Method and apparatus for testing the tightness of foil bags
AssigneeFocke & Co. (GmbH & Co.)
InventorHeinz Focke
Life of this patent
Estimating the term…
Abstract
Disclosed are a method and apparatus for testing the tightness of foil bags (10). In order to test the tightness of foil bags (10), mechanical testing members are used which act upon the foil bag (10) in the region of a cavity (15) formed above the packaged goods. Testing rams (18) are pushed against a bag wall (16, 17) with a given testing pressure. The depth of impression is indicative of the airtightness of the foil bag ( 10). The size of the cavity (15) which can be used for testing is reduced by clamping members (26) and, as a result, a residual cavity (25) is formed next to the clamping members (26). Consequently, an increased pressure is present within the residiual cavity, that is to say within the foil bag (10), which facilitates testing.
Claims17
A method of testing the air-tightness of foil bags (10) containing packaged goods which only partially fill the interior space of each foil bag (10), said method comprising the following steps:
- a) horizontally moving the foil bags (10) in only a vertically upright position along a conveying path so that the packaged goods collect only in a lower region of each upright foil bag (10), and so that an initial cavity (15) free of the packaged goods is formed in only an upper region of the foil bag and above the packaged goods;
- b) during the movement of the foil bags, first, compressing walls (16, 17) of the bag under action of clamping means only in a laterally adjacent region of said initial cavity (15) to produce, only in said upper region of the bag, a smaller billowed residual cavity (25), as a part of said initial cavity (15), above the packaged goods, said clamping means moving along with the foil bag;
- and
- c) then, also during the compressing and movement of the upright foil bags, testing the foil bags (10) by testing means which act upon said walls (16, 17) of the foil bags and which also move along with the foil bags;
- d) wherein said testing step comprises causing the testing means to act upon the foil bags (10) by exerting pressure on the bag walls (16, 17) of each foil bag only in the region of said residual cavity (25).
An apparatus for testing the air-tightness of foil bags (10) containing packaged goods which only partially fill the interior space of each foil bag (10), said apparatus comprising:
- a) a conveyor for horizontally moving and accommodating the foil bags (10) in only a vertically upright position of the bags along a path so that the packaged goods collect only in a lower region of each foil bag, thereby forming in each bag an upper initial cavity (15) that is free of the packaged goods;
- b) a plurality of bag-clamping means which are movable synchronously along with said conveyor and which act first only in a region of said initial cavity (15) above the goods to clamp together outer walls of each foil bag to form a smaller billowed residual cavity (25) as a part of said initial cavity (15);
- c) a plurality of bag-testing means which also are movable synchronously along with the conveyor, and which act to test the air-tightness of the upright bags while said outer walls are clamped;
- and
- d) wherein said testing means and said clamping means are disposed at approximately the same vertical level and at a location laterally adjacent said initial cavity (15), so that each of the foil bags (10) is first clamped and then tested only in said residual cavity (25) which is located only above the packaged goods and which is free of packaged goods.
Dependencies are inferred from the claim text.