Abstract:
This invention relates to a method and apparatus for applying a strong elastic sleeve on an article. Especially if the elastic sleeve is very strong and the article is somewhat fragile. It is intended for the container industry, but may have other uses.

Description:
This application is a continuation of Ser. No. 897,586 filed Aug. 15, 1986, now abandoned. 
    
    
     FIELD OF THE INVENTION 
     This invention relates particularly to the container industry and more particularly to containers of the aerosol type. However, it may have other fields of use. 
     BACKGROUND ART 
     The common aerosol type of container uses gas under pressure to propell the contents out of the container when a valve is actuated. 
     The type of container for which this method and apparatus is designed, uses an elastic sleeve to obtain the pressure needed rather than a gas. Such a container is described in U.S. Pat. No. 4,423,829, issued to Hyman Katz. 
     The elastic sleeve is usually made of rubber and has an inside diameter much smaller than the diameter of the container on which it is applied, and the wall of the elastic sleeve is quite thick. It requires considerable force to expand the elastic sleeve in order to apply it to the outside of the container. The container is usually made of thin film and must be carefully manipulated, so as not to damage it while applying the sleeve. 
     The method and apparatus used to date to apply the sleeve to the container has been complicated and expensive and has not been entirely successful for the purpose. 
     This invention provides a satisfactory means to accomplish the application of the sleeve to the container. This invention is not limited to the use shown here. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of an elastic sleeve of the type for which this invention applies; 
     FIG. 2 is an end view of the elastic sleeve shown in FIG. 1, showing the approximate proportions of inside diameter to outside diameter and has been drawn to the same scale as the container shown in FIG. 3 to which it is to be applied; 
     FIG. 3 illustrates a typical container to which the elastic sleeve is to be applied; 
     FIG. 4 shows a container after an elastic sleeve has been applied; 
     FIG. 5 is an enlarged section on line 5--5 of FIG. 4; 
     FIG. 6 is a view on line 6--6 of FIG. 15. This view would also be nearly identical to a mirror image of a view taken on line 6A--6A of FIG. 15. All components shown in both views would be alike, except for a linkage connection; 
     FIG. 7 is a section taken on line 7--7 of FIG. 6; 
     FIG. 8 is a section taken on line 8--8 of FIG. 6; 
     FIGS. 9, 10, 11, 12, 13 are diagramatic views, partly in section, to show successive stages in the process of applying the elastic sleeve to the container; 
     FIG. 14 is a side elevation view of the complete machine showing the actuation cams and motor drives; 
     FIG. 15 is an elevation of the machine looking at the cam shaft end; 
     FIG. 16 is a small section taken on line 16, 16 of FIG. 15; 
     FIG. 17 is a small section taken on line 17, 17 of FIG. 15. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 shows an elastic sleeve such as is to be applied to a container 2 shown on FIG. 2. 
     FIG. 3 shows a container 2 on which an elastic sleeve 1 has been applied. The elastic sleeve 1 is usually made of natural rubber of the type known as pure gum. The container 2 is usually made by the blow molding process and is made of thin plastic film and is corrugated as shown in section on FIG. 5. Referring to FIGS. 6 and 8, there are two end plates, one upper end plate 3 and a lower end plate 4. Both end plates 3 and 4 are mounted on a pair of slide rods 5. The slide rods are attached at the ends to frame 6. The upper plate 3 is fixed in place and held by set screws 7. The lower plate 4 slides on slide rods 5 and is moved in a vertical direction by two links 8, and two levers 9, that are attached to shaft 10. Also, attached to shaft 10 is a central lever 11, that is connected by links 12 to a lever 13, that is pivoted on shaft 14. One arm of the lever 13 has a cam roller 14a that is in contact with cam 15. The cam 15 is attached to cam shaft 16, which is rotated by means of belt pulley 17 and belt 18, and motor drive unit 19. 
     Refer again to FIG. 8. There is an arbor 20, arranged to receive the elastic sleeve and it fits the inside diameter of the elastic sleeve, tight enough to retain the elastic sleeve without it falling off. The arbor 20 is tubular, and it has a passage 21 through its axis for the passage of fluid. The arbor is attached pivotably to a rotating joint 22, to which is connected a tube 23, which in turn is connected to a source of fluid pressure (not shown). 
     A tubular receptacle 24 is provided to receive a container 2, placed there by an operator. The receptacle 24 is slidable, mounted in slotted tube 25 that is attached to frame 6, by supports 26. The tubular receptacle is moved vertically by means of links 27, and lever 28 that is pivoted on shaft 29 and has extension lever 30 attached thereto on which is mounted cam roller 31 that is in contact with cam 32. Spring 32a assists in keeping the cam roller 31 in contact with the cam 32. 
     Referring to FIG. 8, the upper plate 3 and the lower plate 4, each have four slide elements 33. The said slide elements 33 have shaped ends arranged for pinching the ends of the elastic sleeve so it may be expanded by fluid pressure. The slide elements 33 in the upper plate 3 pinch the elastic sleeve 1 against the arbor 20, whereas the slide element 33 in the lower plate 4 pinch the elastic sleeve against itself with nothing in the inside diameter. 
     Refer to FIG. 6. The movement of the slide elements 33 in a direction towards or away from the axis of the arbor 20 is actuated by links 34, lever 35b, 36b, 37 and 38, and links 39 and air cylinders 40. Both end plates 3 and end plates 4 have identical actuating apparatus for the slide elements 33. 
     The slide elements 33 are slotted and carry pivoted prong levers 36, said prong levers have attached integral therewith prongs 35 of a diameter small enough so that the four prongs 35 will fit into the inside diameter of the ends of the elastic sleeve 1, that are not expanding sufficiently by the fluid pressure. The prong levers are actuated by air cylinders 36a, that are also attached to slide elements 33, by bracket 37. 
     Spaced between end plates 3 and 4 are a number of intermediate plates 37a which are carried on rods 38, said rods 38 are fitted tight in lower plate 4, but slide in holes in upper plate 3. The intermediate plates 37a are spaced apart at the desired distance by spiral springs 39. Certain of the spiral springs may be made stronger than others to help control the rate of collapse of the elastic sleeve. The end plates 3 and 4 and the intermediate plates 37a all have a central hole 41, that is of a size somewhat larger than the container 2. The size of the hole 41 is determined by the clearance needed for inserting the container 2 into the expanded elastic sleeve. 
     The receptacle 24 is tubular and carries an ejector rod 40 through its inside diameter. The ejector rod is actuated by means of links 31, cam lever 42, that is pivoted on shaft 43 to which is attached lever 44, cam roller 45 that is in contact with cam 46. 
     A cooperating ejector 47 with a concave end 48 is attached to the rotating joint at a point approximately 90° to the attachment of the arbor 20. The rotating joint 22 is mounted pivotably on a sliding block 48 that slides on a flat bar 49. The flat bar 49 is attached by supports 50 to frame 6. The sliding block 48 is moved in a vertical direction by means of links 51, lever 52. link 53, lever 54, and lever 55, which carries cam roller 56 that contacts cam 57. A spring 58 is provided to overcome the weight of the sliding block 48 and keep the cam roller 56 in contact with cam 57. The arbor 21 and ejector 47 are pivoted and selectively brought into the proper position as needed in the machine cycle by air cylinders 58 and lever 59. 
     THE OPERATION OF THE APPARATUS 
     An elastic sleeve is placed on the arbor 20 and a container 2 is placed in the receptacle 24 by an operator, or this can be done by a robot or other mechanical means. The arbor 20 then moves into a position illustrated in FIG. 9, where the elastic sleeve 1 is pinched and expanded by fluid pressure fed through passage 21 into the interior of elastic sleeve 1. The elastic sleeve 1 is expanded to the extent that it contacts the holes in plates 3, 4, and 37a, and bulges into the spaces between the plates. Plate 4 then moves vertically to a position shown in FIG. 10, to compress the bulges in the elastic sleeve 1 with enough force to maintain the elastic sleeve 1 in the expanded state, then the fluid pressure is released and the arbor 20 is retracted to its initial position. 
     Refer to FIG. 11. The expansion of the elastic sleeve 1 may not be sufficient at the ends to allow the container 2 to enter properly, so prongs 35 are provided and actuated by the air cylinders 36a to penetrate the ends of elastic sleeve 1. Then the slide elements 33 are moved outwardly to stretch open the ends of the elastic sleeve 1. after which, the container is moved into the position shown in FIG. 12, by means of the ejector 40. At which time in the cycle, the cooperating ejector 47 is brought into position to properly center and position the container 2. 
     Refer to FIG. 13. The prongs 35 that are located in the lower plate 4 are next retracted by the respective air cylinders 36a, and the force on plate 4 is relaxed as controlled by cam 15, to allow parts of the elastic sleeve 1 to collapse on the container 2. The spiral springs 39 may be different strengths so as to allow parts of the elastic sleeve 1 to collapse progressively as the ejector 47 pushes the container 2 downward out of the location in the holes in the plates 39. Also, the tendency of the elastic sleeve 1 to return to its initial length will operate to spread the elastic sleeve 1 evenly lengthwise on the container 2. 
     When the container 2 with its applied elastic sleeve 1 has been pushed down sufficiently, it will fall free and ejector 40, being retracted to the position shown in FIG. 13, will prevent the container 2 from entering the receptacle 24. The container 2 will be ejected from the apparatus and may be directed to fall to a desired location (by means not shown). 
     The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, as modifications will be obvious to those skilled in the art.