pads reach the workpiece, the foam pads are evacuated by the plant vacuum connection.
[0020]
- Before the workpiece reaches the set-down position, the workpiece is blown off by the blow-off valve while the workpiece is above the receiving surface.
[0021]
- The workpiece is held until the blow-off valve has opened the circuit.
[0022]The cell controller reads the contact detector (on the frame) and commands the blow-off valve, the tool-change interface; no sensor drives an actuator directly.
4. Parameters and operating assumptions
[0023]Parameter values of this embodiment: locking of the tool-change interface: pneumatic (sets what has to be present at the interface for the tool to stay attached); material of the foam pads: sponge (sets the compliance of the sealing face); porosity of the foam pads: open cell (sets whether air passes through the pad body or only through openings cut through it); outlets of the manifold: two (sets how many lines can be fed from one inlet); placement of the contact detector: on the frame (sets where the presence of the workpiece is detected); duration of the blow-off valve: a short pulse (sets how quickly the face clears and how much air each release costs); timing of the blow-off valve: before set-down (sets whether the pulse assists a drop release or clears the face after set-down).
[0024]The workpiece is released while it is still above the receiving surface and falls the remaining distance onto it. This sequence is for a workpiece and a receiving surface that tolerate that drop, for example a part released into a container or onto a conveyor; the drop height is set by the application and is not fixed here.
[0025]The blow-off is a short pulse: the valve opens for a fraction of a second, long enough to break the seal and clear the face, and closes again.
[0026]The open-cell foam passes air through its whole face, so an uncovered part of the face draws air through the pad itself; the supply is sized for that continuous flow and the pad relies on flow restriction through the foam, not on a seal, to hold vacuum behind a covered area.
[0027]The tool carries no valve between the plant line and the face, so the plant vacuum is applied to the face whenever the plant line is live; release relies on the release element alone.
[0028]The lock is engaged by compressed air acting on the locking piston and is held only while that air pressure is applied; what the lock does on loss of air pressure is not fixed by this arrangement.
5. Provenance and status
[0029]This document is an original combination composed from a typed library of mechanism blocks. Each block was derived from a published patent and carries typed connection points, the parameters its source states, and its own construction and operating description. The combination described here is proposed and has not been constructed. The published documents behind the blocks used in this arrangement are EP-4385681-B1, US-10259123-B2, US-11858125-B2, US-2022339798-A1, US-8006968-B2, US-8132312-B2; their text is not reproduced, and the description above is generated from the structure of the combination.