GB2121015A - Opening and closing containers - Google Patents

Abstract

An apparatus for opening and closing hermetical containers eg. for nuclear fuels or microorganisms, having a closure cap 10 attached to the main body of the container by a bayonet engaging structure 11, comprises a support device for upwardly and downwardly moving and reversibly rotating the container as supported thereon, a handling box 8 positioned above the container supported on the device, a cover plate 24 provided in a bottom opening of the handling box, a lift rod 26 extending through the cover plate 24 and adapted to move upward and downward limitedly while being restrained from rotation, and an operation disk 35 fixed to the lower end of the lift rod and engageable with the closure cap 10 by a bayonet engaging structure 19, 38. The operation disk 35, which is upwardly and downwardly movable independently of the cover plate 24, does not cause so-called "galling" when brought into or out of engagement with the closure cap 10 by rotation. <IMAGE>

Description

SPECIFICATION Apparatusforopening and closing hermetical con tainers The present invention relates to an apparatus for opening and closing hermetical containers for containing used nuclearfuels, microorganisms, etc. for storage ortransport, and more particularly to an apparatus for opening and closing a hermetical containerwhich is useful for such a purpose and which comprises a container main body having a circular open upper end and a circular closure cap hermetically attached to the open upper end of the main body by bayonet engaging means and a seal.

An opening and closing apparatus for such hermetical containers is already known which comprises a supportdeviceforvertically moving and reversibly rotating the container as supported thereon, a fixed base plate having an opening immediatelyabovethe upper end ofthe containersupported on the device, an annular plate hermeticallyto the opening portion of the base plate and centrally formed with an opening for permitting the closure cap ofthe container to pass therethrough,the annular plate having an annular positioning flange adapted to fit around the upper end ofthe container, a cover plate hermeticallyfittable into the opening ofthe annular plate from above and fixedly provided on its lower side with an operation disk engageable with the closure cap of the container by bayonet engaging means, and lift means for lifting or lowering the cover plate.

To open the hermetical container by the apparatus ofthe above construction, the container main body is first lifted bythesupportdeviceto bring the open upper end of the main body into pressing contact with the lower surface ofthe annular plate. At this time, the closure cap is held attached to the open upper end of the container main body by bayonet engaging means, while the bayonet engaging means between the cap and the operation disk is in disengaged state. The container main body is then rotated forward by the supportdevice,wherebythe bayonet engaging means between the closure cap andthe main body is disengaged, butthe bayonet engaging means between the cap and the operation disk is engaged.

When the cover plate is finally lifted by the lift means, the closure cap can be removed from the container main body, with the open upper end of the main body held in pressing contact with the annular plate, i.e., in sealed contact therewith.

Thebayonetengaging means between the closure cap andthe operation disksomprises inward projectionsformed on the inner periphery of the cap to define a circular cavity in its upper surface and arranged equidistantly circumferentially thereof, and outward projections formed on the outer periphery of the operation disk at an equal spacing circumferential lythereofand having tongues which are positionable underthe inward projections in the circular cavity by rotation. With the known apparatus, however, the operation disk is fixed to the cover plate, so that it is impossible to suitably adjust the clearance, in vertical direction, ofthe bayonet engaging means between its inward projection and tongue.Thus ifthe parallelism between the cap and the operation disk is impaired for one cause or another (for example, if the container main body is not vertical), "galling" occurs between the inward projection and the tongue when they are rotated relative to each other, making it very difficult to bring the operation disk into or out of engagement with the cap.

An object ofthe present invention is to provide an apparatusforopening and closing hermetical containers ofthe type described by which the closure cap can be opened and closed smoothly at all times even if the cap and the operation disk have impaired parallellism therebetween.

To fulfill the above object, the present invention provides an apparatus for opening and closing hermetical containers which comprise a container main body having a circular open upper end and a circular closure cap hermetically attached to the open end ofthe main body by bayonet engaging means and a seal,the apparatus comprising a support device for upwardly or downwardly moving and reversibly rotating the container as supported thereon, a fixed base plate having an opening immediately above the upper end ofthe container supported on the device, an annular plate hermetically attached to the opening portion ofthe base plate and centrally formed with an opening for permitting the closure cap ofthe container to passtherethrough, the annular plate having an annular positioning flange fittable around the upper end ofthe container, a cover plate hermeticallyfittable into the opening ofthe annular plate from above and centrally having a guide bore, a lift rod extending through the guide bore of the cover plate and adapted to move upward and downward limitedlywhile being restrained from rotation, spring means for biasing the lift rod upward againstthe cover plate, and an operation diskfixed to the lower end of the lift rod and engageable with the closure cap ofthe container by bayonet engaging means.

With the opening and closing apparatus of the above construction, the operation disk is provided independently ofthe cover plate and is movable with the lift rod to vary the distance between the disk and the cover plate, so that outward engaging tongues on the operation disk can be positioned under, and spaced apart from, inward projections on the closure cap when the bayonet engaging means between the disk and the cap is engaged and disengaged by rotation. Consequently, the operation disk can be broug ht into or out of engagementwith the closure cap smoothly.

Various features and advantages ofthe present invention will become apparentfrom the preferred embodiments to be described below with reference to the accompanying drawings, in which: Fig. lisa diagram showing a container opening and closing apparatus ofthe present invention in its entirety; Fig. 2 is a front view in vertical section showing a first embodiment ofthe invention before a closure cap is removed from a container main body; Fig. 3 is a fragmentary front view in vertical section showing the same during the removal of the closure cap; Fig. 4 is a fragmentaryfront view in vertical section showing the same immediatelyafterthe removal of the closure cap;; Figs. 5to 7 are fragmentary plan views in cross section ofthe same to illustrate the removal ofthe closure cap stepwise; Figs. 8 to 10 are views showing a second embodiment ofthe invention and corresponding to Figs. 2 to 4, respectively; and Figs. 11 to 13 are fragmentary plan views in cross section ofthe same to illustrate the removal of the closure cap stepwise.

With reference to Fig. 1 schematically showing the overall construction of a container opening and closing apparatus according to the present invention, a truck 1 is movably provided on a pair of rails 2. The truck 1 has a supporttable 3 which is movable upward and downward and reversibly rotatable. Avertically extending, generally cylindrical, hermetical container 4 is placed on the supporttable 3. A plurality of pairs (e.g. two pairs) of posts 5 are arranged longitudinally of the rails 2 at a spacing. Atop plate 6 having a central opening 7 is fixedly supported bythe upper ends of these posts 5. A closed handling box 8 its further provided on the top plate 6.

As shown in Figs. 2 and 5, the hermetical container4 comprises a container main body 9 having a circular open upper end and a circular closure cap 10 fittingly engaged in the open upper end of the main body9 by bayonet engaging means 11. An annular seal holder 12 is provided around the upper end of the main body 9. The cap 10 is attached to the main body 9 as sealed off by an annular seal 13 held by the holder 12.The bayonet engaging means 11 comprises inward projections 14formed on the inner periphery of the open upper end ofthe main body9 atan equal spacing circumferentially thereof, having a predetermined length in the circumferential direction and each having contact faces 14A, 14B at circumferentially opposite ends, and outward projections 15 formed on the outer periphery ofthe closure cap 10 at an equal spacing circumferentially thereof and having a circumferential length slightlysmallerthan the distance between two adjacent inward projections 14.Each of the outward projections 15 includes an engaging tongue 16 having a small thickness and positionable underthecorresponding inward projection 14by rotation and a thick portion 17 having contactfaces 17A, 178 adapted for contact with the contactfaces 14A, 14B oftwo adjacent inward projections 14 by rotation. The closure cap 10 has a circular cavity 18 formed in the central portion of its upper side. Inward projections 19 having a predetermined circumferential length are formed on the inner periphery defining the cavity 18 and are arranged at an equal spacing circumferentially thereof. Each ofthe inward projections 19 has contact faces 1 9A, 1 9B at circumferentially opposite ends.

The handling box 8 has a base plate 20 fixed to the top plate 6 and formed with an opening immediately above the upper end ofthe container. An annular plate 21 centrally formed with an opening for permitting the closure cap 10 to pass therethrough is fixed to the opening portion of the base plate 20, with a seal 22 provided therebetween. The annular plate 21 is integral, on the lower side, with an annular positioning flange 23fittable around the upper end ofthe container 4. A cover plate 24 is fitted in the opening portion ofthe annular plate 21 from above, with a seal 25 provided therebetween. The cover plate 24 has a guide bore in its center.A lift rod 26 adapted to move upward and downward limitedly extends through the guide bore,with an oilless bush 27 fitted in the bore around the rod. The lift rod 26 is restrained from rotation by a slide key 28. The rod 26 is fixedly provided with a bellows holding plate 29. A bellows 30 is provided between the holding plate 29 and the cover plate 24. A spring holding plate 31 positioned above the bellows holding plate 29 is fixed to the holding plate 24, with the lift rod 26 extending through the plate 31 vertically movably. The rod also extends through a lower spring seat 32 vertically movably which seat is fixed to the spring holding plate 31. A spring 34 is interposed between the lower seat 32 and an upper spring seat 33 which is fixed to the lift rod 26.

The spring 34 actsto pressthe cover plate 24 against the annular plate 21 in hermetical contact therewith.

An operation disk 35 projectable into the circular cavity 18 ofthe closure cap 10 is fixed to the lower end ofthe lift rod 26. Outward projections 36 having a circumferential length slightly smallerthan the distance between two adjacent inward projections 19 of the closure cap 10 areformed on the outer periphery ofthedisk35andarranged atan equal spacing circumferentiallythereof. Each ofthe outward projections 36 includes an engaging tongue 37 having a small thickness and positionable underthe corresponding inward projection 19 by rotation and a thick portion 38 having contact faces 38A, 388 adapted to abutagainstthecontactfaces 19A, of two adjacent inward projections 19 by rotation.The inward projections 19 of the closure cap 10 and the outward projections 36 ofthe disk 35 provide second bayonet engaging means 39. A horizontal arm 40 fixed to an intermediate portion ofthe lift rod 26 has a sensor rod 41 which coacts with a limit switch 42 and which is adjustable in its position. By the cooperation ofthe sensor rod 41 and the limit switch 42, the lower limit position ofthe disk 35, i.e., the gap G between the disk 35 and the cover plate 24, can be maintained as specified. Vertical guide rods 43 are fixed to the cover plate 24.

The operation of the apparatus of the foregoing construction will be described below.

Fig. 2 shows the hermetical container4 as it is being lifted by the supporttable 3. Atthistime, the disk 35 is held in position belowthe plate 24 away from the plate 24 bythe predetermined gap G, bythedescentofthe lift rod 26 against the force of the spring 34 and the action ofthe sensor rod 41 on the limit switch 42. The cover plate 24 is pressed againstthe annular plate 21 with the seal 25 interposed therebetween, by the force ofthe spring 34which is compressed by an amount corresponding to the gap G.

The supporttable 3 further lifts the containerto bring the seal 13 into pressing contact with the lower surface ofthe annular plate 21 as shown in Fig. 3. At this time, the outward projections 36 ofthe disk 35 passthe spaces between the inward projections 19 of the closure cap 10, permitting the disk 35 to be positioned in the circular cavity 18 of the cap 10. The second bayonet engaging means 39 is still in disengaged state as shown in Fig. 5, while the first bayonet engaging means 11 is in engaged state, with the outward engaging tongues 16 ofthe cap 10 positioned under, and spaced by a gap g from, the inward projections 14 ofthe container main body 9. Thus the closure cap loins in engagement with the container main body 9.

In this state, the container4 is rotated by the support table 3forward (counterclockwise) through a predetermined angle 61 as indicated by an arrow A in Fig. 6.

The cap 10 is pressed on by the two seals 13 and 25, but when the pressure of the seal 25 on the cap 10 is greaterthan the pressure of the seal 13 on the cap 10, the cap 10 is held against rotation, permitting the container main body 9 onlyto rotate th rough the angle 61. This disengages the first bayonet engaging means 11, bringing the contact face 14A of each inward projection 14 ofthe container main body 9 into contact with the contact face 1 7A of the outward thick portion 17 opposed thereto of the cap 10. At this time, the second bayonet engaging means remains disengaged since the cap 10 is held against rotation.

When the container4is further rotated forward through a predetermined angle 62 by the support table 3 as indicated by an arrowA in Fig.7,the cap 10 rotates with the main body 9 because the inward projections 14 ofthe main body 9 are now in contact with the outward thick portions 17 of the cap 10 at the contact faces 14A, 17A. This engages the second bayonet engaging means 39, positioning the outward engaging tongues 37 ofthe disk 35 underthe inward porjections 19 of the cap 10.At this time, the cap 10 is smoothly rotatable relative to the disk 35 without entailing "galling" even if the cap 10 and the disk 35 have impaired parallelism therebetween because there is the gap g between the inward projections 19 andthetongues37.

When the lift rod 26 is raised as shown in Fig. 4 by an unillustrated lift in this state, the gap g between the inward projections 19 and the engaging tongue 37 is eliminated, and the disk 10 is raised by the rod 26 through the opening ofthe annular plate 21. In this step,theforceofthe spring 34 pressing the cover plate 24 againstthe annular plate 21 through the seal 25 changes to a force for pressing the cap 10 against the cover plate 24 th rough the seal 25, with the resultthat the space between the cap 10 and the cover plate 24 is held sealed offandthereby protected from the contaminated atmosphere within the handling box 8.

On the other hand, the container main body 9 and the handling box 8 define a space which is sealed off by the seal 13, so that if the rod 26 is further lifted, a pollutant can be transferred between the main body 9 and the handling box 8 without causing air pollution.

Conversely the closure cap 10 can be fitted to the main body 9 by a procedure reverse to the above.

Next, a second embodiment of the invention will be described with reference to Figs. 8 to 13. Throughout the accompanying drawings, like parts are referred to by like reference numerals, and a description will not be given exceptwhere necessaryfor different features.

With reference to Figs. 8to 11,the annular seal holder 12 has outward projections 44 having a predetermined length circumferentiallythereof and formed on the outer periphery of its upper end at an equal spacing along the circumference. An independent positioning flange 23 is fixed to the lower side of the annular plate 21. Theflange 23 is provided on its inner periphery with inward projections 45 arranged at an equal spacing circumferentially thereof and having a circumferential length slightlysmallerthan the distance between two adjacent outward projections 44 on the seal holder 12.The outward projections 44 of the seal holder 12 and the inward projections 45 in the flange 23 provide third bayonet engaging means 46 (Fig. 9). The annular plate 21 is connected to the base plate 20 hermetically and tiltably by a bellows 47 and a tilting plate 48.

A horizontal movable plate 49, which is guided by horizontal guide rods 50 via bosses 51, is disposed above the lift rod 26. A rack extending in parallel with the guide rod 50 is fixed to the movable plate 49 and is in mesh with a pinion. Afirst pinion drive assembly 52 having the pinion drives the movable plate 49. A vertical output rod 53 provided with a rack extends through the center ofthe movable plate 49. Asecond pinion drive assembly 54 fixedly mounted on the movable plate 49 and having a pinion meshing with the rack on the output rod 53 drives the output rod 53 upward and downward. A horizontal arm 40 fixed to the upper end ofthe output rod 53 carries an adjustable sensor rod 41. The sensor rod 41 is cooperative with a limit switch 42 fixed to the movable plate 49.The lower end of the output rod 53 is fixedly provided with a lift box 55, into which the upper end of the lift rod 26 extends. A semispherical bush 56 attached to the upper end of the lift rod 26 and a semispherical seat 57 formed in the box 55 constitute a universal joint. A jump preventing cap 58 fixedly provided within the lift box 55 prevents the lift rod 26 from jumping. Side plates 59 are attached to opposite sides ofthe box 55. Avertical guide rod 43 extends upward from each ofthe side plates 59 and is vertically movably supported buy a bearing 60 mounted on the horizontal movable plate 49. Springs 34 (only one shown) are interposed between the side plates 59 and the spring holding plate 31.Indicated at 61 are adjustable positioning bearings secured to the base plate 20 and adapted to bear against the upper end outer periphery ofthe container main body for positioning the container.

Next, the operation ofthe second embodiment will be described below. The same steps as in the first embodiment will not be stated in detail.

First, the hermetical container4is raised bythe supporttable 3 to the position of Fig. 8 andthen to the position of Fig. 9. At this time, the outward projections 36 ofthe disk 35 and the inward projections 45 ofthe flange 23 passthroughthe spaces between the inward projections 19 ofthe closure cap 10 and those between the outward projections 44 ofthe seal holder 12, respectively. Even if the top ofthe container4 is not in parallel with the annular plate 21 and the cover plate 24, the space between the container and the cover plate can be held sealed offbythe seals 13 and 25 at all times, since the annular plate 21 and the cover plate 24 are movable aboutthe semispherical bush 56.

Fig. 11 shows the container 4 immediately after the top ofthe container has been pressed into contact with the lower side ofthe handling box 8 as above. The first bayonet engaging means 11 is in engaged state, while the second and third bayonet engaging means 39,46 are in disengaged state. In this state, the container4 is rotated forward (counterclockwise) through a predetermined angle 01 by the supporttable 3 as indicated by an arrow A in Fig. 12. If the pressure between the seal 13 and the cap loins greater than the pressure between the seal 25 and the cap 10, the cap 10 rotates with the container main body 9. Consequently the first bayonet engaging eans 11 remains engaged, while the second and third bayonet engaging means 39,46 are engaged.

As seen in Fig. 13, the container4 isfurther rotated forward through a predetermined angle 62 by the table 3. Since the contactfaces 19A of the inward projec- tions 19 of the cap 10 are in contactwith the contact faces 38A of the outward thick portions 38 ofthe disk 35, the container main body9 alone rotates at this time. As a result, the first bayonet engaging means 11 is disengaged, with the second and third bayonet engaging means 39,46 remaining in engaged state.

Subsequently, the second pinion drive assembly 54 is operated to raise the output rod 53 (Fig. 9), whereby the assembly ofthe cap 10 and the cover plate 24 having the seal25 held therebetween is removed upward by the lift box 55, the rod 26 and the disk 35.

Consequently, the handling box 8 and the container main body 9 having the seal 13 therebetween form a containerofcombined structure. Next, thefirst pinion drive assembly 52 is operated to horizontallymovethe cap 10 and the cover plate 24 along with the movable plate 49. A pollutant can then be transferred between the container main body 9 and the handling box 8.

The container 4 is closed and separated from the handling box 8 by a procedure reverse to the above.

Claims (10)

1. An apparatus for opening and closing hermetical containers which comprise a container main body having a circular open upper end and a circular closure cap hermetically attached to the open end of the main body by bayonet engaging means and a seal, the apparatus comprising a support device for upwardly and downwardly moving and reversibly rotating the container as supported thereon, a fixed base plate having an opening immediately above the upper end ofthe container supported on the device, an annular plate hermetically attached to the opening portion ofthe base plate and centrally formed with an opening for permitting the closure cap ofthe container to pass therethrough, the annular plate having an annular positioning flange fittable around the upper end ofthe container, a cover plate hermeticallyfittable into the opening ofthe annular plate from above and centrally having a guide bore, a lift rod extending through the guide bore of the cover plate and adapted to move upward and downward limitedly while being restrained from rotation, spring means for biasing the lift rod upward againstthe cover plate, and an operation disk fixed to the lower end ofthe lift rod and engageablewith the closure cap ofthe container by bayonet engaging means.

2. An apparatus as defined in claim 1 wherein the base plate forms the bottom plate of a hermetical handling box.

3. An apparatus as defined in claim 1 or 2 wherein above the cover plate, a bellows holding plate is fixed to the lift rod, and a bellows is provided between the holding plate and the cover plate.

4. An apparatus as defined in any one of claims 1 to 3 wherein a horizontal arm movable with the lift rod upward and downward is provided, and the arm has a sensor rod adjustable in its position and cooperative with a limit switch for detecting the lower limit position ofthe lift rod.

5. An apparatus as defined in any one of claims 1 to 4wherein the upper end ofthe lift rod extends into a lift box coupled to lift means and is connected to the lift box by a universal joint, and the annular plate is tiltably connected to the base plate by a tilting plate fixed to the annular plate and a bellows provided between the tilting plate and the base plate.

6. An apparatus as defined in claim 5 wherein the universal joint comprises a semispherical bush attached to the upper end ofthe lift rod and a semispherical seat formed in the lower side ofthe lift box and complementaryto the bush, and the lift box is provided in its interior with a cap for preventing the lift rod from jumping.

7. An apparatus as defined in claim 5 or 6 wherein the lift means comprises a pinion drive assembly fixed to a horizontal movable plate along a pair of fixed horizontal guide rods, and a vertical rod having a rack in mesh with a pinion ofthe pinion drive assenblyand extending through the horizontal movable plate, the vertical rod being connected to the lift box.

8. An apparatus as defined in claim 7 wherein another rack is mounted on the horizontal movable plate and which has another pinion drive assembly provided with a pinion meshing with the second mentioned rack.

9. An apparatus as defined in any one of claims 1 to 8 wherein the base plate is provided with adjustable positioning bearings adapted to bear on the outer periphery ofthe container to position the container and spaced apart circumferentially of the container.

10. An apparatus for opening and closing hermetical containers substantially as described herein with reference to, and as illustrated in, Figures 1 to 7 or Figures 8 to 13 of the accompanying drawings.