High pressure can testing apparatus

Claim 2

Apparatus for detecting can leakage comprising conveyor means for moving cans from a can charging station to a can discharging station; a plurality of test pockets provided on said conveyor means; means for charging cans into the test pockets; means for sealing the interior of the cans from the environment of the test pockets and the environment of the test pockets from the atmospheric environment; means for injecting gas under pressure into the interior of the cans; conduit means between the gas injection means and the cans, for conveying gas from the injection means to the can; a first series of spool valves interposed between the gas injection means and the test pockets for opening or closing the conduit means to passage of gas therethrough; stationary means for sensing pressure increase in the test pocket; conduit means between the sensing means and the test pockets for conveying gas from the test pocket to the sensing means; and a second series of spool valves interposed between the test pockets and the sensing means for opening or closing the conduit means to passage of gas therethrough.

Claim 3

Apparatus of claim 1 including a rotatable shaft and a valve ring for operatively receiving said second series of spool valves, the conveyor means being a spider wheel mounted on the shaft for rotation therewith.

Claim 4

Apparatus of claim 2 wherein first and second series of valves are mounted on both sides of the spider wheel for rotation therewith, the first series of spool valves being rotatably disposed on the gas injection side of the apparatus while the second series of spool valves being operatively disposed in transverse bores of the valve ring disposed on the leak detection side of the apparatus.

Claim 5

Apparatus of claim 3 wherein the first series of spool valves on the air injection side includes two recessed portions in each of the spool valves forming chambers within the bore, said apparatus including a pair of passages communicating with one of the chambers when the spool valve is in the open position to allow the gas to pass through the valve ring into a can, a third passage in communication with one of the chambers to allow exhausting of the test gas from the can when the spool valve is in the closed position and means for displacing the first series of spool valves into open and closed positions; and wherein on the leak detection side, the second series of spool valves includes a recess forming a chamber within the bore, said apparatus including a pair of passages in communication with the chamber to permit leaking gas from a can to pass to the sensing means and means for displacing the second series of spool valves into open and closed positions.

Claim 6

Apparatus of claim 4 wherein the number of spool valves in the first and second series is equivalent, the number corresponding to the number of test pockets on the apparatus.

Claim 7

Apparatus of claim 5 wherein spool valves on the gas injection side are three-way valves, the apparatus comprising means for displacing spool valves on the gas injection side which includes a pair of abutments, means for displacing the pair of abutments to a position to either open or close the spool valves, means for actuating the pair of abutments in unison, and a sinGle abutment rigidly mounted at a point spaced from the pair of abutments and passed the station where the leak detection test is made, for displacing the spool valves to a closed position to allow the can to be vented; and wherein said apparatus also includes means for displacing spool valves on the leak detection side, these valves being two-way valves, the displacing means including a first abutment rigidly mounted on the leak detection side at a point between the pair of abutments and the single abutment on the gas injection side, the first abutment serving to open the two-way spool valves to permit communication between the test pockets and the sensing means; and a second abutment spaced from the first abutment for moving the two-way spool valves to a closed position.

Claim 8

Apparatus of claim 6 wherein on the gas detection side, the pressure sensing means is in airtight, slidable engagement with the valve ring, the openings on one side of the valve ring come into successive alignment with the sensing means while the openings on the opposite side of the valve ring are in operative engagement with the conduit means between the sensing means and the test pockets.

Claim 9

Apparatus of claim 6 including means having a plurality of cavities for feeding cans to the conveying means, the cavities being provided for reception of cans; means for detecting absence of a can in a cavity; means for actuating the pair of abutments on the gas injection side to move the three-way spool valves to a closed position in response to a signal from the detecting means.

Claim 10

Apparatus of claim 8 wherein said actuating means is a shift register having a plurality of relay stations, the number of stations being related to position of the two abutments in order to time actuation of the two abutments when an empty test pocket arrives to receive pressurized gas into empty test pocket.

Claim 11

Apparatus of claim 9 including a rotatable pulse generator in association with said shift register whose movement is synchronized with movement of the can feeding means, the pulse generator being provided for the purpose of producing pulses in response to movement of the cavities in the can feeding means which pulses are conveyed to said shift register to relay the signal from the first station to the last.

Claim 12

Apparatus for detecting can leakage comprising conveyor means for moving cans from a can charging station to a can discharging station; a plurality of test pockets on the conveyor means; means for charging cans into the test pockets; means for sealing the interior of the cans from the environment of the test pockets and the environment of the test pockets from the atmospheric environment; means for injecting gas under pressure into the interior of the cans; first series of spool valves interposed between the gas injection means and the test pockets for controlling passage of gas into cans disposed in test pockets; means for sensing pressure increase in the test pockets; and a second series of spool valves interposed between the test pockets and the sensing means for controlling passage of gas from the test pockets to the sensing means.

Claim 13

Apparatus for detecting can leakage comprising conveyor means for moving cans from a can charging station to a can discharging station; a plurality of test pockets on the conveyor means; means for charging cans into the test pockets; means for sealing the interior of the cans from the environment of the test pockets and the environment of the test pockets from the atmospheric environment; means for injecting gas under pressure into the interior of the cans; first series of spool valves interposed between the gas injection means and the test pockets for controlling passage of gas into cans disposed in test pockets; means for sensing pressure increase in the test pockets; and a second series of spool valves interposed between the test pockets and the sensing means for controlling passage of gas from the test pockets to the sensing means.

Claim 14

Apparatus of claim 11 including a first valve ring for receiving the first series of spool valves and a second valve ring for receiving the second series of spool valves, the first and second valve rings are mounted on the conveyor means, the conveyor means including a shaft and a spider wheel mounted on the shaft for rotation therewith.

Claim 15

Apparatus of claim 12 including three passages in the first valve ring for each of the spool valves, one being in communication with the gas injection means, another being in communication with interior of a can being tested and the third passage leading to the atmosphere; two recessed portions on each of the spool valves of the first series forming chambers with the first valve ring, with two of the passages being in communication with one of the chambers at a time depending whether the spool valve is in an open or closed poSition; means for displacing the first series of spool valves to an open or closed position; a recess in each of the spool valves of the second series forming a chamber with the second valve ring; a pair of passages in the second valve ring for each of the spool valves which permit leaking gas from the test pockets to pass to the sensing means; and means for displacing the second series of spool valves to an open or closed position.

Claim 16

Apparatus of claim 13 wherein the displacing means for the first series of spool valves includes a pair of stationary abutments on the gas injection side with the spool valves being disposed therebetween as they rotate with the first valve ring; means for displacing in unison the pair of abutments to a position for either opening or closing the spool valves; a single stationary abutment mounted on the same side as but at a point spaced from the pair of abutments and beyond the station where the leak test is made, the single abutment being provided for displacing the spool valves to a closed position so as to allow the interior of the cans to be vented; second means for displacing the second series of spool valves disposed on the leak detection side, this displacing means including a first stationary abutment mounted on the leak detection side between the pair of abutments and the single abutment on the gas injection side and second abutment spaced from the first abutment also disposed on the leak detection side, the first abutment serving to open spool valves while the second abutment serving to close the spool valves.