Abstract
A zoned vacuum gripping tool comprising one mounting flange, one foam pad, one plant vacuum connection, four zone branches, one pressure sensor and one vent valve. When the foam pad reaches the workpiece, the foam pad is evacuated by the plant vacuum connection. After the workpiece has reached the set-down position, the vacuum circuit is vented by the vent valve. 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 zoned vacuum gripping tool: one foam pad carried on a mounting flange, fed by a plant vacuum connection. It is arranged for handling workpieces that do not cover the whole gripping face, verifying that the workpiece is held before the arm moves, controlling the moment of release and holding a workpiece that a rigid lip cannot seal against. 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 mounting flange. The mounting flange carries the whole assembly and presents the bolt pattern that meets the robot.
[0003]One foam pad. The 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 pad is of closed 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]Four zone branches. Each zone branch carries the vacuum of one zone of the face and no other. The count of four follows from the arrangement: one branch per zone. The distribution is divided into four zones, each fed by its own branch.
[0006]One pressure sensor. The pressure sensor taps the line it is placed in and reports the vacuum level in that line. The pressure is measured in the supply line.
[0007]One vent valve. The vent valve opens the circuit it is connected to towards atmosphere, which ends the grip. The circuit is vented after set-down.
[0008]The foam pad is carried on the tool side of the mounting flange.
[0009]The four zone branches are taken from a branch junction on the plant vacuum connection, so that each branch carries the vacuum of its own zone only.
[0010]Each zone line opens into its own section of the distribution chamber behind the porous face of the foam pad, so that the pad is evacuated zone by zone.
[0011]The pressure sensor is tapped into the line between the plant vacuum connection and the distribution and reads the pressure of the whole circuit.
[0012]The vent valve is connected to the circuit at the plant vacuum connection and opens that circuit to atmosphere when it is actuated.
[0013]The robot side of the mounting flange is bolted to the robot flange.
[0014]The vent valve is switched by the cell controller; the pressure sensor reports to the cell controller.
3. Operating sequence and conditions
[0015]
- When the foam pad reaches the workpiece, the foam pad is evacuated by the plant vacuum connection.
[0016]
- When the vacuum level exceeds the gripping threshold, a secure grip is signalled by the pressure sensor.
[0017]
- The workpiece may not be lifted unless the pressure sensor signals a secure grip.
[0018]
- After the workpiece has reached the set-down position, the vacuum circuit is vented by the vent valve.
[0019]
- The workpiece is held until the vent valve has opened the circuit.
[0020]The cell controller reads the pressure sensor (the common supply line) and commands the vent valve; no sensor drives an actuator directly.
4. Parameters and operating assumptions
[0021]Parameter values of this embodiment: material of the foam pad: sponge (sets the compliance of the sealing face); porosity of the foam pad: closed cell (sets whether air passes through the pad body or only through openings cut through it); material of the zone branches: plastic; zones of the zone branches: four (sets how much of the face can be treated separately); placement of the pressure sensor: in the supply line (sets where in the circuit the reading is taken and what it describes); timing of the vent valve: after set-down (sets whether the workpiece is released before or after it is supported by the set-down surface).
[0022]The closed-cell foam does not pass air through its body; the face is evacuated through openings cut through the pad into the distribution chamber, and the foam around each opening forms the seal against the workpiece.
[0023]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.
[0024]Vacuum levels are stated as gauge pressure below atmosphere. A stronger vacuum is a larger pressure difference below atmosphere, and the vacuum level 'exceeds the gripping threshold' when that difference is at least the threshold difference.
5. Provenance and status
[0025]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-10549431-B2, US-11427405-B1, WO-2008134339-A4, WO-2026020244-A1; their text is not reproduced, and the description above is generated from the structure of the combination.
6. Correction notice
[0026]This publication supersedes OT-2026-000006187, whose text described this arrangement with defects recorded in the quality register at https://opentechnical.org/qa/. The earlier publication is unchanged and remains public. Changes made to reach a consistent configuration: sensor placement moved from an absent manifold to the supply line; release element added: a vent valve after set-down (the legacy assembly had no way to let go).