The present invention relates generally to sterilizers, and more particularly, to a system for aligning doors on a steam sterilize.
Steam sterilizers are well known and widely used in hospitals, laboratories and other facilities for sterilizing and decontaminating many types of articles. Steam sterilizers define sterilization chambers that often operate under pressure or vacuum during a sterilization cycle. Access to the sterilization chamber is through an access opening at one end of the sterilizer. On some conventional steam sterilizers, access to the sterilization chamber is controlled by a door assembly that moves vertically relative to the access opening to the sterilization chamber. A seal typically surrounds the access opening and engages the inner surface of the door to form a seal around the access opening to the sterilization chamber. As indicated above, pressure within the chamber can exceed atmospheric pressure or may be below atmospheric pressure, thereby exerting forces against the inner surface of the door to force the door away from the sterilization chamber or to draw the door assembly toward the sterilization chamber.
Guiding systems are required to guide the door assembly relative to the access opening. Hooks or blocks are typically provided to prevent the door from moving significantly away from the sterilization chamber when the sterilization chamber is under high pressure. Heretofore, the door guiding mechanism was comprised of a linear guide/rail system that employed ball bearings or roller-bearing sliders that aligned the door for movement within a plane that spans the access opening. Such linear guide/rail systems require precision parts, aligned to facilitate movement of the door assembly in a single plane. In other words, guide/rail systems known heretofore do not allow movement of the door toward or away from the access opening to a sterilization chamber. This requires seal arrangements that can project outwards into engagement with the inner surface of the door to seal the sterilization chamber. In addition, such guide systems require precise alignment of the door to ensure proper sealing of the sterilization chamber.
The present invention provides a door alignment system that is simpler in design and cost, and allows limited movement of the door assembly toward and away from the access opening during sealing of the access opening and during operation of the sterilizer.
In accordance with the present invention, there is provided a steam sterilizer having a sterilization chamber and an opening for accessing the sterilization chamber. A door is movable relative to the opening between an open position and a closed position. A seal surrounds the opening. The seal is movable against the door when the door is in the closed position to seal the door relative to the sterilization chamber.
A plurality of spaced-apart roller assemblies are aligned along edges of the door to align the door relative to the opening as the door moves between an open and closed position. Each of the roller assemblies is comprised of a cylindrical roller having an outer annual recess extending along the periphery thereof. The recess is dimensioned to receive a lateral edge of the door. The roller is mounted on a shaft and is movable against a biasing force axially along the axis of the shaft, wherein the plurality of roller assemblies align the door and allow the door to move along a path in a plane and further allow limited movement of the door in a direction perpendicular to the plane.
An advantage of the present invention is a door alignment system for use on a steam sterilizer that allows the door to move across the access opening to the sterilizing chamber to open and close the same, the door alignment system allowing limited movement of the door, when in a closed position, toward and away from the access opening.
Another advantage of the present invention is a door alignment system as described above, that is simpler in design and allows the door assembly to adjust itself relative to the access opening when moving between an open position and a closed position.
Another advantage of the present invention is an alignment assembly as described above, wherein rollers engaging the lateral edges of the door assembly to guide the door between an open and closed position.
Another advantage of the present invention is an alignment system as described above, wherein the rollers allow movement of the door assembly in a direction perpendicular to the plane of the door assembly.
A still further advantage of the present invention is an alignment system as described above, wherein the rollers are mounted to a shaft and are biased axially along the shaft, wherein said rollers are movable along the shaft against the biasing forces.
Another advantage of the present invention is an alignment system as described above, wherein the rollers are movable with the door assembly relative to the access opening.
Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only and not for the purpose of limiting same:
Referring now the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting same,
Sterilizer 10 is basically comprised of a housing 12 enclosing an internal sterilization chamber 20. In the embodiment shown, housing 12 is generally rectangular in shape. Sterilizer chamber 20 is generally defined by a rectangular wall 22, a back end wall 24 and a front end wall 26. A rectangular opening 32 is formed in front end wall 26 to define an access opening to sterilization chamber 20 of sterilizer 10. As best seen in
A movable door assembly 50 is provided to open and close access opening 32 to sterilization chamber 20. Door assembly 50 is basically comprised of a flat plate 52 having an inner surface 52a dimensioned to cover access opening 32 to sterilization chamber 20.
In the embodiment shown, flanges 54 extend from the lateral sides of plate door 52 of assembly 50. Each flange 54 has a contoured, rounded edge surface 56 that extends along the length of the lateral sides of plate door 52 of assembly 50, as best seen in
Door assembly 50 is movable between a first position allowing access to sterilization chamber 20 and a second position closing access to sterilization chamber 20. In the embodiment shown, door assembly 50 is movable between a first, lowered position, as best seen in
Door assembly 50 may be moved by a number of different mechanical drive arrangements. In the embodiment shown, cables 62 attach to an upper portion of door assembly 50 on each side thereof. Each cable 62 is attached to a roller or spool 64 that is driven by a motor 66, as schematically illustrated in
As will be appreciated by those skilled in the art, other types of door transport mechanisms can be employed. For example, hydraulic or pneumatic cylinders may be used to move cables 62 over pulleys. Moreover, linear actuators driven by electric motors may also be used. Cables 62 may be counter-balanced by weights on the opposite ends of cables 62 to facilitate moving the door assembly. In this respect, the method of moving door assembly 50, in and of itself, forms no part of the present invention.
In accordance with one aspect of the present invention, a plurality of aligned roller assemblies 70 are provided along each edge of door assembly 50 to guide door assembly 50 between the first and second positions, i.e., between the open and closed positions. Roller assemblies 70 are best seen in
Roller assemblies 70 are mounted to mounting brackets 92 to operatively engage edges 56 of the door assemblies 50. Each roller assembly 70 is basically identical, and therefore only one shall be described in detail. Each roller assembly 70 is comprised of a roller 72 mounted to an elongated shaft 82 that in turn is secured to mounting bracket 92.
In the embodiment shown, shaft 82 is mounted to leg portion 92a of mounting bracket 92. In the embodiment shown, serrated, flange nuts 84 secure one end of shaft 82 to leg portion 92a of mounting bracket 92. Shaft 82 is oriented to be generally perpendicular to a plane in which door assembly 50 moves. Roller 72 includes an annular outer surface having a surface profile dimensioned to matingly engage and interact with an outer surface profile of lateral edge 56 of door assembly 50. In the embodiment shown, the surface profile is a concave, semi-cylindrical annular surface 74 that extends about the periphery of roller 72. Concave surface 74 defines annular side walls 76 along the peripheral edges of roller 72. As shown in the drawings, surface 74 defines a recess 78 is dimensioned to receive rounded, lateral edge 56 of door assembly 50 in mating fashion. Roller 72 is mounted on shaft 82 to be generally movable along axis of the shaft 82. Biasing elements 86 operatively engage both sides of roller 72 and exert a biasing force thereon in both directions along the axis of shaft 82.
In the embodiment shown, biasing elements 86 are comprised of helical springs that are disposed on opposite sides of roller 72 on shaft 82. Washers 88 are provided at the opposite ends of biasing element 86, i.e., the helical springs. A conventional fastener 89 at free end of shaft 82 confines roller 72 between biasing element 86 (helical springs).
A plurality of spaced-apart door blocks 112 are provided along each side of door assembly 50 in the recesses or notches 94 formed in mounting bracket 92, as best seen in
As best seen in
As best seen in
Referring now to
An inlet port 122 communicates with the backside of seal element 44. Inlet port 122 allows pressurized gas or steam from a source within sterilizer 10 to force seal element 44 against inner surface 52a of door assembly 50. (A more detailed explanation of the door seal arrangement can be found in the aforementioned U.S. Pat. No. 8,206,660). Introduction of pressure behind seal element 44 forces seal element 44 against inner surface 52a of door assembly 50, thereby forming a seal between door assembly 50 and sterilization chamber 20 from the surrounding environment. With sterilization chamber 20 sealed, a sterilization cycle may be run. Typically, steam would be introduced into the sterilization chamber via a steam inlet line 124, illustrated in
When pressure within sterilization chamber 20 exceeds the surrounding pressure, pressure exerted along inner surface 52a of the door assembly 50 and forces door assembly 50 away from the end face of sterilization chamber 20. This pressure forces door assembly 50 outward away from sterilization chamber 20. An outward facing surface 54a of flanges 54 of door assembly 50 abuts inward facing surface 116 of door block 112 and limits movement of door assembly 50 away from sterilization chamber 20. The back pressure behind seal element 44 causes seal element 44 to maintain sealing engagement with inner surface 52a of door assembly 50.
As illustrated in
When a vacuum condition exists within sterilization chamber 20 during a sterilization cycle, the vacuum exerts an inward force on inner surface 52a of door assembly 50 causing door assembly 50 to move toward front end wall 26 and causing inner surface 52a of door assembly 50 to abut the surface 26a of front end wall 26, as illustrated in
The foregoing description is a specific embodiment of the present invention. It should be appreciated that this embodiment is described only for the purposes of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention.
For example, the present invention has been described with roller 72 having an outer surface profile in the form of an annular recess 78 formed about the periphery of roller 72 to receive edge 56 of door assembly 50. In an alternate embodiment, the outer surface profile of edge 56 of door assembly 50 may be in the form of an elongated slot dimensioned to receive the edge of roller 72, wherein roller 72 rolls along in the slot.
Still further, the upper leading end of edge 56 is preferably tapered to facilitate entry into recess 78 of roller 72 as door assembly 50 moves from an opened position to a closed position.
It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof.
The present invention thus provides a door alignment system that allows limited movement of door assembly 50 in a direction perpendicular to the normal path of moving door assembly 50. The present invention thus eliminates more complex roller and bearing guides that do not easily allow movement transverse to the opening and closing direction of the door. The present invention provides a roller guide system that is easier and simpler than roller tract guide assembly known heretofore.
This is a Divisional of U.S. application Ser. No. 15/634,133, filed Jun. 27, 2017, and is hereby fully incorporated herein by reference.
Number | Name | Date | Kind |
---|---|---|---|
1554494 | Fleckenstein | Sep 1925 | A |
1985976 | Clark | Jan 1935 | A |
2541179 | Sponsler | Feb 1951 | A |
2755081 | Johnson | Jul 1956 | A |
2807836 | Knowles | Oct 1957 | A |
3144956 | Anderson | Aug 1964 | A |
3144957 | Anderson | Aug 1964 | A |
3386203 | Butler | Jun 1968 | A |
3413987 | Brown | Dec 1968 | A |
3959849 | Marquardt | Jun 1976 | A |
4048687 | Kato | Sep 1977 | A |
4403448 | Lesher | Sep 1983 | A |
4565031 | Sakamoto | Jan 1986 | A |
4708410 | Mazaki | Nov 1987 | A |
4872585 | Kim | Oct 1989 | A |
4880046 | Gesy | Nov 1989 | A |
4901474 | Bayard | Feb 1990 | A |
5148631 | Bayard | Sep 1992 | A |
5237777 | Houston | Aug 1993 | A |
5249392 | Houston | Oct 1993 | A |
5397138 | Mangelsdorf | Mar 1995 | A |
5535805 | Kellogg | Jul 1996 | A |
5543119 | Sutter | Aug 1996 | A |
5547453 | Di Perna | Aug 1996 | A |
5571488 | Beerstecher | Nov 1996 | A |
5723090 | Beerstecher | Mar 1998 | A |
5845363 | Brempell | Dec 1998 | A |
5863498 | Houston | Jan 1999 | A |
6017105 | Goughnour | Jan 2000 | A |
6264901 | Anderson | Jul 2001 | B1 |
6416144 | Houston | Jul 2002 | B1 |
6443148 | Rodocker | Sep 2002 | B1 |
6779567 | Szatmary | Aug 2004 | B1 |
6871448 | Kline | Mar 2005 | B1 |
6928696 | Wartman | Aug 2005 | B2 |
7121042 | Robert | Oct 2006 | B2 |
7124538 | Kline | Oct 2006 | B1 |
7361303 | Kantor | Apr 2008 | B2 |
8152027 | Baker | Apr 2012 | B1 |
8261941 | Woo | Sep 2012 | B2 |
8684065 | Peterson | Apr 2014 | B2 |
8745925 | Halfon | Jun 2014 | B2 |
9187941 | Therrien | Nov 2015 | B2 |
9242374 | Oaki | Jan 2016 | B2 |
9708844 | Glogowski | Jul 2017 | B2 |
20050132533 | Nguyen | Jun 2005 | A1 |
20080017649 | Elgan | Jan 2008 | A1 |
20100043172 | Nezu | Feb 2010 | A1 |
20110088327 | Meichtry | Apr 2011 | A1 |
20140163526 | Cabiri | Jun 2014 | A1 |
20150075077 | Aragon | Mar 2015 | A1 |
Number | Date | Country |
---|---|---|
WO-2012009022 | Jan 2012 | WO |
Number | Date | Country | |
---|---|---|---|
20220257808 A1 | Aug 2022 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 15634133 | Jun 2017 | US |
Child | 17737293 | US |