System for opening and closing a resealable cartridge

A system for opening and closing a resealable cartridge having a tray and a flexible cover resealably engaged with the tray. The system comprises: a base for receiving the tray of the cartridge; a roller shaft having means for engaging the cover of the cartridge; positioning means operably connected to the roller shaft to affect positioning of the roller shaft relative to the cartridge between a first position wherein the roller shaft is spaced from the cartridge and a second position different from the first position wherein the roller shaft is not spaced from the cartridge; and a motor for rotating the roller shaft in a first rotational direction to wind the cover about the roller shaft, thereby removing at least a portion of the cover from the tray, and for rotating the roller shaft in a second rotational direction to unwind the cover from the roller shaft thereby resealably engaging the cover with the tray.

FIELD OF THE INVENTION

The invention relates generally to resealable cartridges, and more particularly, to a system for opening and closing a resealable cartridge.

BACKGROUND OF THE INVENTION

Resealable cartridges have been employed in various applications for transporting articles. Such resealable cartridges are desirable features, including preventing exposure of the transported articles to environmental elements. For example, laser imaging machines use resealable cartridges to transport photosensitive media, such as x-ray and other types of medical imaging photographic film, since it is sometimes necessary to load a laser imaging machine with a different type or size of photosensitive media. Such laser imaging machines are well known in the art for forming an image by scanning a modulated laser beam across the photosensitive media. Prior to the formation of the image, a cartridge containing one or more photosensitive media is loaded into the laser imaging machine. The cartridge includes a tray having a supply area for containing the photosensitive media, a media access opening, and a flexible cover adhesively attached to tray to extend over the media access opening to form a light-tight seal of the cartridge. The light-tight seal enables the cartridge to be transported in light conditions that would otherwise cause exposure of the photosensitive media within the cartridge. U.S. Pat. No. 5,132,724 (Lemberger), U.S. Pat. No. 5,473,400 (Lemberger), and U.S. Pat. No. 5,480,134 (Weber) show examples of a resealable cartridge, each of these being incorporated herein by reference.

The interior of a laser imaging machine provides a light-tight environment. To carry out an imaging operation, the laser imaging machine withdraws one or more photosensitive media from the access opening of the cartridge. Therefore, the laser imaging machine requires a system that can open the cartridge within the laser imaging machine to allow withdrawal of the photosensitive media from the access opening, and close/reseal the cartridge within the laser imaging machine to effect the light-light seal. In the ordinary course of use, the cartridge must be opened and closed several times.

U.S. Pat. No. 5,132,724 (Lemberger) and U.S. Pat. No. 5,480,134 (Weber) show examples of mechanisms for opening and closing a resealable media cartridge. While such systems may have achieved certain degrees of success in their particular applications, they employ a relatively complicated mechanism that can be expensive to manufacture and have other disadvantages.

Accordingly, there is a need for a system which is capable of reliably performing the opening/closing functions, commercially viable, reduced in size, provides good resealing, and efficiently manufacturable.

The present invention provides a system for opening and closing a resealable cartridge which is capable of reliably performing the opening/closing functions, commercially viable, reduced in size, provides good resealing, and efficiently manufacturable.

In addition, wrinkles in the cartridge cover can occur while closing, and such wrinkles can decrease the usable life of the cartridge. In addition to wrinkles, laser imaging machines which use high sealing forces tend to displace the cover adhesive. The present invention increases the usable life of the cartridge by reducing/eliminating both wrinkles and displaced cover adhesive.

Additional features and advantages of the present invention will be set forth in part in the description that follows, and in part will be apparent from the description, or may be learned by practice of the invention. The advantages of the invention will be realized and attained by the system particularly pointed out in the written description and claims thereof, as well as in the appended drawings.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a system for opening and closing a resealable cartridge.

Another object of the present invention is to provide such a system which is capable of reliably performing the opening/closing functions.

A further object of the present invention is to provide such a system which is commercially viable, reduced in size, provides good resealing, and efficiently manufacturable.

According to one aspect of the invention, there is provided a system for opening and closing a resealable cartridge having a tray and a flexible cover resealably engaged with the tray. The system comprises: a base for receiving the tray of the cartridge; a roller shaft having means for engaging the cover of the cartridge; positioning means operably connected to the roller shaft to affect positioning of the roller shaft relative to the cartridge between a first position wherein the roller shaft is spaced from the cartridge and a second position different from the first position wherein the roller shaft is not spaced from the cartridge; and a motor for rotating the roller shaft in a first rotational direction to wind the cover about the roller shaft, thereby removing at least a portion of the cover from the tray, and for rotating the roller shaft in a second rotational direction to unwind the cover from the roller shaft thereby resealably engaging the cover with the tray.

DETAILED DESCRIPTION OF THE INVENTION

The following is a detailed description of the preferred embodiments of the invention, reference being made to the drawings in which the same reference numerals identify the same elements of structure in each of the several figures.

FIG. 1shows an exemplary laser imaging machine10configured for use with a resealable cartridge, and suitable for incorporation of an opening and closing system in accordance with the present invention. Machine10can include a hinged loading door14into which a resealable cartridge can be loaded for imaging operations. Other suitable laser imaging machines can employ a loading drawer that slides out to receive the cartridge. Other loading arrangements may be known to those skilled in the art.

The cartridge opening/closing system of the present invention is mounted within laser imaging machine10. After the cartridge has been loaded within laser imaging machine10, the door/drawer is closed to seal the cartridge within the light-tight environment of laser imaging machine10. The opening/closing system then operates to open the cartridge to permit access to the photosensitive media in the cartridge. The photosensitive media is withdrawn from the opened cartridge by imaging hardware associated with machine10. The media is then imaged by other subsystems of laser imaging machine10. The opening/closing system is also actuated to close the cartridge before the cartridge is removed from laser imaging machine10. Since the cartridge is resealable, it can be removed from machine10before all the photosensitive media within the cartridge has been exposed. Cartridges with different sizes or types of media can therefore be conveniently loaded/reloaded into and removed from laser imaging machine10as needed, and without wasting any unused media remaining within the cartridge.

Laser imaging machine10may include more than one drawer so that more than one cartridge can be loaded into machine10. This may be desirable if the cartridges contain photosensitive media of different sizes. As such, it is noted that the opening/closing system needs to be configured to operate with cartridges containing photosensitive media of different sizes.

An exemplary resealable cartridge12is described with reference toFIGS. 2 through 4. Other configurations may be known to those skilled in the art. Since resealable cartridges are well-known, the cartridge will not be discussed in detail.

Cartridge12includes an optically opaque media-receiving tray20and a flexible, optically opaque cover22. The flexible cover22can be resealably mounted to tray20by an adhesive material24, by means of magnetics, or other method known to those skilled in the art. For ease of explanation of the present invention, cover22is mounted by means of adhesive24. Tray20can be molded in one piece from a photo-inert, polyolefin material. Tray20includes a bottom wall26, a front wall28A, a rear wall28B, opposite side walls28C,28D, and a lip having sections30A-30D extending outward from upper edges of walls28A-28D, respectively, around a periphery of the tray. Adhesive material24may take the form of segments of adhesive disposed at intervals along lip sections30A-30D, or a one-piece adhesive gasket applied to the lip. Side walls28A-28D and lip sections30A-30D define an access opening. For laser imaging, the access opening may contain one or more photosensitive media31, as shown inFIG. 2. Photosensitive media31may comprise, for example, x-ray film, photosensitive film, photosensitive paper, or other photosensitive substrate materials for imaging applications.

Tray20includes inward projecting guides32formed on walls28A-28D for properly positioning photosensitive media31. Feet34A-34D are formed into and extend downward from bottom wall26to support cartridge12within base18of the opening and closing mechanism in accordance with the present invention. A media presence monitoring well35also is formed in bottom wall26. A media presence monitoring sensor associated with laser imaging machine10extends into well35below the surface of bottom wall26when all media have been removed from tray20, thereby detecting that tray20is empty. Bottom wall26further includes positioning recesses36, molded into feet34A and34B, that extend upward into tray20from the exterior surface of the bottom wall.

Feet34A,34B formed adjacent front wall28A include ramp surfaces38that slope downward from the lower edge of the front wall, as shown inFIG. 4. Ramp surfaces38can be employed to guide feet34A,34B over optional locator pins formed in base18when cartridge12is loaded into the base. Tray20further includes a recessed area40formed in bottom wall26that provides a platform on the exterior surface of the bottom wall. The platform formed by recessed area40can carry bar code indicia for identifying the type of media contained in cartridge12.

With reference toFIGS. 2 and 3, a series of evenly spaced cut-out sections42are formed in lip section30A over the top edge of front wall28A. Cut-out sections42define a series of spaced projections44on lip section30A. A forward area45of cover22includes a series of elongated apertures46aligned with cut-out sections42of tray20when the cover is disposed over the tray. The cut-out sections42cooperate with apertures46to facilitate engagement of cover22by the opening and closing mechanism of the present invention.

Cover22is preferably a flexible, photo-inert and optically opaque sheet of material sized to extend over the media access opening of tray20and mate with lip sections30A-30D. The cover22comprises a material that is preferably stretchable enough to avoid pulling away from tray20when cartridge12is flexed, but rigid enough to resist excessive stretching during opening and closing operations. Cover22may also include a reinforcing strip (not shown) at a forward area45to increase the rigidity of the cover in the area above cut-out sections42of tray20. The reinforcing strip is intended to resist tearing of apertures46during engagement with the opening and closing mechanism. The stretch-resistant material and reinforcing strip of cover22are designed to resist the damage caused by certain forces applied to the cover during the opening and closing operations, and thus address the effects of such forces in an effort to extend cartridge life.

The opening and closing system of the present invention is intended to reduce/eliminate the application of the forces responsible for stretching cover22and tearing apertures46, thereby addressing the source of such problems. An exemplary embodiment of the opening and closing mechanism of the present invention will now be described in detail with reference toFIGS. 5-17.

Referring first toFIGS. 5-8, an opening and closing system50includes a base52for receiving and supporting resealable cartridge12, a roller shaft54including means for engaging cover22, a motor56for rotating roller shaft54, and a carriage58, slidably coupled to base52, for supporting roller shaft54and motor56. Carriage58can be mounted on drawer slides.

Generally, the purpose of opening and closing system50is to open and close cover22of cartridge12. Roller shaft54rotates and spins along the front edge cartridge12until projections/teeth on roller shaft54engage apertures46in cover22. Once engaged, roller shaft54rolls up onto the front and back walls of cartridge12(moving along the length of cartridge12in the direction shown by arrow A inFIG. 5), thereby wrapping cover22around/about the diameter of roller shaft54. As the motorized roller shaft turns, it moves towards the center of cartridge12until cover22is open sufficiently to allow a mechanism or other device to remove the media from cartridge12. Operating roller shaft54in the opposite direction reseals cartridge12.

More particularly, a rotation of roller shaft54in the first (opening) direction generates tractional force between roller shaft54and cartridge12. A bias means applies a normal force that biases roller shaft54downward against cartridge12. The carriage includes means for supporting roller shaft54and motor56, as will be described. The tractional force results in a translational force that drives the carriage to slide along tray20. A tractional force generated between roller shaft54and cover22during the closing operation similarly provides a translational force that drives the carriage to slide.

Roller shaft54is an elongated member, and can be formed of steel. A cut-out, winding section78, extending along a central longitudinal axis, includes means for engaging apertures46in cover22to open and close cartridge12. As shown inFIG. 6, winding section78has a substantially semi-circular cross-section. In the embodiment shown, the cover engaging means of roller shaft54comprises an elongated, rectangular plate80having a plurality of indentations82defining curved, tooth-like projections84. Projections84preferably are sized and spaced to fit within apertures46of cover22, as well as cut-out sections42, when roller shaft54is rotated downward toward base18. Plate80and projections84may be constructed by stamping them out of a piece of sheet metal, and fastening them with screws86to a portion of winding section78that has been cut down to approximately a half diameter. The radius of curvature of projections84can be achieved by bending the plate80about a metal form.

A spring assembly60is disposed at each end of roller shaft54to provide a sealing force. As best shown inFIG. 8, spring assembly60includes a pinch roller62attached to a bracket64that pivots about a shaft66attached to a roller link68. A torsion spring70provides a torque to apply a suitable sealing force. In one embodiment of the present invention, a torque of 0.66 inch-pounds has been found to apply a suitable sealing force of 1.4 pounds.

Also disposed at each end of roller shaft54is a cam72which controls the motion of roller shaft54and provides indexing of roller shaft54during engagement with cover22. A pair of torsion springs74disposed at each end of roller shaft54direct roller shaft54along a cam surface76of a pair of cam nests77, as will be more particularly described below. Pivot mechanism75links torsion springs74with roller shaft54. Motor56can be a single dc motor.

High roller pressure and wrinkles in cover20can limit the usable life of cartridge12. High roller pressure displaces the cover adhesive, resulting in poor sealing characteristics, when the cartridge is open for extended periods (for example, overnight). Wrinkles occur when opening and closing system50is closing cartridge12.FIGS. 9aand9billustrate a factor that leads to wrinkles.FIG. 9ashows roller shaft54operating (moving in opening direction D) to open cover22wherein a portion79′ of cover22does not conform roller shaft54.FIG. 9bshows roller shaft54during the subsequent closing operation (moving in closing direction E) wherein the non-conforming portion79′ of cover22forms on the cartridge as a wrinkle79″.

It was determined that adding a force in the closing direction (i.e., during the closing operation) keeps cover22tight/taught against roller shaft54, thereby eliminating non-conforming cover portions and hence the wrinkles. Referring toFIG. 10, a pair of constant force springs81supplies a force sufficient to eliminate the wrinkles without pulling cover22closed. The constant force springs pull carriage12toward a frame83in the closing direction. This addition force eliminates the need for a high sealing force (high forces have been used on previous opening and closing systems), and eliminates the adhesive displacement. A force of 0.50 pounds for each constant force spring (1.00 pounds total) has been found to be suitable.

Referring now toFIG. 11, in operation, loading drawer/door14is opened and cartridge12is loaded into laser imaging machine10by sliding cartridge12onto base52in a direction shown by arrow B. One or more slides85can be employed to promote the loading/unloading of cartridge12in drawer/door14. Note the positioning of opening and closing50relative to the direction of loading of cartridge12. That is, cartridge12is loaded in a direction toward opening and closing system50. As such, a user is not exposed to projections84when loading.

FIG. 11provides an alternative loading arrangement. In this arrangement, cartridge12is loaded into laser imaging machine10by sliding cartridge12onto base52in a direction shown by arrow C along slide85. With this loading arrangement, cartridge12is loaded in a direction along (i.e., parallel to) the axis of roller shaft54. Opening and closing system50is disposed such that it does not interfere with the loading of cartridge12.

One or more sensors can be employed to verify the cartridge condition (e.g., presence, absence, and/or proper orientation) of cartridge12within laser imaging machine10. These sensors can be mechanical or electrical sensors, as is well known to those skilled in the art. For example, referring toFIG. 12, three sensors can be employed S1, S2, S3, with the sensors being mechanical members. With three sensors, three situations can be determined: the absence of the cartridge, the correct placement of the cartridge, and the incorrect placement of the cartridge. The situation can be determined by the state of each sensor. For example, the following can be determined:

Referring again toFIG. 11, one sensor S4is employed to verify the presence and/or proper orientation of cartridge12. With the arrangement ofFIG. 11, the following cartridge conditions can be determined:

Opening and closing system50can operate using one dc motor (i.e., motor56) and two position sensors.FIGS. 13-17illustrate the operation of opening and closing system50to open and close cartridge12.

FIG. 13shows a partial side view of opening and closing system50in a first position, referred to as the home position. This is the position of opening and closing system50when cartridge12is loaded in laser imaging machine10. In this position, the components of system50are not disposed within the loading area of cartridge12. In this position, cams72actuate a sensor88indicating that roller shaft54is in the home position. In this position, roller shaft54is disposed away from the perforated edge89of cover22, and projections84are disposed downward, toward base52.

FIG. 14shows a partial side view of opening and closing system50in a second position, referred to as the cam lift position. In this position, each cam72interfaces with a surface on cam nest77to lift/raise roller shaft54towards perforated edge89of cover22.

FIG. 15shows a partial side view of opening and closing system50in a third position, referred to as the cam dwell position. In this position, each cam72interfaces with a surface on cam nest77in a dwell state.

FIG. 16shows a partial side view of opening and closing system50in a fourth position, referred to as the cover engaged position. In this position, roller shaft54continues to rotate and projections84engage apertures46of cover22.

FIG. 17shows a partial side view of opening and closing system50in a fifth position, referred to as the open position. In this position, an end-of-travel sensor91is blocked to indicate the end of the travel for opening and closing system50.