Patent Publication Number: US-2022227589-A1

Title: Pneumatic tube system with secure carrier storage

Description:
PRIORITY CLAIM 
     The present disclosure claims priority to U.S. Provisional Patent Application Ser. No. 63/199,709 filed Jan. 19, 2021; the disclosure of which is incorporated herewith by reference. 
    
    
     BACKGROUND 
     Pneumatic tube systems transport various items through buildings or groups of buildings such as, for example, moving drugs, lab specimens and blood products to various locations throughout a hospital. All items delivered by a hospital pneumatic tube system must be handled with care and safeguarded given their role in patient care. However, certain deliveries either require or benefit from additional security, tracking and control. Existing pneumatic tube systems used to safeguard high-value items, or for otherwise holding inbound and outbound carriers when other resources are busy, can decrease efficiency and increase complexity of the system. 
     SUMMARY 
     The present disclosure relates to a carrier vault for a workstation of a pneumatic tube system. The carrier vault comprises a rotatable carousel comprising at least a first and second carrier port, each carrier port sized and shaped to hold a carrier used to transport materials via the pneumatic tube system and to allow the carrier to pass through the carousel, the carousel being configured to rotate between a first position, where the first carrier port is aligned with an access tube of the pneumatic tube system, and a second position, where the second carrier port is aligned with the access tube. The carrier vault further comprises a selection gate adjacent to the carousel comprising a rotatable plate and a selection gate opening, the selection gate being configured to rotate between an open position, where the selection gate opening is aligned with the access tube and the carrier is allowed to pass through the plate, and a closed position, where the selection gate opening is not aligned with the access tube and the carrier is prevented from passing through the plate. When an arriving carrier is to be stored in the carrier vault, the carousel is rotated to or maintained in the first position and the selection gate is rotated into or maintained in the closed position to receive the arriving carrier in the first carrier port. When the arriving carrier is received in the first carrier port, the carousel is rotated to the second position and the selection gate is rotated into the open position so that the arriving carrier is stored in the carrier vault and the workstation remains available for subsequent carrier transmissions through the second carrier port. 
     The present disclosure also relates to a pneumatic tube system comprising a workstation configured to send and receive carriers via the pneumatic tube system, a carrier vault for the workstation located separately from the workstation in the pneumatic tube system, the carrier vault comprising at least one carrier port for holding carriers and a port for servicing the workstation, and a system blower configured to place an arriving carrier for the workstation into the carrier port. 
     The present disclosure also relates to a storage device of a pneumatic tube system. The storage device comprises a rotatable carousel comprising at least a first tube and a second tube, each tube sized and shaped to permit passage of a carrier used to transport materials via the pneumatic tube system, the carousel being configured to rotate between a first position, where the first tube is aligned with an access tube of the pneumatic tube system, and a second position, where the second tube is aligned with the access tube. The storage device further comprises a stop plate adjacent to the carousel comprising an open tube stub and at least one closed tube stub, the stop plate being configured to rotate between an open position, where the open tube stub is aligned with the access tube and the carrier is allowed to pass through the stop plate, and a closed position, where the closed tube stub is aligned with the access tube and the carrier is prevented from passing through the stop plate. When an arriving carrier is to be stored in the storage device, the carousel is rotated to or maintained in the second position and the stop plate is rotated into or maintained in the closed position to receive the arriving carrier in the second tube. When the arriving carrier is received in the second tube, the carousel is rotated to the first position and the stop plate is rotated into the open position so that the arriving carrier is stored in the storage device and the workstation remains available for subsequent carrier transmissions through the first tube. 
    
    
     
       BRIEF DESCRIPTION 
         FIGS. 1 a - b    show an exemplary pneumatic tube workstation for a pneumatic tube system including a secure vault for securely holding multiple carriers prior to retrieval by authorized personnel, according to various exemplary embodiments described herein. 
         FIGS. 2 a - b    show perspective views of the secure vault of  FIGS. 1 a   - b.    
         FIG. 2 c    shows a front view of the secure vault of  FIGS. 1 a   - b.    
         FIG. 2 d    shows a side view of the secure vault of  FIGS. 1 a   - b.    
         FIG. 2 e    shows a top view of the secure vault of  FIGS. 1 a - b    in the default position. 
         FIG. 2 f    shows a top view of the secure vault of  FIGS. 1 a - b    in a first catch position. 
         FIG. 2 g    shows a top view of the secure vault of  FIGS. 1 a - b    in the default position with a first high-value carrier stored in the secure vault. 
         FIG. 2 h    shows a top view of the secure vault of  FIGS. 1 a - b    in a second catch position. 
         FIG. 2 i    shows a top view of the secure vault of  FIGS. 1 a - b    in the default position with the first high-value carrier and a second high-value carrier stored in the secure vault. 
         FIG. 2 j    shows a top view of the secure vault of  FIGS. 1 a - b    in a release position for delivering the second high-value carrier to the arrival bin. 
         FIGS. 3 a - c    shows the exemplary carousel of the previous Figures including a latch for attaching the selection gate to the platform of the carousel. 
         FIGS. 4 a - b    show a Geneva mechanism for rotating the carousel. 
         FIG. 5  shows a pneumatic tube system for the workstation comprising the secure carrier vault of the previous Figures. 
         FIG. 6  shows a pneumatic tube system  300  comprising a diverter with storage stubs for use as a secure carrier vault. 
         FIG. 7  shows a pneumatic tube system comprising a dedicated compact blower and a diverter with storage stubs for use as a secure carrier vault. 
         FIG. 8  shows a pneumatic tube system comprising a horizontal storage device for use as a secure carrier vault. 
         FIGS. 9 a - c    show views of an exemplary storage device for use as a carrier vault separate from a workstation in a pneumatic tube system. 
         FIGS. 9 d - f    show cross-sectional views of the storage device of  FIGS. 9 a   - c.    
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure may be further understood with reference to the following description and the appended drawings, wherein like elements are referred to with the same reference numerals. The present disclosure is directed to systems and methods for securely and efficiently delivering items via a pneumatic tube system. In some exemplary embodiments, a workstation for the pneumatic tube system includes a secure vault for storing carriers prior to delivery to authorized personnel. In other exemplary embodiments, the secure vault can be located upstream from the destination workstation and the pneumatic tube system can include shared or dedicated components, e.g., diverters and/or blowers, to place a carrier in the vault, extract the carrier from the vault, and/or deliver the carrier to the workstation. 
     Pneumatic tube systems are used to transport items throughout various facilities. For example, pneumatic tube systems are often used to transport drugs, lab specimens, blood products and other items throughout hospitals and other healthcare facilities. For example, for a typical midsize hospital with, e.g., 300 patient beds, more than 1,200 medical items may be delivered each day via a pneumatic tube system. All items delivered by a hospital pneumatic tube system should be safeguarded given their role in patient care. However, certain deliveries of “high value” items, such as items that are difficult to replace (e.g., tissue samples and blood products), expensive items (e.g., cancer drugs), or controlled substances (e.g., narcotics), either require or benefit from additional security, tracking and control. 
     Historically, high-value items are either delivered by hand (what clinicians refer to as “walked”) or transported by pneumatic tube either without additional precautions or with added steps that increase security at the expense of speed, reliability, and ease of use. Walking an item adds considerable time to a delivery and may additionally take a highly paid and skilled clinician away from their core patient-centric tasks. Walking also adds to the workload of elevators, reducing their availability to patients, staff and visitors. 
     Transporting high-value items by pneumatic tube without additional precautions is often undesirable and may even violate Federal and State regulations. Even when regulations are not a factor, unprotected deliveries increase the chance that high-value items will be misplaced or retrieved by unauthorized recipients. For example, a misplaced tissue sample may put a patient&#39;s safety at risk and/or cause undue suffering when a second sample must be obtained. In another example, a misplaced cancer drug may delay treatment and incur significant expense. In still another example, a controlled substance that is misdelivered can increase the risk that the substance will be misused, perhaps in a dangerous manner. Safety can be improved when security steps are added, but these steps are often cumbersome and may decrease efficiency and increase the complexity of the delivery process. In a hospital, few things are as valuable as a clinician&#39;s time, and anything that adds to the workload of a clinician takes them away from patient-centric tasks, and by extension, adversely impacts patient care. Similarly, any equipment and/or procedures that are complex increase the chance for error and may degrade care. 
     The features in use today to improve the security of high-value items transported by pneumatic tube system generally suffer from various shortcomings. One common approach holds a high-value item and its carrier above a receiving station on said station&#39;s slide-plate until an authorized recipient identifies himself (e.g., by entering a release-code, scanning an ID badge, etc.). Although this approach is potentially secure (depending on the implementation details), until the carrier is retrieved (i.e., while the carrier is held on the slide plate), the receiving station is not available for deliveries or the sending out of departing carriers, which may result in cascading system-wide delays. 
     Approaches requiring a clinician to scan an ID badge to trigger release of the carrier may not limit release to only an intended recipient of the carrier (e.g., a scan of any ID badge may be permitted to release the carrier). If the high-value item in the carrier is, for example, a narcotic, the non-targeted recipient may be tempted to misuse the contents. If the item is a high-value drug or blood product, the item is at risk of being misplaced before the intended recipient takes possession. If, to enhance security, the release of the carrier is permitted only when an authorized recipient identifies himself as present at the station (i.e., only the scan of a single ID or one of a defined group triggers release of the carrier), the time that the receiving station is offline is further increased as other users that may arrive at the station before the authorized recipient(s) cannot retrieve the carrier. If no authorized person is available (e.g., is on break or with a patient), the wait may be lengthy. 
     In another existing approach, the station itself can hold carriers in secure locations while remaining open to a limited number of other carrier departures and arrivals. These stations are mechanically complex and costly, making them impractical for most new construction and retrofit applications. Those skilled in the art recognize that pneumatic tube workstations must be reliable with near 100% uptime and require minimal maintenance. Stations that require multiple motors, sensors and datasets to work in unison are often unreliable. Known multi-purpose stations generally hold no more than four carriers that are either waiting to depart or waiting to be retrieved. Once full, the stations go offline causing system-wide congestion. And once a carrier has been placed inside the station, the sending clinician has no way to know how long the carrier will wait before departure since these stations generally have only a single in/out tube port. The ideal solution, as described herein, stores multiple inbound high-value carriers and their cargo securely while keeping the station open for regular arrivals and departures. 
     According to various exemplary embodiments described herein, a secure carrier vault is implemented at a pneumatic tube workstation and is configured for holding one or more carriers prior to retrieval by authorized personnel. The exemplary secure vault is reliable, mechanically simple, easy to use and affordable, while requiring only traditional preventive maintenance. 
     The exemplary secure vault is configured as a self-contained electromechanical box that can be used in new workstations as well as in retrofit upgrades to existing workstations. The secure vault is further configured to keep the workstation online nearly 100% of the time by moving certain carriers (e.g., high value carriers) away from an access port for the workstation, allowing standard carriers to be sent and received at the workstation while the high value carriers remain securely stored. The secure vault according to an exemplary embodiment relies on gravity to drop the carrier, keeping blowers and other system resources available for system use. Alternative embodiments employ blowers to move the carriers from secure locations to the location from which they may be accessed by recipients. Additionally, the secure vault according to one embodiment positively identifies personnel authorized to receive the carrier so that the carrier may be released only when the presence of an authorized recipient is established. 
     In the following, the carriers received at the workstation may be referred to as “high-value” carriers or “standard” carriers. The high value carrier refers to a carrier that is subject to some form of additional security, tracking or control and that is required to be received by an authorized user, while the standard carrier is not subject to additional controls and may be passed to the access bin of the workstation without any additional authorization measures. The type of carrier, e.g., standard or high value, can be indicated by the sender of the carrier and subsequently tracked by the pneumatic tube system so that the carrier is processed in accordance with the type. The high value carriers can be additionally identified by the sender so that only certain individuals are authorized to receive the particular carrier, e.g., one specific person, a group of people (e.g., nurses), etc. Although the following embodiments are described with respect to the storing of high value carriers, it should be understood that any carrier can be stored in the secure vault for any reason, for example, when the arrival bin is full, as will be described in further detail below. 
       FIGS. 1 a - b    show an exemplary pneumatic tube workstation  100  for a pneumatic tube system including a secure vault  102  for securely holding multiple carriers  104  prior to retrieval by authorized personnel, according to various exemplary embodiments described herein.  FIG. 1 a    shows a front view of the exemplary workstation  100  and  FIG. 1 b    shows a side view of the exemplary workstation  100 . The secure vault  102  incorporates a rotatable carousel  114  with multiple carrier ports  116  for holding one or more high value carriers  104   h , to be described in further detail below with respect to  FIG. 2 a   - g.    
     The workstation  100  includes an access port  106  extending from the top of the secure vault  102 . The access port  106  is sized and shaped to connect to the pneumatic tubing  108  of the pneumatic tube system, e.g., the main arrival/departure system access tube  108 . For example, the pneumatic tubing  108  and the access port  106  may have a diameter of 4″ or 6″. However, those skilled in the art will recognize that the components of the workstation  100  may be sized to support any size of tubing. 
     The workstation  100  further includes a carrier arrival bin  110  for receiving the carriers  104  that are dropped down from the pneumatic tube  108  (via the secure vault  102 ) prior to retrieval by personnel. The arrival bin  110  is sized to hold a number of carriers prior to retrieval. The workstation  100  also includes a slide gate (not shown) that can be retracted to allow the carriers to drop into the arrival bin  110 . In the example of  FIGS. 1 a - b   , the workstation  100  has two legs  112  attached to the sides of the arrival bin  110  for supporting the workstation  100  from the floor at a height that is convenient for use by personnel. However, those skilled in the art will recognize that the workstation  100  can be supported in alternative ways, for example by mounting the workstation  100  to a wall using suitable mechanical fastenings, or using four feet extending from the bottom of the arrival bin  110  to support the workstation when the workstation  100  is installed on, e.g., a countertop. 
       FIGS. 2 a - g    show the secure vault  102  of the workstation  100  of  FIGS. 1 a - b    according to various exemplary embodiments described herein.  FIGS. 2 a - b    show perspective views of the secure vault  102 ;  FIG. 2 c    shows a front view of the secure vault  102 ;  FIG. 2 d    shows a side view of the secure vault  102 ;  FIG. 2 e    shows a top view of the secure vault  102  in the default position;  FIG. 2 f    shows a top view of the secure vault  102  in a first catch position;  FIG. 2 g    shows a top view of the secure vault  102  in the default position with a first high-value carrier  104   h  stored in the secure vault  102 ;  FIG. 2 h    shows a top view of the secure vault  102  in a second catch position;  FIG. 2 i    shows a top view of the secure vault  102  in the default position with the first high-value carrier  104   h  and a second high-value carrier  104   h  stored in the secure vault  102 ;  FIG. 2 j    shows a top view of the secure vault  102  in a release position for delivering the second high-value carrier  104   h  to the arrival bin  110 . 
     The secure vault  102  incorporates a carousel  114  with multiple carrier ports  116  (in this example, three (3) vertical carrier ports  116   a ,  116   b  and  116   c  although those skilled in the art will understand that any number of carrier ports may be included depending on considerations of space, etc.) coupled to a platform  118 . A first one of the carrier ports  116 , which in this example corresponds to carrier port  116   a , is open for receiving deliveries of standard carriers  104  and for sending carriers  104  out from the workstation  100 . Thus, the carrier port  116   a  is aligned with the access tube  108  (at the top of the carrier port  116   a ) and an opening into the arrival bin  110  (at the bottom of the carrier port  116   a ). The remaining carrier ports  116   b  and  116   c  are available to hold arriving high-value carriers  104   h  in the secure vault  102  until retrieved by an authorized recipient. Each carrier port  116  is formed as a tube segment having a diameter and length selected to be sufficient to hold a carrier  104  therein, in accordance with the specifications of the pneumatic tube system carrying the carriers  104 . 
     The carousel  114  is rotatable between three positions: 1) a first position in which the carrier port  116   a  is aligned with the access port  106  and the main arrival/departure system access tube  108 , as shown in  FIG. 2   e;  2) a second position in which carrier port  116   b  is aligned with the access port  106  and the main arrival/departure system access tube  108 , as shown in  FIG. 2 f   ; and 3) a third position in which carrier port  116   c  is aligned with the access port  106  and the main arrival/departure system access tube  108 , as shown in  FIG. 2 h   . In a default position, the carousel  114  is rotated so that one of the carrier ports  116  (e.g., carrier port  116   a ) is aligned with the main arrival/departure system access tube  108  of the workstation  100 . This default position allows the workstation  100  to operate in its most efficient manner (e.g., permitting standard carriers  104  to pass through the carrier port  116   a  for delivery to the station) since the vast majority of arrivals are standard carriers  104  and not high-value carriers  104   h.    
     The platform  118  includes three openings aligned with the bottom openings of the carrier ports  116 . A plate referred to as a selection gate  120  is rotatably mounted beneath the platform  118  and includes a single opening  122 . The selection gate  120  of this embodiment has two modes of operation: a first mode where the selection gate  120  is fixed to the carousel  114  and rotatable therewith when the carousel  114  is rotated; and a second mode where the selection gate  120  is stationary and non-rotatable even when the carousel  114  is rotated. The selection gate  120  and the carousel  114  of this embodiment can be fastened together using a latch  124  mounted on the selection gate  120 , to be described in greater detail below with respect to  FIGS. 3 a - c   . When the selection gate  120  and the carousel  114  are attached, a rotation force applied to the carousel  114  by, e.g., a motor, to be described below in  FIGS. 4 a - b   , will cause the selection gate  120  to rotate along with the carousel  114 . When the selection gate  120  and the carousel  114  are detached, the selection gate  120  remains stationary while the carousel  114  rotates. 
     The selection gate  120  includes the opening  122  that allows the carriers  104  to pass between the carrier ports  116  and the arrival bin  110  when a given carrier port  116  is aligned with the opening  122 . When the selection gate  120  is in the open position, the selection gate  120  is in axial alignment with the main arrival/departure system access tube  108  and with the carrier port  116  in the same current alignment, which in this example is carrier port  116   a , as shown in  FIG. 2 e   . When the selection gate  120  is in the closed position, the selection gate  120  is out of axial alignment with the main arrival/departure system access tube  108  and with the carrier port  116  in the same alignment as the access tube  108 , such as, for example, the carrier port  116   c  in  FIG. 2 f    and the carrier port  116   b  in  FIG. 2 h   , thus, preventing a carrier  104  received in the carrier port  116  from entering the arrival bin  110 . Thus, when a high value carrier  104   h  is arriving to the workstation  100 , the selection gate  120  is rotated to the closed position to prevent the high value carrier  104   h  from dropping into the arrival bin  110 . A default position for the selection gate  120  is the open position so that if, for example, the carrier port  116   a  is currently aligned with the main arrival/departure system access tube  108  and a standard carrier  104  arrives to the workstation  100 , this arriving carrier  104  drops into the arrival bin  110  without being stored in the secure vault  102 . Additionally, when the selection gate  120  is in the open position, personnel can use the main arrival/departure system access tube  108  to send out carriers as the carrier port  116   a  provides an open connection to the main arrival/departure system access tube  108 . 
       FIGS. 2 e - j    show an exemplary series of operations for storing high value carriers  116   h  in the secure vault  102 . In  FIG. 2 e   , the carrier port  116   a  and the selection gate  120  are in the open position. A standard carrier  104  is shown passing through the carrier port  116   a  and the opening  122  in the selection gate  120 . As described above, in the open position, the workstation  100  can be used in normal operation to receive any number of standard carriers  104  and send any number of the carriers  104 , including standard carriers  104  and high value carriers  104   e.    
     A system software executed by a processor (not shown) may be notified that a high value carrier  104   h  is imminently arriving at the workstation  100  while the carrier port  116   a  and the selection gate  120  are in the open position. To receive and securely store the high value carrier  104   h , in a first step, the carousel  114  and the selection gate  120  are fastened and rotated in a first direction (in this example, counter-clockwise), bringing the carrier port  116   a  and the opening  122  of the selection gate  120  out of alignment with the arrival/departure access tube  108  and bringing the carrier port  116   c  into alignment with the arrival/departure access tube  108 . This position may be considered a “catch” position for the carrier port  116   c , wherein the selection gate  120  is in the closed position for the carrier port  116   c  while the carrier port  116   c  is positioned to receive a carrier  104  from the access tube  108 , as shown in  FIG. 2   f.    
     The high value carrier  104   h  is then received in the carrier port  116   c . Those skilled in the art will also understand that, when the selection gate  120  extends across the bottom of the carrier port  116  currently rotated into alignment with the main arrival/departure system access tube  108 , the selection gate  120  of this embodiment may optionally form a substantially airtight seal with the bottom of the carrier port  116  so that air trapped in this carrier port  116  forms a cushion that slows down the high value carrier  104   h  as it enters the carrier port  116  so that the carrier  104   h  does not impact the selection gate  120  forcefully. 
     The carousel  114  and the selection gate  120  remain fastened, and, in a second step, are rotated in the reverse direction (in this example, clockwise) and back into the open position for the carrier port  116   a , as shown in  FIG. 2 g   . The high value carrier  104   h  is accordingly rotated into the secure vault  102  to await retrieval from authorized personnel. As before, the workstation  100  can be used in normal operation. 
     The system software may be notified that a second high value carrier  104   h  is imminently arriving at the workstation  100  while the carrier port  116   a  and the selection gate  120  are in the open position and while the carrier port  116   c  is holding the first high value carrier  104   h . To receive and securely store the second high value carrier  104   h , in a third step, the carousel  114  and the selection gate  120  remain fastened and are rotated in a second direction (in this example, clockwise), bringing the carrier port  116   a  and the opening  122  of the selection gate  120  out of alignment with the arrival/departure access tube  108  and bringing the carrier port  116   b  into alignment with the arrival/departure access tube  108 . This position may be considered the “catch” position for the carrier port  116   b , wherein the selection gate  120  is in the closed position for the carrier port  116   b , as shown in  FIG. 2   h.    
     The high value carrier  104   h  is then received in the carrier port  116   b . The carousel  114  and the selection gate  120  remain fastened, and, in a fourth step, are rotated in the reverse direction (in this example, counter-clockwise) and back into the open position for the carrier port  116   a , as shown in  FIG. 2 i   . The high value carrier  104   h  is rotated into the secure vault  102  to await retrieval from authorized personnel. In this current operation state the two carrier vaults  114   b ,  114   c  are both holding high value carriers  104   h , thus, the exemplary secure vault  102  cannot receive any more high value carriers  104   h . If two high value carriers  104   h  are already being held at a workstation  100  including three carrier ports  116 , the software instructs the system to prevent the sending of any additional high value carriers  104   h  to this workstation  100  until one of the already received high value carriers  104   h  has been cleared from the secure vault  102 . This permits the workstation  100  to continue to send out carriers  104  and to receive standard carriers  104 . Thus, as before, the workstation  100  can be used in normal operation. Based on usage statistics gathered from hundreds of hospitals, two (2) storage ports are sufficient to accommodate high-value item deliveries 99.99% of the time. 
     The system software for the pneumatic tubing system and/or the workstation  100  can be adapted to notify the intended recipient(s) of the delivery of a high value carrier  104   h  to the workstation  100  and, once notified, the recipient will be required to provide secure identification at the workstation  100  to authorize the secure vault  102  to dispense the correct high value carrier  104   h  to the authorized recipient. Once authorized, and with no scheduled incoming carriers to the workstation  100 , the system software will temporarily prevent any new carriers  104 , including either standard carriers  104  or high value carriers  104   h , from being sent to the workstation  100 . The system software will then proceed to dispense the correct high value carrier  104   h  to the workstation  100  for delivery to the authorized recipient. The system software alerts the recipients of the arrival of a high-value carrier  104   h  through various methods depending on a hospital&#39;s workflow processes. Alert methods may include posting a visual message on a touch control display of the workstation  100 , generating an audio alert, triggering a remote alert light, sending a message to a nurse-call system, communicating with a EMR (electronic medical record) system, or sending an email or text message. 
     The system software sets parameters for the credentials needed to release the high value carrier  104   h  into the arrival bin  110  of the workstation  100 . These parameters can establish delivery authorization rules that are broad, narrow or somewhere in-between. For example, a first rule for a given high value carrier  104   h  may allow any user with an employee badge to release the high value carrier  104   h , a second rule for a given high value carrier  104   h  may allow a subset of users, such as operating room nurses, to release the high value carrier  104   h , or a third rule for a given high value carrier  104   h  may allow only one specific person to release the high value carrier  104   h . Alternatively, these different levels of security precautions may be changed based on different sub-categorizations of high value carriers. When the system has determined that release of the high value carrier  104   h  is authorized, the carousel  114  rotates until the carrier port  116  containing the desired high value carrier  104   h  is aligned with the main arrival/departure system access tube  108 . The selection gate  120  is concurrently or subsequently moved to the open position, and the carrier  104   h  drops into the arrival bin  110 . 
     To dispense the stored high value carrier  104   h  from its respective port  116 , the carousel  114  and the selection gate  120  are detached to allow rotation of the carousel  114  while the selection gate  120  remains stationary. The carousel  114  is then rotated and the selection gate  120  remains fixed in the open position until the proper port  116  is in axial alignment with the main arrival/departure system access tube  108 , as shown for the carrier port  116   b  in  FIG. 2 j   . The stored high value carrier  104   h  is then dispensed to the arrival bin  110  through the opening in the selection gate  120  under its own weight/mass for a gravity-induced drop into the arrival bin  110  for retrieval by the authorized recipient. 
     After successful delivery of the high value carrier  104   h , the carousel  114  is rotated in the reverse direction, while the selection gate  120  remains fixed, until port  116   a  is once again in axial alignment with the main arrival/departure system access tube  108 , putting the carousel  114  and selection gate  120  into the default position whereby the workstation  100  remains open to send and receive other carriers  104 . The system software will then remove the block on incoming carriers  104  and will again allow carriers  104  to be received at the workstation  100 . The overall system can then continue unimpeded. A similar process may be used to dispense the high value carrier  104   h  from the carrier port  116   b . This process is repeated as high-value carriers  104   h  are stored in and retrieved from the secure vault  102 . 
     Those skilled in the art will understand that different operations, similar to those described above, can be used for storing carriers  104  in and retrieving carriers  104   h  from the secure vault  102  depending on the specifications of the secure vault  102 . For example, in other embodiments, a greater or lesser number of carrier ports  116  can be used. Only space saving considerations prevent the addition of more carrier ports  116  to the carousel  114 . Thus, where space considerations permit, any number of carrier ports  116  may be added to the carousel  114  allowing the workstation  100  to hold an increased number of high-value carriers  104   h  in the secure location while the workstation  100  remains open for normal receiving and send operations. However, in these embodiments, a more complex mechanism may be used for the storing and retrieval of the carriers  104   h  from the ports  116 . For example, the selection gate  120  may be configured to rotate independently from the carousel  114 . In another example, multiple selection gates  120  may be used in series. 
     As described above, the selection gate  120  and the carousel  114  comprise means for attaching so that the rotation of the carousel  114  is also imposed on the selection gate  120  and detaching so that the selection gate  120  remains fixed while the carousel  114  is rotated. 
       FIGS. 3 a - c    shows the exemplary carousel  114  of the previous Figures including the latch  124  for attaching the selection gate  120  to the platform  118  of the carousel  114 . The latch  124  is mounted upon and moves with the selection gate  120  during operation. In this example, the latch  124  comprises a solenoid that is normally extended and retracts upon delivery of voltage. When the solenoid is in a normal, non-energized position, the latch  124  engages the structure enclosing the carousel  114  so that the selection gate  120  cannot rotate, as shown in  FIG. 3 b   . This position may be considered a home position of the carousel  114  wherein the solenoid is de-energized and, should the solenoid fail, the workstation  100  will remain operational as a fail-safe operation. When the solenoid is in an energized position, the latch  124  disengages from the structure and engages the platform  118  of the carousel  114  so that the selection gate  120  will rotate when the carousel  114  is rotated. 
     Those skilled in the art will understand that the example provided in  FIGS. 3 a - c    is only exemplary, and different mechanisms may be used to attach the selection gate  120  to the carousel  114  and detach the selection gate  120  from the carousel  114 . 
     The carousel  114  can be rotated using various mechanisms. In one embodiment, the carousel  114  is driven by a 12 VDC gearmotor driving a Geneva mechanism  126 , as shown in  FIGS. 4 a - b   . The Geneva will provide exactly one revolution and then lock the axle position during the remainder of the motors one revolution. To move the carousel, the motor is energized for one revolution in the desired direction, and then reversed one revolution to bring the carousel back. If the gearmotor output is at 12 RPM, then one revolution from the gearmotor, motivating the carousel from one position to another, should be a 5 second cycle maximum. 
     An additional benefit of the secure vault  102  design is that, should a high-value carrier  104   h  not be released in a predetermined amount of time, the system software can create a transaction to remove the high value carrier  104   h  from the secure vault  102  and return it to its origin or to another location. To accomplish this task, the system will call for the secure vault  102  to dispense the high value carrier  104   h  in question from the workstation  100 . The carousel  114  is rotated to position the port  116  including the carrier  104   h  into a position aligned with the main arrival/departure system access tube  108 . At this point, a source of air beneath the carrier  104   h  is provided (e.g., through a separate valve or by partially opening the selection gate  120 ) while maintaining the carrier  104  in the secure location. The carrier  104   h  is then vacuumed out of the workstation  100  in the same manner as any other carrier  104 . 
     The secure vault  102  described above is located at the workstation  100  of the pneumatic tube system. Thus, the carriers  104 , including high value carriers  104   h , are routed through the pneumatic tube system using components, e.g., blowers, diverters, etc., shared with other workstations. That is, this system does not include any components separate from the workstation  100  in the pneumatic tubing system (e.g., upstream from the workstation  100 ) dedicated to the delivery of high value carriers  104   h.    
       FIG. 5  shows a pneumatic tube system  200  for the workstation  100  comprising the secure vault  102  of the previous Figures. The system  200  includes a system blower  204  servicing any number of workstations, including the workstation  100  and a number of further workstations  202 , via one or more diverters  206 . In this example, the diverter  206  is a four-port diverter. However, those skilled in the art understand that additional diverters or other components may be used downstream from a system blower. 
     In the example of  FIG. 5 , the system blower  204  places a carrier into the dedicated secure vault  102  of the workstation  100 , with final delivery of the carrier being achieved via gravity. In other embodiments, the carrier can be delivered under pressure from a blower. As described above, the dedicated secure vault  102  can store inbound high value carriers  104   h  and may additionally store standard carriers  104  if necessary, for example, when the access bin  110  is full. 
     In alternative embodiments, a secure carrier vault can be located separately from the workstation within the pneumatic tube system (e.g., upstream from the workstation). In these embodiments, the workstation may be a typical, existing workstation and the separate carrier vault may be dedicated to processing carriers to/from this one particular workstation. In other embodiments, the separate carrier vault can be dedicated to processing carriers for multiple workstations. This secure carrier vault located upstream from the workstation may be used as an additional secure storage location when a workstation is already holding a maximum number of carriers, for example in its arrival bin and/or attached carrier vault. In some embodiments, the separate carrier vault can be a modified diverter, for example comprising one port as a pass-through tube and additional ports as storage stubs. In other embodiments, the separate carrier vault can comprise functionality similar to the carrier vault attached to the workstation described above, e.g., comprising a rotatable carousel of carrier ports and a selection gate for preventing or allowing the carriers to pass through the vault to the workstation, to be described in further detail below with respect to  FIGS. 9 a   - f.    
       FIG. 6  shows a pneumatic tube system  300  comprising a diverter  308  with storage stubs  310  for use as a secure carrier vault. The system  300  includes a system blower  304  servicing any number of workstations  302 , via one or more standard diverters  306 . In this example, both the carrier vault diverter  308  and the standard diverter  306  are four-port diverters. Thus, the carrier vault diverter  308  has a port servicing the workstation  302   a  and three ports available as storage stubs  310  for holding high value carriers  104   h . Those skilled in the art understand that additional diverters or other types of diverters, e.g., diverters having a greater or lesser number of ports can be used. 
     In the example of  FIG. 6 , the system blower  304  places a carrier into the storage stubs  310  of the carrier vault diverter  308 , extracts the carrier from the carrier vault diverter  308 , and delivers the carrier to the workstation  302   a . Similar to above, the carrier vault diverter  308  can store inbound high value carriers  104   h  and may additionally store standard carriers  104 , if necessary, for example, when the access bin  110  of the workstation  302   a  is full. 
     In still another embodiment, the secure carrier vault can be located at a diverter upstream from the workstation, similar to the example of  FIG. 6 , and additionally the system can comprise a dedicated compact blower for processing carriers  104  for the carrier vault. 
       FIG. 7  shows a pneumatic tube system  400  comprising a dedicated compact blower  412  and a carrier vault diverter  408  with storage stubs  410  for use as secure carrier ports. The system  400  includes a system blower  404  servicing any number of workstations  402 , via one or more standard diverters  406 . In this example, both the carrier vault diverter  408  and the standard diverter  406  are four-port diverters. Thus, the carrier vault diverter  408  has a port servicing the workstation  402   a , e.g., as a pass-through tube, and three ports available as storage stubs  410  for holding high value carriers. Additionally, the system  400  comprises a dedicated compact blower  412  upstream from a further diverter  414  and the carrier vault diverter  408 . The further diverter  414  may have one port connected to the dedicated compact blower  412  and another port serving as a pass-through tube. 
     In the example of  FIG. 7 , the system blower  404  transmits a carrier downstream past the further diverter  414 . At this stage, the system blower  404  places the carrier into a stub  410  (port) of the carrier vault diverter  408 . The compact blower is used to extract the carrier after placement into the carrier vault diverter  408  under vacuum and deliver it to the destination workstation  402   a  under pressure. Thus, the system blower  404  does not need to be used for extraction and delivery of carriers and can be used instead to handle other deliveries. Similar to above, the carrier vault diverter  408  can store inbound high value carriers  104  and may additionally store standard carriers  104  if necessary, for example, when the access bin  110  of the workstation  402   a  is full. Additionally, the carrier vault diverter  408  can store outbound carriers  104  when downstream resources are busy. 
     In still another embodiment, a secure carrier vault can be located at a horizontal storage device upstream from the workstation, and the system can comprise a dedicated compact blower for processing carriers  104  for the carrier vault. 
       FIG. 8  shows a pneumatic tube system  500  comprising a horizontal storage device  508  for use as a secure carrier vault. In this example, the storage device  508  includes four tubes  510 , three of which are used as storage tubes and one of which is used as a pass-through tube, in coordination with a carrier stop plate  512  comprising a single hole that can rotate independently from the tubes  510 . The system  500  includes a system blower  504  servicing any number of workstations  502 , via one or more standard diverters  506 . Additionally, the system  400  comprises a dedicated compact blower  514  downstream from the storage device  508  and upstream from the workstation  502   a.    
     In the example of  FIG. 8 , the system blower  504  transmits a carrier downstream to the storage device  508 . When the carrier is stored in the storage device  508 , the compact blower  514  can extract the carrier from the storage device  508  and deliver the carrier to the workstation  502   a . Thus, the system blower  504  can be used to handle other deliveries. Similar to above, the storage device  508  can store inbound high value carriers  104   h  and may additionally store standard carriers  104  if necessary, for example, when the access bin  110  of the workstation  502   a  is full. 
     The storage device  508  can comprise functionality similar to the carrier vault attached to the workstation described above. The tubes  510  serving as carrier ports can be included in a rotatable carousel and the stop plate  512  serves as a selection gate for preventing or allowing the carriers to pass through the device  508  to the workstation  502   a . In this example, the carousel and the stop plate can rotate independently from one another. 
       FIGS. 9 a - c    show views of an exemplary storage device  600  for use as a carrier vault separate from a workstation in a pneumatic tube system (e.g., located in a ceiling or other space separated from the workstation in the same or a different room). In this example, the storage device  600  comprises a rotatable carousel  602  supporting five tubes, wherein a first tube  604  is used as a pass-through tube and the remaining four tubes are used as carrier ports  606  for storing carriers. The storage device  600  further comprises a first access port  608  for receiving carriers transmitted downstream to the workstation (and for transporting carriers transmitted upstream from the workstation) and a second access port  610  for transporting carriers downstream to the workstation (and for receiving carriers transmitted upstream from the workstation). 
     The carousel  602  is rotatable within the storage device  600  so that any one of the five tubes can be brought into alignment with the access ports  608 ,  610 . The carousel  602  can be rotated using a first motor. Between the carousel  602  and the second access port  610  is a stop plate  612 , which is rotatable independently from the carousel  602 , for example using a second motor. In this example, the stop plate  612  includes three tube stubs, as shown in the cross-sectional view of  FIG. 9 d   . A first tube stub  614  is open on both ends and is used as a pass-through tube, while the remaining two tube stubs  616  are closed on the ends adjacent to the second access port  610 . 
     When a carrier is to pass through the storage device  600 , the tube stub  614  is brought into alignment with second access port  610 . When a carrier is to be captured and stored within the storage device  600 , either of the tube stubs  616  can be brought into alignment with the second access port  610 . Those skilled in the art understand that only a single tube stub  616  can be used in the design of the storage device  600 , rather than two tube stubs  616 . The closed end of the tube stub  616  can provide an air cushion to slow incoming carriers arriving into a carrier port  606  of the carousel  602  as would be understood by those skilled in the art. 
     In default operation, the pass-through tube  604  of the carousel  602  is aligned with the first and second access ports  608 ,  610  so that carriers directed toward or leaving the workstation can freely pass through the storage device  600 , as shown in the cross-sectional views of  FIGS. 9 e - f   . When an incoming carrier is to be stored in the device  600 , prior to arrival of the carrier at the device  600  the carousel  602  is rotated so that one of the carrier ports  606  is aligned with the first access port  608  and the stop plate  612  is rotated so that the tube stub  616  blocks access to the second access port  610 . The carrier is received in the carrier port  606  and is slowed by an air cushion provided by the tube stub  616  so that the carrier stops within the carrier port  606 . The carousel  602  and the stop plate  612  may then be rotated back into their respective pass-through positions, securing the carrier in the storage device  600 . A similar method can be used to store additional carriers in the remaining carrier ports  606 . 
     To remove a stored carrier from a given carrier port  606 , the carousel  602  is rotated to return the carrier port  606  into alignment with the second access port  610  with the stop plate  612  in its pass-through position. A dedicated compact blower, e.g., the compact blower  412  of  FIG. 7  or the compact blower  514  of  FIG. 8 , can be used to force the carrier out of the carrier port  606  and through the second access tube  610  under vacuum/pressure for delivery to the workstation. Alternatively, any system blower may be used to push the carrier to the workstation. As would be understood by those skilled in the art, the provision of a dedicated compact blower, may enhance system performance as, during the operation to pass a carrier from the device  600  to the workstation, the system blower will remain available to route carriers throughout the system as desired. 
     As discussed above, the carrier ports  606  comprise tubes sized and shaped similarly to the those used in the pneumatic tubing system. In the example of  FIG. 9 , the carrier ports  606  are slotted to relieve the air pressure of incoming carriers as the momentum is slowed by the stop plate  612 . Additionally, the carrier ports  606  may comprise optical sensors for detecting arriving carriers. Furthermore, as would be understood by those skilled in the art, the slots in the carrier ports  606  are located so that, when a carrier is received therein, a seal of the carrier is between the workstation and the slots so that suction applied by the dedicated compact blower is not diminished by leakage from the slots. Alternatively, the slots may be selectively closable via any known valves so that they may be located anywhere along the carrier ports  606  without diminishing the efficacy of suction pressure applied by the dedicated compact blower. Such valves would also allow slotted carrier ports  606  to be used efficiently with a pushing pressure applied by a system blower (i.e., the valves would prevent leakage of pushing pressure from the slots). 
     The storage device described in  FIG. 9  is preferably used in a pneumatic tubing system arrangement comprising a dedicated compact blower for extracting carriers from the device and delivering the carriers to the workstation. A system blower may not be able to accelerate the stationary carrier from a distance, thus the compact blower provides a local vacuum or pressure for accelerating the carrier from the device and delivering the carrier to the According to one example, a storage device of a pneumatic tube system comprises a rotatable carousel comprising at least a first tube and a second tube, each tube sized and shaped to permit passage of a carrier used to transport materials via the pneumatic tube system, the carousel being configured to rotate between a first position, where the first tube is aligned with an access tube of the pneumatic tube system, and a second position, where the second tube is aligned with the access tube. 
     The storage device further comprises a stop plate adjacent to the carousel comprising an open tube stub and at least one closed tube stub, the stop plate being configured to rotate between an open position, where the open tube stub is aligned with the access tube and the carrier is allowed to pass through the stop plate, and a closed position, where the closed tube stub is aligned with the access tube and the carrier is prevented from passing through the stop plate. When an arriving carrier is to be stored in the storage device, the carousel is rotated to or maintained in the second position and the stop plate is rotated into or maintained in the closed position to receive the arriving carrier in the second tube. When the arriving carrier is received in the second tube, the carousel is rotated to the first position and the stop plate is rotated into the open position so that the arriving carrier is stored in the storage device and the workstation remains available for subsequent carrier transmissions through the first tube. 
     According to another example, the closed tube stub provides an air cushion to slow arriving carriers. According to still another example, the second tube comprises at least one slot to relieve air pressure caused by the arriving carrier. According to still another example, when the stored carrier is to be delivered to a workstation, the carousel is rotated to the second position and the stop plate is rotated into or maintained in the open position to allow the stored carrier to be extracted from the storage device. According to still another example, a dedicated blower is used to provide a vacuum or a pressure to force the stored carrier through the stop plate and deliver the carrier to the workstation. 
     Although this application describes various embodiments each having different features in various combinations, those skilled in the art will understand that any of the features of one embodiment may be combined with the features of the other embodiments in any manner not specifically disclaimed or which is not functionally or logically inconsistent with the operation of the device or the stated functions of the disclosed embodiments. 
     It will be apparent to those skilled in the art that various modifications may be made in the present disclosure, without departing from the spirit or the scope of the disclosure. Thus, it is intended that the present disclosure cover modifications and variations of this disclosure provided they come within the scope of the appended claims and their equivalent.