Patent Publication Number: US-6708396-B2

Title: Universal crimping tool

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of patent application Ser. No. 09/356,859, filed 19 Jul. 1999, now U.S. Pat. No. 6,293,004, granted 25 Sep. 2001, for LENGTHWISE COMPLIANT CRIMPING TOOL by Randall A. Holliday. 
    
    
     This invention relates to crimping tools, and more particularly relates to a novel and improved hand-held crimping tool for crimping different types and lengths of connectors onto coaxial cables in a simplified and highly effective manner. In the hereinbefore referred to U.S. Pat. No. 6,293,004 for LENGTHWISE COMPLIANT CRIMPING TOOL, a hand-held crimping tool is automatically adjustable to compensate for slight differences in length of coaxial cable fittings, such as, differences resulting from manufacturing tolerances, dirt or wear. In that tool, the coaxial cable fitting is inserted into a seat on a die portion so that the cable end is in facing relation to a plunger. The plunger has a chuck and spring-loaded biasing member at one end in facing relation to the die portion, and a crimpable connector is loosely assembled on the cable end between the biasing member and seat so that when the plunger is advanced toward the seat it will force a preassembled crimping ring on the connector to radially compress the connector into sealed engagement with the cable end. Thus, the spring-loaded biasing member will absorb any continued movement of the chuck after the crimping ring contracts the connector to its maximum limit onto the cable end and automatically compensate for slight differences in effective length of the connector end. 
     Previously, in U.S. Pat. No. 5,435,167 for CABLE END COMPRESSOR, assigned to the assignee of this invention, a hand-held tool is disclosed for terminating different length and type cable end connectors and specifically adapted for terminating RG59 and RG6 coaxial cables. This tool is characterized by utilizing a hinged spacer which can be pivoted into position in front of an end stop on the tool to alter the effective length or distance between the spacer and plunger. For example, the spacer has a thickness equal to the difference in length between the RG59 connector and the RG6 connector, although a different type of compression member is employed than in the LENGTHWISE COMPLIANT CRIMPING TOOL. Accordingly, in a modified form of invention, it is proposed to incorporate a hinged spacer as hereinbefore described in combination with different extension tips in terminating different length coaxial cable connectors. 
     There is a continuing need for a crimping tool which is more versatile and capable of handling different sizes and lengths of connectors including but not limited to the RG59, RG6, RCA, BNA and IEC connectors. In addition, it is highly desirable to simplify the crimping operation by applying an axially directed force to a sleeve portion of the connector which receives the cable end in such a way as to impart radial compression to the connector into crimping engagement with the cable end. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide for a novel and improved universal crimping tool. 
     It is another object of the invention to provide for a novel and improved hand-held crimping tool for terminating a connector onto a coaxial cable in a simplified, highly efficient manner. 
     It is a further object of the present invention to provide for a novel and improved crimping tool which is conformable for crimping different sizes and types of connectors onto the end of a coaxial cable. 
     It is another object of the present invention to provide for a hand-held crimping tool of the type which is lengthwise compliant to compensate for slight differences in length of fittings owing to differences in tolerance and wear as well as to more substantial differences in length and size of different types of fittings. 
     It is still another object of the present invention to provide for a hand-held, universal crimping tool which automatically compensates for slight differences in length of the connector assembly and includes interchangeable adapters to compensate for more substantial differences in length and size of cable end connectors or fittings. 
     In accordance with the present invention, a tool has been devised for terminating different lengths of connectors onto a cable end wherein an elongated body has an end stop and plunger in aligned, axially spaced relation to one another and force-applying means are provided for axially advancing said plunger toward and away from the end stop whereby to radially compress a portion of the connector into crimping engagement with the cable end. The tool is comprised of a receiver including means resiliently mounting the receiver on the plunger, and adapter means between the plunger and end stop are operable to adjust the axial spacing between the receiver and end stop according to the length of connector being terminated onto the cable end. In a modified form, the body may include a hinged adapter at the end stop to alter the effective distance between the end stop and plunger according to the length of fitting to be terminated. As in the preferred form, a spring-loaded member on the plunger includes a receiver which is yieldable in an axial direction in response to advancement of the fitting into engagement with the end stop, and a lever arm is mounted on the body to axially advance the plunger toward and away from the end stop. Preferably, the receiver includes circumferentially spaced gripping portions either to releasably engage a collar at the end of the fitting or to engage one of a plurality of tip extenders for different length fittings. Each tip extender includes a slotted cylindrical projection to receive the conductor pin projecting beyond the deformable sleeve of the cable and an abutment for the end of the collar on the fitting. 
     There has been outlined the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. In this respect, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a preferred form of crimping tool in accordance with the present invention; 
     FIG. 2 is a longitudinal sectional view of the preferred form of crimping tool shown in the expanded position with an F-connector assembly in position to be crimped; 
     FIG. 3 is a sectional view of the tool and connector assembly illustrated in FIG. 3 at the completion of the crimping operation; 
     FIG. 4 is another sectional view of a preferred form of crimping tool with an RCA assembly in position to be crimped; 
     FIG. 5 is a sectional view of the tool and connector assembly illustrated in FIG. 5 at the completion of the crimping operation; 
     FIG. 6 is another longitudinal sectional view of the preferred form of tool shown in the open or expanded position for a BNC connector; 
     FIG. 7 is a sectional view of the tool illustrated in FIG. 6 at the end of the crimping operation; 
     FIG. 8 is an exploded view of a modified form of adapter for the tool of the present invention; 
     FIG. 9 is a fragmentary view in detail of the hinged portion of the adapter; 
     FIG. 10 is a side view in detail of the adapter shown in FIGS. 8 and 9; and 
     FIG. 11 is a perspective view of the modified form of adapter shown in FIGS. 8 to  10 . 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT 
     Referring in more detail to the drawings, FIGS. 1 to  7  illustrate a preferred form of tool  10  which is made up of an elongated body  12  having a yoke  14  at one end to define an end stop and is in facing relation to a raised portion  16  of the body having an axially extending, plunger-receiving bore  18  which communicates with a channel-shaped opening or recess  20 . The undersurface of the body  10  is scalloped as at  22  to define gripping portions for the fingers in manually grasping the tool. A lever arm  24  has a right angle pivotal end portion  26  which is mounted on a pivot shaft  28  adjacent to one end of the recessed portion  20  opposite to the end stop  14 . The pivotal end  26  is offset at substantially right angles to the length of the lever arm  24  and is provided with a groove  30  for insertion of one end of a floating link  32 . The link  32  is pivotally attached as at  31  within the grooved portion  30  and at its opposite end is pivotally attached as at  33  to a bifurcated end  34  of plunger  36 . The lever arm  24  tapers away from the pivotal end  26  and terminates in a relatively narrow free end portion  38 . 
     A cross pin or rivet  40  is inserted into the bifurcated end portion  34  and a transverse bore at the end of the plunger  36  so as to anchor the plunger to the bifurcated end  34 . 
     The plunger  36  has an outer sleeve  42 , the latter terminating in a flanged end  44  adjacent to the rivet pin  40  and at its opposite end bears against a series of spring elements  46  which are retained in a generally cup-shaped housing  48  on the end of the plunger. The spring elements  46  are illustrated as a series of stacked annular disks or washers canted in opposite directions and mounted under compression between the end wall of the housing  48  and end of the liner  42 . As shown, the disks are arranged in a “series stack”, but may be arranged in a “parallel stack” or nested relation to one another, or in a “parallel/series stack” depending on the amount of flexion desired for a given load. Other types of resilient members in the form of spring elements that may be employed are illustrated in my hereinbefore referred to U.S. Pat. No. 6,293,004, for LENGTHWISE COMPLIANT CRIMPING TOOL and incorporated by reference herein. The plunger assembly is slidable through a bushing  50  which surrounds the bore  18  in the raised portion  16  of the body  10 . 
     The end of the plunger  36  which carries the spring elements  46  and housing  48  is provided with a bore  52  for insertion of shaft  53  on a tip extender  60 , and a receiver  54  includes an annular base portion  55  which is sandwiched between the tip extender and housing  48 . A plurality of circumferentially spaced tabs  56  extend from the base  55  toward the end stop  14 , each of the tabs  56  being of generally concavo-convex configuration, and of a thin resilient metal or plastic material. In this way, the tabs  56  are capable of flexing at least to a limited extent about their connection to the base  55  in retaining the end of a connector A in a manner to be hereinafter described. 
     In order to accommodate different length standard end connectors, such as, the F-connector A in FIGS. 2 and 3, adapter means in the form of a tip extender  60  is releasably inserted into the receiver  54 . The extender  60  is in the form of a generally cylindrical body  63  having a bore  64  and an upwardly facing slot or channel  65  in a reduced end or nose portion  66  of the body  63  communicating with the bore  64 . In accordance with conventional practice, the F-connector A intended for retail use is shorter than the commercial F-connector. For this purpose, a substitute adapter  60 ′ which has a longer nose  65  than the extender  60  is inserted into a recess  67  and threadedly connected to a screw  68  which projects into the recess from the cavity  20 . In this manner, the extender  60 ′ is readily accessible and may be substituted for the extender  60  so as to compensate for the shorter length of F-connector. The end stop  14  includes an upwardly facing, generally U-shaped channel  72 , and a seat  73  having a beveled end surface and of bifurcated or generally U-shaped configuration mounted in facing relation to the extender  60  and receiver  54 . The coaxial cable C is then placed in the channel  72  of the end stop  14  during the crimping operation so as to be in alignment with the plunger  36 . 
     In use, the cable C is prepared according to connector requirements to provide the proper braid exposure at B and length of center conductor D. The connector A is loosely assembled onto the cable with the aid of a starter guide G which is mounted on the end of the center conductor D and extends forwardly through the central bore  64 . The tool  10  is illustrated in the open position in FIG. 1 with the connector A loosely assembled onto the cable C between the extender  60  and the seat  73 . The ferrule H on the end of the connector is guided over the slotted end of the extender  60  with the aid of the guide G and the cable C placed in the slot  62  of the end stop  14 . The body  10  is grasped in one hand with the fingers encircling the scalloped portions  22  and, with the other hand, the lever arm  24  is pressed toward the closed position against the body  10  thereby causing the plunger  36  to slide toward the end stop  14  as shown in FIG.  3 . Under continued advancement, the crimping ring R will become firmly positioned in the seat  73  and may slidably advance toward the extender  60  thereby causing the sleeve portion S 1  and S 2  of the connector assembly to be radially compressed into firm crimping engagement with the cable. 
     FIGS. 4 and 5 illustrate the application of the tool  10  for an RCA connector designated at A′ and which contains the same make-up of elements as described with reference to the connector A in FIGS. 2 and 3 but is shorter. As in FIGS. 2 and 3, the cable C is inserted into the connector A′ and placed in the end stop  14 . However, the cable C is aligned with the plunger without the aid of the starter guide G. The ferrule H is aligned axially with respect to the end of the cable C by advancing the ferrule over the nose  65  of the extender  60  and moving the end of the cable C against the end of the nose  65  with the inner conductor pin, not shown, projecting into the channel  66  of the extender  60 . Again, as the lever arm or handle  24  is closed against the body  12  of the tool  10 , the plunger  36  is advanced toward the yoke or end stop  14  to axially advance the crimping ring R over the sleeves S 1  and S 2  in radially crimping the connector F′ onto the cable C. 
     FIGS. 6 and 7 illustrate use of the tool  10  in crimping shorter connectors than the F series and RCA, such as, a BNA type of connector designated at N onto a cable C without the use of an extender  60 . Instead, the leading end of the connector N is inserted directly into the receiver  54  until it abuts the base  55 . As the handle  24  is closed down against the body, once again a crimping ring R on the connector N will be axially advanced and radially compress the sleeves S 1  and S 2  into crimping engagement with the cable C. 
     DETAILED DESCRIPTION OF MODIFIED FORMS OF INVENTION 
     FIGS. 8 to  11  illustrate a modified form of invention for use with shorter connectors in which a flip-up adapter  80  is hinged at  82  onto a modified form of end stop  84 . Like elements to those of FIGS. 1 to  7  are correspondingly enumerated. The end stop  84  is affixed at the end of the body  12  so as to form a continuation of the channel-shaped end stop  14 ′. A pair of return portions  86  extend from the lower end of the attachment  84  and are reverse-curved downwardly to receive hinge pins  82  at the lower edge of the adapter  80 . The adapter  80  is also generally channel-shaped and includes a beveled end surface  88  which forms a seat for the end of the crimping ring R in the process of terminating the connector onto the cable C. An oblong spring plate  90  is affixed to the lower end of the hinge which bears against the portions  86  and exerts increasing pressure on the portions  86  as the adapter  80 ′ is raised into a vertical position. For shorter connectors, the flip-up adapter  80  is pivoted upwardly into the position illustrated in FIG. 11 to receive the end of the crimping ring as described. However, when the tool is used with longer connectors, the flip-up adapter is hinged or pivoted downwardly against spring pressure to rest in the recessed area  92  in the body; or if desired the tip  60  can be removed. Accordingly, the adapter  80  may be used alone or in combination with one of the tips  60  thereby obviating the need for multiple crimping tools for terminating different length connectors. 
     It is therefore to be understood that the above and other modifications and changes may be made to the preferred and alternate forms of invention described herein without departing from the spirit and scope of the invention and reasonable equivalents thereof.