Abstract:
A restraint for retaining a person within a seat. The restraint has a lap bar and a shoulder bar which can be independently adjusted. The lap bar can be rotated either to retain a person or to permit a person to enter or exit. Also, the lap bar can be pulled farther away or pushed closer to a person. When extended completely, the lap bar will remain locked in such position until the lap bar is rotated toward the position a person will occupy. When pushed toward a person, the lap bar cannot be pushed farther away until a rod to which the lap bar is attached is released from a lock. The shoulder retainer is attached to a similar rod which is locked in this same fashion.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    This invention relates to a restraint for retaining a person within a seat.  
           [0003]    2. Description of the Related Art  
           [0004]    The Inventor is aware of no other rigid restraint employing a rod lock as described in this invention for the lap of a person within a seat and is also aware of no rigid restraint which can be adapted both to the height and lap size of a participant.  
           [0005]    A hydraulic lock such as the one discussed below was employed on amusement rides by S &amp; S Sports Power, Inc. of Logan, Utah, that was available to the public on or shortly after Oct. 18, 1994.  
           [0006]    A locking apparatus similar to the one considered below was employed on amusement rides by S &amp; S Sports Power, Inc. of Logan, Utah, on or shortly after Aug. 4, 2001, and is the subject of copending U.S. application Ser. No. 09/922,588, filed on Aug. 3, 2001.  
         SUMMARY OF THE INVENTION  
         [0007]    In its most basic form, the Restraint of the present invention is a lap retainer which includes a lap bar attached to a second end of a rod at such an angle that the lap bar can retain a person in a seat to which a rod lock for the rod has been attached.  
           [0008]    The rod lock precludes longitudinal motion of the rod either continuously or discretely along a portion of the rod  
           [0009]    A preferred rod lock is the locking apparatus of the present invention that utilizes a rod wherein the diameter of the rod varies periodical as one moves along the rod from a first end; it is, thus, termed a serrated rod. The locking apparatus also includes a block having an aperture. The maximum thickness of the rod is less than the minimum diameter of the aperture in the block so that the rod can be inserted into the aperture.  
           [0010]    Between the center of the aperture and a first end of the block, the block is rotatably attached to a support structure, and the second end of the block is biased toward the direction from which the rod is intended to be inserted. The biasing of the block reduces the minimum diameter of the aperture as projected perpendicular to the longitudinal axis of the rod. The projected minimum diameter of the aperture is then less than the periodic maximum diameter of the rod so that pushing the rod into the aperture tends to decrease the biasing, thereby increasing the minimum projected diameter of the aperture, until the minimum projected diameter of the aperture exceeds the periodic maximum diameter of the rod so that the rod can enter the aperture. Continuing to push the rod enables it to proceed farther into the aperture. As the rod is pushed farther into the aperture, however, the biasing pushes the edge of the aperture into a portion of the rod between periodic maximum diameters. Then attempting to withdraw the rod causes the rod to pull the block and thereby either maintain or increase the biasing, which consequently reduces the projected diameter of the aperture and precludes withdrawal of the rod.  
           [0011]    When it is desired to release the rod, any means well known in the art for applying a physical force is used to push against or pull the block to reduce the biasing. The preferred means is, however, a sheathed cable with the sheath attached to the support structure for the block and the cable attached to the block or to a lever that presses against the block.  
           [0012]    Preferably, but not necessarily, a sensor detects whether the rod has been inserted into the aperture.  
           [0013]    Also, the locking apparatus preferably has two blocks. The first block and second block are located at such a distance from one another that the aperture in one block will be at a point of minimum thickness of the rod while the other block is at a point of maximum thickness of the rod.  
           [0014]    Other non-exclusive examples of acceptable rod locks are are any type of ratchet lock that is well known in the art and a hydraulic lock  
           [0015]    Preferably, the Restraint also includes a shoulder retainer having a shoulder bar that is connected to a second rod which fits into a rod lock similar to that for the lap belt. The support structure for the shoulder retainer is attached to the seat in such a position and with such an orientation that the second rod permits the should bar to be changed from position to position to accommodate persons of different heights.  
           [0016]    Preferably, the lap bar is rotatable but can be locked into position to retain a person in a seat.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    [0017]FIG. 1 provides a normal view of the locking apparatus.  
         [0018]    [0018]FIG. 2 is an exploded view of the locking apparatus.  
         [0019]    [0019]FIG. 3 shows a rod having its second end in the shape of a loop.  
         [0020]    [0020]FIG. 4 illustrates a rod having screw threads on its second end.  
         [0021]    [0021]FIG. 5 is a lateral view of the preferred embodiment of the lap retainer with the figure subdivided into FIG. 5 a  having the sleeves cut away to illustrate the telescoping release rod, FIG. 5 b  to portray the gas cylinder, and FIG. 5 c  to depict the device to hold the lap retainer at its most extended position.  
         [0022]    [0022]FIG. 6 is an isometric view of the Restraint attached to the framework of a seat.  
         [0023]    [0023]FIG. 7 depicts the preferred embodiment of the lap retainer with the lap retainer rotated ninety degrees around the longitudinal axis of the rod with respect to the view of FIG. 5 a.    
         [0024]    [0024]FIG. 8 portrays the preferred embodiment of the shoulder retainer.  
         [0025]    [0025]FIG. 9 is a lateral view of the preferred embodiment of the shoulder retainer with the shoulder retainer rotated ninety degrees around the longitudinal axis of the rod with respect to the view of FIG. 8.  
         [0026]    [0026]FIG. 10 shows the hydraulic lock.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0027]    A key feature of the present Restraint is termed a rod lock  1 . The rod lock  1  precludes longitudinal motion of a rod  103  either continuously or discretely along a portion of the rod  103 .  
         [0028]    A preferred version of the rod lock  1  is termed the “locking apparatus.” 
         [0029]    The locking apparatus has a block  101  containing an aperture  102 .  
         [0030]    A rod  103  is removably insertable into the aperture  102 . The rod  103  employed with the locking apparatus is serrated, i.e., the thickness of the rod  103  varies periodically along a portion  104  of the length of the rod  103  beginning near a first end  105  of the rod  103 .  
         [0031]    The maximum periodic thickness  106  of the rod  103  is less than the minimum diameter of the aperture  102  in the block  101  so that the rod  101  can be inserted into the aperture  102 .  
         [0032]    Between the center of the aperture  102  and a first end  107  of the block  101 , the block is rotatably attached to a support structure  108 . The block  101  is biased so that the second end  109  of the block  101  is farther toward the direction from which the rod  103  is intended to be inserted that is the first end  107  of the block  101 . Preferably, but not necessarily, such biasing is done between the center of the aperture  102  and a second end  109  of the block  101 .  
         [0033]    Biasing may be accomplished by any device  110 , such as a spring that will exert a physical force between the block  101  and the support structure  108 . Preferably, but not necessarily, the block  101  contains a first depression  111  to hold a first end  112  of the device  110 ; and preferably, but not necessarily, the support structure  108  contains a second depression  113  to hold a second end  114  of the device  110 .  
         [0034]    The second end  115  of the rod  103  is available for connection to a restraining device such as the cloth of a seat belt or a bar and is shaped to accommodate such restraining device. This shape is generally a loop for a seat belt or screw threads for insertion into a bar.  
         [0035]    Operation of the locking apparatus was discussed above. From that discussion it will be apparent that the further the rod  103  is pushed into the block  101 , the tighter the restrain will be.  
         [0036]    And, as also considered above, any means well known in the art for applying a physical force is used to push against or pull the block  101  to reduce the biasing. Such a means may, e.g., be a manually operated rod or lever, a cable attached to the block  101  to pull the block  101 , a motor, a hydraulically powered rod to push the block  101 , or a pneumatically powered rod to push the block  101 .  
         [0037]    Optionally and preferably, a sensor  116  of any type known in the art for indicating the presence of the rod  103  within the block may be utilized. This could, for example, be a contact sensor or a light sensor.  
         [0038]    And, as noted above and illustrated in FIG. 5, preferably two blocks  101  are rotatably attached to the support structure  108  and are located at such a distance from one another that the aperture  102  in one block  101  will be at one of the points of minimum thickness in the varying cycle of thickness of the rod  103  when the aperture  102  in the other block  101  is at one of the points of maximum thickness of the rod  103 .  
         [0039]    The Restraint of the present invention can consist solely of a lap retainer  201 .  
         [0040]    The lap retainer  201  has a first end  202  of a lap bar  203  attached to the second end  115  of the rod  103  at such an angle that the lap bar can retain a person in a seat to which a support structure  108  of the locking apparatus has been attached. Pushing the lap bar  203  generally toward the support structure  108  forces the rod  103  farther into the aperture  102  of the block or blocks  101 , thereby securing a person in a seat to which the lap retainer  201  has been attached.  
         [0041]    In order further to secure a person in a seat, a second end  501  of the lap bar  203  is, as illustrated in FIG. 6, preferably angled so that such second end  501  is generally parallel to the rod  103 .  
         [0042]    In order to release the rod  103  and permit the lap retainer  201  to be pulled farther away from the support structure  108  and, consequently, allow a person to exit from the seat, a sheathing  204  of a sheathed cable  205  is, as shown in FIG. 5, attached to the support structure  108  while the cable  206  is connected to a first end  207  of a lever arm  208  slidably mounted on the support structure  108  and connected to the block  101  or blocks  101  near the second end  109  of the block  101  or blocks  101  so that when the cable  206  pulls such lever arm  208 , the biasing of the block  101  or blocks  101  is reduced, allowing the rod  103  to be removed. (Of course, the cable  206  could be connected to a second end  209  of the lever arm  208  so that when the cable  206  pushes the lever arm  208 , the biasing of the block  101  or blocks  101  would be reduced.) Preferably, the connection of the lever arm  208  to the block  101  or blocks  101  is releasable; and a spring  301  or the like having a first end  302  attached to the support structure  108  and a second end  303  pushing against the lever arm  208  (which lever arm  208  has a surface  304  generally perpendicular to the length of the lever arm  208  in order to accept the pushing of the spring  301  or the like) maintains the lever arm  208  apart from the block  101  or blocks  101  until the cable  206  pulls the lever arm  208 .  
         [0043]    Optionally, the sheathed cable  205  can be replaced by a gas (preferably, air) actuator, designated herein as the “block actuator” which has a piston slidably mounted within a housing from which a rod, designated herein as the “block actuator rod,” exits, with a first end of the block actuator rod being connected to the piston within the block acutator and the second end of the block actuator rod being connected to the first end  207  of the lever arm  208 . The housing of the block actuator is attached to the support structure  108 . Depending on which side of the piston that the gas is injected through a valve into the housing, the block actuator rod can either push or pull the lever arm  208  to reduce biasing on the block  101  or blocks  101 .  
         [0044]    Preferably, a means for exerting a force away from the support structure  108  and generally toward the first end  202  of the lap bar  203 , preferably a gas cylinder  210  having a first end  211  of a cylinder rod  212  attached to a piston  213  slidably mounted within a bore  214  of the housing  215  of the gas cylinder  210  and containing pressurized gas on a side  216  of the piston  213  opposite to the side  217  on which the cylinder rod  212  is located, is also directly or indirectly connected to the support structure  108  and to the lap bar  203 . In the case of the gas cylinder  210 , the housing  215  is connected directly or indirectly to the support structure  108 ; and a second end  218  of the cylinder rod  212  is attached to the lap bar  203 . Alternatively, of course, the housing  215  can be connected to the lap bar  203  with the second end  218  of the cylinder rod  212  being directly or indirectly connected to the support structure  108 .  
         [0045]    Optionally, the gas cylinder  210  can be replaced with a a gas (preferably, air) actuator, designated herein as the “extension actuator,” which has a piston slidably mounted within a housing from which a rod, designated herein as the “extension actuator rod,” exits, with a first end of the extension actuator rod being connected to the piston within the extension actuator and the second end of the extension actuator rod being attached to the lap bar  203 . The housing for the extension actuator is attached to the support structure  108 . Injecting gas through a valve into the housing on the side of the piston to which the extension actuator rod is attached will cause the lap bar  203  to be pulled closer to the support structure  108 , and injecting gas through a valve into the housing on the side of the piston opposite to the side to which the extension actuator rod is attached will cause the lap bar  203  to move away from the support structure  108 . (Of course, the connections of the housing and the extension actuator rod can be reversed, thereby causing the movement just described to be reversed.)  
         [0046]    Also preferably, the lap bar  203  is rotatable (in either the yaw axis or the roll axis, but not necessarily both, with respect to the serrated rod  103 ) so that, in addition to being able to be pushed generally away from the support structure  108  to facilitate a person entering or leaving a seat to which the support structure  108  has been attached, the lap bar  203  can be rotated to create an even clearer path for such a person.  
         [0047]    To make the lap bar  203  rotatable, the first end  202  of the lap bar  203  is rotatably connected to a hinge  219 ; and the second end  115  of the serrated rod  103  is attached to the hinge  219 . In this embodiment, the means for exerting a force away from the support structure  108 , preferably the second end  218  of the cylinder rod  212 , is also directly or indirectly connected to the hinge  219 , rather than to the lap bar  203 .  
         [0048]    Also, as depicted in FIG. 7, when the lap bar  203  is rotatable, one or more plugs  220  are biased by one or more springs  221  or the like toward the first end  202  of the lap bar  203 , which first end  202  contains a cavity  222  for each plug  220  shaped to accommodate such plug  220  and located so that each such plug  220  can enter such cavity  222  only when the lap bar  203  is at the desired angle, with respect to the serrated rod  103 , to retain a person in a seat to which the support structure  108  has been attached.  
         [0049]    Once the plugs  220  have entered the cavities  222 , the plugs  220  must, of course, be removed from the cavities  222 , to permit rotation of the lap bar  203 . To facilitate such removal, a stop  223  having an aperture  224  is directly or indirectly connected to the support structure  108 . A release rod  225  has a first segment  226  designed to pass through the aperture  224  and has a second segment  227 , which second segment  227  is preferably split into as many sections  228  as there are plugs  220 . The first segment  226  has an outward projection  229  preferably near a first end  230  of such first segment and necessarily on the side  231  of the stop  223  opposite to the side  232  on which the second segment  227  is located. (For purposes of this patent application, aperture  224  may be either a single aperture or multiple apertures; and release rod  225  includes both a single rod with a split second segment  227  as explained above and also a number of rods equal to the number of plugs with the first segment  226  of each rod passing through one and only one of the apertures  224  in the stop  223 , with no aperture  224  containing more than a single first segment  226 , and with the second segment  227  of each of such rods not being split.) Moreover, preferably, the release rod  225  is telescoping in order to limit the distance that the first end  230  of the first segment  226  of the release rod  225  must extend beyond the stop  223  on the side  231  on which the outward projection  229  is located. In fact, when the release rod  225  is telescoping, the first end  230  of the first segment  226  of the release rod  225  can simply be attached to the stop  223 ; then no aperture  224  is necessary in the stop  223 .  
         [0050]    A first end  232  of each second segment  227  is attached to one or more plugs  220 . It is essential that each plug  220  be attached to a second segment  227 . Preferably, but not necessarily, however, a given plug  220  will be connected only to one second segment  227  of a release rod  225  having a non-split second segment  227  or only to one section  228  of a release rod  225  having a split second segment  227 .  
         [0051]    A simple example and preferred technique for making the release rod  225  telescoping is as follows:  
         [0052]    An outward projection  233  is attached to each second segment  227  near a second end  234  of each second segment  227 . Similarly, an outward projection  234  is attached to each first segment  226  near a second end  235  of each first segment  226 . A plate  236  has a sufficient number of apertures  237  for each first segment  226  and each second segment  227  with each aperture  237  having a diameter  238  larger than the cross-sectional width of a segment  226 ,  227  which passes through such aperture  237 . The plate  236  is situated so that it is between the outward projections  233  of the first segment  226  or segments  226  and the outward projections  234  of the second segment  227  or segments  227 .  
         [0053]    The length of the first segment  226  or segments  226  and the length of the second segment  227  or segments  227  is selected such that when the rod  103  has reached its maximum desired extension from the block  101  or blocks  101 , the stop  223  will cause the release rod  225  or release rods  225  to pull each plug  220  from each cavity  222 .  
         [0054]    Optionally, rather than having the release rod  225 , a gas (preferably, air) actuator, designated herein as the “release actuator,” which has a piston slidably mounted within a housing from which a rod, designated herein as the “release actuator rod,” exits, with a first end of the release actuator rod being connected to the piston within the release acutator and the second end of the release actuator rod being connected to each plug  220 . The housing for the release actuator is attached to the hinge  219  in such a manner that each plug  220  will be pulled from its respective cavity  222  as the first end of the release 4  actuator rod is moved farther into the release actuator housing. (Of course, a separate release actuator could be used for each plug  220 .) Injecting gas through a valve into the housing on the side of the piston to which the release actuator rod is attached will cause each plug  220  to be pulled from each cavity  222 .  
         [0055]    The Restraint also preferably has the ability to maintain the rod  103  at its maximum desired extension from the block  101  or blocks  101 .  
         [0056]    A plate  239  having an aperture  240  is attached rigidly directly or indirectly to the support structure  108 . A slide  241  is slidably mounted to the rod  103  and oriented such that a spring  242  termed the “slide spring”  242  or the like attached to the slide  241  urges a first end  242  of the slide  241  toward the plate  239 . The aperture  240  and the slide  241  are sized and positioned so that when the rod  103  is at its maximum desired extension from the block  101  or blocks  101 , the aperture  240  and the slide  241  are sufficiently aligned that the first end  242  of the slide  241  enters the aperture  240 . Optionally, rather than having an aperture  240 , the plate  239  could simply end at the same point as the aperture  240  is located. Otherwise, the plate  239  is constructed to be beside the slide  241  throughout the movement of the rod  103 .  
         [0057]    Furthermore, a first end  243  of a cable  244  is attached to any portion of the lap bar  203  which moves farther from the slide  241  as the lap bar  203  is rotated toward the desired angle, with respect to the rod  103 , to retain a person in a seat to which the support structure  108  has been attached. A second end  245  of the cable  244  is connected to a second end  246  of the slide  241 . Intermediate between the first end  243  of the cable  244  and the second end  245  of the cable  244  is a device for changing the direction of a force  247 , preferably a pulley  247 , oriented such that as the lap bar  203  is rotated toward the desire angle, with respect to the rod  103 , to retain a person in a seat to which the support structure  108  has been attached, the cable  244  pulls the slide  241  from the aperture  240 , thereby permitting the rod  103  to be pushed farther into the block  101  or blocks  101 . Of course, the length of the cable  244  is selected such that the slide  241  will remain in the aperture  240  until the lap bar  203  is rotated but not after the lap bar  203  has been rotated.  
         [0058]    Preferably, an inner sleeve  248  is slidably mounted within an outer sleeve  249 .  
         [0059]    When these sleeves  248 ,  249  are employed, the first end  202  of a non-rotatable lap bar  203  is connected to the inner sleeve  248 , preferably near a first end  250  of such inner sleeve  248 . rather than being connected directly to the second end  115  of the rod  103 ; the second end  115  of the rod  103  is connected to the inner sleeve  248 ; and the support structure  108  is connected the outer sleeve  248 , which outer sleeve  249  is to be attached to a seat when the lap retainer  201  is used.  
         [0060]    The means for exerting a force away from the support structure  108  is connected to both the inner sleeve  248  and the outer sleeve  249 . In the case of a gas cylinder  210 , the housing  215  is, preferably, connected to the outer sleeve  248 ; and the second end  218  of the cylinder rod  212  is, preferably, attached to the inner sleeve  249 . (Of course, the lap retainer  201  will function properly if, instead, the housing  215  is connected to the inner sleeve  249 ; and the second end  218  of the cylinder rod  212  is attached to the outer sleeve  248 . In fact, the lap retainer  201  will function properly if everything designated herein as being connected to, or constituting a part of, the inner sleeve  248  is connected to, or constitutes a part of, the outer sleeve  249  and everything designated herein as being attached to, or constituting a part of, the outer sleeve  249  is connected to, or constitutes a part of, the inner sleeve  248 .)  
         [0061]    When sleeves  248 ,  249  are utilized with a lap bar  203  that is rotatable, connections are the same as described above for the non-rotatable lap bar except that first end  202  of the lap bar  203  is rotatably connected to a hinge  219 ; and the hinge  219  is connected to the inner sleeve  248 , preferably near the first end  250  of such inner sleeve  248 . (Also, the second end  218  of the cylinder rod  212  or the housing  215  may continue to be connected to the hinge  219 , rather than to the inner sleeve  249 , as also may be the extension actuator housing or the second end of the extension actuator rod.)  
         [0062]    In all cases when sleeves  248 ,  249  are used, a second end  251  of the inner sleeve  248  and a first end  252  of the end of the outer sleeve  249  are substantially open. Since, preferably, the inner sleeve  248  slides into the outer sleeve  249 , this dictates that the first end  252  of the outer sleeve  249  be open. The stop  223  is preferably a second end  253  of the outer sleeve  249 . Furthermore, the plate  239  is a first side  254  of the outer sleeve  249 . And the slide  242  is slidably mounted to a first wall  255  of the inner sleeve  248 , which first wall  255  slides adjacent to the first side  254  of the outer sleeve  249  and contains an aperture  256  that is sized and positioned so that when the rod  103  is at its maximum desired extension from the block  101  or blocks  101 , the aperture  256  is sufficiently aligned with the aperture  240  in the first side  254  of the outer sleeve  249  that the first end  242  of the slide  241  enters aperture  256  and aperture  240 .  
         [0063]    Alternate exemplary versions of the rod lock  1  are any type of ratchet lock that is well known in the art and a hydraulic lock  257 .  
         [0064]    The hydraulic lock  257  has, as portrayed in FIG. 10, a housing  258  having a bore  259  within which a piston  260  is slidably mounted. The housing  258  has a first end  261  containing an aperture  262  through which the rod  103  passes before having the first end  105  of the rod  103  attached to the piston  260 . Of course, the second end  115  of the rod is attached just as described above when the locking apparatus serves as the rod lock  1 .  
         [0065]    Attached to the housing  258  at or nearer the first end  261  of the housing  258  than the piston  260  will ever be and communicating with the bore  259  of the housing  258  is a first end  262  of a tube  263 . Attached to the housing  258  at or nearer the second end  264  of the housing  258  than the piston  260  will ever be and communicating with the bore  259  of the housing  258  is a second end  265  of the tube  263 . In the tube  263  at a location intermediate between the first end  262  of the tube  263  and the second end  265  of the tube  263  is a valve  266 .  
         [0066]    Hydraulic fluid cannot flow through or around the piston  260 . Therefore, the only way for hydraulic fluid to flow from one end  261 ,  264  of the housing  258  to the other end  264 ,  261  of the housing  258  is through the tube  263 . This can occur when the valve  266  is open but not when the valve  266  is closed. Thus, because of the incompressibility of hydraulic fluid, the piston  260  and, consequently, the rod  103  can move only when the valve  266  is open.  
         [0067]    A preferred option to accompany any embodiment of the lap retainer  201  is a shoulder retainer  401 .  
         [0068]    The shoulder retainer  401  has, as shown in FIG. 8 and FIG. 9, a rod lock  1 . The rod lock  1  can be any of the versions of the rod lock  1  discussed with respect to the lap retainer  201 , and the structure of such versions, including the means for releasing the rod  103 , is virtually identical to that described above with respect to the lap retainer  201 .  
         [0069]    A first end  105  of a rod  103  is inserted into the rod lock  1 . A shoulder bar  402  is either directly or indirectly attached to the second end  115  of the rod  103 . The shoulder bar  402  consists of two or more forwardly and downwardly extending projections  403  shaped to fit around a person&#39;s left and right shoulders for retaining such shoulders in a seat to which the rod lock  1  has been attached and oriented so that movement of the rod  103  will tighten or loosen such retention.  
         [0070]    Also, preferably, as with the lap retainer  201 , the housing  215  of a gas cylinder  210  is connected directly or indirectly to the rod lock  1 ; and a second end  218  of the cylinder rod  212  is attached directly or indirectly to the shoulder bar  402 . (Again, as was the case with the lap retainer  201 , these connections can be reversed; and the gas cylinder  210  can be replaced with an extension actuator.)  
         [0071]    Preferably, a C-channel  404  is to have the side  405  opposite to the longitudinal slot  406  attached to the back of a seat. A wheeled cart  407  has two or more wheels  408  on a first side  409  of the cart  407  and two or more wheels on a second side  410  of the cart  407  with the wheels  408  spaced so that some wheels  408  will be within the C-channel  404  while other wheels  408  will be outside the C-channel  404 . The second end  115  of the rod  103  is attached to the cart  407 , the shoulder bar  402  is attached to the cart  407 , and the second end  218  of the cylinder rod  212  is attached to the cart  407 . The rod lock  1  and the housing  215  of the gas cylinder  210  are connected to the C-channel  404 .