OPENTECHNICAL PUBLICATION OT-2026-000007913 Three cup vacuum gripper, three zone face, common isolation valve, plant vacuum fed, vented before set-down Published: 2026-09-17T08:10:14.564317Z Permanent URL: https://opentechnical.org/p/OT-2026-000007913 Categories: Robotics & Automation > End Effectors > Vacuum Grippers ------------------------------------------------------------------------ ABSTRACT A zoned vacuum gripping tool comprising one mounting flange, three suction cups, one plant vacuum connection, one isolation valve, three zone branches, one contact detector and one vent valve. When the suction cups reach the workpiece, the suction cups are evacuated by the plant vacuum connection. Before the workpiece reaches the set-down position, the vacuum circuit is vented by the vent 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 zoned vacuum gripping tool: three suction cups 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, cutting part of the circuit while the rest holds vacuum, starting the cycle at the moment of contact and controlling the moment of release. 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] Three suction cups. Each suction cup presents a sealing lip to the workpiece and is evacuated through its own connection. The count of three follows from the arrangement: one gripping element per zone branch. The suction cups are of the flat form. [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 isolation valve. The isolation valve sits in the line it controls; closing it cuts that line without disturbing the rest of the circuit. Isolation is common. [0006] Three zone branches. Each zone branch carries the vacuum of one zone of the face and no other. The count of three follows from the arrangement: one branch per zone. The distribution is divided into three zones, each fed by its own branch. [0007] 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 gripping face. [0008] One vent valve. The vent valve opens the circuit it is connected to towards atmosphere, which ends the grip. The circuit is vented before set-down. [0009] The suction cups are carried on the tool side of the mounting flange. [0010] The isolation valve is placed in the line from the plant vacuum connection, so that closing the valve cuts the whole circuit from the supply. [0011] The three zone branches are taken from a branch junction on the isolation valve outlet, so that each branch carries the vacuum of its own zone only. [0012] Each suction cup is connected to its own zone line, one suction cup per zone, and is evacuated through that line. [0013] The contact detector is mounted on the gripping face and reports the moment a workpiece is present against the gripping face. [0014] The vent valve is connected to the circuit at the line downstream of the isolation valve and opens that circuit to atmosphere when it is actuated. [0015] The robot side of the mounting flange is bolted to the robot flange. [0016] The isolation valve and the vent valve are switched by the cell controller; the contact detector reports to the cell controller. 3. Operating sequence and conditions [0017] - After the contact detector has detected the workpiece, the vacuum supply is actuated by the cell controller. [0018] - When the suction cups reach the workpiece, the suction cups are evacuated by the plant vacuum connection. [0019] - After the suction cups have reached the workpiece, the isolation valve is closed by the cell controller. [0020] - While the isolation valve is in the closed state, the vacuum downstream of the valve is maintained by the sealed gripping face. [0021] - Before the workpiece reaches the set-down position, the vacuum circuit is vented by the vent valve while the workpiece is above the receiving surface. [0022] - The workpiece is held until the vent valve has opened the circuit. [0023] The cell controller reads the contact detector (on the gripping face) and commands the isolation valve, the vent valve; no sensor drives an actuator directly. 4. Parameters and operating assumptions [0024] Parameter values of this embodiment: form of the suction cups: flat (sets the shape of the contact area and the behaviour of the lip on a curved workpiece); material of the suction cups: polyurethane (sets the friction at the lip and the tolerance of the lip to oil and heat); control of the isolation valve: common (sets which part of the circuit the valve cuts: one branch line on its own or the whole circuit); material of the isolation valve: steel; material of the zone branches: plastic; zones of the zone branches: three (sets how much of the face can be treated separately); placement of the contact detector: on the gripping face (sets where the presence of the workpiece is detected); timing of the vent valve: before set-down (sets whether the workpiece is released before or after it is supported by the set-down surface). [0025] 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. 5. Provenance and status [0026] 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 US-10163334-B1, US-10259123-B2, US-10549431-B2, US-2016214812-A1, US-2022339798-A1, 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 [0027] This publication supersedes OT-2026-000003591, 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: suction_cup material 'rubber' is not offered by the library; the source-stated value 'polyurethane' is used. ------------------------------------------------------------------------ OpenTechnical publication OT-2026-000007913 Published 2026-09-17T08:10:14.564317Z https://opentechnical.org/p/OT-2026-000007913