Abstract:
A stowage magazine is provided for securing a can of ammunition rounds. The magazine includes a frame having lateral sides that define a space for the can; a hinge mechanism connecting to the lateral sides; and a door connecting to the mechanism. The door provides and restricts access to the space in respective open and closed positions. The door is openable along an axial direction to provide an operational surface. The mechanism avoids lateral obstruction beyond the door&#39;s surface.

Description:
STATEMENT OF GOVERNMENT INTEREST 
     The invention described was made in the performance of official duties by one or more employees of the Department of the Navy, and thus, the invention herein may be manufactured, used or licensed by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor. 
    
    
     CROSS REFERENCE TO RELATED APPLICATION 
     The invention is related to and incorporates by reference in its entirety an application for U.S. Patent titled “Slider-Hinge Door” and assigned application Ser. No. 13/068,908. 
     BACKGROUND 
     The invention relates generally to slider-hinge doors/ship-board magazines that contain ammunition. In particular, this invention relates to a ready service magazine that facilitates proximate access to ammunition while complying with relevant safety requirements. 
     The United States Navy has commissioned two class prototypes for a Littoral Combat Ship (LCS) intended for close shore fire support. In particular, the lead ships for these classes are the steel planing monohull U.S.S. Freedom (LCS-1) designed by Lockheed Martin, and the aluminum trimaran U.S.S. Independence (LCS-2) designed by General Dynamics. Both classes can be reconfigured with interchangeable weapons modules for select plug-and-fight missions. Follow-on ships in the Freedom class include U.S.S. Fort Worth (LCS-3), U.S.S. Milwaukee (LCS-5) and U.S.S. Detroit (LCS-7). Follow-on ships in the Independence class include U.S.S. Coronado (LCS-4), U.S.S. Jackson (LCS-6) and U.S.S. Montgomery (LCS-8). 
     The Gun Mission Module (GMM) as an example for the surface warfare module package includes two turret-mounted, axis-stabilized chain guns that can fire up to 200 rounds per minute of 30×173 mm ammunition, and can hold 800 rounds. Uniformed Navy personnel operate in highly confined spaces, including below deck. The GMM chain gun protrudes above deck from a module cover, below which personnel can supply ammunition from storage containers. Conventionally, such containers are disposed in a location requiring such ammunition either to be linked together absent adequate platform and/or to be carried to the combat firing platform some significant distance from its stowage location. 
     SUMMARY 
     Conventional ammunition stowage magazines yield disadvantages addressed by various exemplary embodiments of the present invention. In particular, these embodiments provide a stowage magazine for securing a can of ammunition rounds. 
     The magazine includes a frame having lateral sides that define a space for the can; a hinge mechanism connecting to the lateral sides; and a door connecting to the mechanism. The door provides and restricts access to the space in respective open and closed positions. The door is openable along an axial direction to provide an operational surface. The mechanism avoids lateral obstruction beyond the door&#39;s surface. The frame can suspend lanyards to restrain the can even with the door in open position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and various other features and aspects of various exemplary embodiments will be readily understood with reference to the following detailed description taken in conjunction with the accompanying drawings, in which like or similar numbers are used throughout, and in which: 
         FIGS. 1A and 1B  are isometric assembly views of an ammunition magazine module; 
         FIG. 2A  is an isometric exploded view of components for the ammunition magazine module; 
         FIG. 2B  is an isometric component view of a door panel; 
         FIGS. 3A and 3B  are respective isometric views of a magazine frame and an ammunition can; 
         FIGS. 4A and 4B  are respectively isometric and plan assembly views of a ready service magazine; 
         FIG. 5  is an elevation assembly view of the ready service magazine; 
         FIGS. 6A and 6B  are elevation detail views of components of the ready service magazine; 
         FIGS. 7A and 7B  are respectively isometric and elevation assembly views of the ready service magazine; 
         FIG. 8  is an isometric assembly view of an LCS GMM stowage frame; and 
         FIGS. 9A and 9B  are isometric assembly and exploded views of the LCS GMM. 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description of exemplary embodiments of the invention, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific exemplary embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments may be utilized, and logical, mechanical, and other changes may be made without departing from the spirit or scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims. 
       FIG. 1A  shows an isometric assembly view  100  of an ammunition magazine module in closed configuration. For orientation convention, depth, width and height can be denoted by arrows for axial  110  (aft-to-fore), lateral  120  (port-to-starboard) and vertical  130  (bottom-to-top) directions. The magazine  140  includes a rectangular container  150  flanked by a hinge-rail assembly  160  and accessible by a hatch or door  170  accessible by a handle  175 .  FIG. 1B  shows an isometric assembly view  180  of the modular ammunition magazine  140  in open configuration as indicated with the door  170  pulled down by the handle  175  to reveal an internal storage chamber  190 . 
     The door  170  represents a front-load configuration that travels axially fore and aft. Artisans of ordinary skill will recognize that this movement can also apply to a top-load configuration for a door that travels vertically up and down. Depending on orientation, the terms “fore” and “aft” can be interpreted as directions of door&#39;s motion for either opening configuration that are substantially parallel to the sides of the container  150 . 
       FIG. 2A  shows an isometric exploded view  200  of components for the magazine module  140 . The hinge-rail assembly  160  comprises armature components  210  mounted to the external port and starboard sides of the container  150 . The components  210  include an elbow bar  220 , a slider  230 , a slide rail  240 , a first three-point hinge  250 , and a second two-point hinge  260 . Button pins  270  protrude laterally from the container  150  on which the first hinge  250  and second  260  hinge pivot. The elbow bar  220  attaches to the slider  230  to traverse fore and aft along the slide rail  240 . Button pins  275  and protruding flanges  280  extend from the lateral ends of the door  170 .  FIG. 2B  shows an isometric view  290  of the door  170 . The upper and lower pins  270  insert into ends of the respective second and first hinges  260  and  250 . The upper and lower pins  275  insert into ends of the respective first and second hinges  250  and  260 . 
       FIG. 3A  shows an isometric view  300  of the magazine&#39;s framework, and  FIG. 3B  shows an isometric view  310  of an ammunition can for 30 mm rounds. The magazine includes a steel container frame  320  comprising a stack pair of containers  150  mounted on a floor base  330  shown within substantially the same directional orientation as container assembly view  100 . The frame  320  defines interior spaces  340  separated by dividers  350  and  360 . A strut  370  attaching to the lateral sides of the frame  320  provide mounts for the rail  240 . 
     A typical 30 mm ammunition can  380  slides into one space  340  for stowage. For the container frame shown  320 , the spaces  340  can hold a total of eight cans  380 . Each can  380  holds two belts of fifteen linked 30 mm rounds and weighs about 80 pounds-mass. Alternate designs can provide for more or fewer ammunition containers of sundry dimensions. 
       FIGS. 4A and 4B  respectively show an isometric assembly view  400  and a plan assembly view  410  of a modular Ready Service Magazine  420  for ammunition stowage. A pair of upper and lower containers  150  stacks vertically together as the frame  320  onto and above the base  330 . A security bar  430  locks the doors  170  in the closed position when not in use to inhibit unauthorized opening, particularly from sudden lateral ship movement. 
     Typical dimensions for the magazine  420  include length (along the lateral direction  120 ) of 44.0 inches, height (vertical direction  130 ) of 37.0 inches and width (axial direction  110 ) of 20.0 inches. The door  170  has corresponding length, width and thickness of 42.75 inches, 15.75 inches and ⅞ inch with a weight of 44 pounds-mass. The door&#39;s steel panel surface incorporates a perpendicular mesh of steel strips for structural support of ammunition disposed thereon. Artisans of ordinary skill will recognize that these dimensions are exemplary only and not limiting. 
     A thermometer  440  above the upper container  150  monitors temperature of the magazine&#39;s environment within the spaces  340 . A label plate  450  provides appropriate identification of the magazine  320  and its contents. The magazine  420  incorporates features suitable for both an ammunition magazine (e.g., provisions for accessible workspace, thermal insulation, ventilation, and a sprinkling system) and a storage locker (e.g., possession of minimal footprint, and securable access doors). 
       FIG. 5  shows an elevation assembly view  500  of the magazine  420  from the fore end with the doors  170  removed. Each container  150  includes a hanger guide  510  and a hook eyelet  520  to secure outer and inner retaining lanyards  530 ,  540 . The eyelet  520  includes a detail view  550  described below. The lanyards  530 ,  540  provide restraints for the can  380  from crashing or slamming into the operating sailor as the ship rolls or pitches at sea while the door  170  remains open. A sprinkler-valve  560  supported by a column  570  attaches to the top of the magazine  420  for supplying fire retardant (e.g., water) in response to combustion, or else ventilation in the event of pressure from gas accumulation. The magazine  420  may also be equipped with sprinklers or alternate fire suppressant systems to retard blazes therein. 
       FIGS. 6A and 6B  show elevation detail views  600  and  610  of components related to the hinge components  210  and the eyelet  520 . The view  600  shows a lateral side of the magazine  420  from starboard looking port. The view  610  shows the front of the magazine  320  from the front looking aft. In particular, the first hinge  250  features a pivot joint  620  connecting the first hinge  250  to the door  170  at the upper button pin  275 . Rollers on the slider  230  enable the elbow  220  to axially translate along the rail  240 . These motions open the door  170  from its closed position against the container. 
     A detail features a dog bolt assembly  630  including a rotatable handle  640  that can pivots on a swing hinge  650  attached to either side of each container  150 . With the door  170  closed, the handle  640  latches between the flanges  280  to preclude opening, being further secured by the security bar  430 . Note that the handle  640  can rotate on either or both longitudinal and hinge axes for quick release or engagement. The dog-latch assembly  630  latches the flanges  280  on the door  170 . The swing hinge  650  enables the handle  640  to be swung laterally away from the flanges  280  to release the door  170  for opening. The elbow bar  220  features an end cap  660 . A grounding boss  670  provides an attachment to electrically ground each module  140 . The eyelet  520  connects the inner lanyards  540  connected by the lanyard end retainers  680 . 
     Conventional techniques for supporting a drop-door involve top surface hinges or cables as commonly used in hatches for ovens or troop trans-ports to augment hinges that may support the door as a resting surface. Other conventional techniques involve manually pulling out a slider to support the drop door. Typically, these flanking sliders and cables impede lateral access beyond the door&#39;s opened surface, thereby blocking transport of items, such as ammunition rounds. 
     In various exemplary embodiments, the door  170  attaches at the lower and upper button pins  275  respectively to the second hinge  260  and the first hinge  250 , the latter demarcated as the joint  620 . Both hinges  260  and  250  connect to the container  150  respectively at the upper and lower button pins  270  to form a four-bar linkage assembly on each of the port and starboard sides. The slide rail  240  attaches to the container  150 , which houses the slider  230 . The elbow bar  220  attaches to the slider  230 . 
     The top of the first hinge  250  is equipped with a roller caster that rides inside a vertical slot of the elbow bar  220  forms a scotch yoke between the slide rail  240 , the elbow bar  220  and the slider  230 . The hinge-rail assembly  160  provides the advantages of providing a work surface that can be completely unobtrusive on both the top and at the port and starboard sides. The hinge-rail assembly  160  also enables the automatic reposition of the sliders  230  based purely on motion of the door  170 , such as by a scotch yoke (for converting between circular and linear motions), without the use of cables or gears. 
       FIGS. 7A and 7B  respectively show an isometric assembly view  700  and an elevation assembly view  710  of the magazine  420  illustrated with the doors  170  hinged open to reveal the cans  380  restrained by the lanyards  530  and  540 . The flanges  280  on each door  170  rest on the elbow bars  220  to provide a flat table work surface  720  in front of the magazine  420 . The door&#39;s surface  720  supports 30 mm ammunition rounds  730  concatenated together for feeding into the chain gun by metal links  740  that may be assembled by sailors. For the configuration produced, the door  170  supported by the elbow  120  can support a load exceeding 80 pounds-mass. 
       FIG. 8  shows an isometric assembly view  800  of a pair of magazines  420  within a ship hold for containing the Gun Mission Module (GMM). The magazines  420  are contained within and covered by a storage frame  810  that includes a cutout region  820  for the gun platform, as well as an ammunition feed chute  830  to receive rounds  730  stored in the cans  380  within the spaces  310 .  FIGS. 9A and 9B  respectively show an isometric assembly view  900  and an isometric exploded view  910  of a GMM  920  installed in a ship hold  930 . 
     The GMM  920  includes a mid-foundation frame  940  and an upper mount frame  945  on which the turret  950  is disposed. The frames  940  and  945  are covered by a gun cover  960  connected to the hold  930  by a barbette  965 . The mid frame  940  rests on a foundation frame  970 . The storage frame  810  external to the mid frame  940 , as demarcated by the cutout  820 , contain magazines  420  on the foundation frame  970 . 
     Various exemplary embodiments of the ammunition magazine  420  can be employed as an LCS Gun Mission Module (GMM) Ready Service Magazine  420  in compliance with NAVSEA OP-4. The nature of the modular weapon system, such as the GMM, poses unique requirements on the ammo storage area, which must satisfy many requirements of both a traditional Ready Service Magazine and a Ready Service Locker. The exemplary Ready Service Magazine  420  combines elements of both the magazine and locker to provide a a working space, similar to a traditional magazine, in the form of fold down doors for linking and de-linking ammo, while maintaining a locker sized footprint located in proximity to the weapon platform to be served. 
     Some missile storage rooms containing automatic handling equipment also serve as conventional primary magazines. Such a magazine constitutes actually a walk-in chamber with many requirements that are non-applicable for a modular weapon system including such features such as thermal insulation. 
     Conventional lockers are often provided for stowage of special types of ammunition and ammunition components such as detonators, pyrotechnics, and chemicals. These are frequently located on the weather deck to be conveniently accessible for the weapon to be served. White sunshields may be required when such lockers face exposure to external elements. Various requirements may be imposed depending on usage: NAVSEASYSCOM Drawing 804-1360106 for topside lockers attached to a deck or bulkhead, NAVSHIPS Drawing 804-6397302 for stowage of thermite grenades. 
     Lockers for pyrotechnic and incendiary ammunition, such as parachute flares and thermite grenades, include manual jettison capability in case of fire in the vicinity. Being located below the weather deck, the exemplary Ready Service Magazine  420  does not require the sunshield. 
     A positive locking device, such as the security bar  430  can be provided to prevent inadvertent actuation of any jettison mechanism installed in the magazine  420 . The support arm for the armature components  210  enable avoidance of contact with intended contents when the doors  170  are closed. 
     The LCS GMM ready service magazine  420 , divided into upper and lower sections with each containing four ammunition cans  380 , can be operated as follows: An operator (e.g., sailor) unlocks the security bar  430  from the magazine  420 . The operator opens the door  170  by grasping the handle  175  to pull forward. The operator unlatches the retaining lanyards  530  and/or  540  for the compartment to be accessed. The operator pulls an ammunition can  380  forward onto the work surface  720  of the door  170 . The operator pulls the ammunition can  380  and connects rounds  730  together by associated links  740  on the door&#39;s work surface  720 . The magazine  420  has the advantage of providing an unobstructed working surface  720  and stowage spaces  340  in a small footprint necessary for a modular system. 
     While certain features of the embodiments of the invention have been illustrated as described herein, many modifications, substitutions, changes and equivalents will now occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the embodiments.