Device for temporarily holding articles of different sizes

Claim 2

In an apparatus for temporarily holding objects of different sizes which are to be worked, comprising at least one support surface for holding the objects, said surface being provided with a plurality of openings connected via passage means with a device producing a subatmospheric pressure in such a manner that the objects which are placed onto the supporting surface and which cover at least one of the openings are held against that surface by suction and valve means for each said opening disposed in the passage means and actuated by the subatmospheric pressure to partially seal the passage means in order to prevent excess suction flow when the associated opening in the supporting surface is not sufficiently covered by an object, the improvement wherein said passage means for at least one said opening include: a first passage extending downwardly from, and communicating with, its associated opening; a connecting passage communicating with the lower end of said first passage; a second passage extending upwardly from, and communicating with, said connecting passage and defining a chamber containing said valve means; and a distributor passage communicating with the upper end of said second passage; and wherein said valve means include a valve ball consisting of porous material and a seat for said valve ball formed in the upper end of said chamber, said valve ball being drawn upwardly against said seat under the influence of suction when its associated opening is uncovered and falling downwardly out of contact with said seat due to the reduced air flow when its associated opening is covered.

Claim 3

In an apparatus for temporarily holding objects of different sizes which are to be worked, comprising at least one support surface for holding the objects, said surface being provided with a plurality of openings connected via passage means with a device producing a subatmospheric pressure in such a manner that the objects which are placed onto the supporting surface and which cover at least one of the openings are held against that surface by suction and valve means for each said opening disposed in the passage means and actuated by the subatmospheric pressure to partially seal the passage means in order to prevent excess suction flow when the associated opening in the supporting surface is not sufficiently covered by an object, the improvement wherein said passage means for at least one said opening include: a first passage extending downwardly from, and communicating with, its associated opening; a connecting passage communicating with the lower end of said first passage; a second passage extending upwardly from, and communicating with, said connecting passage and defining a chamber containing said valve means; and a distributor passage communicating with the upper end of said second passage; and wherein said valve means include a valve ball and a seat for said valve ball formed in the upper end of said chamber, said seat being provided with an irregular portion which prevents an air tight fit of the valve ball against said seat, said valve ball being drawn upwardly against said seat under the influence of suction when its associated opening is uncovered and falling downwardly out of contact with said seat due to the reduced air flow when its associated opening is covered.

Claim 4

In an apparatus for temporarily holding objects of different sizes which are to be worked, comprising at least one support surface for holding the objects, said surface being provided with a plurality of openings connected via passage means with a device producing a subatmospheric pressure in such a manner that the objects which are placed onto the supporting surface and which cover at least one of the openings are held against that surface by suction and valve means for each said opening disposed in the passage means and actuated by the subatmospheric pressure to partially seal the passage means in order to prevent excess suction flow when the associated opening in the supporting surface is not sufficiently covered by an object, the improvement wherein said passage means for at least one said opening include: a first passage extending downwardly from, and communicating with, its associated opening; a connecting passage communicating with the lower end of said first passage; a second passage extending upwardly from, and communicating with, said connecting passage and defining a chamber containing said valve means; and a distributor passage communicating with the upper end of said second passage; and wherein said valve means include a valve ball and a seat for said valve ball formed in the upper end of said chamber, said seat being provided with an irregular portion which prevents an air tight fit of the valve ball against said seat, said valve ball being drawn upwardly against said seat under the influence of suction when its associated opening is uncovered and falling downwardly out of contact with said seat due to the reduced air flow when its associated opening is covered.

Claim 5

An arrangement as defined in claim 2 wherein the irregularity is in the form of a groove.