--- publication_id: "OT-2026-000086428" title: "Three bellows cup vacuum gripper, three zone face, common isolation valve, pump fed, sustained blow-off before set-down" published_at: "2026-09-17T09:02:14.823225Z" canonical_url: "https://opentechnical.org/p/OT-2026-000086428" categories: - "robotics-automation/end-effectors/vacuum-grippers" - "sensors-controls-machine-vision/position-and-presence-sensing" - "industrial-motion-power-transmission/fluid-power/valves-and-manifolds" - "industrial-motion-power-transmission/fluid-power/vacuum-generation" keywords: - "zoned vacuum tool" - "mounting flange" - "bellows cup" - "vacuum pump" - "isolation valve" - "zone branch" - "contact detector" - "blow-off valve" - "blow off release" - "common isolation" --- # Three bellows cup vacuum gripper, three zone face, common isolation valve, pump fed, sustained blow-off before set-down ## Abstract A zoned vacuum gripping tool comprising one mounting flange, three bellows cups, one vacuum pump, one isolation valve, three zone branches, one contact detector and one blow-off valve. When the bellows cups reach the workpiece, the bellows cups are evacuated by the vacuum pump. 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 zoned vacuum gripping tool: three bellows cups carried on a mounting flange, fed by a vacuum pump. 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, clearing the face at release and taking up height differences at the face. 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 bellows cups.** Each bellows cup is folded so that it shortens under vacuum and takes up a height difference between the face and the workpiece. The count of three follows from the arrangement: one gripping element per zone branch. Each bellows cup has three folds. [0004] **One vacuum pump.** The pump draws the circuit down mechanically and adds its own mass to the moving assembly. [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 frame. [0008] **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 sustained blast. The blow-off pulse is given before set-down. [0009] The bellows cups are carried on the tool side of the mounting flange. [0010] The vacuum pump is fixed to the tool side of the mounting flange. [0011] The isolation valve is placed in the line from the vacuum pump, so that closing the valve cuts the whole circuit from the supply. [0012] 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. [0013] Each bellows cup is connected to its own zone line, one bellows cup per zone, and is evacuated through that line. [0014] The contact detector is mounted on the frame and reports the moment a workpiece is present against the gripping face. [0015] The blow-off valve is connected to the circuit at the line downstream of the isolation valve, so that compressed air can be driven back through the circuit to the face. [0016] The robot side of the mounting flange is bolted to the robot flange. [0017] The pump motor is supplied from the electrical supply of the cell. [0018] The blow-off valve is fed from the compressed air supply of the cell. [0019] The isolation valve and the blow-off valve are switched by the cell controller; the contact detector reports to the cell controller. ## 3. Operating sequence and conditions - After the contact detector has detected the workpiece, the vacuum supply is actuated by the cell controller. - When the bellows cups reach the workpiece, the bellows cups are evacuated by the vacuum pump. - After the bellows cups have reached the workpiece, the isolation valve is closed by the cell controller. - While the isolation valve is in the closed state, the vacuum downstream of the valve is maintained by the sealed gripping face. - 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 workpiece is held until the blow-off valve has opened the circuit. [0026] The cell controller reads the contact detector (on the frame) and commands the blow-off valve, the isolation valve; no sensor drives an actuator directly. ## 4. Parameters and operating assumptions [0027] Parameter values of this embodiment: folds of the bellows cups: three (sets the travel taken up between the face and the workpiece, and the lateral stiffness of the cup under load); material of the bellows cups: plastic (sets the friction at the lip and the resistance of the folds to fatigue); drive medium of the vacuum pump: electric (sets the supply the pump motor needs from the cell); 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 frame (sets where the presence of the workpiece is detected); duration of the blow-off valve: a sustained blast (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). [0028] 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. [0029] The blow-off is a sustained blast: the valve stays open for the whole release so that the face is cleared of dust and the workpiece is pushed positively away. ## 5. Provenance and status [0030] 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-4489564-B1, US-10163334-B1, US-10549431-B2, US-11427405-B1, US-2022339798-A1, US-8132312-B2, WO-2026020244-A1; their text is not reproduced, and the description above is generated from the structure of the combination.