Patent Publication Number: US-2011068247-A1

Title: Barbed anchor

Description:
BACKGROUND 
     This disclosure relates to the management of wires, cables and optical fibers, which are often found in large numbers in industrial machines and electronics assemblies to distribute electrical signals and/or light pulses. The routing of these wires, cables or fibers may be critical to prevent harmful contact or damage, and therefore, these items are routinely guided through the machines or electronics using routing accessories or “anchors” which are secured at predetermined locations. 
     Anchors for wire management functions are generally well-known. One common type of anchor has an adhesive applied to the bottom surface of a molded plastic mount, and the adhesive bottom of the mount is hand-pressed onto a panel in a selected location. Examples of these attachments are cable tie mounts and wire management saddles such as the type FTH and MWSB sold by Richco and the type ABM sold by Panduit. One disadvantage of the adhesive-backed mounts is that final placement of the mount is often inaccurate and inconsistent as the process of locating the mount is done by hand. Other disadvantages of the adhesive-backed mounts include (i) the adhesive tends to dislodge over time due to creep from sustained loads; (ii) the adhesive can be heat sensitive; (iii) the adhesive has limited shelf-life; (iv) the adhesive bond is sensitive to sheet metal surface cleanliness; and (v) the routing direction of the wires is permanently fixed since the anchor cannot be moved or rotated. 
     Other common types of mounts include integrally formed molded plastic barbed posts that are pressed through the sheet metal, or anchors that are attached using screws or rivets, such as the type WS-SE-A sold by Richco, and the type TM sold by Panduit. In each case, there is an undesirable protrusion on the opposite side of the sheet metal. This protrusion can be visually unpleasing, or it may interfere with other components of the machine. 
     Another type of self-clinching mount is disclosed in U.S. Pat. No. 6,981,683. However, this mount requires a special, uncommon rectangular punch to create a square hole in the sheet metal. Further, the routing is permanently fixed in such a mount. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a top perspective view illustrating a first embodiment of a self-clinching anchor having a barbed post. 
         FIG. 1B  is a top perspective view illustrating a second embodiment of a self-clinching anchor having a barbed post. 
         FIGS. 2A-2C  illustrate a sequence for installing the anchors of  FIG. 1A  or  1 B. 
         FIG. 3  is a top perspective view illustrating a third embodiment of an anchor having a barbed post. 
         FIGS. 4A-4C  illustrate a sequence for installing the anchor of  FIG. 3 . 
         FIG. 5A  is a top perspective view illustrating a fourth embodiment of an anchor having a barbed post. 
         FIG. 5B  is a bottom perspective view of the anchor shown in  FIG. 5A . 
         FIGS. 6A-6C  illustrate a sequence for installing the anchor of  FIG. 5A . 
         FIGS. 7A-7C  illustrate an alternative sequence for installing the anchor of  FIG. 5A . 
         FIGS. 8A-8E  are top perspective views of exemplary mounting accessories that may be used with the disclosed anchors. 
     
    
    
     DETAILED DESCRIPTION 
     Several embodiments of an anchor device are described. The anchor is used to secure a mounting accessory, such as a wire management device, to a sheet such as a metal panel or electronic circuit board. The body of the anchor includes a head portion and a post portion extending from the head portion, with barbs protruding from a portion of the post. A suitable mounting accessory includes a hole or recess sized in correspondence with the post, such that the barbs engage the walls of the hole or recess and thereby secure the mounting accessory onto the post. 
     In one preferred embodiment, the body of the anchor includes a head portion and a ring portion formed proximate to the head portion, which is useful for self-clinching to the underside of a panel. In another embodiment, the ring portion includes teeth for broaching engagement with the panel. Another embodiment includes an annular ring instead of the head and ring portions, useful for inserting from the top side of a panel, and then swaging or flaring the annular ring with a tool from the underside of the panel. Although some dimensions are provided, they are intended to be illustrative only. 
     Referring now to  FIG. 1A , a first embodiment of a self-clinching barbed anchor  10  is illustrated. The anchor  10  is preferably formed from solid lathe-turned carbon steel, stainless steel, brass or aluminum to be a solid body, and includes a post portion  12 , a head portion  14 , barbs  16  disposed on the post portion, and a ring portion  18  also disposed on the post portion. The barbs  16  are shown as three discrete ribs formed around the circumference of the post portion  12  at a location on the post distal from the head portion such that when the anchor  10  is mounted in a panel, the barbs are exposed above the panel for use in coupling with a mounting accessory. However, the barbs could take any number of physical forms to present one or more protrusions extending from the post portion  12  in order to exert pressure against the walls of a corresponding recess formed in the mounting accessory, for example. The ring portion  18  is shown as a single raised surface formed around the circumference of the post portion  12  nearer the head portion  14 , but in this embodiment, the ring portion is spaced apart from the head  14  by a groove  15 . In another embodiment that is not self-clinching, the ring portion  18  may be adjacent to the head portion  14 . Preferably, the post  12  includes a chamfered portion  12   a  at the top or free end of post. 
     Because there are a number of different types and sizes of mounting accessories, such as wire management devices, including cable tie mounts and wire saddles, the anchor  10  can be provided in a variety of configurations and sizes, and several different embodiments are described herein. In general, however, the diameter of the post  12  will be smaller than the opening in the sheet such that the post fits easily through the opening. In this embodiment, the ribs  16  and ring portion  18  have approximately the same diameter, which is larger than the diameter of the post  12  but still slightly smaller than the diameter of the opening. The head  14  has a larger diameter than the opening by approximately 15 to 20 percent. Typical panel openings range in size from approximately 0.150 inches to 0.240 inches. 
       FIG. 1B  shows an alternative embodiment for a self-clinching barbed anchor boa, which is nearly identical to the anchor  10  shown in  FIG. 1A , except that the post  12   b  is a dog point, i.e., a taller post. Thus, the mounting accessories are provided with a deeper recess to accommodate the dog point  12   b , for example, as shown in  FIGS. 8A and 8C . 
     In use, the metal sheet or panel  20  is turned upside down so that the underside  19  of the panel is facing up and the top side  21  is facing down, as depicted in  FIG. 2A . An anvil  2  is securely positioned adjacent the panel  20  underneath a hole  22  formed in the panel by punching or drilling, for example. The post portion  12  of anchor  10  is inserted by hand into the hole  22 , and the head portion  14  of the anchor  10  is then pressed downward with a punch  4  toward the anvil  2  in a known manner. This causes the head portion  14  to displace the sheet metal material around the hole  22 , forcing the displaced metal into the groove  15  between the head and the ring portion  18 . The applied pressing force should be consistent with typical values for minimum installation loads with conventional self-clinching hardware, depending upon the size of the part, the installation procedure, the sheet material and the sheet hole size. The head  14  is pressed until it becomes flush with the surface of the panel  20 , and the fully mounted anchor  10  is shown after reversing the sheet again in  FIG. 2B . At this point, the barbs  16  are exposed above the top surface  21  of the metal sheet such that a suitable mounting accessory can be pressed onto the anchor  10 . The mounting accessory may be any type of wire management device or other device that has a corresponding recess or opening adapted to receive the barbed post. 
     Lastly, the mounting accessory  30  is pressed onto the post  12 , as shown in  FIG. 2C . The mounting accessory  30  includes a recess  32  that corresponds to the post  12  and is slightly smaller than the barbs  16 , such that when the device  30  is pressed onto the anchor  10 , the barbs  16  engage the inside walls  31  of recess  32  to hold the device in place on the anchor. Alternatively, other mounting devices may simply have a hole or opening instead of a recess, although the same principles apply. See, for example,  FIGS. 8B ,  8 D and  8 E. 
     Referring now to  FIG. 3 , a third embodiment is illustrated as a barbed anchor  110  that is suitable for broaching into softer metals or plastics, such as printed circuit boards. The construction of anchor  110  is similar to that of anchor  10 , with post section  112  including chamfered edges  112   a , head portion  114  and barbs  116 . The difference is that ring portion  118  includes teeth  117  extending radially from the ring. The toothed ring  118  is slightly larger than the diameter of the hole, for example, by approximately 0.010 to 0.015 inches. Also, the ring portion  118  is shown as immediately adjacent to the head  114  on the proximal portion of the post  112 , rather than spaced apart from the head as with ring portion  18  and head  14  in  FIG. 1A . However, in another embodiment, the toothed ring could be spaced apart from the head (not shown). Further, the ring portion  118  is taller in dimension w than the ring portion  18 , measuring approximately 0.060 inches. 
     In use, the metal sheet or panel  120  is once again turned upside down so that the underside  119  of the panel is facing up and the top side  121  is facing down, as shown in  FIG. 4A . The anvil  2  is securely positioned adjacent the panel  120  underneath the hole  122 . The anchor  10  is inserted into the hole  122  such that the barbs  116  are exposed above the top side  121  and the toothed ring portion  116  is immediately adjacent the hole on the bottom side  119 . The head portion  114  is pressed downward with the punch  4  toward the anvil  2 , as depicted in  FIG. 4A . This causes the teeth  117  of the ring portion  118  to engage and deform the material in walls  124  of the circuit board  120 , and the fully installed anchor  110  is shown in  FIG. 4B . Finally, a mounting accessory  30  having a recess  32  (or an opening) sized in mating correspondence with the post  112  is pressed onto the anchor  110 , and the barbs  116 , which are slightly larger than the recess, engage the wall surfaces  31  of the device  30  inside the recess  32 , as shown in  FIG. 4C . Note that this embodiment does not necessarily result in the head  114  being flush with the bottom surface  119  of the circuit board  120 . 
     A fourth embodiment is illustrated in  FIGS. 5A-5B . Like the prior embodiments, anchor  210  is formed to include a post portion  212  and barbs  216 , but instead of a larger head portion and a ring portion, this embodiment has smaller head portion that is formed as an annular ring  213  defining an opening  213   a . The annular ring  213  is really part of the post  212 , but with a reduced diameter and a hollowed-out interior that allows the annulus to be flared or swaged in place. The diameter of the annular ring  213  is preferably approximately 80 percent of the diameter of the post  212 . 
     The fourth embodiment may secured to a panel by flaring or swaging the annulus. The flaring process is illustrated in  FIGS. 6A-6C , and the swaging process is illustrated in  FIGS. 7A-7C . 
     As shown in  FIG. 6A , the anchor  210  is hand-placed (upside down) into the annular opening  203  of anvil  202 . Next, the panel  220  is placed between the anvil  202  and press  204  such that the panel hole  223  is placed over the annular ring  213  of the anchor  210 . Note that panel hole  223  has chamfered edges  224  formed by drilling or stamping, depending on the type of material. Force is then applied by punch  204  such that the annular ring  213  is flared (bent outwardly) to clinch against the chamfered walls  224  of the opening  223 , and the fully mounted anchor  210  is shown (turned rightside up) in  FIG. 6B . Finally, a mounting accessory  30  having a recess  32  (or an opening) for mating correspondence with post  212  is pushed onto the post such that barbs  216  clinch against the walls  31  of the recess  32 , securing the mounting accessory in place, as shown in  FIG. 6C . 
     Referring now to  FIG. 7A , as before, the anchor  210  is hand-placed (upside down) into the annular opening  303  of anvil  302 . Next, the panel  320  is placed between the anvil  302  and press  304  such that the panel hole  323  is placed over the annular ring  213  of the anchor  210 . Force is applied by the punch  304  such that the annular ring  213  is swaged to clinch against the underside  319  of the panel  320  adjacent to the opening  323 , and the fully mounted anchor  310  shown (turned rightside up) in  FIG. 7B . Lastly, the mounting accessory  30  with recess  32  (or an opening) is pushed onto the post  212  such that barbs  216  clinch against the walls  31  of the recess, thereby securing the mounting accessory in place, as shown in  FIG. 7C . 
     Referring now to  FIGS. 8A-8E , various types of mounting accessories are illustrated as secured onto a barbed post, as described above. 
       FIG. 8A  shows a stand-off  130  having a snap-top  131  for receiving and supporting another sheet (not shown). The other sheet has a number of holes distributed across the sheet, and a corresponding number of stand-offs  130  mounted on the first panel have their snap-tops  131  pushed through the holes to hold the sheet in place. A recess  132  (shown in dashed lines) is formed in the stand-off  130  for receiving the anchor  10  to secure the stand-off to the first panel. The barbs  16  engage against the walls of the recess  132 . 
       FIG. 8B  shows a cable clamp  230  having a p-shape, that is, it is bent back over itself to create a throughway  231  for holding wiring. Further, rather than a recess, the clamp  230  has an opening  232  that is defined by an annular portion  233 . The clamp is pushed onto post  12  such that the barbs (not shows) clinch against the walls of the annular portion  233 . 
       FIG. 8C  shows a wire guide  330  having a throughway  331  mounted on top of a post  333  for routing wiring. A recess  332  (shown in dashed lines) is formed in the bottom of post  333  in order to mate with the barbed post  12 . 
       FIG. 8D  shows a wire saddle  430  having a pair of arms  434  that define a throughway  431  for routing wires. The base  435  of the wire saddle  430  includes an opening  432  that provides mating correspondence with the barbed post  12  such that the barbs (not shown) clinch against the walls of the base  435  in opening  432 . 
       FIG. 8E  shows a cable tie mount  530  having a pair of arms  534  each with opening  536 . The base  535  of the cable tie mount  530  includes an opening  532  that provides mating correspondence with barbed post  12  such that the barbs (not shown) clinch against the walls of the base  535  in opening  532 . The arms  534  are used as anchors for cable ties, which are threaded through the arms and looped around wiring that is routed between the arms. 
     In general, those skilled in the art to which this disclosure relates will recognize that many changes in construction and materials as well as widely differing embodiments will suggest themselves without departing from the spirit and essential characteristics of this disclosure. Accordingly, the disclosures and descriptions herein are intended to be illustrative, and not limiting, of the scope of the invention, which is set forth in the claims.