Abstract
A zoned vacuum gripping tool comprising one mounting flange, three bellows cups, one vacuum pump, three isolation valves, three zone branches, one pressure sensor and one vent valve. When the bellows cups reach the workpiece, the bellows cups are evacuated by the vacuum pump. 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: 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, verifying that the workpiece is held before the arm moves, controlling the moment of 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 one fold.
[0004]One vacuum pump. The pump draws the circuit down mechanically and adds its own mass to the moving assembly.
[0005]Three isolation valves. Each isolation valve sits in the line it controls; closing it cuts that line without disturbing the rest of the circuit. The count of three follows from the arrangement: one valve per zone branch. Isolation is per zone.
[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 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.
[0008]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.
[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 three zone branches are taken from a branch junction on the pump inlet line, so that each branch carries the vacuum of its own zone only.
[0012]One isolation valve is placed in each zone branch, so that closing that valve cuts its zone from the circuit and leaves the other zones under vacuum.
[0013]Each bellows cup is connected to its own zone line, one bellows cup per zone, and is evacuated through that line.
[0014]The pressure sensor is tapped into the line between the vacuum pump and the distribution and reads the pressure of the whole circuit.
[0015]The vent valve is connected to the circuit at the pump inlet line and opens that circuit to atmosphere when it is actuated.
[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 isolation valves and the vent valve are switched by the cell controller; the pressure sensor reports to the cell controller.
3. Operating sequence and conditions
[0019]
- When the bellows cups reach the workpiece, the bellows cups are evacuated by the vacuum pump.
[0020]
- When the vacuum level exceeds the gripping threshold, a secure grip is signalled by the pressure sensor.
[0021]
- The workpiece may not be lifted unless the pressure sensor signals a secure grip.
[0022]
- When a zone is not covered by the workpiece, the isolation valve of that zone is closed by the cell controller.
[0023]
- While the isolation valve of that zone is in the open state, the vacuum of a covered zone is maintained by the vacuum pump.
[0024]
- After the workpiece has reached the set-down position, the vacuum circuit is vented by the vent valve.
[0025]
- The workpiece is held until the vent valve has opened the circuit.
[0026]The cell controller reads the pressure sensor (the common supply line) and commands the isolation valves, the vent valve; no sensor drives an actuator directly.
4. Parameters and operating assumptions
[0027]Parameter values of this embodiment: folds of the bellows cups: one (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 valves: per zone (sets which part of the circuit the valve cuts: one branch line on its own or the whole circuit); material of the isolation valves: 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 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).
[0028]Which zones the workpiece covers is known to the controller from the workpiece programme; the arrangement provides the valve per zone and the controller decides which valves to close.
[0029]A zone whose isolation valve is closed is cut from the common line and does not vent or blow off until its valve opens.
[0030]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
[0031]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, 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
[0032]This publication supersedes OT-2026-000005303, 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).