Abstract:
A coupling device for connecting a filter element to a filter conduit has male and female couplings each having a passageway for fluid. The male coupling is secured to the filter conduit and has at least two radially projecting lugs. The female coupling is secured to the filter element and has at least two latching tabs for engaging the lugs. A spring is operatively mounted on the male coupling and interferes with the radially projecting lugs. The spring is disposed so as to engage at least one latching tab when the male and female couplings are moved toward each other. The spring urges the latching tabs to rotate in a first angular direction thereby causing the tab to latch to a lug of the male coupling.

Description:
TECHNICAL FIELD  
         [0001]    The invention relates generally to a filter cartridge for a filter vessel in a fluid purification system, and more particularly to a coupling device used to connect a replaceable filter cartridge to an outlet tube in a filter vessel for purification of radioactive or other hazardous fluids.  
         BACKGROUND OF THE INVENTION  
         [0002]    Power plants and other facilities with fluid purification processes frequently have used filter tanks or filter vessels to purify a variety of different liquids or gases, such as fluid fossil fuels, steam or water. Such filter vessels have an inlet supplying a fluid to a main filtration chamber holding a number of tubular filters. Long tubes within the filter vessel support and act as the core for the tubular filters. These long tubes extend from a tube sheet that separates the main chamber from a plenum for holding purified fluid. An outlet leads from the plenum to the exterior of the filter vessel.  
           [0003]    In conventional practice, on the opposite end of the filters from the tube sheet, separate filter mount assemblies secure the filters to the tubes while sealing that end of the tube. The conventional filter mount assemblies contain numerous parts, which frequently fall into the filter vessel during disassembly of the mount assembly to replace the filters. Parts falling into the vessel must be removed to prevent damage to filter elements caused by motion of the loose parts during service flow. If loose parts cannot be readily located and removed with suitable “fishing” tools, filter elements must be removed to permit access to the vessel to retrieve the loose parts. U.S. Pat. No. 5,667,679 to Bozenmayer et al. attempts to solve this problem by providing a filter mount assembly that may be removed quickly without losing parts. This design, however, uses stainless steel parts that are difficult to dispose or recycle when radioactive, which condition may obtain in nuclear power plants.  
           [0004]    Another problem associated with conventional filter mount assemblies relates to the ease of installation and removal. Rapid installation and removal of filter elements in radioactive steam systems or other hazardous environments is highly desirable to minimize worker exposure.  
           [0005]    Referring to FIG. 1, another conventional filter vessel  100  has an inlet  102  that delivers unpurified, typically pressurized, fluids to a main chamber  104 . The arrows F indicate direction of flow for the fluid during normal operations.  
           [0006]    The fluid enters replaceable filter cartridges  106 , as known in the art, and through known tubular filters contained thereby that remove unwanted particulate or foreign matter. The purified fluid then flows downward through tubes or pipes  108  that open up into a plenum  110 . The plenum is separated from the main chamber  104  by a stainless steel or a carbon steel false bottom or tube sheet  112  conventionally welded to the tubes  108 . The fluid then exits the filter vessel  100  through an outlet  114 . Conventional filter vessels  100  typically vary in diameter from six inches to seven feet (and three foot to eight foot heights) depending on the quantity and size of filter elements contained therein. Vessels are known to accommodate anywhere from two to over 1000 filter cartridges.  
           [0007]    Some conventional filter cartridges  106  are held in place by a hold down plate  116  as known in the art. The filter cartridges  106  are single open-ended with a closed top and a protruding bolt, post, rod or other connector  118  to extend upward through a hole in the hold down plate  116  for lateral support and to maintain distances between adjacent filter cartridges. The hold down plates  116  are usually bolted to the perimeter of the vessel or secured to the bottom by long connecting rods (not shown). Either mechanism provides downward force to seal the cartridges  106  to the tube sheet  112 . Cartridges  106  that are held down by hold down plates  116  typically have a spigot that fits into holes in the tube sheet  112 , and is sealed with either a flat gasket or one or more O-rings (not shown).  
           [0008]    Some filter cartridges  106  have threaded bottoms for securing the filter cartridge to the tube sheet  112  and effecting a liquid tight seal, and these therefore do not require a hold down plate. However, threading of the filter cartridge  106  onto each of the tubes  108  requires numerous rotations of the filter cartridge  106  by a robot, hand, wrench, other special tool or automatic mechanism. The threading and unthreading of the filter cartridge  106  is a time consuming job which undesirably prolongs the worker&#39;s exposure to a hostile environment.  
           [0009]    U.S. Pat. No. 3,279,608 to Soriente et al. discloses a guide rod and hook design used to mount a filter cartridge onto a tube welded to a tube sheet such as an Aegis™ Fossil Assembly as is known in the art. The filter cartridge has a guide rod welded to a plate with an end having a hook. A coil spring and nut are used to seal the top of the filter while compressing the filter cartridge against the tube to hold it in place against an adapter threaded permanently to the tube.  
           [0010]    The upper end of the guide rod is used to attach to a positioning lattice for lateral stabilization. This design, however, still requires the unthreading of the nut to remove the filter cartridge from the tube, and the rivet hook is not considered to be of adequate strength for high pressure and highly corrosive nuclear power plant applications.  
           [0011]    Another known filter cartridge and filter vessel eliminates the need for threading the filter cartridge to a tube on a tube sheet. As shown on FIGS.  2 A- 2 D, a filter cartridge  500  has a steel adapter  502  that connects a filter  504  to a stainless steel filter vessel tube  506 . As shown in FIGS.  2 C- 2 D, a spring  508  applying forces of 50-60 pounds is located between a support ring  510  welded to the exterior of the tube  506  and two pins  512  also welded to the exterior of the tube  506 . Referring to FIGS. 2B and 2C, the adapter  502  has two opposing slots  514  (only one shown) for receiving the pins  512  and has an annular groove  516  that slides over the pins  512  as the adapter  502  is rotated about the tube  506 . Once the adapter is rotated 90°, as shown in FIG. 2D, the pins  512  are positioned in two opposing locking apertures  518 .  
           [0012]    In order to position a filter cartridge  500  on the tube  506 , the filter cartridge must be pushed downward (axially) to engage the pins  512  and spring  508 , and then rotated a full ninety degrees to place the pins  512  in the locking apertures  518 . The spring  508  biases the adapter  502  upward to hold the pins  512  against the bottoms  520  of the locking apertures  518 , which further stabilizes and secures the filter cartridge  500  on the tube  506 .  
           [0013]    In some nuclear power plant filter vessel applications, during backwashing (fluid flow in the upward direction on FIGS.  2 A- 2 D) the spring and fluid can combine to form an axial force of over  100  pounds that impacts the filter cartridge  500 . The adapter  502  must be made of steel to withstand this force, which is transmitted through the circular pins  512 . Otherwise, the high axial forces will cause the pins  512  to rip through an adapter  502  made of a weaker material, such as plastic, and disengage the filter cartridge  500  during backwashing operations.  
           [0014]    Radioactive steel hardware, however, is dangerous, difficult and expensive to handle when replacing filter cartridges. Steel hardware cannot be recycled or incinerated using present technology. Re-use of the hardware with new filter cartridges is not practical due to the amount of radiation to which the operator is exposed. For this reason alone, the hardware is often replaced rather than re-used. The discarded hardware that is disposed of as radioactive waste will incur a disposal cost that is ten times or more its initial cost.  
           [0015]    Accordingly, what is needed is an inexpensive, easy to use filter mount assembly constructed of easily and economically disposable materials.  
         SUMMARY OF THE INVENTION  
         [0016]    The present invention is directed to a coupling device for connecting a filter element to a fluid conduit. The coupling device includes a male and a female coupling member with each member having a passageway for fluid. The male coupling member has at least two radially projecting lugs. The female coupling member has at least two latching tabs that engage the radially projecting lugs of the male coupling member. A spring is operatively mounted on the male coupling member. The spring is disposed to engage at least one latching tab when the male and female coupling members are moved toward each other. The spring urges the latching tab to rotate in an axial direction thereby causing the latching tab to latch to the lug of the male coupling member.  
           [0017]    Another aspect of the present invention is directed to a fluid coupling element with a first and second coupling member formed around an axis. The second coupling member is sealably matable to the first coupling member for the transmission of fluid therethrough. The first coupling member has a free end and a sidewall with a lug extending laterally from the sidewall. The lug has a latch surface formed at an angle to the axis. The lug also has a guide surface that extends from the latch surface toward the free end of the first coupling member. The second coupling member has a sidewall that terminates in a free end. The second coupling member also has a latch tab that terminates in an enlargement portion. A means for indexing, is mounted on the first coupling member, leads the enlargement of the latch tab to the guide surface of the lug. A spring is mounted on the first coupling member and is disposed to engage the second coupling member when the first coupling member is coupled to the second coupling member. The enlargement portion of the latch tab is urged against the guide surface of the lug by the spring. The enlargement portion of the latch tab clears the second surface of the lug when the first coupling member is mated to the second coupling member. The spring rotates the enlargement portion of the latch tab relative to the axis of the first coupling member so that the enlargement portion of the latch tab abuts the latch surface of the lug after the enlargement portion of the latch tab clears the guide surface of the lug.  
           [0018]    Another aspect of the present invention is directed to a method of joining a first fluid carrying member to a second fluid carrying member so as to define a fluid path therebetween. A terminal portion of at least one latch tab of the first fluid carrying member is indexed to a guide surface of a lug extending from the sidewall of the second fluid carrying member. One of the first or second fluid carrying members is inserted into a second of the first or second fluid carrying members. The terminal portion of the latch tab is slid along the guide surface of the lug until an enlarged portion of the latch tab has moved axially farther away from the free end of the second fluid carrying member than a retaining surface of the lug. A spring is used to rotate the latch tab of the first fluid carrying member around the axis such that the enlarged portion of the latch tab becomes located adjacent the retaining surface of the lug. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]    The above mentioned and other features of this invention and the manner of obtaining them will be apparent, and the invention itself will be best understood, by reference to the following description of illustrated embodiments of the invention in conjunction with the drawings, in which like characters identify like parts and in which:  
         [0020]    [0020]FIG. 1 is a cross-sectional side view showing components of a filter vessel as known in the prior art;  
         [0021]    [0021]FIG. 2A is a cross-sectional side view of a filter cartridge to outlet tube connection as known in the art;  
         [0022]    [0022]FIG. 2B is an exploded side view of a coupling device for the filter cartridge illustrated in FIG. 2A, as known in the art;  
         [0023]    [0023]FIG. 2C is an assembled side view of the coupling device illustrated in FIG. 2A, as known in the art;  
         [0024]    [0024]FIG. 2D is an assembled side view of the coupling device illustrated in FIG. 2A, as known in the art, with an upper portion of the coupling turned ninety degrees;  
         [0025]    [0025]FIG. 3A is a cross-sectional side view showing components of a filter vessel in accordance with the present invention;  
         [0026]    [0026]FIGS. 3B is a top and side exploded part isometric, part cross-sectional view, of male and female coupling portions of the coupling device in accordance with the present invention;  
         [0027]    [0027]FIG. 4A and 4B are partially exploded views of a male coupling portion of the coupling device in accordance with the present invention;  
         [0028]    [0028]FIG. 4C is a partially exploded view of an alternative configuration of the male coupling portion of the coupling device in accordance with the present invention;  
         [0029]    [0029]FIG. 5 is a cross-sectional isometric view of the female coupling in accordance with the present invention;  
         [0030]    [0030]FIG. 6 is a top view of the female coupling in accordance with the present invention;  
         [0031]    [0031]FIG. 7 is an isometric view of a latch ring attached to the female coupling of the coupling device in accordance with the present invention; and  
         [0032]    FIGS.  8 A- 8 C are side views of the coupling device in accordance with the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0033]    Referring to FIG. 3A, a filter vessel  12  has a fluid inlet  14 , an outlet  16 , a main filtration chamber  18  and a plenum  20  separated from the main chamber by a tube sheet or false bottom  22 . While the filter vessel  12  is shown holding three filter elements or cartridges  24 , it will be appreciated that filter vessels may be designed to accommodate any number of filter cartridges depending on the particular filtration requirements of the fluid system.  
         [0034]    Each filter cartridge  24  has a top portion  26 , preferably designed to be free standing, but alternatively supported laterally and/or vertically by a hold down plate or positioning lattice  28  as known in the art. The hold down plate or positioning lattice  28  may include spaced dimples (not shown) to mate with indents (not shown) on the top portion  26  of the filter cartridges  24 , or posts or bolts (not shown) may extend from the top portion  26  to be inserted through holes in the hold down plate or positioning lattice  28  as known in the art.  
         [0035]    Each filter cartridge  24  includes a housing  29  which holds a tubular filter  30 , as known in the art, that includes yarn and/or pleated non-woven membrane surrounding a perforated core.  
         [0036]    For radioactive filtering applications it is desirable to form the housing  29  from a material which can be readily shredded and incinerated. Preferably, the housing  29  is formed from a thermoplastic material such as polypropylene which may be reinforced with glass fiber or another filler.  
         [0037]    Referring now to FIG. 3B, a coupling device  10  according to the invention mounts each filter cartridge  24  onto a steel filter conduit or tube  32  integrally formed with, or welded to, the tube sheet  22 . Each coupling device  10  includes a preferably stainless steel adapter or male coupling  34  and a non-steel adapter or female coupling  36  which is formed as part of the filter cartridge  24 . The male coupling  34  is permanently attached to the filter conduit  32 , as explained below.  
         [0038]    It will be appreciated that the male coupling  34  may be made of any corrosion-resistant material of suitable strength as long as it is compatible with the hazardous or radioactive environment of the fluid process.  
         [0039]    To facilitate disposal, the female coupling  36  may be formed of any material which is amenable to be shredded and incinerated. Preferably, the female coupling  36  is formed of a polymeric material, such as thermoplastic and thermosetting plastics, polymers and resins, that have sufficient structural strength to withstand, in the structures shown, at least 70 to 100 pounds in axial force without shearing, tearing or otherwise failing. A particularly preferred material includes injection molded polypropylene which may be reinforced.  
         [0040]    The female coupling  36  may be continuously formed with the housing  29 , or may be integrally attached thereto using any known method of attachment. For example, the female coupling  36  may be attached to the housing  29  by thermo-bonding, welding, chemical bonding, threading, pinning, or any other mechanical mechanism that provides an adequate seal between the housing  29  and the female coupling  36  while permitting the core of the filter to communicate with the core  74  of the female coupling  36 .  
         [0041]    It will be appreciated, however, when recycling or handling is not a concern, the female coupling  36  could be made of metal, such as stainless steel, as long as it is strong enough to withstand the impact of axial forces distributed by the lugs  54 .  
         [0042]    Referring to FIGS. 4A and 4B, in the preferred embodiment, the male coupling  34  has a generally cylindrical shape defining a hollow core  40  to be used as a fluid passageway and defining an axial direction or axis ‘a’. The male coupling  34  also includes a cylindrical first upper portion  42  with a free end  41  that connects to the female coupling  36 , and a second lower portion  44  that connects to the filter conduit  32 , preferably by welding or threaded connection.  
         [0043]    The inner diameters of the upper and lower portions are also different lengths to accommodate the sizes of the filter cartridge  24  and the filter conduit  32 . The filter conduit  32  comes in a range of sizes from 1″ to 6″ outer diameter, but typically is provided with approximately 1½″ outer diameter for both nuclear and fossil fuel applications, while the filter cartridges themselves are provided in the 2-2½″ outer diameter range for most applications. The upper portion  42  of the male coupling  34  typically has inner diameter of 1¼to 1½″ for filter cartridges  24  spaced within the filter vessel  12  at 3 to  3½″ centers.    
         [0044]    In the preferred configuration, lugs  54  are welded to, or more preferably integrally formed with, the exterior sidewall  50  of the male coupling  34  so that the core  40  is not blocked by any support mechanism for the lugs  54 . The lugs  54  project outwardly from the exterior sidewall  50  of the male coupling  34 , preferably at right angles to axis a. The lugs  54  include an upper surface  53 , a lower, retaining or latch surface  56 , a guide surface  58  and a sloped, angled or concavely arcuate surface  59 .  
         [0045]    While the illustrated embodiment shows lugs  54  disposed about a single plane that is orthogonal to axis a, in an alternative embodiment the lugs can occupy segments of helical paths. In this alternative embodiment, each lug  54  would tilt upward from the junction of the guide surface  58  and the latching surface  56 .  
         [0046]    It will be appreciated that while lugs  54  are shown at diametrically opposite positions, many positions at angles to the axis ‘a’ are possible. Additionally, three, four or more lugs can be used rather than just the two lugs shown.  
         [0047]    The male coupling  34  is fitted with one or more springs  65 , preferably torsional, that are mounted to respective mounting posts or shanks  55  which extend from the exterior sidewall  50  of the male coupling  34  in a direction generally normal to the axis ‘a’. See FIGS. 4A and 4B. Spring  65  defines an opening  67  which fits snugly into shank  55 . In an assembled condition, the spring  65  is press fit onto the shank  55 .  
         [0048]    According to the embodiment illustrated in FIG. 4A, the shank  55  may be of circular cross-section and include a through hole or channel  57  formed proximate a terminal end thereof. The spring  65  may include a terminal loop end portion  69  adapted to snugly fit within the through channel  57 . In this manner the through channel  57  and loop end portion  69  cooperatively prevent rotation of the spring  65  relative to the shank  55 .  
         [0049]    The shanks  55  are axially positioned to be near the lugs  54  such that each spring  65  contacts a lug  54  when installed on a shank  55 . The spring  65  includes an elongated sloped portion  65   a  which, as will be described below, aids in orienting the female coupling  36  relative to the male coupling  34 . The spring  65  also includes a free end  65   b . As shown in FIG. 3B, when the spring  65  is positioned on the shank  55 , a gap or indexing notch  60  is formed between the spring  65  and the guide surface  58  of each lug  54 .  
         [0050]    Alternatively, as illustrated in FIG. 4C, the shank has a non-circular cross-section to inhibit rotation of the spring relative to the shank.  
         [0051]    Referring now to FIGS.  5 - 7 , in the illustrated embodiment the female coupling  36  has a preferably cylindrical body  70  with an interior cylindrical surface or side wall  72  that ends in a free end  71  and defines a hollow core  74  that provides a passageway for fluid and defines an axial direction or second axis ‘a’ in the general direction of flow through the female coupling  36 .  
         [0052]    The female coupling  36  features a latch ring  76  having a pair of preferably integrally formed latching tabs  78  which are sized to engage the lugs  54  (see FIG. 7). According to a preferred embodiment, the latch ring  76  is continuously and integrally formed with the female coupling  36  from the same material used to form the female coupling  36 . Alternatively, the latch ring  76  may be formed separately from the female coupling  36 , and press fit, glued or otherwise bonded to the hollow core  74  of the female coupling  36 .  
         [0053]    The latching tabs  78  are configured to engage and partially surround the lugs  54 . The latching tabs  78  include an enlargement portion  84  defined by a bottom sloped surface  79 , a side surface  80  and a top surfaces  81 . The latching tabs  78  also include a leg  83  that extends downwardly from the latch ring  76  into the enlargement portion  84  of each latching tab  78 . The top surfaces  81  of the latching tabs  78  are configured to engage the retaining or latching surfaces  56  of the lugs  54 , and a lower surface  77  of the latching ring  76  engages an upper surfaces  53  of the lugs  54 .  
         [0054]    The retaining surface  56  of the lugs  54  may be formed at a slight angle relative to horizontal, in which case the top surface  81  of the latching tabs  78  would be formed at a complimentary angle to promote engagement therebetween.  
         [0055]    The lugs  54  are extended circumferentially around the male coupling  34 , leaving an opening sized to permit operation of the spring  65  and passage of the latching tabs  78 . The free end  65   b  of each spring  65  is shaped to interfere with the lugs  54 . Moreover, each lug  54  and spring  65  cooperatively defines a uniform path around which the latching tabs  78  may travel when the female coupling  36  is rotated.  
         [0056]    The gap or indexing notch  60  is defined by the elongated sloped portion  65   a  of each spring  65  and the guide surface  58  of each lug  54 . The gap or indexing notch  60  is configured to receive a point  82  of a respective latching tab  78  (see FIGS.  8 A- 8 C).  
         [0057]    The exterior side wall  50  has a portion  68  that defines a first surface of rotation around axis a that fits within the female coupling  36 . The first surface of rotation  68  is provided with a generally smooth finish for slidably engaging a sealing member  92  within the female coupling  36 . The first surface of rotation  68  is, in the illustrated embodiment, cylindrical, but could otherwise conform to conical, spherical, ellipsoidal or paraboloidal shapes, or other forms.  
         [0058]    In operation, as illustrated in FIGS.  8 A- 8 C, the female coupling  36  is coupled to the male coupling  34  by suspending the female coupling  36  vertically above the male coupling  34  with the latching tabs  78  resting on the lugs  54  of the male coupling  34 . The female coupling  36  is then rotated until the point  82  of each latching tab  78  drops into the gap or indexing notch  60  cooperatively formed by the spring  65  and the lug  54  (see FIG. 8A).  
         [0059]    An axial force is then applied to the female coupling  36  and attached filter cartridge  24  to push the female coupling  36  down onto the male coupling  34  against the spring  65  (see FIG. 8B). As a result of the interference between the point  82  of the latching tab  78 , the lug  54  and the spring  65  causes the spring  65  to rotate counterclockwise (as viewed from above) to permit passage of the enlargement portion  84  of the latching tab  78 . During this passage, guide surface  80  of the latch tab  78  slides by guide surface  58  of lug  54  (FIG. 4A).  
         [0060]    Once enlarged portion  84  of the latching tab  78  has cleared the latching surface  56  of the lug  54 , the spring  65  pushes against the female coupling  36  causing the top surface  81  of the latching tabs  78  to rotate clockwise (as viewed from above) into engagement with the latching surface  56  of each lug  54  (see FIG. 8C). Thereafter, the spring  65  provides a biasing force which deters inadvertent disengagement of the latching tab  78  from the lug  54 .  
         [0061]    To disengage the female coupling  36  from the male coupling  24 , a user simply rotates the female coupling  36  in a counterclockwise direction (as viewed from above) until the top surface  81  of the latching tab  78  clears the retaining or latching surface  56  of the lug  54 , and then lifts the female coupling  36  and attached filter cartridge  24 .  
         [0062]    Referring to FIGS. 5 and 6, the female coupling  36  also has an annular groove  90  opening on the interior side wall or second surface of rotation  72 . The second surface of rotation  72  matches the first surface of rotation  68  of the male coupling  34 . A sealing member  92  (FIGS.  8 A- 8 C), such as an O-ring, fits snugly in the groove  90  (see FIG. 3B and FIG. 6). When the coupling device  10  is assembled, the sealing member  92  engages the first surface of rotation  68  on the male coupling  34 , forming a tight seal that prevents unpurified material from bypassing the filter cartridge  24 .  
         [0063]    The number of latching tabs  78  (and lugs  54 ) dictate the maximum rotational displacement of the filter cartridge  24  until the point  82  of the latching tabs  78  finds a corresponding indexing notch  60 . In the embodiment depicted, two latching tabs  78  are provided. Thus, the maximum rotational displacement until the point  82  of the latching tabs  78  falls into engagement with the indexing notch  60  is approximately 180 degrees. Providing additional latching tabs (and a corresponding number of lugs  54 ) will reduce the rotational displacement by a proportional amount. For example, the use of four latching tabs will reduce the maximum rotational displacement to approximately 90 degrees (¼ turn).  
         [0064]    It will be appreciated that many alternative configurations fall within the scope of the present invention contemplated by the inventors. For instance, the filter cartridges  24  may hang down from an upper tube sheet  32 . Additionally, a filter-side coupling may be a polymeric adapter or male coupling instead of the female coupling while a steel coupling may be permanently attached to the filter conduit as the conduit-side coupling.  
         [0065]    The coupling device  10  has a polymeric female coupling  36  that can be incinerated or shredded along with other parts of the filter cartridge  24  for disposal after the female coupling  36  is used in hazardous or radioactive material processes. Incineration and shredding reduces volume of radioactive material which must be contained in secure containers at monitored storage facilities.  
         [0066]    Also, the male coupling  34  has lugs  54  designed to spread an axial separation force laterally, by providing a generally flat predetermined retaining surface  56  on each lug  54  for impacting the top surface  81  of the latching tab  78  so the full force is not directed to a single point on the female coupling  36 . The lugs  54 , latching tabs  78  and springs  65  are configured so that only an axial force is needed to fully engage the female coupling  36  on the male coupling  34 .  
         [0067]    While various embodiments of the present invention have been shown and described, it should be understood that other modifications, substitutions and alternatives can be made without departing from the spirit and scope of the invention, which should be determined from the appended claims.