Abstract:
A canted coil spring includes a first section having a plurality of first canted coils generally canted at an acute first angle relative to a first direction of a centerline extending through the first canted coils, and at least a second section coupled to the first section and having a plurality of second canted coils generally canted at an acute second angle relative to a second direction of the centerline extending through the second canted coils. The second direction is opposite to the first direction when the centerline is in a linear configuration. A method of manufacturing the canted coil includes fabricating a first wire section in a canted helical configuration thereby forming the plurality of first coils, and fabricating at least a second wire section in a canted helical configuration thereby forming the plurality of second coils. The first wire section is coupled to the second wire section.

Description:
CROSS-REFERENCED TO RELATED APPLICATION 
       [0001]    The present application claims the benefit of the filing date of Provisional Application Ser. No. 61/244,403, filed Sep. 21, 2009, the contents of which are expressly incorporated herein by reference. 
     
    
     FIELD OF ART 
       [0002]    The present application generally relates to canted coil springs, and more particularly, to methods, apparatus, and systems related to longitudinal canted coil spring contacts to facilitate assembly. 
       BACKGROUND 
       [0003]    Canted coil springs can be used to, among other things, achieve consistent contact between components. Due to the deflective or slanted properties of canted coil springs, reliable contact with near constant contact force can be maintained with tolerance variations between contacting parts and surface unevenness. A canted coil spring may be wrapped around an object such as a piston or rectangular member, placed in housing grooves, or attached to components in order to facilitate mechanical or electrical contact with other parts. When the object is viewed along its cross section, a length of the spring on one side of the object has coils that are canted in an opposite direction as coils on the other side of the object. As a result, when the object is inserted into a receiving object along the length of the spring such that longitudinal spring contact occurs between the coils and the receiving object, the opposite cant in the coils can cause interference and/or resistance, which may result in the inability for insertion or a higher force on the coils along one side of the object compared to the opposing side. Accordingly, the insertion can be difficult, cumbersome, and/or cause misalignment due to the uneven forces exerted on the spring, which may cause a turn or a twist in the objects. An example a conventional canted coil spring that is wrapped around an object and used for a longitudinal spring contact with sliding insertion can be found in  FIGS. 8A and 8B  of Patent Application Publication No. US 2009/0160139, the contents of which are expressly incorporated herein by reference for all purposes. 
       SUMMARY 
       [0004]    A canted coil spring according to aspects of the disclosure includes a first section comprising a plurality of first canted coils generally canted at an acute first angle relative to a first direction of a centerline extending through the first canted coils, and at least a second section coupled to the first section and comprising a plurality of second canted coils generally canted at an acute second angle relative to a second direction of the centerline extending through the second canted coils, the second direction being opposite to the first direction when the centerline is in a linear configuration. 
         [0005]    According to one aspect of the disclosure, the canted coil spring comprises at least an additional section having a plurality of additional canted coils generally canted at an acute angle relative to the first direction or the second direction. 
         [0006]    According to one aspect of the disclosure, the first section is welded to the second section. 
         [0007]    According to one aspect of the disclosure, the first section and the second section are spaced apart along the centerline, and the canted coil spring comprises a section disposed between the first section and the second section without coils canted in the first angle or the second angle. 
         [0008]    According to one aspect of the disclosure, the first section and the second section are connected by at least one straight wire extending along the centerline. 
         [0009]    According to one aspect of the disclosure, the first section and the second section form a continuous one-piece section. 
         [0010]    A canted coil spring system according to aspects of the disclosure includes an object having a first side and a second side opposite to the first side and a canted coil spring. The canted coil spring comprises a first section a plurality of first canted coils generally canted at an acute first angle relative to a first direction of a centerline extending through the first canted coils, and at least a second section comprising a plurality of second canted coils comprising coils generally canted at an acute second angle relative to a second direction of the centerline extending through the second canted coils, the second direction being opposite to the first direction when the centerline is in a linear configuration. When the canted coil spring is mounted around the object such that at least a portion of the first section extends along the first side of the object and at least a portion of the second section extends along the second side of the object, the coils in the portion of the first section and the coils in the portion of the second section are canted in generally the same direction. 
         [0011]    According to one aspect of the disclosure, the object includes a groove configured to receive at least a portion of the canted coil spring. 
         [0012]    According to one aspect of the disclosure, the groove longitudinally extends around the object in a V-shaped configuration. 
         [0013]    According to one aspect of the disclosure, the groove longitudinally extends around the object in a slanted configuration. 
         [0014]    According to one aspect of the disclosure, the groove has one of a rectangular, a V-shaped, a tapered, or a dove-tailed cross-sectional shape. 
         [0015]    According to one aspect of the disclosure, a width of the groove is greater than or less than a width of the coils of the first section or the second section. 
         [0016]    According to one aspect of the disclosure, an end of the first section of the canted coil spring is connected to an end of the second section of the canted coil spring to mount the canted coil spring on the object. 
         [0017]    According to one aspect of the disclosure, when the canted coil spring is mounted on the object, the at least one additional section extends along a side of the object different from the first side and the second side. 
         [0018]    A method of manufacturing a canted coil spring according to aspects of the disclosure includes fabricating a first wire section in a canted helical configuration thereby forming a plurality of first coils canted at an acute first angle relative to a first direction of a centerline extending through the first coils, and fabricating at least a second wire section in a canted helical configuration thereby forming a plurality of second coils canted at an acute angle relative to a second direction of the centerline extending through the second coils, the second direction being opposite to the first direction when the centerline is in a linear configuration. The first wire section is coupled to the second wire section. 
         [0019]    According to one aspect of the disclosure, the method includes fabricating the first wire section and the second wire section from a single wire such that the first section and the second section are continuous one-piece portions of a single wire. 
         [0020]    According to one aspect of the disclosure, the method includes fabricating at least one additional wire section in a canted helical configuration thereby forming a plurality of additional coils canted at an acute angle relative to the first direction or the second direction of the centerline extending through the additional coils. 
         [0021]    According to one aspect of the disclosure, the method includes welding the first section to the second section. 
     
    
     
       DESCRIPTION OF DRAWINGS 
         [0022]    These and other features and advantages of the present assemblies and methods will become appreciated as the same become better understood with reference to the specification, claims and appended drawings briefly described below. 
           [0023]      FIG. 1  is a schematic diagram of a canted coil spring provided according to one exemplary embodiment. 
           [0024]      FIG. 2  is a schematic diagram of the canted coil spring of  FIG. 1  shown wrapped around an object. 
           [0025]      FIG. 3  is a cross-sectional view of  FIG. 2  taken along section  3 - 3  of  FIG. 2 . 
           [0026]      FIG. 4  is a partial perspective view of the spring of  FIG. 1  wrapped around an exemplary shank and being inserted into an exemplary housing. 
           [0027]      FIG. 5  is a cross sectional view of the shank of  FIG. 4  taken along section  5 - 5  of  FIG. 4  during insertion of the shank into the housing. 
           [0028]      FIG. 6  is a cross-sectional view of a spring according to embodiment of  FIG. 1  shown wrapped around a shank, where the ends of the spring are shown to be welded together. 
           [0029]      FIG. 7  is a schematic diagram of a canted coil spring provided according to one exemplary embodiment. 
           [0030]      FIG. 8  is a cross-sectional view of the spring of  FIG. 7  shown wrapped around a shank, where the ends of the spring are shown to be welded together. 
           [0031]      FIG. 9  is a side cross-sectional view of a canted coil spring provided according to an exemplary embodiment shown mounted around a shank, where the shank is being inserted into a housing. 
           [0032]      FIG. 10  is a cross-sectional view of the spring, shank and housing of  FIG. 9  taken at section  10 - 10  of  FIG. 9 . 
           [0033]      FIG. 11  is a side cross-sectional view of another canted coil spring provided according to an exemplary embodiment shown mounted around a shank, where the shank is being inserted into a housing. 
           [0034]      FIG. 12  is a cross-sectional view of the spring, shank and housing of  FIG. 11  taken at section  12 - 12  of  FIG. 11 . 
           [0035]      FIG. 13  is a side cross-sectional view of another canted coil spring provided according to an exemplary embodiment shown mounted around a shank, where the shank is being inserted into a housing. 
           [0036]      FIG. 14  is a cross-sectional view of the spring, shank and housing of  FIG. 13  taken at section A-A of  FIG. 13 . 
           [0037]      FIG. 15  is a cross-sectional view of the spring, shank and housing of  FIG. 13  taken at section B-B of  FIG. 13 . 
           [0038]      FIG. 16  is a schematic diagram of a canted coil spring provided according to an exemplary embodiment. 
           [0039]      FIG. 17  is a side cross-sectional view of a canted coil spring provided according to an exemplary embodiment shown mounted around a shank, where the shank is being inserted into a housing. 
           [0040]      FIG. 18   a  is a side cross-sectional view of a canted coil spring provided according to an exemplary embodiment shown mounted in a groove of a shank that is wider than the spring coils, where the shank is being inserted into a housing. 
           [0041]      FIG. 18   b  is a side cross-sectional view of a canted coil spring provided according to an exemplary embodiment shown mounted in a groove of a shank that is narrower than the spring coils, where the shank is being inserted into a housing. 
           [0042]      FIG. 19   a  is a side cross-sectional view of a canted coil spring provided according to an exemplary embodiment shown mounted in a V-shaped groove of a shank, where the shank is being inserted into a housing. 
           [0043]      FIG. 19   b  is a side cross-sectional view of a canted coil spring provided according to an exemplary embodiment shown mounted in a tapered-bottom groove of a shank, where the shank is being inserted into a housing. 
           [0044]      FIG. 20  is a side cross-sectional view of a canted coil spring provided according to an exemplary embodiment shown mounted in a groove that longitudinally extends on the shank in a V-shaped configuration. 
           [0045]      FIG. 21  is a cross-sectional view or  FIG. 21  taken along section C-C of  FIG. 20 , where a housing in which the shank is inserted is also shown. 
       
    
    
     DETAILED DESCRIPTION 
       [0046]    The detailed description set forth below in connection with the appended drawings is intended as a description of embodiments of a canted coil spring, a canted coil spring system, and methods for making the same and is not intended to represent the only forms in which the present assemblies and methods may be constructed or used. The description sets forth the features and the steps for using and constructing the canted coil springs, the canted coil spring systems, and methods in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions and structures may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the assemblies and methods. As denoted elsewhere herein, like element numbers are intended to indicate like or similar elements or features. 
         [0047]    A canted coil spring  30  according to one exemplary embodiment is shown in  FIG. 1 . The canted coil spring  30  includes a first section  32  having a plurality of coils  34  and a second section  36  having a plurality of coils  38 . A centerline C extends through the coils  34  of the first section  32  and coils  38  of the second section  36 . The coils  34  of the first section  32  are canted at a first acute angle α 1  relative to a direction CR of the centerline C. The coils  38  of the second section  36  are canted at a second acute angle α 2  relative to a direction CL of the centerline C that is opposite to the direction CR. Accordingly, the coils  34  of the first section  32  are canted toward the direction CR, while the coils  38  of the second section  36  are canted toward the direction CL. Thus, the coils  34  and  38  are canted in opposite directions. The angles α 1  and α 2  may be the same or different. In the embodiment of  FIG. 1 , the angles α 1  and α 2  are shown to be the same. The first section  32  and the second section  36  are connected at a transition area  40 . 
         [0048]    Referring to  FIGS. 2 and 3 , when the canted coil spring  30  is wrapped around an object  50 , which may be a shank and referred to herein as the shank  50 , the coils  34  and  38  are canted generally in the same direction because the directions CR and CL of the centerline C are no longer opposite to each other. Referring now to  FIGS. 4 and 5 , when the shank  50  is inserted in an entry direction ED into another object  52 , which may be a housing for receiving the shank  50  and may be referred to herein as the housing  52 , the spring  30  makes sliding contact along its length, which may be referred to herein as longitudinal sliding contact, with the inner walls  54  of the housing  52 . As shown in  FIG. 5 , the coils  34  of the first section  32  and the coils  38  of the second section  36  are canted opposite to the entry direction ED of the object  50 . Accordingly, since the angles α 1  and α 2  of the spring  30  are the same in this embodiment, a resistance created by the longitudinal sliding contact between the first section  32  and the corresponding inner wall  54  of the housing  52  is similar to and in the same direction as the resistance created by the longitudinal sliding contact between the second section  34  and the corresponding inner wall  54  of the housing  52 . Because the first section  32  and the second section  36  are opposite to each other relative to the entry direction ED or a removal direction RD, any misalignment and/or twisting in the shank  50  that may be caused during insertion into the housing  52  or removal of the shank  50  from the housing  52  is reduced. Furthermore, because both the coils  34  and  38  are canted away from the entry direction ED and are canted toward the removal direction RD, insertion of the shank  50  inside the housing  52  creates less resistance compared to withdrawal of the shank  50  from the housing  52 . Therefore, the effort or force required to insert the shank  50  into the housing  52  is less than the effort or force required to withdraw the shank  50  from the housing  52 , which may be a preferred feature for certain applications of the spring  30 . As understood from the foregoing, the reduced insertion force compared to withdrawal force is provided by canting the coils of the spring on both side of the shank along the same direction. 
         [0049]    Referring again to the exemplary embodiment of the spring  30  shown in  FIG. 1 , the transition area  40  includes a straight wire, which is a continuous one-piece part with the first section  32  and the second section  36 . Accordingly, the first section  32 , the transition area  40  and the second section  36  are fabricated in one piece from the same wire. The straight wire in the transition area  40  may be used in applications where absence of a spring force is preferred along a particular portion of the spring. Furthermore, as shown in  FIG. 2 , the straight wire allows the spring  30  to be wrapped around the shank  50  such that the straight wire is positioned at an end of the shank  50  where either no contact with the housing  52  occurs or a presence of a spring force is not preferred. However, one of ordinary skill in the art will readily recognize that the transition area  40  can be fabricated having any shape, dimensions, and material(s) so as to provide a particular function to the spring  30 . For example, the transition area  40  can be as minimal as possible such that an end coil  34  of the first section  32  directly connects with an end coil  38  of the second section  36 . The transition area  40  may be a canted coil spring having different characteristics than the first section  32  and/or the second section  36 . Furthermore, the transition area  40  may be a regular spring, another type of elastic structure such as an elastomeric part, or any other structure having any shape, dimensions and/or material(s) that can provide a preferred function. The transition area  40  can also be separately formed and subsequently attached to the two spring sections  32 ,  36 . 
         [0050]    Referring back to  FIG. 1  and to  FIG. 6 , in one exemplary embodiment, when the spring  30  is wrapped around the shank  50 , the ends  39 R and  39 L of the spring  30  can be connected in order to secure and/or maintain the spring  30  on the shank  50 . The ends  39 R and  39 L can be connected by devices and methods that are known to those of ordinary skill in the art. For example, the ends  39 R and  39 L of the spring  30  can be welded together, which is shown in  FIG. 6  with a weld bead  56 . The ends  39 R and  39 L can also be connected together with fasteners or similar devices (not shown) so as to allow the ends to be disconnected when necessary and connected back together. In other embodiments, the spring  30  is installed in the housing and not on the shank with at least two different sections of the spring located on two different sides of an axis canted in the same direction. 
         [0051]    Referring to  FIGS. 7 and 8 , a spring  60  according to another exemplary embodiment includes a first section  62  with coils  64  and at least a second section  66  with coils  68 . The first section  62  and the second section  66  are separate canted coil springs that are joined at the transition area  40  by welding as shown by a weld bead  70   a.  However, the first section  62  and the second section  66  can be connected by any method other than welding, such as by using fastening device or means for joining. Referring to  FIG. 8 , when the spring  70  is wrapped around the shank  50 , the ends  69 R and  69 L of the spring  70  can be connected in order to secure and/or maintain the spring  30  on the shank  50 . The ends  69 R and  69 L can be connected by devices and methods that are known to those of ordinary skill in the art. For example, the ends  69 R and  69 L of the spring  70  can be welded together, which is shown in  FIG. 8  with a weld bead  70   b.  The ends  69 R and  69 L can also be connected together with fasteners or similar devices (not shown) so as to allow the ends to be disconnected when necessary. 
         [0052]    In one exemplary embodiment shown in  FIGS. 9 and 10 , a spring  100  having a first section  102  with coils  104  and a second section  106  with coils  108  is received in grooves  111  of a shank  110 . Similar to the spring  30  of  FIG. 1 , the coils  104  and  108  are generally canted in the same direction when positioned around a shank  110  as shown. For connection with a housing  112 , the shank  110  can be inserted into the housing  112 , during which the spring and the coils  104  and  108  make longitudinal sliding contact with the housing  112 . The grooves  111  can align or assist in aligning the spring  100  with the entry direction ED and removal direction RD. Due to the presence of the grooves  111 , the first section  102  may only be connected to the second section  106  at the transition area  40 . Accordingly, the end  109 R of the first section  102  and the end  109 L of the second section  106  may not be connected. Furthermore, each groove  111  can be independent such as to have closed ends. Accordingly, the first section  102  and the second section  106  may not be connected at all and be separate since the sections  102  and  104  will be restricted from any movement within their respective grooves  111 . For example, the grooves can embody a dove-tail configuration for retaining the two spring sections within their respective grooves. Although the grooves  111  are shown and described herein to be in the shank  110 , the grooves  111  may alternatively be in the housing  112 . In another embodiment, both the shank  110  and the housing  112  may have grooves, where each groove receives at least a portion of the spring  100 . In  FIG. 10 , the grooves  111  are shown with generally straight or parallel sidewalls and with a canted or sloped bottom wall located between the sidewalls. However, the grooves  111  can have any cross-sectional shape in order to provide a preferred function for the spring  100 . For example, referring to  FIGS. 11 and 12 , the grooves  111  may have a dove-tail cross sectional shape (shown in  FIG. 12 ) in order to retain the spring therein after the spring  100  is mounted in the grooves  111 . In other embodiments, the groove is a flat bottom groove. 
         [0053]    In one exemplary embodiment shown in  FIGS. 13-15 , a spring  120  having a first section  122  with coils  124  and a second section  126  with coils  128  is wrapped around a shank  130  in a slanted configuration relative to the axis of the shank SX. The entry direction ED of the shank  130  is at an angle relative to the inner walls  134  of the housing  132 . In other words, the entry direction ED is oriented at a slant angle θ relative to the central axis HX of the housing  132 . Accordingly, by also orienting the grooves  131  at the same angle θ relative to the axis of the shank SX, the spring  120  and hence the coils  124  and  128  of the first section and second section  122  and  126 , respectively, are longitudinally aligned with the entry direction ED. 
         [0054]    In one exemplary embodiment shown in  FIG. 16 , a spring  140  includes four sections  142   a,    142   b,    146   a  and  146   b.  The spring  140  is wrapped around a shank  150  with a square cross section, which can be inserted into a housing (not shown) in two different entry and removal directions ED 1 , RD 1  and ED 2 , RD 2 . Accordingly, when the spring  140  is unwrapped from the shank  150  and linearly oriented, the coils  144   a  of section  142   a  and the coils  148   a  of section  146   a  are canted opposite to each other, and the coils  144   b  of section  142   b  and the coils  148   b  of section  146   b  are canted opposite to each other. Thus, when the spring  140  is wrapped around the shank  150 , the coils  144   a  and  148   a  are canted in the same direction, and the coils  144   b  and  148   b  are canted in the same direction. Although the shank  150  is shown in  FIG. 16  to have a rectangular or square cross-sectional shape, the shank can have any shape, such as oval, hexagonal, rounded rectangular or other geometrical shape. Accordingly, a spring according to the disclosure can be fabricated with any number of sections for use with such a shank. One of ordinary skill in the art will readily recognize from the above exemplary embodiments that the spring  140  can have any number of segments with the coils in each segment being angled opposite to or the same as adjacent or other segments in the spring in order to provide a preferred function for the spring or allow the use of the spring with an object having any shape or size. 
         [0055]    Referring to  FIGS. 17-19   b,  various exemplary grooves  179  in a shank  170  for receiving a canted coil spring  160  provided according to the exemplary embodiments are shown. In  FIG. 17 , the shank  170  is latched into a cavity of a housing  172  by a canted coil spring  160  provided according to one exemplary embodiment. The shank  170  has a flange  174  that is butted against the housing  172  upon insertion for controlling the depth of insertion into the housing. In  FIG. 18   a , the canted coil spring  170  is located in a square groove having a groove width that is wider than the major axis of the spring. The spring can be a radial spring. In  FIG. 18   b , the canted coil spring  160  is located in a tapered bottom groove. The groove has a groove width that is less than the major axis of the spring. The spring can be an axial canted coil spring or a radial canted coil spring. In  FIG. 19   a , the groove  179  has a V-shaped bottom, while in  FIG. 19   b , the groove has an inclined or a tapered bottom. Also shown in  FIGS. 19   a  and  19   b  are housing grooves. Thus, the spring grooves shown in  FIGS. 19   a  and  19   b  are formed from both the shank and the housing. These grooves in  FIGS. 19   a  and  19   b  are preferably used for latching or locking applications. 
         [0056]    Referring to  FIGS. 20 and 21 , a shaft  190  having a rectangular or square cross section is shown with a groove  189  that extends around the shaft  190  in a V-shaped configuration and is configured to receive a spring  180  according to one exemplary embodiment. The V-shaped configuration of the groove  189  reduces the angle of contact between the inner surface  194  of the housing  192  and the coils  184  and  188  of the spring  180  during insertion of the shank  190  in the housing  192 , and increases the angle of contact between the inner surface  194  and the coils  184  and  188  during removal of the object  190 . Accordingly, compared to an object having a radial groove and using the same spring as the spring  180 , the object of  FIGS. 20-21  requires a lower force for insertion in the housing  192  and a higher force for removal from the housing  192 . 
         [0057]    Exemplary methods of fabricating a canted coil spring will now be described with reference to  FIGS. 1 and 7 . A canted coil spring, such as the exemplary spring  30  of  FIG. 1  can be fabricated by methods that are known to those of ordinary skill in the art, except that the coils  34  of the first section  32  and the coils  38  of the second section  36  are fabricated to have coil angles that are canted in opposite directions. The transition area  40  can be fabricated to have any shape or length in order to provide a preferred function. In the exemplary embodiment of  FIG. 1 , the transition area  40  includes a straight wire. According to another exemplary embodiment shown in  FIG. 7 , the first section  62  and the second section  66  are fabricated separately and then connected together to form the spring  60  by, for example, welding or other methods. Based on the foregoing, one of ordinary skill in the art will readily recognize that a canted coil spring with a plurality of sections, as shown in the exemplary embodiment of  FIG. 16 , having coils with different cant angles can be fabricated as a one-piece continuous spring having the plurality of sections or as spring sections fabricated separately and then connected together. 
         [0058]    Although limited embodiments of canted coil springs, canted coil spring systems, and method of fabricating the canted coil springs have been specifically described and illustrated herein, many modifications and variations will be apparent to those skilled in the art. Accordingly, it is to be understood that the canted coil springs, the canted coil spring systems, and methods of fabricating these springs according to principles described herein may be embodied other than as specifically described herein. The canted coil springs, the canted coil spring systems, and methods of fabricating these springs are also defined in the following claims.