US3782525A

US3782525A - Feed mechanism

Info

Publication number: US3782525A
Application number: US00211013A
Authority: US
Inventors: E Flury
Original assignee: Individual
Current assignee: WR Grace and Co Conn
Priority date: 1971-12-22
Filing date: 1971-12-22
Publication date: 1974-01-01
Anticipated expiration: 1991-01-01

Abstract

The invention disclosed relates to a feed mechanism for bottle closure lining machines and employs a positive feed member resiliently supported by an oscillating carrier to effect advance of a closure towards the lining chuck. The invention enables much higher throughput rates to be achieved when lining closures with, for example, centrifugally distributed plastisol compositions. Preferably the feed member consists of a pair of laterally spaced closure striking pins.

Description

United States Patent Flury Jan. 1,1974

[ FEED MECHANISM [76] Inventor: Edwin Flury, 15 Heatherley Dr.,

Clayhall, England [22] Filed: Dec. 22, 1971 21 Appl. No.: 211,013

smegma 25 Primary ExaminerRichard E. Aegerter Attorney-G. E. Parker et a1.

[57] ABSTRACT The invention disclosed relates to a feed mechanism for bottle closure lining machines and employs a positive feed member resiliently supported by an oscillating carrier to effect advance of a closure towards the lining chuck. The invention enables much higher throughput rates to be achieved when lining closures with, for example, centrifugally distributed plastisol compositions. Preferably the feed member consists of a pair of laterally spaced closure striking pins.

5 Claims, 4 Drawing Figures PATENTEUJAN 11914 1 sum a 0F 3 FEED MECHANISM This invention relates to feed mechanisms, and more particularly to am improved form of feed mechanism for advancing container closures such as bottle caps to a lining station at which a sealing liner will be applied to the inside of the caps.

Hitherto, in machines for lining the insides of container closures such as bottle caps, it has been customary for the closures to be allowed to fall down a delivery chute to arrive at an intermittently rotating indexing carrier which advances the closure to a position in register with the lining gun. However, such an arrangement has the disadvantage that merely allowing the closures to fall down a supply chute to arrive at the indexing carrier leaves it possible for the closures to become jammed due to only partial loading of a closure in the indexing carrier.

According to the present invention we provide a feed mechanism for a container closure lining machine, such feed mechanism incorporating a work table along which closures are to be fed, and closure drive means extending upwardly from below the work table and resiliently carried by an oscillating drive member. Such a feed mechanism may with advantage be used in conjunction with the conventional indexing carrier mentioned above.

Preferably the drive means may comprise at least two pins symmetrically laterally spaced with respect to the line of intended closure advances and resiliently carried by an oscillating support plate. Conveniently, said pins may be carried through the agency of coil springs which, upon resistance to movement of the upper ends of the associated pins, undergo longitudinal bending deformation.

Due to the mounting of the pins on a crank member, the movement of the upper end of each pin may suitably follow a closed path and the height of the pins be arranged such that the top part of each pin advances along a path portion above the work table and descends below the work table during the return stroke back to the start position for the next advancing phase, so the pin will not impact the next closure awaiting delivery.

The mechanism advantageously incorporates a stop member arranged to arrest the train of closures issuing from the feed chute so that the leading closure of the train is positioned ready for position indexing by means of the closure drive means. As the pins advance they cause the closure to move along the work table into the correct position with relation to the indexing member. The stop member may be resiliently biased upwardly whereby movement of the closure being fed causes the closure to depress the stop member and to ride over the depressed stop member during feed movement to the position of register with the indexing member. Desirably the stop member may comprise an upwardly projecting tooth at the free end of a substantially horizontal lever which is biased for movement in a direction tending to raise the tooth into a closure arresting position.

Suitably, means may be provided for adjusting the longitudinal positioning of the pins in relation to the oscillating drive member to vary the limits of the path of movement of the pins. More suitablywhere a pair of synchronously moving laterally spaced pins is employed they may be adjustable towards and away from one another.

Advantageously the oscillating drive member may include a support plate mounted on a crank arm, one end of the crank arm being slidingly received within a pivotally mounted block, and the other end of the crank arm being drivably connected to an eccentric member.

Conveniently the crank arm may be driven from a linking shaft arranged to drive several closure feed mechanisms simultaneously.

Means may also be provided for adjusting the throw of the crank arm by adjusting the eccentricity of the pivotal connection on the crank with relation to the linking drive shaft.

In order that the present invention may more readily be understood the following description is given, merely by way of example, reference being made to the accompanying drawings in which:

FIG. 1 is a side elevational view of a single feed mechanism showing the position of two successive closures being fed by the mechanism; and

FIG. 2 is a top plan view showing two adjacent separate feed mechanisms linked by a common drive shaft.

FIG. 3 is a partly sectioned'side elevational view of the closure-engaging pin assembly.

FIG. 4 is a partly sectioned side elevational view of j a stop member to be positioned at the end of a closure feed chute.

Referring now to the drawings, FIG. 1 shows a work table 1 along which a succession of

closures

2a, 2b etc. is advanced from the bottom of a guide chute 3. The left-hand closure 2a has arrived in register with an indexing turret 4 disposed below a top cover 5 which, to gether with the work table 1, defines a passage along which the closures are fed.

Three separate positions of feed pins 6 during a feed stroke are shown at 6a, 6b and 60, respectively.

As broadly shown in FIG. 1 and with more detail in FIG. 4, a substantially horizontal lever 7 has a transversely extending stop finger 8 mounted at its free end and is pivoted at its other end to a support spindle 9. A leaf spring 10 secured to the underside of the work table engages the free end of the lever 7 to urge the stop finger 8 upwardly into the position shown in FIG. 1. Thus, as each closure is moved from the 2b position to the Zn position, the train of closures in the guide chute 3 advances by one closure so that the leading closure of the train arrives in engagement with the stop finger 8 to be held there prior to the next positive feed stroke of the pins 6. The spindle 9 is supported at its ends within a bearing housing formed by a pair of lugs 11 secured to and extending downwardly from the work table 1.

The stop finger 8 is shaped so that the leading edge, i.e., the right-hand edge as viewed in FIGS. 1 and 4, engages against and arrestingly abuts the leftward edge of the closure while the upper and leftward edges of the finger are inclined so that as the cap arriving at the 2a position moves off the finger 8 the latter may rise more gently than it would if it had a sharp edge which suddenly jumps up once the cap has been removed therefrom.

The cap illustrated in FIGS. 1 and 4 has a substantially frusto-conical skirt which exerts a camming action on the upper edge of the almost vertical right-hand face of the stop finger 8. However, where the closures being fed have a substantially cylindrical skirt, it may prove necessary to provide an inclined stop face on the finger 8 in order to ensure that the cap can exert a camming action to push the finger down as the cap moves thereover.

The pins are each secured to a respective coil spring 12 carried by a support plate 13 which is secured to a main drive crank 14 by a pair of screws 15. An embodiment of such a pin-spring-plate assembly is illustrated by FIG. 3 in which a pin 6 is partly inserted into a coil spring 12 which in turn is partly wedged into a blind hole on support plate 13. The drive crank 14 has one end freely slidably carried within a block 16 including trunnions l7 pivotally supported by a pair of upstanding lugs 18 secured to the machine frame 19. As shown in FIG. 2, the support plate 13 carrying the pins extends laterally to one side of the operating crank 14.

The other end of the drive crank 14 is integrally formed with the outer housing 20 of a bearing assembly the inner member 21 of which is keyed at 22 to a linking drive shaft 23 positioned eccentrically of the inner roller member 21. Thus, upon rotation of the drive shaft 23, the inner member 21 will orbit about the axis of the shaft 23 and will thus cause the centre of the outer housing 20 to execute a similar orbiting action while the housing 20 itself is constrained against completely free rotation by its connection to the drive crank 14.

The inner member 21 has a pair of thrust washers 24 secured thereto, for example by suitably located screws (not shown), in order to limit end float.

The eccentricity of the roller 21 will usually be fixed but by substitution of a differently shaped roller it will be possible to effect a different throw for the crank 14.

From the above description, and the illustration of FIG. 1, it can be seen that upon rotation of the shaft 23 through 180 degress in the anti-clockwise direction from the FIG. 1 position, the pins 6 will move rightwardly from the 60 position and during the first 90 of shaft movement the pins will be descending. During the second 90 of shaft movement the pins will still be moving rightwardly and as they approach the 6a position their rightward movement will become slower and they will begin to rise. The dotted line 25 showing the path of movement of the tip of one of the pins indicates that the pins do not execute a true elliptical motion but instead follow a closed path arranged so that during the greater part of their retraction movement they are disposed below the work table 1 and then during the whole of their advancing movement they are disposed above the table. The reason for this deviation from a true elliptical path is that, as the crank 14 moves rightwardly during the above described l80 of anticlockwise shaft movement, the pins become closer to the fixed axis of the shaft 23 and further from the axis of the trunnions 17 of block 16. Whereas the angular position of the longitudinal axis of drive crank 14 will execute a simple harmonic motion aout the axis of trunnions 17 and the pins 6 will also execute a simple harmonic motion in their movement along this longitudinal axis towards and away from the axis of the trunnions 17, the combination of these two movements will be such as to provide the illustrated closed path 25 having one sharp end and one blunt end.

The left-hand part of FIG. 2 shows one feed mechanism in association with a first indexing member of the cap lining machine, and the right-hand part of the figure shows a second feed mechanism associated with a second indexing member the two parts of the machine and indexing members being synchronised to allow alternate sides of the machine to feed caps to respective lining stations. The left-hand part of the machine is shown with the pins 6 in the retracted position whereas the right-hand part of the machine shows the simultaneous configuration in which the pins are in the advanced position. This alternating action of the two feed mechanisms provides for a much more smoothly balanced and hence quieter operation of the machine.

At the left-hand end of the machine the drive crank 14 has its pivoted end drilled to receive a journal bearing bush 27 receiving a journal pin 28 having a square head 29. The end of the pin 28 oppposite the square head is engageable within an eccentric aperture 30 of a disc 31 mounted at the left-hand of the linking drive shaft 23 and is locked in position by a grub screw (not shown). The shaft 23 is shown in FIG. 2 as being supported by three spaced anti-friction bearings 32, 33 and 34, and further additional bearings may be provided to the right of the bearings 34, if required.

Although not shown in FIG. 2 the pins 6 are adjustable towards and away from one another to accommodate different sized caps therebetween. Clearly, the optimum positioning of the pins with relation to the cap will be such that the two transversely spaced pins engage the cap in such a way that they subtend an angle of approximately 90 at the centre of the cap and are disposed symmetrically about the cap diameter which is parallel to the direction of advance. This will mean that the spacing between the pegs will be approximately percent (i.e., k 2) of the cap diameter and can be adjusted to suit the varying cap sizes. Clearly, if the size of cap to be fed is increased then, once the pins 6 have been correctly spaced to accommodate the larger cap it may be necessary subsequently to adjust the position of the pin supporting plate 13 longitudinally of the drive crank 14. This will have the effect of shifting the extreme ends of the closed pin tip path 25 and also of increasing or decreasing the vertical travel of the pin tips during their motion. Thus the path 25 will be either made fatter or thinner depending on whether the pins are moved away from or towards the axis of the trunnions 17. The pin tip path adjustment is achieved by slackening the bolts 15 and sliding the plates longitudinally of the crank within the limits defined by the slots 35 shown in FIG. 2. In this way the path of the pins 6 longitudinally of the pairs of slots 37 in the work table 1 can be adjusted to ensure that the spacing between the pair of pins and the stop finger 8 in the starting position 611 of the pins 6 is correct in relation to the diameter of the cap. Naturally, if the pins 6 were too close to the stop finger 8 the pins would be unable to engage behind the cap to urge the cap forwardly.

Although the particular embodiment illustrated in FIGS. 1 and 2 employs feed pins which are mounted on coil springs so that the resilience of the feed pins is derived solely from bending formation in the coil springs 12, any other suitable resilient form of mounting for the pins is envisaged as lying within the scope of the invention. For example, the pins could be mounted on leaf springs which are secured to the plate 13.

FIG. 1 shows that the right-hand end of the drive crank of FIG. 2 is constructed in two parts, a first 14a of which is integral with the outer bearing housing 20 and a second 14b is in the form of a rod which is slidingly received within the trunnioned block 16. A screw 38 shown in FIG. 1 but omitted from FIG. 2 engages the front end of the rod portion 14b to secure the two portions of the crank together. The difference in details between the eccentric systems of the two drive cranks 14 arises for two reasons. Firstly it is necessary for the linking drive shaft 23 to extend rightwardly to a chaindrive sprocket supplying driving torque from the main drive of the cap lining machine; the chain and sprocket transmission to the drive shaft 23 may of course be replaced by any other suitable transmission which ensures accurate synchronisation between the shaft 23 and the main drive shaft of the cap lining machine. Secondly, the particular arrangement employed enables the machine to be readily dismantled and re-assembled either for maintenance or for substitution of a different eccentric inner roller member 21 whose eccentricity may be different in order to achieve a different throw for the crank 14. For example, whereas the left-hand drive crank maybe removed simply by unscrewing the journal pin 28 and then sliding the crank 14 out from the trunnioned block 16, dismantling of the right-hand drive crank is effected by removing the screw 38, slid ing the rod portion 14b leftwardly as viewed in FIG. 1 to remove it from the other crank portion 14a and then releasing the drive shaft 23 from its hearings to be lifted vertically out of the machine.

The provision of spring-loaded feed pins 6 ensures that both the drive crank mechanism and the caps are spared the high loads to which they would otherwise be subjected if a closure were to jam on a machine employing a completely rigid connection of the pins 6 and shaft 23. If jamming occurs in the machine illustrated in FIGs. l and 2, the spring loaded pins 6 can still execute their feed movement but the caps will be retained stationary and the lack of caps delivered from the lining head will draw the operators attention to the existence of a stoppage. Naturally, any suitable form of automatic signalling system may be provided in order to warn the operator of such a stoppage.

The value of the maximum dirving force to be imparted on the cap by the spring-loaded pins may need to be varied in which case the springs 12 may be replaced by other springs of a stronger rate. Thus the feeding force can be adjusted to ensure positive feed without undue damage to either the cap or the mechamsm.

The pin mounting mechanism may be varied, for example by providing the pins 6 in the form of plungers which are spring-urged in an upward direction and mounted within sleeves which are themselves secured in a manner similar to that of the pins 6 in the apparatus illustrated. With this arrangement the pins are resiliently urged axially of their length, so that they can retract should the caps be fed to the chute 3 intermittently thus preventing jamming of the machine and damage to the caps.

The advantages of the feed mechanism of the present invention includes the following:

1. The use of a positive drive to forward the caps into the indexing carrier turret 4 enables a much higher speed of operation to be achieved since the loading of caps into the indexing turret no longer depends upon the gravitational force acting on a train of caps in the vertically disposed chute 3. Thus employing a feed mechanism of this sort enables a more rapid and positive engagement of the leading cap with the turret.

2. By providing an arrangement in which the cap feeding pins engage the outside of the caps rather than the inside, it has been ensured that no damage will be sustained by the delicate inner surface of the cap which in most cases has been previously lacquered in order both to impove bonding of the plastisol composition to the metal of the cap and to prevent corrosion of the metal of the cap. Damage to this enamel lining would otherwise lead to subsequent corrosion.

3. The use of pins driven from below enables the top of the machine to be free of any mechanisms which would otherwise hinder removal of a jammed closure. With the present system, the top cover 5 over the work table may simply be pivoted away in order to expose the whole of the work table, the indexing mechanism and the row of closures thereon.

4. By providing two separate pins moving along a feed path in laterally spaced configuration, it is ensured that the cap can be centralised during feeding. Besides the pins 6 can, as explained above, be adjusted for accommodating caps of different diameters.

5. The provision of pins engaging the outside of the cap ensures that the pins contact the cap at or near the boundary between the disc like top of the cap and the skirt, thereby ensuring that the driving force exerted on the cap is absorbed at the strongest point of the cap. Since the pins 6 engage the outside of the cap while the cap rests mounted on the work table, the drive mechanism itself will require no adjustment to accommodate caps of dif ferent heights. However, the clearance between the top cover 5 and the work table 1 may require adjustment.

We claim:

1. A feed mechanism for a container closure lining machine, such mechanism incorporating: a work table along which the closures are to pass; closure drive means extending upwardly from below the work table comprising at least two pins symmetrically laterally spaced with respect to means defining a path of closure advance; an oscillatable drive member; means resiliently mounting said drive means on the drive member; a feed chute down which a train of closures passes onto the work table; a stop member arranged to arrest the train of closures issuing from the feed chute, with the leading closure of said train being positioned ready for indexing by the drive means; and means for driving said drive member in oscillatory motion.

2. A feed mechanism according to claim 1, wherein said means resiliently mounting the pins comprise coil springs supporting said pins which are capable, upon resistance to movement of the upper ends of the associated pins, to undergo longitudinal bending deformation.

3. A feed mechanism according to claim 2, wherein a further coil spring is provided for each pin, to accommodate axial retracting movement of the pin.

4. A mechanism according to claim ll, wherein said stop member is resiliently biased upwardly whereby feed movement of the closure being driven by the closure drive causes the closure to depress the stop member and drive means ride over the depressed stop member during feed movement.

5. A mechanism according to claim 1, wherein said stop member comprises a substantially horizontal lever, an upwardly projecting tooth at the free end of said lever and means biasing said lever for movement in a direction tending to raise the tooth.

* t i l

Claims

4. A mechanism according to claim 1, wherein said stop member is resiliently biased upwardly whereby feed movement of the closure being driven by the closure drive causes the closure to depress the stop member and drive means ride over the depressed stop member during feed movement.