Apparatus and associated method for container sampling for inspection

Abstract: Apparatus for transporting and inspecting containers includes an annealing lehr (54) disposed on one side of a primary conveyor (52) and a stacker (56) having a recip­ rocating pusher bar (58) adapted to transport containers from the primary conveyor into the annealing lehr. Inspection apparatus is positioned adjacent to the primary conveyor. The stacker pusher bar preferably has a series of gates (70-86) which permit a predetermined container which is to be inspected to pass through the pusher bar when the pusher bar is moved toward the annealing lehr to deliver the other containers thereto. The gates may advantageously be slidable or rotatable and be operated on an individual basis by actuators. The inspection equipment may be provided with conveyors to transport the containers to be inspected from the primary conveyor to the inspection apparatus and to transport the inspected containers which pass inspection to the primary conveyor or annealing lehr. A forming machine which molds the containers is connected with the primary conveyor by means of a take-away conveyor. Inspection is accomplished at the hot end of the lehr. In another embodiment, the containers to be inspected are withdrawn from the take-away conveyor, inspected and if acceptable, delivered to the primary conveyor or directly to the lehr. An associated method is provided.

Description: This invention relates to apparatus and an associated method for inspecting containers in an automated sampling manner and, more specifically, with respect to glass containers, effecting said inspection prior to entry of the container into the entry hot end of an annealing lehr. It has long been known to effect automated inspection of containers such as glass containers, for example, either on a continuous basis wherein each container is inspected or on a sampling basis wherein periodically a container is removed in order to inspect for a group of properties which tend to be slow to change. It has been known to measure the volume and shape of a glass gob which was intended to be employed in a glass forming machine. See U.S. Patent 4,205,973. It has also been known to fill the annealing lehr in such a manner that containers from each mold in the forming machine occupy a given column or columns in the lehr. See U.S. Patent 4,004,904, which forms the basis for the prior art portions of claims 1, 7 and 9. This patent, however, discloses a system wherein identification of defective containers is made later in the process. This patent teaches a method of marking and disposing of said defective containers after the bottles have been annealed in the lehr. It has also been known to reject bottles at the hot end of the line prior to their entering an annealing lehr. The human operator sets a control switch which instructs the reject control as to which bottles are to be discarded by the rejector. See U.S. Patent 4,332,606. U.S. Patent 4,614,531 discloses a computer control system for operating a reject mechanism in a glassware forming machine as the glassware exits the mold section thereof. This system performs generally the same function as that disclosed in U.S. Patent 4,332,606 but employs different hardware. U.S. Patent 4,639,263 discloses a method for inspecting glassware during production and acquiring data therefrom. This patent discloses very limited inspection performed in every container produced. Reject devices are provided for eliminating defective products. U.S. Patent 2800226 also discloses a system for removing bottles from a conveyor line. It has also been known to have plant workers remove a container manually on a periodic basis for purposes of inspection. In spite of the previously known systems, there remains a real and substantial need for improved apparatus and an associated method for effecting, on a sampling basis, inspection of containers prior to entry thereof in an annealing lehr in an automated and efficient manner. It is an object of the present invention to provide apparatus and a method for the efficient sampling of containers to be inspected without affecting the smooth flow of the containers. According to one aspect of the invention there is provided apparatus for transporting and inspecting containers comprising an annealing lehr for cooling said containers, supply conveyor means having a section disposed adjacent to said annealing lehr for transporting said containers from a source of said containers to said annealing lehr, inspection means for inspecting at least some of said containers, stacker means disposed on the opposite side of said section of said conveyor means from said annealing lehr for transferring containers from said section of said conveyor means to said annealing lehr, said stacker means having a reciprocating pusher bar for contacting said containers and urging them toward said lehr characterised by means for selectively diverting containers supplied to said supply conveyor means to said inspection means before such containers are pushed into said lehr and by means for returning to said supply conveyor means or to said lehr containers so diverted which are determined, by said inspection means, to be acceptable. According to another aspect of the invention there is provided a method of transporting containers from a source of such containers to an annealing lehr and of inspecting selected said containers, including providing supply conveyor means extending from said source of containers and having a section disposed adjacent said annealing lehr, providing inspection means for inspecting at least some of said containers, providing stacker means disposed on the opposite side of said section of said conveyor means from said annealing lehr, said stacker means having a pusher bar for transferring containers from said section of said supply conveyor means to said annealing lehr, the method including transporting containers on said supply conveyor means from said source to said lehr, characterised in that periodically said stacker means is operated to cause said pusher bar means to transfer, to said lehr, less than all of said containers on said section disposed adjacent said lehr, whereby containers remaining on said section are selected for inspection and are passed by said conveyor means to inspection means where they are inspected and, if they pass inspection, are delivered to said lehr. According to a still further aspect of the invention there is provided a method of transporting containers from a source of such containers to an annealing lehr and of inspecting selected said containers, including providing supply conveyor means extending from said source of containers and having a section disposed adjacent said annealing lehr, providing inspection means for inspecting at least some of said containers, providing stacker means disposed on the opposite side of said section of said conveyor means from said annealing lehr, said stacker means having a pusher bar for transferring containers from said section of said supply conveyor means to said annealing lehr, the method including transporting containers on said supply conveyor means from said source to said lehr, characterised in that selected containers for inspection are diverted from said supply conveyor means upstream of said section adjacent the lehr, are passed to inspection means for said inspection and, if they pass inspection, are returned to said supply conveyor means upstream of said lehr. One embodiment of the invention provides a pusher bar having a plurality of gates which are adapted to be aligned with containers positioned on a primary conveyor. One or more gates may be opened so as to permit containers aligned with such open gates to remain on the conveyor and not to be urged by the pusher bar into the lehr. Opening of the gate results in a pusher bar urging the other containers into the lehr, but having the contained to be inspected pass through the open gate and then be transferred to inspection means. In an alternate embodiment, the pusher bar is of lesser width than the array of containers thereby permitting an end container to remain on the primary conveyor and be delivered to the inspection means. Control means are employed to coordinate operation of the pusher bar, the gates, the inspection means and the container forming machine and take-away conveyors which deliver newly formed containers from the forming machines to the primary conveyor. It will be appreciated that reference herein will be made to both a take-away conveyor and a primary conveyor which may be endless belt types of conveyors. If desired, a single conveyor may be employed for both purposes. The term supply conveyor means as used herein is intended to include an arrangement in which a take-away conveyor delivers the containers to a primary conveyor which carries the containers to the lehr and an arrangement in which a single conveyor receives the newly formed containers and carries them to the lehr. By effecting the inspection at the hot end of the lehr, more timely information regarding the nature of the containers being inspected may be obtained and may be used more quickly in subsequent production operations. Embodiments of the invention are described below by way of example, with reference to the accompanying drawings, wherein:- FIGURE 1 is a schematic plan view of a form of a prior art container manufacturing and inspecting system, FIGURE 2 is a plan schematic view of a portion of an apparatus embodying the present invention, FIGURE 3 is a plan view of the apparatus of Figure 2 in the middle of a cycle of operation, FIGURE 4 is a perspective view of a form of gate in an embodiment of the present invention, FIGURE 5 is a perspective view of another embodiment of the gate construction, FIGURE 6 is a perspective view of yet another form of gate, FIGURE 7 is a partially schematic plan view of an inspection system of the present invention, FIGURE 7A is a detail of a form of bottle delivery element shown in Figure 7, FIGURES 8 to 11 are plan views showing a cycle of operation of the inspection apparatus, FIGURE 12 is a plan view of a form of inspection apparatus embodying the present invention, FIGURE 13 is a plan view showing the inspection apparatus of the present invention operated in a different manner from that of Figure 12, FIGURE 14 is a plan view of a modified form of inspection apparatus embodying the present invention, FIGURE 14A is a detail of the gate position of Figure 14, FIGURE 15 is a top plan view of the apparatus of Figure 14 in a modified position, FIGURE 15A illustrates a detail of the open gate position of the apparatus of Figure 15, FIGURE 16 is a top plan view of a modified form of inspection system embodying the present invention, FIGURE 17 is a schematic plan view showing a modified form of stacker of the present invention, FIGURES 18 to 20 are partially schematic plan views showing a modified form of container receiving apparatus in various positions, and FIGURES 21 and 22 are schematic illustrations of control means suitable for use in the present invention. As used herein the term "container" or "containers" shall be deemed to include unfilled glass containers which may be at an elevated temperature as a result of their having been molded immediately prior to the processing taking place in this invention. Figure 1 shows a prior art form of apparatus for manufacturing and inspecting of glass containers on a sampling basis. Referring now more specifically to Figure 1, there is shown schematically a prior art system wherein glass containers are molded in molds contained in a forming machine 2 to emerge therefrom and are transported in the direction indicated by the arrows on take-away conveyor 4 which is operatively associated with cross or primary conveyor 6. The conveyor 6 is interposed between the stacker mechanism 8 and the annealing lehr 16. The take-away conveyor 4 and primary conveyor 6 together form supply conveyor means for carrying containers from the forming machine 2 to the entry end of the annealing lehr. The primary conveyor 6 thus provides a section of the supply conveyor means which is disposed adjacent to the entry end of the annealing lehr. In operation, a series of containers in single file will be positioned on the primary conveyor 6 adjacent to the lehr 16. Pusher bar 10 reciprocates in a direction generally perpendicular to the path of movement of the primary or cross conveyor 6. The pusher bar 10 is fixedly secured to a pair of guide rods 12,14 which are received within and are subjected to relative reciprocating movement with respect to stacker 8. Movement of the pusher bar 10 toward the annealing lehr 16 results in delivery of a row of the containers such as 22 into the annealing lehr. Four such rows, 22, 24, 26, 28 are shown in Figure 1. The annealing lehr has an entry hot end 18 and a discharge cold end 20 with the containers moving on an internal conveyor in the direction indicated by the arrow. Passage of the containers through the lehr 16 may take about twenty minutes, for example. At the exit of the lehr 16 is an accumulation area 30 over which the containers pass en route to the exit conveyor 32. The containers generally positioned in single file and relative spaced relationship move along conveyor 32 to on line continuous inspection conveyor 34 with sampling inspection being accomplished on containers emerging on conveyor 36. It will be appreciated that in general sampling inspection is performed for properties which are likely to be changing slowly over a period of time. Referring to Figure 2, features of the present invention will be considered in greater detail. A forming machine (not shown) or other source of containers, provides a supply of containers to take-away conveyor 50 which is operatively associated with a primary conveyor 52. The annealing lehr 54 has an entry hot end disposed adjacent to the primary conveyor 52 and an exit cold end (not shown) disposed remote therefrom. The take-away conveyor 50 and primary conveyor 52 again form successive sections of supply conveyor means for carrying containers from the forming machine to the entry end of the annealing lehr. The stacker 56 has a reciprocating pusher bar 58 which reciprocates in the direction indicated by the arrows. It is shown in Figure 2 in the retracted position. The pusher bar 58 in this embodiment has a plurality of gates 70-86 (even numbers only) each of which is rotatable about a vertical axis and each of which is of greater width than the diameter of the containers being transported on the primary conveyor 52. As a result, when a gate is opened, an aligned container may pass freely through the open gate. As shown in Figure 2, a series of spaced, single file containers which may be glass bottles, for example, 90-106 (even numbers only) are positioned generally centrally aligned with the gates 70-86. Shown in the lehr 54 are a series of rows 120, 124, 126 of containers which have been introduced into the entry hot end 130. If the pusher bar 58 shown in Figure 2 were moved toward the lehr 54 with all of the gates closed, all of the containers 90-106 would be moved into the lehr 54 to create an additional row of containers. Referring to Figure 3, it will be seen that the pusher bar 58 has been advanced to a position on the opposite side of primary conveyor 52 and has gate 78 in the open position with the remaining gates in the closed position. As a result, containers 90-96 and 100-106 have been introduced into the annealing lehr 54 to create a new row 140 of containers therein. As a result of gate 78 being in the open position, however, container 98 has remained on the primary conveyor 52 and will move to the right along with the conveyor. By appropriate control means to be disclosed hereinafter the selection of container 98 as being a specimen related to a particular mold in the forming machine and being the container to be inspected has been accomplished. The control means also effect the timing necessary to align container 98 with the gate 78 and open the gate thereby permitting separation of the container 98 to be inspected and subsequent delivery of the same to an inspection apparatus. It will be appreciated that this separation and inspection is accomplished prior to the container's entry into lehr 54. Referring to Figure 4 there is shown a pusher bar having a plurality of gates such as those shown in Figures 2 and 3 pivoted about vertical axes. The pusher bar is positioned adjacent to primary conveyor 52 and has gate 78 journalled between rail 152 and a lower rail (not shown). Rotation of gate 78 with shaft 150 causes the gate 78 to assume an open position and will permit passage of container 98 therethrough. Similarly, gates 76, 80 and 82 have shafts 154, 156, 158 as do the other gates which are not shown in this view. Rotation of such gates may readily be effected by any desired means such as air cylinders 160, 162, 164, 166 and their associated linkages 167, 168, 169, 170, respectively, for example. As is shown in Figure 5, a vertically slidable form of gate may be employed. Gate 172 is fixedly secured to shaft 173 and assumes the open position when the shaft is elevated. Similarly, gates 174 and 176 as well as additional gates are adapted to be slidable in a vertical direction with shafts 180 and 182 to thereby reciprocate between closed and open positions. Cylinders 177, 178, 179, may be employed for this purpose. In the embodiment shown in Figure 6 the gates rotate about a horizontally oriented axis. Gate 190 is fixedly secured to support 192 which in turn is hinge-mounted to rail member 194. Similarly, gates 198 and 200 are secured respectively to supports 196, 202. These gates may be operated by air cylinders 202, 203, 204 and their respective linkages 205, 206, 207. It will be obvious to those skilled in the art that numerous means for effecting movement of the gates between open and closed positions responsive to signals from the control means may be provided. For example, air valves and cylinders or rotary solenoids may be employed to (a) rotate shafts 150, 154, 156, 158 of Figure 4, or (b) reciprocate shafts 173, 180, 182 of Figure 5, or (c) rotate supports 192, 196, 202 with respect to rail member 194 of Figure 6. It will be appreciated that other forms of movement of individual gates of the plurality so as to permit a single predetermined container to pass through the pusher bar and be isolated for inspection may be employed. As is shown in Figure 7, the primary conveyor 52 has a container 210 positioned thereon. This container was isolated for inspection purposes by the procedure described hereinbefore in connection with the description of Figures 2 and 3. In this embodiment the primary conveyor 52 is extended to provide additionally a means for delivering container 210 to the hot end inspection equipment 214. It will be appreciated that the inspection equipment 214 may be of any desired conventional or unconventional variety as the present invention centers around delivery of the containers to the inspection equipment and return therefrom, but not on what particular properties are being inspected and what means are used to effect the inspection. As has been indicated, in general, inspection of this type involves sampling to monitor properties which are relatively slow to change such as container thickness, height or diameter as well as weight and volume. The portion of primary conveyor 52 identified generally by the number 216 may be considered as an inspection delivery conveyor. After inspection, if the container has been rejected, it will emerge from the inspection apparatus 214 on conveyor 220 to be discarded. If the container has passed the inspection test, it will be returned to the lehr 54 by the return conveyor 222. A container 224 which has passed inspection is shown on return conveyor 222 positioned between two sensors 230, 232 which confirm the presence of a container awaiting entry into the lehr 54. Referring to Figure 7A details of a preferred means of delivering the container 224 into the righthand-most portion of lehr 54 aligned with the corresponding containers of the other row will be considered. When the control means delivers a signal to initiate action of the delivery member 240, arm 242 rotates in a counterclockwise direction until it contacts the righthand-most surface of container 224. It is then pushed into the lehr 54 by cylinder 245 which extends and moves container 224 in the direction of the lehr 54. The arm 242 is fixedly secured to a shaft 244 which is connected to rotary solenoid 246 which in turn is fixedly secured to connecting rod 247 of cylinder 245 and is actuated by the control means signal. In the form shown, solenoid 246 and cylinder 245 are secured to mounting plate 249. After completion of delivery of container 224, the arm 242 is returned to the position shown in Figure 7. A cycle of operation of this system is illustrated in Figures 8 through 11 with segment 216 of primary conveyor 52 serving to deliver a container 210 to inspection apparatus 214. It will be appreciated that the segment 216 of conveyor 52 may be provided as a separate conveyor operatively associated with primary conveyor 52. For simplicity of reference herein, both concepts will be embraced by referring to the primary conveyor as being the conveyor which delivers containers to the pusher bar 58 and the delivery containr 216 being referred to as a portion of the inspection means regardless of whether it is a portion of primary conveyor 52 or a separate conveyor. In Figure 8 the container 210 has entered delivery conveyor 216 and is moving toward the inspection apparatus 214. In Figure 9 it is about to enter the inspection apparatus 214. Figure 10 shows schematically passage of the container through the inspection apparatus and emerging on conveyor 222 as it has passed the inspection. When the container 210 is between the sensors 230, 232 and the control means (not shown) actuates the delivery means 240 and arm 242 rotates so as to contact the container and introduce it into lehr 54 in the direction indicated by arrow 244. Figure 12 illustrates a first mode of operation of the invention in respect of lehr positioning of the containers. In the embodiment of Figure 12, the lane 250 of the internal conveyor of lehr 54 has been established such that none of the uninspected containers will move in that lane 250. To the left of lane 250 are a plurality of rows of containers 252, 254, 256, 258, 260 of containers bearing the label "U" to indicate that they have not been inspected. Containers 262, 264, 266 which are in lane 250 have been returned to the lehr 54 from delivery conveyor 222 of inspection means. These containers bear the legend "I". In this type of arrangement as lane 250 is reserved for containers which have passed inspection, there is no need to get into detailed coordination of timing of the re-entry of the inspected containers into the lehr 54. On the other hand, the number of containers which can be processed by lehr 54 is reduced to the extent of the loss of the use of lane 250 except for inspected containers. Referring to Figure 13, this embodiment shows a lane 280 which is adapted to both function to transport inspected containers 282, 286 and uninspected containers 284, 288. In operating this type of system, when it is desired to sample inspect a particular container, the proper one of the gates of the pusher bar will be opened so that forward movement of the pusher bar 58 will result in the container to be inspected not being introduced into the lehr 54 at that time. Reject conveyor 215 will be employed to remove containers which do not pass inspection. In employing this type of arrangement, the control means must coordinate the opening of the proper gate in the pusher bar 58. The control means must also signal the actuator for the pusher bar 58 to leave a space in lane 280. In general, this will be accomplished most readily by having sensors 230, 232 sense the presence of a container therebetween, actuating the pusher bar 58 before an uninspected container is aligned with lane 280 and as the pusher bar 58 urges the nine uninspected containers for delivery into the lehr 54 having the delivery mechanism 240 deliver the inspected container such as 282 into lane 280 in the gap. It will be appreciated that the control means has information regarding which particular mold in the forming machine 2 has produced a specific container and that a determination will be made as to when a given sampling will be made and as to which mold the sample will be taken from. For example, referring once again to Figures 12 and 13, the sample to be introduced into the inspection apparatus 214 will be determined based upon timing since the correspondence between the container from a given mold and a particular gate of the stacker bar 58 is known. In the case of Figure 12, the pusher bar 58 will be shortened as it is not desired to have any but inspected containers in lane 250. In the alternative shown in Figure 13, sampling is effected in the same fashion, the difference being that if it is desired to return an inspected container 282 to the lehr 54, the pusher bar 58 is actuated when the forward-most container is aligned with the gate upstream from gate 292. Referring to Figure 14 an alternate arrangement is illustrated. In this arrangement a container selector means 300 is positioned adjacent to take-away conveyor 302 which is operatively associated with primary conveyor 306 adjacent to which are positioned pusher bar 310 and annealing lehr 312. The sample delivery conveyor 308 is disposed adjacent to take-away conveyor 302. The container selector means 300 transfers a predetermined container desired to be inspected from conveyor 302 to conveyor 308. This mechanism may be any conventional mechanism of this type which may determine selection by timing or other means. The selected container passes into the hot end inspection area equipment 316 and is inspected. If the container does not pass inspection, it is discarded through conveyor 318. If it does pass inspection, return conveyor 314 delivers the same to lehr 312 by means of delivery mechanism 320 which may be identical to delivery means 240 (Figure 13). Sensors 322, 324 detect the presence of a container on return conveyor means 314 adjacent to the lehr 312. In this embodiment as is shown in Figures 14 and 14A, the pusher bar has a gate 328 disposed closest to the inspection equipment 316. When it is desired to employ lane 330 for both uninspected and inspected containers, the gate 328 may be closed as is shown in Figure 14A to deliver a full array of uninspected containers to the lehr 312. Alternately, gate 328 may be opened. Then container 329 remains on conveyor 306, thereby creating a gap in lane 330 which may be filled by a container emerging from return conveyor 314. This concept is illustrated in Figures 15 and 15A wherein the pusher bar 310 has been advanced while the gate 328 open and a void 336 being present in the lehr. Container 340 which is adjacent to open gate 328 will be the first container or lead container in the next array which is introduced into the lehr 312. It will be appreciated that the control means will signal the pusher bar 310 to initiate the next cycle earlier than normal. Referring to the embodiment shown in Figure 16 wherein a stacker 360 cooperates with a primary conveyor 364 and a lehr 366. The primary conveyor 364 again forms a section, adjacent the entry end of the lehr, of a supply conveyor means for conveying containers to the lehr. This supply conveyor means again includes a take-away conveyor 362 for carrying the containers to the primary conveyor 364. In this embodiment a container selector at 374 transfers a container to be inspected from take-away conveyor 362 to delivery conveyor 376 of inspection means 380. Container 378 is shown as having been selected for this purpose and as being transported by delivery conveyor 376 to inspection means 380. Rejected containers are removed from the system on conveyor 382. Successfully inspected containers such as 388 are delivered by return conveyor 390 to take-away conveyor 362 (or primary conveyor 364) by means of second container selector 392. Sensors 394, 396 determine the presence of a successfully inspected container 388 which will be returned to take-away conveyor 362 by container selector 392. If desired, this same approach may be employed to return an inspected conveyor to the primary conveyor 364. Referring to Figures 17 through 20 another embodiment of the invention will be considered. In this embodiment, a lehr 400 receives containers from a primary conveyor 402 as a result of reciprocating movement of pusher bar 404 (shown schematically). When a container has been isolated for inspection by the motion of the gated pusher bar, it continues down the primary conveyor 402 into container selector 410. It is then delivered to the inspection area and returned to a lane in the lehr reserved for inspection containers. It will be appreciated that the pusher bar 404 is of width W P which is less than the width W L of the lehr. This avoids interference between pusher bar 404 and container selector 410 within which container 408 is positioned in Figure 17. As is shown in Figure 18, the container receiver has a generally U-shaped portion having a base wall 420, a first lateral wall 422 which is pivoted about a vertical axis 424 and is adapted to move between position shown in solid in Figure 18 and the dotted position 422′. Similarly, second lateral wall 426 is pivoted about a vertical axis 428 and is adapted to assume rotated position 426′. Fixedly secured to base wall 420 is a connector rod 430 to which is secured an actuator rod 432 which is secured to a suitable form of power (not shown) such as a hydraulic or pneumatic cylinder, for example, which will effect reciprocation of connecting rod 430 in the directions indicated by the arrows responsive to control means action. The primary conveyor 402, as shown in Figure 19 delivers bottle 408 to delivery conveyor 412 of the inspection means by having first lateral wall 422 rotated 90 degrees to the position shown in 422′ and having second lateral wall 426 in a position perpendicular to base wall 420. With the channel defining walls 420, 422, 426 in this position, connecting rod 430 is moved in the direction indicated by the arrow, i.e. toward the top of the page to deliver the container 408 to conveyor 412. In the dotted position shown in Figure 19, container 408′ has been delivered to conveyor 412 and second lateral wall 422 is in position 422′. After inspection has been completed, as is shown in Figure 20, delivery conveyor 412 is reversed to return the container which has been inspected successfully to primary conveyor 402. When the returning container 408 reaches position on the delivery conveyor 412 shown in Figure 20, conveyor 412 stops and the control means activates container selector 410. The first lateral wall moves to position 422 and the second lateral member 426 moves to the position shown in Figure 20. Cylinder 433 retracts in the direction of the arrow moving the container across the primary conveyor 402 and into the lehr 400. In this manner the inspected container is introduced into the lehr 400. Second lateral wall 426 is then returned to the position shown in Figure 18 in order to initiate the next cycle of operation. Any suitable means for effecting rotational movement of lateral walls 422, 426 such as hydraulic or pneumatic actuators, for example, may be employed and are well known to those skilled in the art. It will be appreciated that the method of the present invention may advantageously be employed in the hereinbefore disclosed apparatus. A series of containers are transported on a primary conveyor, such as 52 of Figure 7 or 402 of Figure 17, which moves containers to a position between a pusher bar such as 58 of Figure 7 or 404 of Figure 17, and a lehr, such as 54 or 400 of Figures 7 or 17, respectively. The pusher bar actuates when a single file array of spaced containers is in front of the pusher bar. The pusher bar 58, 404 is then employed to transfer less than all of the containers to the lehr. The container not transferred to the lehr is delivered to inspection means wherein the inspection is effected. In one embodiment of the method the pusher bar is provided with a series of gates of sufficient size to permit passage of a said container therethrough such as in the case of pusher bar 58. In another embodiment, the pusher bar is of reduced relative width with respect to the width of the array of containers. In each case, movement of the pusher bar toward the lehr serves to retain on the primary conveyor the predetermined container to be inspected. After inspection, containers which have been passed are returned to the lehr or conveyor means for introduction into the lehr. In general, it will be advantageous to employ the method with a forming machine containing molds wherein containers are formed such that the inspection may be effected at the hot end of the lehr. Control means are provided to coordinate operation of the conveyor means, the pusher bar, the lehr and the inspection means. The inspection means will generally be provided with conveyor means to deliver the container from the primary conveyor to the inspection equipment and conveyor means to return containers which pass inspection to either the take-away conveyor means, the primary conveyor or the lehr directly. Referring to Figure 21 there is shown schematically a form of control means which may be employed in a system of the invention such as that illustrated in Figure 13. A series of signals 500, 502 and 520 which correspond in number to the number of mold sets in the forming machine are provided. Signal 500 corresponds to section 1 of the take-out conveyor disposed adjacent to the first mold set, signal 502 corresponds to section 2 of the take-out conveyor and signal 520 corresponds to section m of the take-out conveyor corresponding to mold set m (not shown). It will be appreciated that the number of signals 500, 502, 520 will correspond with the number of mold sets with one such signal being provided for each such mold set. Tracking blocks 524, 526, 530 receive signals, respectively, from their respective sections of the take-out conveyor. In addition, in the form illustrated, each tracking block 524, 526, 530 receives three additional signals. A signal from the forming machine (not shown) occurs when a container from a particular mold set within a particular section is moved onto the take-away conveyor. For example, when a container from section 1 is set on the take-away conveyor, a signal is emitted over line 500 and to tracking block 524. These signals may either be present in the control portion of the forming machine or can be furnished by any conventional or other desired sensor means positioned near the means used by the forming machine to introduce containers onto the take-away conveyor. A sensor on the lehr stacker 56 (Figure 13) is emitted just as the pusher bar 58 is about to begin its forward motion to move a group of containers from the primary conveyor into lehr 54. This signal is furnished over line 536 to tracking block 524 by line 540, to tracking block 526 by line 542 and to tracking block 530 by line 546. It will be appreciated that regardless of how many tracking blocks are present, each will receive a signal from the sensor on the stacker drive. An incremental encoder (not shown) which outputs a pulse for a given amount of motion of the take-away and primary conveyors has its output signals introduced into counter 560. The encoder tracks the motion of the conveyors and may preferably be a contacting wheel which rides on the conveyor top. As a result, the encoder's output is an accurate measure of the motion of the conveyors and the containers moving on the conveyor. The output of counter 560 is introduced into each tracking block 524, 526, 530 over line 562 through connections 564, 566, 568, respectively. Shown in the upper portion of Figure 21 is a computer 570 which has a keyboard input 572 for entry and a display 574 for presenting human-readable output. The fourth signal introduced into the tracking blocks 524, 526, 530 is emitted from computer on line 580 and is respectively introduced into tracking blocks 524, 526, 530 over lines 582, 584 and 586. This fourth signal enables one and only one of the tracking blocks depending on which section of the forming machine is producing the container desired to be inspected. The computer may be programmed in any suitable manner readily known to those skilled in the art. A signal from the computer 570 tells one of the tracking blocks 524, 526, 530 that it is to select a container. The computer preferably has a look-up table to convert the mold number which has been input by an operator to the section number of the forming machine where that mold number is being manufactured. The computer may also preferably include a timer and programming to select automatically one container from each section at a predetermined time interval. As has been indicated hereinbefore, it is preferred that a tracking block such as 524, 526, 530 be provided for each section of the forming machine corresponding to each mold set. The tracking blocks 524 526, 530 store the count received from encoder counter 560 which is emitted by the counter 560 instantaneously with receipt of the signal from the take-out. This number will be considered as being N a . The tracking block also contains the expected number of counts between a container being received on the take-out conveyor and it arriving at a particular gate on the pusher bar. These numbers will be considered as N₁, N₂ and N m , for purposes of discussion. When the tracking block receives a signal from the sensor on the stacker drive by way of line 536, it stores the value in the encoder counter. This number will be considered as N b . By determining N b -N a and comparing this number with the numbers N 1 , N₂, N m , the tracking block determines whether it finds a match within a small predetermined tolerance. If it does find a match it activates an output which represents the fact that a container made in its particular section which, for example, in tracking block 524 would be section 1 of the forming machine, is at a particular gate. If no match is found, no output is activated. If more than one match is found, the block chooses one of them and ignores the others. It will generally be preferred to provide each tracking block with as many outputs as there are gates on the stacker pusher bar. The outputs of the tracking blocks 524, 526, 530 are, respectively, operatively associated with OR gates 600, 602, 604. Each OR gate 600, 602, 604 is connected to gate drivers 610, 612, 614, respectively, by lines 616, 618, 620, respectively. The outputs of the OR gates activate the drivers 610, 612, 614 in order to activate the gate operating means such as an air valve or rotary solenoid in order to move the appropriate pusher bar gate thereby leaving the desired container on the primary container. It will be appreciated that there is an OR gate 600, 602, 604 for each gate in the pusher bar which is adapted to be operated by a driver 610, 612, 614 and that output signals from each tracking block 524, 526, 530 is introduced into each OR gate 600, 602, 604. For example, tracking block 524 provides signals to OR gates 600 on line 640 to OR gate 602 on line 642 and on line 644 to OR gate 604. The lines connecting tracking block 526 to OR gates 600, 602, 604 are, respectively, 650, 652, 654. Tracking block 530 is connected to OR gate 600, 602, 604, respectively, by lines 658, 660 and 662. Each of the OR gates receive signals indicating when a desired container is in front of its associated gate. It will be appreciated that there are as many OR gates as there are gates in the pusher bar. Each OR gate has as many inputs as there are sections in the forming machine. Referring to Figures 13 and 22, a preferred approach to providing control means for return of an acceptable inspected container to the primary conveyor or lehr will be considered. Signals from sensors 230, 232 (Figure 13) which detect the presence of a bottle on return conveyor 222 are by line 700 introduced into control block 702. When the presence of a container is sensed and a signal is received by control block 702 the control block 702 emits a signal over line 704 to conveyor motor drive 706 in order to stop conveyor 222. It also emits a signal over line 710 instructing the drive for the stacker motor 712 to initiate a cycle earlier than normal. In the instance shown in Figure 13, the cycle begins when only nine containers are on the primary conveyor 52 in front of the pusher bar 58 instead of the usual ten. This leaves an empty space in the righthand-most lane of the lehr 54. After a suitable delay following movement of the pusher bar 58 with nine containers on the primary conveyor, the empty space created by the use of nine containers will be positioned in a location opposite conveyor 222. The control block 702 provides a signal over line 718 to driver 720 which activates rotary solenoid 246 (Figure 7A) to move the arm 242 of delivery means 240 to a position behind the container which is positioned on the return conveyor 222. When the arm is in place, the control block 702 emits a signal over line 724 to activate an air valve through an appropriate driver thereby causing the cylinder 245 to extend moving the container into the empty space on the lehr conveyor belt. The cylinder is then retracted and the return conveyor is restarted. The stacker drive is returned to normal operation and pushes ten containers into the lehr on each cycle. It will generally be desirable to provide display means which either record or display the results of an inspection of a container in order to permit an operator to make adjustments to the forming machine or to make other adjustments responsive to unsuccessful inspection reports. If desired, the system may be automated and function as a servomechanism wherein defects found in the sample containers which have been inspected result in automated adjustment to the container forming machine. It will be appreciated that depending upon the frequency with which a particular property is likely to change, the sampling times for inspection may be varied as desired. In general, the sampling times may be in the order of about 1 to 60 minutes between samples of containers taken from the same mold with respect to glass containers. It will be appreciated that one of the advantages of the invention is that feedback of information regarding defects is obtained more promptly as inspection is effected at the hot end of the lehr rather than waiting the significant period of time which may be on the order of twenty minutes, for example, to inspect the containers at the cold end of the lehr. It will be appreciated that the present invention provides an effective means for isolating predetermined containers for inspection at the hot end in an efficient manner. It will further be appreciated that the apparatus and method of the present invention effects this removal of predetermined containers to be inspected in a manner which permits effective monitoring of all molds which are producing containers, effects timely inspection and permits easy withdrawal of the container to be inspected and return of the same if inspection is satisfactory. All of this may be accomplished while either reserving a specific lane of the lehr for return of successfully inspected containers or, in the alternative, coordinating return of successfully inspected containers to a lane which also carries uninspected containers. As has been indicated hereinbefore, the inspection equipment may take the form of any conventional or unconventional equipment designed to inspect for desired properties in a particular container and forms no part of the invention. Characteristics for which inspection might be desired are container wall thickness, container outer and inner dimensions, container symmetry, container weight and container volume. If desired, mold symbols may be placed on the containers in the molding operation as a means for facilitating identification of the particular mold from which a container emerged. In a preferred practice of the invention, the control means will permit determination of the mold from which a container originated based upon position on the conveyor means without requiring or using mold symbols. Whereas particular embodiments of the invention have been described above for purposes of illustration, it will be evident to those skilled in the art, that numerous variations of the details may be made without departing from the invention as defined in the appended claims. It will be noted that in the method and apparatus described with reference to the drawings, sampling inspection of the containers takes place before the containers to be inspected have entered the lehr. Furthermore, the inspection results are made available in a timely manner so as to enhance efficiency of production. The method and apparatus described with reference to the drawings affords these advantages in a simple and economical manner which is compatible with other systems for production and inspection of containers.

Claims: Apparatus for transporting and inspecting containers (90-106) comprising an annealing lehr (54, 312, 366, 400) for cooling said containers, supply conveyor means (52, 306, 264) having a section disposed adjacent to said annealing lehr (54, 312, 366, 400) for transporting said containers from a source of said containers to said annealing lehr (54, 312, 366, 400), inspection means (214, 316) for inspecting at least some of said containers, stacker means (56, 360) disposed on the opposite side of said section of said conveyor means (52, 306, 364) from said annealing lehr (154, 312, 366, 400) for transferring containers (90-106) from said section of said conveyor means (52, 306, 364) to said annealing lehr, said stacker means (56, 360) having a reciprocating pusher bar (58) for contacting said containers (90-106) and urging them toward said lehr (54, 312, 366, 400) characterised by means (70-86; 216) for selectively diverting containers supplied to said supply conveyor means to said inspection means (214, 316) before such containers are pushed into said lehr and by means (222, 314) for returning to said supply conveyor means or to said lehr (54, 312, 366, 400) containers so diverted which are determined, by said inspection means (214, 316), to be acceptable. Apparatus according to claim 1, characterised in that said pusher bar (58) has means (70-86) for delivering less than the total number of said containers (90-106) on said section of said conveyor means (52, 306, 364) to said annealing lehr (54, 312, 366, 400), whereby predetermined containers may be delivered to said inspection means (214, 316) for inspection. The apparatus of claim 1, including means (376), upstream of said section (364) of said supply conveyor means (362, 364) adjacent said lehr (366) for diverting selected containers from said supply conveyor means to said inspection means (380) and for returning (390) said containers, if they pass inspection, to said supply conveyor means (362, 364) upstream of said lehr (366). The apparatus of claim 2 wherein said pusher bar means (58) is mounted for reciprocation in a path generally perpendicular to the path of movement of said section of said conveyor means (52, 306, 364), and said pusher bar (58) has gate means (70-86) for permitting a container aligned therewith to remain on said section of said supply conveyor means (52, 306, 364) while the remainder of said containers are transferred to said annealing lehr (54, 312, 366, 400). The apparatus of claim 4 including control means (570) for timing the opening of said gates (70-86) when they are aligned with said containers (90-106) whereby opening a said gate will permit passage of a container therethrough when said pusher bar (58) delivers the remaining containers to said annealing lehr (54, 312, 366, 400). The apparatus of claim 3 wherein said gate means (70-86) has a plurality of gates which when open will permit a container to pass therethrough, whereby the container passing through said gate will not be moved with the other containers being moved by said pusher bar (58). A method of transporting containers (90-106) from a source of such containers to an annealing lehr (54, 312, 366, 400) and of inspecting selected said containers, including providing supply conveyor means (52, 306, 264) extending from said source of containers and having a section disposed adjacent said annealing lehr (54, 312, 366, 400), providing inspection means (214, 316, 380) for inspecting at least some of said containers, providing stacker means (56, 360) disposed on the opposite side of said section of said conveyor means from said annealing lehr, said stacker means having a pusher bar (58, 310) for transferring containers from said section of said supply conveyor means to said annealing lehr, the method including transporting containers on said supply conveyor means (52, 306, 264) from said source to said lehr, characterised in that periodically said stacker means (58, 360) is operated to cause said pusher bar (58, 310) to transfer, to said lehr, less than all of said containers on said section disposed adjacent said lehr, whereby containers remaining on said section are selected for inspection and are passed by said conveyor means to the inspection means (214, 316, 380) where they are inspected and, if they pass inspection, are delivered to said lehr. The method of claim 7 including providing said pusher bar means (58) with a series of gates (70-86) of sufficient size to permit passage of a said container therethrough, opening a said gate (70-86), aligning a desired container to be inspected with said gate, moving said pusher bar (58) to engage and transfer all said containers except said desired container which desired container passes through said open gate, and delivering said desired container to said inspection means (214, 316). A method of transporting containers (90-106) from a source of such containers to an annealing lehr (366) and of inspecting selected said containers, including providing supply conveyor means (362, 364) extending from said source of containers and having a section disposed adjacent said annealing lehr, providing inspection means (380) for inspecting at least some of said containers, providing stacker means (360) disposed on the opposite side of said section of said conveyor means from said annealing lehr, said stacker means having a pusher bar (58) for transferring containers from said section of said supply conveyor means to said annealing lehr, the method including transporting containers on said supply conveyor means (362, 364) from said source to said lehr, characterised in that selected containers for inspection are diverted from said supply conveyor means (362, 364) upstream of said section adjacent the lehr, are passed to said inspection means (380) for said inspection and, if they pass inspection, are returned to said supply conveyor means upstream of said lehr. The method of claim 7 or claim 9 including employing said method to inspect glass containers (90-106), said annealing lehr (54, 312, 366, 400) having an entry hot end (18, 130).

Inventors: MAXSON RICHARD N, RUGABER DAVID A, MAXSON, RICHARD N., RUGABER, DAVID A.
Applicants: AMERICAN GLASS RES, AGR INTERNATIONAL, INC.
Application year: 1988
Main classification: C03B35
IPC codes: B65G47, B07C5, C03B35, G01B21