Abstract:
A method for manufacturing a purse ring is disclosed. In the method, a heat-treated steel frame interrupted by a gap is fabricated to partially circumscribe a passageway. At the edges of the gap, the frame includes a pivot mount and a push button biased to extend from an aperture are separated by a gap distance. Also, a heat-treated steel pivot arm is connected to the pivot mount. Structurally, the arm forms a key guide that terminates at a stop. In the method, a heat-treated steel sleeve forms a channel to slidably receive the arm. Also, the sleeve includes a key that slides within the guide to limit movement between the sleeve and the arm. Further, the sleeve includes a lateral opening that receives the push button to limit the maximum distance between the pivot member and the lateral opening to be substantially equal to the gap distance.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention pertains to seine equipment used in fishing operations. More specifically, the present invention pertains to purse rings which connect the fishing net to a pursing cable or purse line. The present invention is particularly, but not exclusively, useful for the manufacture of purse rings that are able to withstand great forces without deforming or exhibiting excessive wear. 
       BACKGROUND OF THE INVENTION 
       [0002]    In commercial fishing operations, the method of fishing known as purse seine fishing is an effective and widely used technique. The method is conceptually simple. A seine, or net, is fitted at one end with buoyant devices (e.g. floats) and is fitted at the other end with weighting devices (e.g. sinkers). As the seine is deployed in a rough circle, the weighted end of the seine submerges to cause the seine to hang essentially vertically in the water. To provide for seine retrieval, a purse line is attached to the weighted end of the seine by a plurality of connectors, known as purse rings. As the purse line is tightened by fishermen on the fishing vessel, the weighted end of the seine is drawn together to enclose fish within the seine. The weighted end, now pursed, is raised and drawn toward the fishing vessel. Simultaneously, support craft retrieve and draw in the buoyed end of the seine. In this way, fish are trapped in the seine as it is retrieved. 
         [0003]    During seine retrieval, the purse line, through its interaction with the purse rings, is used to both purse the seine and draw it toward the fishing vessel. As can be easily imagined, the forces which are generated between the purse line and the purse ring during these operations can be very substantial. Indeed, these forces can create significant strain on components within the purse ring and lead to deformation and, eventually, a complete failure of the purse rings and a fraying of the purse line which causes the purse line to snag on the netting. In either event, the operation is compromised and the purse rings may need to be replaced. 
         [0004]    Recent developments in the commercial fishing area have compounded the problem of purse ring wear because many of the now preferred fishing grounds are located in the Western Pacific Ocean. It happens, however, that purse seiner operations in the Western Pacific require deeper deployment of the seines than in other Pacific areas, because thermoclines in the Western Pacific often result in deeper schooling of food fish. Consequently, with the deployment of seines, the forces required to retrieve the seines (e.g. forces between the purse line and the purse rings) are greatly increased for longer periods of time. As a further consequence, standard purse rings, such as are used in other oceans of the world, are generally inadequate for use in the Western Pacific. 
         [0005]    In light of the foregoing, the present invention recognizes the need to significantly increase the durability of purse ring components against significant strain forces, to permit efficient seiner operations at greater depths in the ocean, and to prolong the useful life of purse rings used in seiner operations regardless of depth. It is therefore an object of the present invention to provide a method of manufacturing purse rings for use in purse seiner fishing operations which has a relatively long period of usefulness. It is a further object of the present invention to provide a method for manufacturing purse rings for seiner operations that reduce tolerances between moveable components in the purse ring. It is yet a further object of the present invention to provide a method for manufacturing purse rings for use in purse seiner operations that utilize heat-treated and hardened steel components. Another object of the present invention is to provide a method for manufacturing purse rings for purse seiner fishing operations which is relatively easy perform, which is comparatively cost-effective, and which results in purse rings having improved strength. 
       SUMMARY OF THE INVENTION 
       [0006]    In the present invention, a method for manufacturing a purse ring for use in deep-sea fishing operations is provided. In the method, a C-shaped, oblong steel frame is fabricated to circumscribe a passageway. Though oblong, the frame can be considered to have a proximal end and a distal end that are interconnected by a first side and a second side. As a C-shaped structure, the second side is interrupted by a gap that is defined by a first edge and a second edge. For purposes of the present invention, a pivot mount, such as a slot, is positioned at the first edge. Further, an aperture is formed at the second edge. Importantly, the pivot mount at the first edge and the aperture at the second edge are separated by a gap distance. 
         [0007]    In addition to the frame, a steel push button lock or locking pin is manufactured and biased to extend from the aperture at the second edge of the gap. Further, a steel pivot arm is formed and pivotably mounted to the pivot mount on the first edge of the gap. As a result, the pivot arm is able to close and open the passageway. Structurally, the pivot arm has a first end and a second end, and the first end includes a pivot member, such as a pivot pin, connected to the pivot mount. Further, the pivot arm defines a key guide that terminates at a key guide stop near the second end. 
         [0008]    In the method of the present invention, a steel sleeve is connected to the pivot arm via the key guide. Specifically, the sleeve forms a channel that defines an axis and slidably receives the pivot arm. In order to limit relative movement between the sleeve and pivot arm, a key or bolt is connected to the sleeve and passes through the key guide. Further, the sleeve forms a lateral opening. During use, the sleeve has a retracted position in which it rides over the first end of the pivot arm. Also, the sleeve has a fully extended position in which the lateral opening receives the push button lock and the key abuts the key guide stop, limiting the maximum distance between the pivot member at the first end of the pivot arm and the lateral opening to be substantially equal to the gap distance. 
         [0009]    During manufacturing of the purse ring, the components are engineered to have as little tolerance as possible. Specifically, the tolerance between the gap distance and the maximum distance is plus or minus about three-thousandths of an inch. Thereafter, each component is heat-treated and hardened to increase strength and durability. With these manufacturing standards, the shear strength of the push button lock, key and pivot member are sufficient to prevent deformation of the first side of the frame when external forces are applied to pull the first end and the second end of the frame away from one another. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which: 
           [0011]      FIG. 1  is a top view of a fishing vessel engaged in seiner operations; 
           [0012]      FIG. 2A  is a top view of the preferred embodiment of the purse ring engaged with a bridle line and purse line and showing the cable release arm in its closed configuration; 
           [0013]      FIG. 2B  is a top view of the purse ring of  FIG. 2A  with the cable release arm in its open configuration; 
           [0014]      FIG. 2C  is a side view of the purse ring of  FIG. 2B ; 
           [0015]      FIG. 3A  is a perspective view of the sleeve in the purse ring shown in  FIGS. 2A-2C ; 
           [0016]      FIG. 3B  is a cross sectional view of the sleeve of  FIG. 3A ; 
           [0017]      FIG. 4  is a cross sectional view showing the connection between a roller and the frame of the purse ring; 
           [0018]      FIG. 5  is a perspective view of an alternate embodiment of the purse ring of  FIG. 2A , shown with applied external forces and responsive internal forces; and 
           [0019]      FIG. 6  is a cross-section view of the push button locking pin as seen along the line  6 - 6  in  FIG. 2B . 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0020]      FIG. 1  shows a top overhead view of a purse seiner in operation using a plurality of purse rings designated  10 . As shown, the purse rings  10  interconnect a seine  12  and a purse line  14  during the fishing operations conducted by a seiner vessel  16 . For purposes of the present invention, it is to be appreciated that the purse line  14  will most likely be a cable. More specifically, purse rings  10  are attached to the seine  12  with bridle lines  18  which are, in turn, attached to the seine  12  by a chain  20 . Similar to the various embodiments for the purse line  14 , the bridle lines  18  may be cables, ropes or chains. Further, floats  22  are connected to the seine  12  to provide buoyancy to maintain one side of the seine  12  at or near the water&#39;s surface. At the same time, the chain  20  and purse rings  10  act as sinkers to vertically orient the seine  12 . As a result, the seine  12  is positioned to encircle schools of fish. When fish are encircled, they may be caught by pursing and retrieving the seine  12 . This requires the interaction of purse line  14  with the plurality of purse rings  10 . 
         [0021]    In  FIG. 2A , a more detailed perspective view of an individual purse ring  10  is provided. As shown in  FIGS. 2A ,  2 B and  2 C, purse ring  10  comprises a frame  24  which may generally be of any shape that is efficient for connecting purse line  14  to bridle line  18 . As depicted, the preferred ring  10  is substantially oblong in shape. Also, purse ring  10  is made of hardened steel and should be hard enough to resist frictional wear. Further, the elements of purse ring  10  should be chemically compatible with each other and with the materials of other components of seiner operations so as to minimize the effects of corrosion. 
         [0022]    Still referring to  FIG. 2A , it can be seen that frame  24  includes a proximal end  26  and a distal end  28 . Further, two sides  30  and  32  interconnect the ends  26 ,  28  to define an aperture  34 . As shown in  FIG. 2A , the ring  10  includes a proximal roller  36  that interconnects the sides  30 ,  32  and bridges the aperture  34 . Also, the ring  10  includes a distal roller  38  that further interconnects the sides  30 ,  32 . With this structure, it can be seen that the sides  30 ,  32  and the rollers  36 ,  38  define a periphery  40  around a passageway  42  that receives the purse line  14 . Further, the proximal end  26  and proximal roller  36  form an opening  44  for receiving the bridle line  18 . Typically, during pursing operations, the purse line  14  rides along the distal roller  38  and the sides  30 ,  32  adjacent the distal roller  38 . Therefore, the purse ring  10  is provided with hard facing  46  along both sides  30 ,  32  adjacent the distal roller  38 . Along the side  30 , this hard facing  46  effectively extends from the proximal roller  36  to the distal roller  38 . For purposes of the present invention, the hard facing  46  is comprised of at least one layer of a metal having improved strength and wear resistance such as Tube Alloy 240-O manufactured by McKay. Further, the hard facing  46  is preferably austempered to provide an even tougher and more wear resistant surface with less distortion. 
         [0023]    As shown in  FIG. 2A , the proximal roller  36  is cylindrical. Further, the distal roller  38  is substantially cylindrical, but includes a slight taper toward its center to form a guide which facilitates a more efficient rolling contact of the distal roller  38  with purse line  14 . Further, each roller  36 ,  38  is connected to frame  24  to provide for substantially free rotation and consequent reduced frictional wear during use. 
         [0024]    In  FIG. 2B , the illustrated embodiment of the purse ring  10  includes a side roller  39  mounted for rotation on the side  30 . Structurally, the side roller  39  has an axis of rotation that is substantially perpendicular to the axis of rotation for the rollers  36 ,  38 . 
         [0025]    Cross-referencing  FIG. 2A  with  FIGS. 2B and 2C , the ring  10  is shown to include a canted cable release arm  50  along the side  32  of the frame  24 . Structurally, the canted cable release arm  50  includes a pivot arm  52  which is formed with an end  54  and an end  56  (see  FIG. 2B ). As shown in  FIG. 2C , the frame  24  includes an extension  58  that is canted with respect to the frame  24 . Further, the pivot arm  52  is pivotably mounted to the extension  58  via a pivot mount or pin  59 . With this engagement, the pivot arm  52  is able to clear the side  30  of the frame  24  as it pivots from the closed configuration  50  shown in  FIG. 2A  to the open configuration  50 ″ shown in  FIGS. 2B and 2C . As shown, the pivot arm  52  is able to clear the side  30  of the frame  24  and pivot inwardly toward the proximal roller  36  until the pivot arm  52  is substantially parallel to the proximal roller  36 . It will be appreciated that when pivot arm  52  is pivoted to the open configuration  50 ″, it interrupts the periphery  40  to allow the purse line  14  to be moved into and out of the passageway  42 . 
         [0026]    Further, the cable release arm  50  is provided with a sleeve  60  that has a flared proximal end  62  and a distal end  64 . Referring to  FIGS. 3A and 3B , the structure of the sleeve  60  may be more easily understood. As illustrated, the sleeve  60  forms a channel  66  that extends along an axis  68  from the proximal end  62  to the distal end  64 . As seen in  FIGS. 2A-2C , the channel  66  slidably receives the pivot arm  52 . As shown in  FIG. 3A , at its distal end  64 , the sleeve  60  has an end face  70  with a surface  72  that is substantially perpendicular to the axis  68 . As shown, a notch  74  is formed in the sleeve  60  at the end face  70 . Referring to  FIG. 3B , it may be seen that the notch  74  includes a sloping surface  76  that forms an angle of about forty-five degrees with the end face surface  72 . 
         [0027]    As seen in  FIGS. 3A and 3B , the sleeve  60  also forms a lateral opening  78  to the channel  66 . Importantly, this lateral opening  78  is axially aligned with the notch  74  as detailed below. Also, as perhaps best seen in  FIG. 3A , the lateral opening  78  is flared with an oblong recess to facilitate operational access to the locking pin  86  (See  FIG. 3A ). Further, the sleeve  60  includes apertures  80  for receiving a key or bolt  82  to engage the sleeve  60  with the pivot arm  52  as shown in  FIGS. 2A-2C . Specifically, the pivot arm  52  forms a key guide  83  that slidingly receives the bolt  82 . Axial movement of the bolt  82  in the key guide  83  is limited by a stop  85 . In  FIG. 3B , it can be seen that the flared proximal end  62  of the sleeve  60  has an inner diameter D 1  while the rest of the sleeve  60  has an inner diameter D 2 , with D 1 &gt;D 2 . 
         [0028]    Referring back to  FIG. 2A , the sleeve  60  is shown in an extended position  60 ′ in which the distal end  64  engages the frame  24 . Specifically, the frame  24  includes an abutment member  84  (shown in  FIG. 2B ) that is received within the channel  66  when the cable release arm  50  is in the closed configuration ( FIG. 2A ) and the sleeve  60  is in the extended position  60 ′. As a result, the sleeve  60  prevents pivotable movement of the cable release arm  50  when extended about the abutment member  84 . Further, the ring  10  provides for the ability to lock the sleeve  60  in the extended position  60 ′. 
         [0029]    As shown in  FIG. 2B , the ring  10  provides a locking pin or push button lock  86  on the abutment member  84 . Specifically, the locking pin  86  is positioned in an aperture  88  formed in the abutment member  84  and is biased outward from the aperture  88 . After the cable release arm  50  is closed, the sleeve  60  may be extended to engage the abutment member  84 . During the extension of the sleeve  60 , the sloping surface  76  of the notch  74  contacts and automatically depresses the locking pin  86 . When the sleeve  60  is fully extended, the locking pin  86  reaches and extends through the lateral opening  78  in the sleeve  60 . As a result, the locking pin  86  holds the sleeve  60  in the extended position  60 ′. 
         [0030]    When the sleeve  60  is disengaged from the locking pin  86  and moved to its retracted position  60 ″, the flared proximal end  62  of the sleeve  60  rides over the end  54  of the pivot arm  52 . As a result, the sleeve  60  does not interfere with the pivoting capability of the pivot arm  52 . This allows the pivot arm  52  to be pivoted to be substantially parallel to the proximal roller  36  and facilitates the removal of the purse line  14  from the passageway  42 . 
         [0031]    Referring now to  FIG. 4 , the connection of a roller  36  (or  38 ) to the frame  24  is illustrated. As shown, the frame  24  may be considered to have an outer face  90  and an inner face  92 . For connection with the roller  36 , a threaded bore  94  extends from the outer face  90  of a side  30  and through the inner face  92  of the side  30 . Further, the threaded bore  94  passes through the inner face  92  of the other side  32  and stops within that side  32 . Structurally, the roller  36  includes a threaded shaft  96  that is received within the bore  94  and remains fixed in place during use. Also, the roller  36  includes a bushing  98  that rotates about the fixed shaft  96 . As shown, the ring  10  further includes a plug  100  that engages the threads to seal and prevent contamination at the shaft  96 . Also, the frame  24  forms a drain aperture  102  that extends from the threaded bore  94  to the outer face  90  of the side  32 . In an alternate embodiment, the shaft  96  and bushing  98  can be replaced with a roller pin of a type known in the pertinent art. 
         [0032]    In the method for manufacturing a purse ring  10 , each purse ring component is fabricated from steel, hardened and heat-treated. As a result, the purse ring components have increased strength and resistance to strain. Further, the components are engineered to have little tolerance, e.g. approximately three-thousandths of an inch, in order to withstand external forces. As shown in  FIG. 2B , the frame  24  is fabricated with a gap distance D G  between the pivot mount  59  and the aperture  88 . Referring to  FIG. 2A , it can be seen that the pivot arm  52  is in its fully extended position, with a maximum distance D M  between the pivot mount  59  and the lateral opening  78 . For purposes of the present invention, D M  has a value between D G  and D G ±0.003 inch. In the fully extended position, the lateral opening  78  receives and engages the locking pin  86 . Further, the bolt  82  abuts and is limited from further movement by the stop  85 . Also, the pivot mount  59  provides connection between the pivot arm  52  and the side  32 . 
         [0033]    Referring to  FIG. 5 , the effect of the small tolerance of the purse ring components may be understood. In this case an alternate embodiment for the purse ring  10 ′ is shown with expanded shoulders  103   a  and  103   b  to provide a larger opening  105  in the purse ring  10 ′ for receiving the purse line  14  (See  FIG. 2A ). Also, the proximal end  26  is bowed for the purse ring  10 ′ to provide a larger opening  44  for receiving the bridle line  18 . As shown, regardless which embodiment of purse ring  10  is used, when external forces F 1  and F 2  are applied to the purse ring  10  or  10 ′ in the normal course of use, reaction forces F 30  and F 32  are created in the sides  30 ,  32  of the purse ring  10 . When the pivot arm  52  does not interconnect the side  32 , then F 32  is zero, and F 30  must counteract F 1  and F 2 . Further, when the side  32  is interconnected, but the interconnection between the side  32 , the pivot arm  52  and the sleeve  60  is loose, F 30  must still counteract F 1  and F 2 . Therefore, a tight fit with little tolerance between the side  32  and the pivot arm  52  at the pivot mount  59 , between the pivot arm  59  and the sleeve  60  at the bolt  82  and stop  85 , and between the sleeve  60  and the side  32  at the lateral opening  78  and locking pin  86  allows the side  32  to add strength to the purse ring  10  under the forces F 1  and F 2 . As a result, F 30 +F 32  may counteract F 1  and F 2 . Therefore, side  30  undergoes far less strain and the service life of the purse ring  10  is increased when side  32  is constructed with little tolerance. Further, the total reactive force F 30 +F 32  is increased, allowing the purse ring  10  to withstand the application of greater external forces F 1  and F 2 . 
         [0034]    Referring now to  FIG. 6  it will be seen that the push button assembly for locking pin  86  includes a cylinder  104  that is affixed to the abutment member  84  by means such as welding  106 . In detail, the cylinder  104  is formed with a shoulder  108  that defines the aperture  88  and the locking pin  86  is formed with a base  110  that abuts the shoulder  108  when the locking pin  86  extends through the aperture  88 . There is also a set screw  112  that engages with the cylinder  104  to hold a spring  114  within the cylinder  104  between the set screw  112  and the base  110  of locking pin  86 . Thus, with the above assembly, the locking pin  86  can be selectively depressed, against the reactive force of the spring  114 , to move the sleeve  60  over the abutment member  84  and then released to engage the locking pin  86  with the sleeve  60 . Importantly, in this combination, both the cylinder  104  and the locking pin  86  are made of stainless steel. Thus, there is a stainless steel-in-stainless steel combination that effectively resists the corrosion that would otherwise occur. 
         [0035]    While the particular Improved Force Resistant Purse Ring as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims.