Abstract:
A passenger restraint system for a vehicle having a plurality of seats, each seat having a seatbelt, a retractor from which the seatbelt is extendable, and a receiver used to latch the seatbelt. Each retractor includes a first pneumatic locking element and a second pneumatic locking element for limiting movement of the seatbelt and each receiver includes a receiver pneumatic locking element for locking the seatbelt within the receiver. A controller controls the operation of a plurality of first valves for supplying air to the first pneumatic locking element of a corresponding one of the plurality of retractors, a second valve for supplying air to each of the second pneumatic locking element of the plurality of retractors, and a plurality of third valves for supplying air to the receiver pneumatic locking element of a corresponding one of the plurality of receivers. Control decisions may be made based upon feedback received from sensors within the receiver that sense a state of the seatbelt with respect to the receiver.

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. Utility patent application Ser. No. 10/979,846, filed Nov. 1, 2004, which claims the benefit of and priority to U.S. Provisional Application No. 60/516,110, filed Oct. 31, 2003, the contents of which are incorporated by reference in their entirety. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     The following generally relates to systems and methods for safely restraining passengers, such as passengers of an amusement ride. 
     2. General Background and State of the Art 
     In the art, passenger restraint systems are known. For example, commonly assigned U.S. Pat. No. 5,182,836, which is incorporated herein by reference in its entirety, discloses a passenger restraint system including a pressure activated seatbelt locking device that allows an operator to control the locking and unlocking of seatbelts, such as those used on amusement rides, from a remote location. To this end, the described seatbelt locking device has a buckle portion into which a latching tongue is inserted and held by a retractable element which extends though an aperture in the latching tongue. The latching tongue can be removed from the buckle by depressing a release latch to disengage the retractable element from the aperture. The seatbelt locking device is further provided with a pneumatically inflatable air bladder which is exerted against a pivotable lever lock when properly inflated. The inflation of the air bladder causes the lever lock to pivot and bear against the lower end of the release latch, such that the release latch cannot be depressed by the user of the seatbelt to disengage the retractable element from the latching tongue. Accordingly, the seatbelt is retained in the locked position until the air bladder is deflated such that the lever lock pivots away from the release latch. 
     While such a passenger restraint system does work well for its intended purpose, a need does exist for an improved passenger restraint system, in particular, a passenger restraint system that, among other things, ensures that under any single-point failure the passenger restraint system seatbelt will not automatically disengage at an undesired time and/or which inhibits or restricts vehicle motion if a failure is detected in the passenger restraint system to thereby allow for an appropriate response. A need also exists for an improved passenger restraint system that allows for the use of the same components in multiple locations to, for example, reduce costs associated with spare parts inventory, training maintenance technicians, etc. 
     SUMMARY 
     The following describes a passenger restraint system having in one embodiment, one or more seatbelts comprised of a retractor, used to adjust or tighten the seatbelt, and a receiver, used to engage, latch, and lock the seatbelt. In this regard, a latched seatbelt is one wherein the seatbelt receiver has fully engaged a tongue with a cam such that the tongue cannot be physically removed without depressing a release button (i.e., the tongue is fully inserted and the cam is fully extended and engaged through the tongue) and a locked seatbelt is one that cannot be manually unlatched through use of the release button. The seatbelts may also be arranged and configured to provide redundancy in the mechanism used to lock the seatbelt. 
     For use in monitoring the status of the seatbelts, the passenger restraint system may also be provided with a feedback control system comprised of one or more sensors. The sensors may then be monitored to determine the status of individual seatbelts (e.g., latched, locked). The feedback control system may also provide clear indication to an operator, for example of an amusement ride, that an individual seatbelt has been properly engaged/latched (e.g., by means of a fast blinking status indicator), failed (e.g., by means of a slow blinking status indicator), or disengaged/unlatched (e.g., by means of no status indicator blinking). Still further, the sensors may be utilized to provide status that allows the system to intelligently control the pneumatic locking and unlocking of seatbelt components. 
     A better understanding of the various objects, advantages, features, properties, and relationships of the passenger restraint system will become apparent from the following detailed description and accompanying drawings which set forth illustrative examples which are indicative of the various ways in which the principles of the passenger restraint system may be employed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Exemplary passenger restraint systems are described hereinafter with reference to the following drawings in which: 
         FIG. 1  is a block diagram illustrating an exemplary passenger restraint system; 
         FIG. 2  is a timing diagram illustrating exemplary signals utilized in connection with the passenger restraint system of  FIG. 1 ; 
         FIGS. 3   a - 3   e  illustrate an exemplary embodiment of a retractor without a sensor in accordance with the present disclosure; 
         FIGS. 4   a - 4   e  illustrate an exemplary embodiment of a retractor with a sensor in accordance with the present disclosure; 
         FIGS. 5   a - 5   d  illustrate an exemplary embodiment of a receiver having a single lock pawl assembly in accordance with the present disclosure; 
         FIGS. 6   a - 6   d  illustrate an exemplary embodiment of a receiver having a dual lock pawl assembly in accordance with the present disclosure; and 
         FIGS. 7   a - 7   d  illustrate an exemplary embodiment of a receiver having a dual lock pawl assembly in accordance with the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     With reference to the figures, the following describes exemplary passenger restraint systems. In this regard, the passenger restraint systems may be utilized in connection with a vehicle, such as found in an amusement ride, wherein each seat in the ride, which will be occupied by a guest, is fitted with several seatbelt components provided to restrain a guest within the seat. Generally, the seatbelt components include a seat belt (including a belt web  10  and a tongue  12  having an aperture), a lockable belt retractor reel  14  (illustrated by way of example in  FIGS. 3   a - 3   e  and  4   a - 4   e ), a lockable latching seatbelt receiver  16  (illustrated by way of example in  FIGS. 5   a - 5   d ,  6   a - 6   d  and  7   a - 7   d ), and pneumatic valves for each receiver and retractor. Each receiver  16  may be further provided with three types of proximity sensors, namely, a tongue in place (“TIP”) sensor  18 , a cam in place (“CIP”) sensor  20 , and a lock in place (“LIP”) sensor  22 . As illustrated in  FIG. 1 , the various sensors provide information to a seatbelt monitoring system (“SBMS”)  24  which may be embodied in an on-vehicle, programmable logic controller (“PLC”) that provides supplementary monitoring and redundant control of certain seatbelt functions. In turn, the SBMS is in communication with a vehicle control system (“VCS”)  26  that provides on-board control for various vehicle functions. As will be described hereinafter, the SBMS  24  and the VCS  26 , each of which includes executable instructions on a readable media for the purpose, among others, of receiving, processing, and generating signals, cooperate to monitor and control the seatbelt components to thereby lock and unlock the receiver  16  and retractor  14 . In particular, the SBMS  24  monitors the state and sequence of the receiver sensors and indicates valid and faulted conditions via status signals to the VCS  26 . The VCS  26  and the SBMS  24  thus cooperate to issue control signals for locking and unlocking the seatbelts. In addition, the SBMS  24  may cause the state of the seatbelt to be displayed to a ride operator by means of status indicators  28 , for example located on an operators display panel (“ODP”). Preferably, each seatbelt would have a corresponding status indicator on the ODP and, therefore, each status indicator may be used to indicate the state of its corresponding seatbelt as being, for example, one of the following: not buckled; buckled and no faults; or buckled and sensor or lock fault. The use of the ODP is advantageous since the SBMS  24  itself is unable to detect the presence of a guest in a seat and, as such, the ride operator can inspect the ODP to ensure that each status indicator  28  indicates a valid “latched-and-locked” state before dispatching the vehicle onto the ride, regardless of whether or not the seat is physically occupied by a guest. In addition, the VCS  26  may be programmed to prevent a ride operator from initiating vehicle motion, for example from a station belt check position, until the SBMS  24  indicates that no faults exist on any seats. 
     For operating the locking mechanisms of the receivers  16  and retractors  14 , the passenger restraint system includes a pneumatic sub-system  30  that functions to provide pressurized air to the locking mechanisms of receivers  16  and retractors  14 . In this regard, each lap belt retractor  14  may contain two separately controlled locking pawl assemblies  32 , e.g., comprised of a pin, pawl, lock, and reel, that are pneumatically actuated. In the illustrated examples, one locking pawl assembly  32  is positioned on each of the left and right hand sides of a spring loaded reel shaft  34  having an aperture through which passes the belt web  10 , thus providing redundant locking pawl assemblies  32  that create redundant load paths. Air is required to release each pawl and the retractor  14  is unlocked when both pawls are released, thus allowing the belt to be extended through the aperture in the reel shaft  34 . The air supplied to one side of the retractor  14 , i.e., one locking pawl assembly  32 , is controlled by the SBMS  24  via an individual lap belt retractor valve—each retractor  14  in the vehicle has a corresponding individual lap belt retractor valve. The air supplied to the other side of the retractor, i.e., the other locking pawl assembly  32 , is controlled by the VCS  26  via a group lap belt retractor valve—there is one group lap belt retractor valve in the vehicle that supplies air to all of the retractors  14 . All lap belt retractor valves within a vehicle are normally closed. Thus, in the absence of power, the retractor reel  34  will be locked to prevent the seat belt from being extended. The spring-loaded retractor reel  34  is provided to maintain tension on the seat belt web at all times. Furthermore, one or more optional proximity sensors  36  may be provided to provide additional retractor status information to the SBMS/VS systems. 
     Similarly, each receiver contains a pneumatic locking mechanism  38 , e.g., comprising a pawl, lock, and latch. For example,  FIGS. 5   a - 5   d  illustrate an exemplary embodiment of a receiver having a single lock pawl assembly.  FIGS. 6   a - 6   d  and  7   a - 7   d  illustrate exemplary embodiments of a receiver having a dual lock pawl assembly in accordance with the present disclosure. When actuated, the locking mechanism  38  prevents a release button  40  from being pressed, thus preventing the tongue  12  of the seat belt from being disengaged. Air is utilized to lock the receiver  16 . The air supply to each receiver  16  is controlled by the SBMS  24  via a corresponding individual receiver lock valve—each receiver  16  in the vehicle has a corresponding individual receiver lock valve. The individual receiver lock valves are normally open. However, in the absence of power, the receiver  16  would be unlocked because an upstream supply valve, the solenoid valve, would be closed. 
     Pressurized air utilized to operate the locking mechanisms of all receivers  16  and retractors  14  is supplied from a compressed air system. In particular, air is supplied to the receiver and retractor legs of the system through a pressure regulator and the solenoid valve. The solenoid valve is turned on, i.e., opened, by the VCS  26  to enable the receiver locking and retractor unlocking. The solenoid valve is turned off, i.e., closed, by the VCS, Vehicle E-Stop, or loss of power. When the solenoid valve is closed, all receivers  16  become unlocked and all retractors  14  become locked. Pressure within the system may be monitored by a seat belt low air pressure switch, with the status being provided to the SBMS/VCS systems. In particular, the pressure switch detects the air pressure at the output of the main air valve and may be set to detect the minimum pressure required to validate correct valve operation. 
     In operation, after loading a vehicle, guests are generally required to insert the seat belt tongue  12 , which is attached by the belt web  10  to the spring-loaded reel  34 , into the associated seat belt receiver  16 . When unloading, the guests depress the spring-loaded release button  40  of the receiver  16  to unlatch the tongue  12  from the receiver  16  to free themselves from the passenger restraint system. Meanwhile, ride operators receive from the system indications of the status of each seat belt, and have the ability to manually override the automatic operation of the system, described hereinafter, to lock and unlock the receivers  16 . Thus, ride operators may use the system to verify that all seats identified by the system as being properly latched and locked are not occupied by a guest. 
     With respect to the automatic locking and unlocking of the various restraint components (e.g., the receivers  16  and retractors  14 ), the system is responsive to signals provided by the SBMS/VCS. More particular, the signals may be generated by the SBMS/VCS considering feedback from the sensors and/or the position of the vehicle within the ride. For example, the SBMS  24  may generate a signal to automatically lock the retractor  14  whenever the corresponding tongue sensor detects a tongue  12  in the receiver  16 . Similarly, when the VCS  26  removes a seatbelt enable signal, the SBMS  24  may generate a signal to lock all retractors  14  and the VCS  26  may generate a signal to close the group lap retractor release valve, thus locking both sides of the retractor  14 . Still further, the lap belt retractor locks may be unlocked when the VCS seatbelt enable signal is on and the VCS Seatbelt lock signal is off in which case the VCS  26  energizes (i.e., opens) the group lap belt retractor release valve and, as each belt is sensed to be unlatched from the receiver, the SBMS  24  may send a signal to energize (i.e., open) the corresponding individual lap belt retractor release valve thereby allowing the seatbelt to be retracted. 
     By way of more specific example and with reference to  FIG. 2 , an illustrative sequence of events for the system will be described. In this example, it is to be understood that the retractor locks  32  are locked and unlocked when the following conditions occur: 
     1) The VCS seatbelt lock signal is on—as each belt is latched into the receiver  16 , the SBMS  24  sends a signal to close the corresponding individual lap belt retractor release valve; or 
     2) The VCS seatbelt enable signal is off—the VCS  26  sends a signal to close the group lap belt retractor release valve and the SBMS  24  sends a signal to close all individual lap belt retractor release valves. 
     It is also to be understood that the receiver lock  38  is unlocked when the following conditions occur: 
     1) The VCS seatbelt enable signal is on and the VCS seatbelt lock signal is off—the VCS  26  sends a signal to close the solenoid valve and the SBMS  24  sends a signal to close all individual receiver lock valves. 
     Finally, it is to be understood that the receiver lock  38  is locked when the following conditions occur: 
     1) The VCS seatbelt lock signal is on—the VCS  26  energizes (i.e., opens) the solenoid valve, the SBMS  24  monitors the transition of the TIP and CIP sensors, and, as each receiver is latched, the SBMS  24  sends a signal to open the corresponding individual receiver lock valve; or 
     2) The VCS seatbelt enable signal is off—the SBMS  24  sends a signal to de-energize (i.e., open) all individual receiver lock valves. 
     The seatbelt enable command is provided by the VCS  26  to the SBMS  24  and the SBMS  24  monitors this signal to begin the seatbelt cycle check, e.g., when the signal transitions from low to high. When the signal is inactive (i.e., low), the SMBS  24  turns off all outputs to seat indicators  28 , retractor locks  38 , and receiver locks  32 , as described below. 
     Turning now to illustrative example of  FIG. 2 , when a vehicle arrives and parks at a load/unload position, the VCS  26  turns on a seatbelt enable signal and turns off a lock signal. At this time, all receivers  16  are unlocked by the SBMS  24  and VCS  26 . In this manner, each guest may then press the guest release button  40  on the receiver  16  which releases the tongue  12  whereby the seatbelt is free to be retracted by the retractor reel to allow the guest to unload from the vehicle. In particular, as each receiver  16  is unlatched, the corresponding retractors  14  will be unlocked to allow the seatbelt to be extended for the next guest. 
     As guests are loaded into the vehicle, the guest extends the seatbelt and inserts the tongue  12  into the receiver  16 . The status of the tongue  12  with respect to the receiver  16  is sensed by the system. Once all guests are seated, the operator may signal the system as to the desire to commence the ride, for example by causing the vehicle to advance. In response, the VCS  26  turns on the seatbelt lock command and the receivers  16  that already have a tongue  12  inserted will be locked by the SBMS  24 , as are the corresponding lap retractors  14 . All other receivers  16  and retractors  14  may remain unlocked until they have a tongue  12  inserted and are latched. As noted, the SBMS  24  monitors the transitions of the sensors to validate that they are operating correctly and to determine the status of the receiver  16 . To validate the sensors, for example, it must be sensed that a tongue  12  was removed from and reinserted into the receiver  16  at least once between lock cycles. When the SBMS  24  determines that a receiver  16  has been properly latched and locked, a signal indicative of the status may be sent to the ODP for use in providing a locked status indicia to the ride operator. Thus, seats that have not been buckled or which do not have the tongue fully inserted will not have the appropriate indicia present thereby notifying the operator that guest assistance may be necessary. Similarly, the SBMS  24  may generate a signal indicative of a seatbelt fault condition, e.g., a determined sensor failure, that is sent to the ODP for use in providing a fault status indicia to the operator. 
     At this time, if a guest wishes to change seats or there is a problem with the seatbelt, the operator may use a manual seatbelt unlock switch  42  to unlock all seatbelts. The guest may then be instructed to release their seatbelt by pressing the seatbelt release button  40  to thereby allow the guest to relocate to a different seat and/or buckle their seatbelt again. Once the manual seatbelt unlock switch  40  is released, all seatbelts may again be locked. 
     At this time, the operator may dispatch the vehicle into the ride. However, if there is a fault within the system, the VCS  26  will inhibit motion. Otherwise the ride is dispatched and the VCS  26  turns off the seatbelt enable which, in turn, turns off the power used to release the retractors  14  and unlock the receivers  16 —all receivers  16  and retractors  14  will thus become locked regardless of whether or not they are latched. The SBMS  24  may also generate a signal to turn off all seat status indicator elements  28  at this time. 
     Upon the return of the vehicle to the unload/load position, the VCS  26  turns on the seatbelt enable which turns off the power for the retractor and receiver locks and enables that status indicator elements  28 . The VCS  26  also turns off the seatbelt lock command whereupon the SBMS  24  may unlock all receiver locks. As noted previously, the system may monitor the change in state of each sensor during unlocking to verify that the sensors are working properly. At seats that remain empty during the consecutive cycles, only the lock sensor will transition when the lock command is turned on and off. 
     During the ride, the receiver sensors may be further monitored for the purpose of providing feedback useful in determining vehicle status to thereby allow for further control of the operation of the ride. 
     As noted, a manual seatbelt unlock switch  42  (e.g., a two-position, spring return mushroom button) may be provided and monitored by the VCS  26 . When a vehicle is first powered-up all the seatbelts are enabled and locked, meaning that they can be extended from the retractor  14  if they are not latched but become locked immediately upon becoming latched or upon initiation of motion. The manual seatbelt unlock switch  42  may thus be utilized to override the default state of the system, preferably provided that the vehicle is not moving. 
     To allow for the inspection of the lap belt retractors, a retractor test switch  44  may be provided. By way of example, this test switch  44  may have three positions, namely, “Off,” “A,” and “B.” In the “Off” position, the seatbelts operate normally and this position should be required for normal ride operation. In the “A” position, the locking pawl assemblies  32  controlled by the group lap retractor release valve are supplied air to unlock them. Simultaneously, the VCS  26  removes the seatbelt enable command to the SBMS  24  so that the individually controlled locking pawl assemblies  32  remain locked, i.e., this is the default response of the SBMS  24  when the enable is removed. This effectively causes one locking pawl assembly  32  on each retractor  14  to become locked and the other to become unlocked. In the “B” position, the VCS removes air from the ganged locking pawl assemblies  32 , i.e., via control of the group lap retractor release valve, to lock the locking pawl assemblies  32  and supplies the seatbelt enable command to and removes the seatbelt lock command from the SBMS  24  so that the individually controlled locking pawl assemblies  32  are unlocked—this is the default response to the SBMS  24  when the enable is applied and the lock is removed. Thus, in the “B” position, the lap retractor locking pawl assemblies  32  assume the opposite state of test mode “A” and, in either the “A” or “B” test modes, only one side of the lap belt retractor  14  will be unlocked. In this manner, the retractor operation can be validated by manual inspection. 
     The retractor test modes may be activated when the vehicle is in a station area where the seatbelts would normally be unlocked or when the manual seatbelt unlock switch  42  is selected while the vehicle is stopped at any position on (or off) the ride track. At all other time, the retractor test switch  44  may be ignored and the seatbelt retractors  14  allowed to operate normally. Furthermore, a message may be generated by the VCS  26  if the test switch is determined to be in an invalid position. Still further, when either retractor test mode is active, the SBMS  24  will be in a state where the seat indicators elements  28  should not indicate a valid seatbelt, e.g., the will be in a state indicative of a fault or unlatched seatbelt. 
     For indicating the status of a seatbelt, the ODP may provide indicia in the form of visual and/or audio emissions that are representative of a status. By way of example, different colors, different sounds, different light emission patterns, etc. may be utilized to represent different statuses/states of the seatbelt. In the illustrative example, the seatbelt indicator  28  utilizes two distinctive flashing rates to indicate a corresponding status. In this case, a fast flashing rate, e.g., 2.5 Hz, may be used to indicate that the seatbelt is latched and locked and all receiver sensors have transitioned since the seatbelt enable signal was turned on, i.e., that the corresponding seatbelt has been correctly latched and locked. Likewise, a slow flashing rate, e.g., 0.5 Hz, may be used to indicate that the seatbelt has a fault condition. A non-illuminated status element  28  may further be used to indicate that a seatbelt has not been latched. When a fault condition is signaled, the remaining seat status indicating elements  28  may be turned off so that only the faulted seatbelt will be called to the attention of the operator. Status conditions may also be provided to, for example, a hand-held message display. 
     As will be further appreciated from the figures, the components can be configured for various different applications while retaining several common components. For example, the receiver may be provided with a single locking pawl assembly, as illustrated in  FIGS. 5   a - 5   d , or with dual, pneumatic locking pawl assemblies, as illustrated in  FIGS. 6   a - 6   d  and  7   a - 7   d . When dual locking pawl assemblies are utilized, air may be supplied to the redundant locking pawl assembly of each receiver by individually controllable valves or by means of a single valve that is upstream of each of a ganged collection of locking pawl assemblies. Still further, as illustrated in  FIGS. 6   a - 6   e  and  7   a - 7   e , the use of dual, redundant locking pawl assemblies in the receiver may also require the use of dual CIP sensors  20  for providing feedback to the SBMS  24 . 
     Thus has been described a fail-safe passenger restraint system. However, while specific examples have been described and illustrated in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. For instance various well-known controllable locking mechanisms may be substituted for the pneumatically activatable locking pawl assemblies presented by way of example only. Accordingly, the particular arrangement disclosed is meant to be illustrative only and not limited as to the scope of the invention which is to be given the full breadth of the appended claims and any equivalents thereof.