GB2156792A - Closure cap feeds - Google Patents

Abstract

A cap pickup (1) for use with straight line sealing machines (2) which seal containers (5) with closure caps (7) has a simplified construction including a central mounting frame (36) on which several cap applying shoes (23, 27) with a cap turning wiper (25, 26) on each shoe are movably mounted and has a cap contacting member positioned centrally of a cap chute end (6) and above cap tracks (10) on the cap chute and positioned in combination with the cap tracks to hold the endmost cap with its forwardmost cap skirt portion positioned to engage containers on the container finish (18) above the uppermost portions of the container cap threads or lug members. <IMAGE>

Description

SPECIFICATION Improvements relating to closure cap feeds The present invention relates to container sealing machines and more particularly to an improved cap pickup or cap applicator for use in straight line sealing machines for the initial application of closure caps to containers being moved through the machine and beneath the cap pickup.

Straight line sealing machines are in common use for sealing glass and other containers with threaded or lugged caps. In these sealing machines, containers are passed through at extremely high speeds as caps are fed from a cap supply hopper onto the moving containers. The cap feeding means includes an inclined chute and cap pickup which directs the caps onto the mouths of the moving containers while correctly positioning the caps and lightly twisting them onto the container threads or lugs.

In order to improve the efficiency and minimize the cost of container sealing operations, straight line sealing machines are being manufactured which run at ever increasing speeds so that sealing speeds have increased from several hundred containers per minute up to speeds in excess of 1,000 containers per minute. prior cap applicators are known and have been in use for some years. Such prior cap pickups include, for example, those illustrated in United States patents Nos.

3,280,534; 3,874,147; 3,977,161 and 4,199,914.

The cap pickup of the present invention includes a number of related and cooperating features which permit high speed cap application and at the same time provides a cap pickup which is easier to manufacture and which has increased reliability. In particular, the cap pickup of the present invention provides improved cap handling in the initial feed of the caps from the lower end of the cap feed chute onto the tops of the moving containers.

According to the present invention, a cap feed pickup comprises a cap feeding chute end having cap supporting tracks on the cap chute end, a plurality of cap levelling shoes with a cap turning wiper on each shoe, and a cap cover contacting member positioned centrally of the cap chute end and above said cap tracks and positioned in combination with the said cap tracks to hold the endmost cap in an inclined position in the cap chute end with its forward most cap skirt portion positioned to engage containers on the container finish above the uppermost portions of the container cap engaging thread or lug members.

A cap feed pickup constructed in accordance with the invention is capable of applying closure caps to closely spaced containers having relatively large container finish tolerances and moving at high speeds. Moreover, cap reversing means and magnets previously used for cap application can usually be dispensed with. The pickup may be constructed in such a way as to have improved visibility for the operator and improved steam distribution.

The invention may be carried into practice in various ways but two cap pickups embodying the invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 is an elevational view of the first cap pickup; Figure 2 is a top plan view of the cap pickup of Figure 1; Figure 3 is a vertical, sectional view taken along line 3-3 on Figure 2; Figure 4 is a top plan view partially cut away; Figures 5 and 6 are vertical sectional views taken along the lines 5-5 and 6-6 on Figures 1 and 3 respectively; Figure 7 is an elevational view of the second cap pickup; and Figure 8 is a top plan view of the pickup of Figure 7.

The cap pickup will first be described generally with particular reference to Figures 1 and 2. The cap pickup 1 is mounted on a straight line sealing machine 2 by means of a bracket 3. The sealing machine 2 has a continuously moving conveyor 4 whose top horizontal run carries a succession of containers 5 continuously beneath the pickup 1. Figure 1, for example, illustrates the conveyor 4 moving from left to right carrying a line of closely spaced containers 5 under a cap chute end 6.

Each container 5 engages a closure cap 7 positioned within the cap chute end 6 and carries the cap 7 forwardly beneath resiliently mounted cap applying shoes 8 and 9.

The closure caps 7 being fed towards the cap applicator from a cap feeding hopper (not shown) slide down an inclined cap feeding chute which terminates at the chute end 6.

The chute end 6 is best illustrated in Figures 1 to 3. The chute end 6 comprises spaced side rails 10 mounted for lateral adjustment on a chute end mounting bracket 11. As illustrated in Figure 3, the lateral spacing of the side rails 10 is provided for by mounting both rails 10 on the opposite ends of an adjusting screw 1 2. The screw 1 2 is threadedly coupled to each side rail 10 and is rotatably contained in the centrally positioned top shoe 1 3. Elongated adjustment slots 14 in a wing-like section 1 5 of the bracket 11 slidably contain rectangular guides 1 5 on the side rails 10 to hold them parallel during adjustment.Each of the side rails 10 has cap supporting cap track plates 1 6 on their bottom which engage opposite sides of the cap 7 skirt while permitting the moving containers 5 to pass beneath the endmost cap 7 in the chute end 6. As best illustrated in Figure 3, a moving container 5 engages the skirt 1 7 of a cap 7 centrally of the chute end 6 to pull the cap 7 from the chute end 6 and forwardly under the cap applicator 1. As will be described more fully below, the applicator 1 levels the closure caps 7 on the glass finishes 1 8 of the containers 5 while rotating the caps 7 to spin them downwardly into light sealing engagement with the moving containers 5.

In order to provide for a smooth and accurate feeding of each cap 7 from the chute end 6, the end most cap 7 in the chute end is precisely positioned with respect to the container finish 18. Thus, as illustrated in Figures 1 and 3, the forward and lowermost edge of the cap skirt 1 7 is positioned to engage a container 7 at its rim above the threads or lugs 1 9 on the container finish 1 8. This permits the cap 7 to be drawn out of the chute end without causing an objectionable interlock between the cap lugs and the container threads 1 9. The exact positioning of this endmost closure cap 7 is controlled by the use of the elongated and precisely dimensioned and positioned cap track plates 1 6.

Cap retaining buttons 20 mounted on leaf springs 21 hold the lowermost cap 7 in the chute end 6 at its container engaging position. A shim 22 is removably mounted on the chute end top shoe 1 3 and the shim 22 is proportioned so that the particular cap size being fed will have only an extremely small clearance, such as about .02 inches (0.51 mm) from the cap 7 cover and so that the cap slides freely and does not drag objectionable as i; is -tilled past the shim 22 and buttons 20. Ths cap 7 passes from its position beneath the shim 22 and a front shoe 23 while being held level by the ends of the track plates 16.The lead-in surface 24 of the shoe 23 (Figure 3) is rounded and dimensioned to cause the cap 7 to proceed under the shoe 23 while still level on the cap track plates with a light and levelling pressure being applied to the caps 7 by the front shoe 23.

Thus, during initial movement of the closure cap 7 from the chute end 6 and under the front shoe 23, the cap 7 is positioned horizontally on the cap track plates 1 6 and beneath the lower surface 24 of the front shoe 23 and in telescoping relationship with the container finish 1 8 above the container lugs or threads 19. In this position the cap 7 is stabilized and ready to turn evenly downwardly onto the container finish 1 8 as the moving container 7 carries the cap 7 under a first turndown drag 25 on the front shoe 23 and thereafter beneath a second turndown drag 26 on a rear shoe 27.

The front shoe 23 has a slightly inclined attitude to facilitate the above described downward cap movement while the rear shoe 27 has a generally horizontal position. These positions of the front and rear shoes 23 and 27 are maintained by resilient shoe mountings. Each of the shoes is mounted on a pair of spring loaded support rods 28 and 29 pivotally attached at 30 and 31 to the front and rear ends of the shoes 23 and 27 and slideably mounted under the force of compressed coil springs 32 and 33 within bearings 34 and 35 formed on a centrally positioned frame 36. The lowermost position of each of the shoes is determined by the pin held stops 37 and 38 attached to the top of each of the support rods 28 and 29 and spacer rings 39 and 40.The forward end 41 of the rear shoe 27 preferably includes a projecting ledge 42 to ensure that the rear shoe 27 remains above or level with the front shoe 23 thereby assuring a smooth passage of each closure cap 7 from the front shoe 23 to the rear shoe 27 as the cap 7 is carried along by a moving container 5.

In order to provide for a smooth feed of the caps into and out of the chute end 6, the chute end is mounted for rotation about a generally vertical pin 43 and a generally horizontally positioned pin 44 so that the chute end is free to swing upwardly if necessary against the force of a coil spring 45 positioned on a chute end positioning bolt 46.

Figures 7 and 8 illustrate a modification to the cap pickup shown in the preceding Figures. This embodiment has an extended rear shoe 50 for providing additional levelling action on the moving closure caps 7. Additionally, an additional hold down arm 51 is mounted on the rear end of the cap pickup frame 52. The arm 51 includes a hold down drag 53 which extends from the rearward end of the extended rear shoe 50 to the entrance end of the main sealing machine sealing head 54. This additional hold down drag 53 assures a tight initial cap application and more importantly prevents the applied caps 7 from backing off the containers 5 before the caps 7 are engaged by the sealing means such as the laterally spaced stationary shoe 55 and moving sealing belt 56. A compressed spring 57 on the mounting bracket for the additional hold down arm 51 and drag 53 permits the arm 51 to rise in the event there has been an improper cap application resulting in a cocked or damaged closure cap 7.

Reverting now to the cap pickup shown in Figures 1 to 6, and with particular reference to Figure 1, the presence of a cocked or damaged cap 7 is detected by the use of a spring mounted cocked cap detector arm 58 pivotally attached at 59 at the rear end of the support frame 36. This arm 58 operates a suitable switch (not shown) to activate an alarm or turnoff means as desired when a cocked or other improperly applied cap engages the detector arm.

Figure 4 illustrates a cap 7 in the containerengaging position in the cap chute end 6 with the closure cap being releasably held between the spaced track plates 1 6 and the shim 22 by the resiliently mounted cap engaging buttons 20. The middle cap 7 in Figure 4 illustrates the initial turning action applied to the moving closure cap 7 by the holddown drag or wiper 25 on the front shoe 23. The cap at the right of Figure 4 is in the final application position with the cap 7 being turned to a finger tight position on the container 5 through the intermediation of the holddown drag or wiper 26 on the rear shoe 27.

The vertical position of the lower end of the cap chute end 6 is determined by a removable shim 62 best illustrated in Figure 3. The shim 62 determines the limit of the clock-wise rotation (Figure 3) of the chute end 6 about its mounting pin 44 as a fixed surface 63 on the chute end 6 engages the upper surface of the shim 62. The shim 62 may be replaced as necessary should the lowermost position of the chute end require adjustment.

A slightly inclined plate member 64 is positioned on the lower surface of the chute end 6 above the level of the rims of the containers 5. The plate 64 acts as a product depressor or pickle pusher to assure that the product does not extend an objectionable distance above the container rims 5.

The cap drag wiper 25 on the front shoe 23 preferably is positioned as illustrated to engage the tops of the closure caps 7 for all common closure sizes. The wiper 26 on the rear shoe 27 is used as described above on the tops of the closure caps 7 for larger sizes of closures such as 53 mm to 82 mm.

However, for smaller closure caps such as those between about 27 mm and 48 mm, the wiper is preferably positioned to engage the skirt 1 7 of the closure caps 7 as a side wiper.

This alternative is illustrated for the wiper 65 in Figures 7 and 8.

Figure 5 is a vertical sectional view of the cap pickup point illustrating the cap retaining buttons 20. Each of the buttons 20 is mounted on a vertical shaft 60 in a "C" shaped holder 61 with the holders being urged inwardly by the force of the holder mounting leaf springs 21.

Figure 6 illustrates the action of the first turndown drag 25 and shows the drag 25 position subjecting the outer edge of the cap 7 cover to a drag or turning force.

It will be seen that an improved high speed cap pickup has been described for applying closure caps on high speed straight line sealing machines. The pickup is an improvement over prior pickups in that it applies the caps more evenly without their being cocked or misapplied to the moving containers and it operates satisfactorily on closely spaced containers moving at high speeds. Additionally the improved cap pickup has a more simple structure permitting continuous observation by the machine operator. The simplified design benefits from the elimination of cap reversing rubbers and cap supporting magnets which are commonly used on prior cap pickups.

Claims (12)

1. A cap feed pickup comprising a cap feeding chute end having cap supporting tracks on the cap chute end, a plurality of cap levelling shoes with a cap turning wiper on each shoe, and a cap cover contacting member positioned centrally of the cap chute end and above said cap tracks and positioned in combination with the said cap tracks to hold the endmost cap in an inclined position in the cap chute end with its forward most cap skirt portion positioned to engage containers on the container finish above the uppermost portions of the container cap engaging thread or lug members.

2. A cap pickup as claimed in Claim 1 in which said cap chute end is mounted for pivotal movement about two axes at right angles to one another with one axis being positioned generally transverse of the cap chute end and the other axis extending generally upwardly from the cap chute end.

3. A cap pickup as claimed in Claim 2 which further comprises resilient means for urging the cap chute end to swing downwardly while permitting its cap release end to move upwardly against the force of the resilient means and a removable shim on the cap pickup for determining the limit of the downward swing of said cap release end.

4. A cap pickup as claimed in Claim 1 or Claim 2 or Claim 3 which further comprises the combination of cap applying and levelling front and rear shoes, resilient means for mounting the shoes in serial position on a cap pickup frame, and means for adjustably determining the lowermost positions of the cap shoes.

5. A cap pickup as claimed in Claim 4 in which the means for adjustably determining the lowermost positions of the shoes comprise metal spacers removably positioned on shoe mountings.

6. A cap pickup as claimed in Claim 4 or Claim 5 in which friction cap wipers are mounted on each of said shoes.

7. A cap pickup as claimed in Claim 6 in which said wipers have downwardly facing friction surfaces for engaging an off-centre portion of the closure cap tops.

8. A cap pickup as claimed in Claim 6, in which the wiper on the front shoe has a downwardly facing friction surface, and the wiper on the rear shoe has an inwardly facing surface for engaging the skirt portions of the closure caps being applied.

9. A cap pickup as claimed in any of Claims 4 to 8 which further comprises an additional cap holddown means pivotally mounted on the rear end of the rear shoe and having a frictional turndown wiper for further engaging and maintaining the closure caps on the con tainer threads.

10. A cap pickup as claimed in any of the preceding claims in which the cap pickup comprises an elongated frame member extending centrally of the pickup and having its opposite sides positioned inwardly of and above the opposite sides of the said shoes whereby the shoes are visible to the machine operator.

11. A cap pickup as claimed in any of the preceding claims which further comprises an inclined product depressor plate mounted on the lower surface of the said chute end.

12. A cap pickup as claimed in any of the preceding claims which further comprises a cocked cap detector pivotally maintained thereon.

1 3. A cap feed pickup substantially as described herein with reference to Figures 1 to 6 of the accompanying drawings, with or without the modifications described herein with reference to Figures 7 and 8.