Abstract:
A coaxial connector of the type wherein an inner connector member of a female connector is adapted for secure engagement with a connector member of a male connector. The coaxial connector is positioned around the connector member of the male connector and the connector member of the female connector when the coaxial connector is in its locked position. A spring basket with an angular frontal surface is positioned around the connection member of the male connector. A sleeve with an angular internal surface for engaging the angular frontal surface of the spring basket is reciprically positioned around the spring basket and the connection member of the male connector. The sleeve has at least one locking groove that extends substantially parallel to the major axis along a portion of the body thereof. A spring nut is provided with a hollow front end disposed within the sleeve and at least one upstanding locking finger disposed within the at least one locking grove of the sleeve. A spring is partially disposed within the hollow front end of the spring nut, and the spring is positioned between the spring nut and the connection member of the male connector respectively such that when the spring nut is pushed in a forward axial direction relative to the sleeve to lock the coaxial connector, the spring is compressed and the internal angular surface of the sleeve engages the angular frontal surface of the spring basket forcing the spring basket to apply a radially inward force on the connection member of the female connector, holding the female connector in place. The spring provides an axial force on the connection member of the male connector and forces the connection member of the male connector into engagement with the connection member of the female connector.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to coaxial cable connectors and, more particularly, but not by way of limitation, to coupling mechanisms for coaxial cable connectors. 
     2. History of Related Art 
     A coaxial cable is generally characterized by having an inner conductor, an outer conductor, and an insulator between the inner and outer conductors. The inner conductor may be hollow or solid. At the end of coaxial cable, a connector is attached forming a coaxial cable assembly and facilitating mechanical and electrical coupling of the coaxial cable to electronic equipment and other cables. The method of and apparatus for the mechanical and electrical coupling of the connector to the coaxial cable has for a number of years been the subject of considerable design innovation. For example, to effectuate electrical contact between the inner contact of the connector and the inner conductor of the cable, the inner contact may be soldered or otherwise secured in some other fashion to the inner conductor. To effectuate electrical contact between the body member of the connector and the outer conductor of the cable, a myriad of design issues arise. One design issue relates to the configuration of the outer conductor of the cable. A connector for a coaxial cable having a helically corrugated outer conductor and a hollow, plain cylindrical inner conductor is, for example, described in U.S. Pat. No. 3,199,061 (Johnson et al.). The Johnson patent describes a self-tapping connector. Such connectors are time-consuming to install and relatively expensive to manufacture. Also, when the inner connector is made of brass, over-tightening causes the threads to strip off the connector rather than the end portion of the inner conductor of the cable, and thus the connector must be replaced. 
     More recent coaxial connector designs have addressed methods of and apparatus for quickly and easily attaching a connector to a coaxial cable with improved efficiency. U.S. Pat. No. 5,802,710, assigned to the assignee of the present invention, and incorporated herein by reference, teaches a method of attaching a connector to a coaxial cab e that allows the depth of the inner c contact relative to the body member of the connector to be easily controlled. In this manner, the depth of the inner contact relative to the body member of the connector is consistent from one assembly to the next. The method set forth therein also provides a moisture barrier between the cable and the connector without the use of rubber O-rings, thereby protecting the connector from detrimental environmental conditions. 
     Another very important design aspect of coaxial connectors has been, and currently is, the coupling mechanism that facilitates an interlocking engagement between mating male and female coupling sections. For example, U.S. Pat. No. 4,941,846 (Guimond, et al.) describes a quick connect/disconnect connector for coaxial cables which can be used with unmodified standard coaxial couplings having externally facing threads. The connector includes a connector housing having a plurality of movable fingers which have inwardly facing ridge portions that mesh with the externally facing threads of the coaxial coupling. When the connector coaxial line segment is pushed onto the coupling, the fingers move in such a way as to allow the ridge portions to interlock with the screw threads. The connector can be used for microwave and can also be used as a SMA or TNC connector. Disconnecting is accomplished by pulling the sleeve backward which releases the fingers from their interlocking position. 
     Another connector design addressing the coupling mechanism is set forth and shown in U.S. Pat. No. 4,138,181 (Hacker, et al.). The Hacker patent describes a releasable electrical connector having a receptacle component and a plug component which can be mated by relative rotation between the components and separated by a straight breakaway force. Pins on the receptacle components are engaged in a spring biased sleeve in the plug component. Moreover, a spring is provided around the male connector and biases the connector body toward the receptacle to provide better contact between the connectors. 
     Likewise, U.S. Pat. No. 4,545,633 (McGeary) generally describes a male plug and a female receptacle that are connected together by means of fingers on the male plug which are spread and are held by the female receptacle. The connector is unplugged by sliding a sleeve rearwardly against an internal spring and moving the locking tabs to a unlocked position. 
     Similarly, U.S. Pat. No. 6,267,612B1 (Arcykiewicz, et al.) teaches an adaptive coupling mechanism incorporating a multi-lined locking ring to engage the threads of a conventional rotational coupling system member. 
     These and related designs exemplify the innovation in the effort for improved high performance coaxial cable connector couplings that are easy and fast t install and uninstall one to the other under field conditions and which may also be economically manufactured. However, these push-pull type connectors are typically insecure and, by definition, release when a sufficient axial force is applied. 
     The most common male to female coaxial connector used in the prior art is that of a threaded coupling assembly on the male end which screws on to a standard size female end. While this connector provides good physical stability, it is quite time consuming to connect or disconnect such coaxial connectors. The need for further improved male coaxial connector for coupling mating connector members of a coaxial connector with an enhanced axial interface force still remains. 
     It has been well established that connectors incorporating push-pull coupling assemblies permit faster installation than the threaded coupling assemblies. Typical push-pull couplings also often provide more reliable locking mechanisms because vibrations will have a less tendency to cause disconnection as compared to threaded connectors which are more prone to the deleterious effect of vibration. There are obviously no “cross-threading” problems with push-pull connectors, because such problems are by definition the problem of threaded engagement. Also, push-pull connectors are quicker to connect or disconnect. However, threaded coupling assemblies, when installed correctly, are more physically secure (they do not disconnect when something pulls on them) whereas push-pull connectors, by definition, disconnect when a sufficient axial force is applied. 
     It would be a distinct advantage to provide a connector that quickly connects with a standard threaded female coaxial end, without having to screw the connector on to the female end, that provides efficient and reliable coupling of the male and female connector members under field conditions. Also, it would also be advantageous if the connector did not disengage upon the application of a pure axial force. Enhanced coupling aspects, such as increased axial compression between male and female connector members, provide improved reliability. The present invention provides such a reliable coaxial connector coupling with a reciprocally mounted sleeve positioned around a connector member adapted for enhanced axial interface forces between said male and female connector members. The push-pull connector described herein includes at least one spring for urging the female connector into engagement with the male connector while providing both locked and unlocked positions therebetween. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete understanding of the method and apparatus of the present invention may be obtained by reference to the following Detailed Description when taken in conjunction with the accompanying Drawings wherein: 
     FIG. 1 is a side elevational view of one embodiment of a male coaxial connector constructed in accordance with the principles of the present invention, the male coaxial connector positioned in the process of mating with a female connector; 
     FIG. 2 is a side elevational, cross-sectional view of the male coaxial connector of FIG. 1 taken along lines  2 — 2  thereof and illustrating the post mated, unlock d position of said male coaxial connector thereof; 
     FIG. 3 is a side elevational, cross-sectional view of the male cc axial connector of FIG. 1 further illustrating the mated, locked position of said male coaxial connector thereof; 
     FIG. 4 is a side elevational, cross-sectional view of the male coaxial connector and female connector of FIG. 1 separated one from another further illustrating the pre-mated unlocked position of said male coaxial connector illustrating the operation thereof; 
     FIG. 5 is an exploded perspective view of the male coaxial connector of FIG. 1, constructed in accordance with the principles of the present invention; 
     FIG. 6 is an enlarged, perspective view of the inner conductor of the male coaxial connector illustrated in FIG. 5; 
     FIG. 7 is an enlarged, perspective view of the spring nut of the male coaxial connector of FIG. 5; 
     FIG. 8 is an enlarged, perspective view of the spring basket of he male coaxial connector of FIG. 5; 
     FIG. 9A is an enlarged, perspective view of the sleeve of the male coaxial connector of FIG. 5; 
     FIG. 9B is a side elevational, cross-sectional view of the sleeve of FIG. 9A; 
     FIG. 10 is an enlarged, perspective view of the male insulator of the male coaxial connector of FIG. 5, 
     FIG. 11A is an enlarged, perspective view of the connection member of the male connector of FIG. 5; 
     FIG. 11B is a side elevational, cross-sectional view of the connection member of the male connector of the male coaxial connector of FIG. 5; and 
     FIG. 12 is a side elevational view of a tool specifically adapted for facilitating the engagement and actuation of the male coaxial connector of FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     It has been discovered that a reciprocally mounted coupling assembly formed with means for enhancing the axial interface force between male and female connector members of a coaxial connector can provide a myriad of advantages and improved reliability. The coupling assembly of the coaxial connector of the present invention is constructed for axially biasing the mating coupling members of the coaxial connector of the present invention into each other. The inter-engagement of the axially biased coaxial coupling members of the present invention provides a tighter, more reliable connection with the quick installation convenience available in a push-pull connector. The coupling assembly of the coaxial connector of the present invention also provides radial forces to ensure sufficient engagement between the male and female connection members. 
     Referring first to FIG. 1 there is shown a side elevational view of one embodiment of the male coaxial connector  10  constructed in accordance with the principles of the present invention coupled with a female connector  100 . In order to accommodate the female connector  100 , a hollow sleeve  12  is provided that fits around the female connector  100  when the male coaxial connector  10  is engaged. In order to receive a connection member of a female connector  26 , the sleeve  12  has an open front end. In order to receive a spring nut  14 , he sleeve  12  has an open rear end. To facilitate the locking action of the male coaxial connector  10 , the spring nut  14  has a locking finger  16  extending radially outward therefrom which fits wit in a locking groove  18  formed in the sleeve  12  such that when the spring nut  14  and the sleeve  12  are pushed together and rotated with respect to each other, the locking finger  16  is held in place at the end of the locking groove  18 . This groove/finger assembly ensures that the male coaxial connector  10 , when locked, cannot come unlocked when a pure axial force is applied to the assembly. It should be noted that more than one locking finger/locking groove combination may be provided. For the male coaxial connector  10  to work for its intended purpose it must be mounted at the end of a coaxial cable (as must the female connector  100 ). Such methods of connection are well known in the art. The preferred method for connection of the male coaxial connector  10  to a coaxial cable is disclosed in U.S. Pat. No. 5,802,710 which is incorporated by reference herein for such teachings. 
     Referring now to FIG. 2, there is shown a side elevational, cross-sectional view of the male coaxial connector  10  of FIG. 1 in a mated, unlocked position. In order to provide outer electrical communication between the male coaxial connector  10  and the female connector  100 , the connection member of the female connector  26  abuts the connection member of the male connector  28  and both connection members are constructed of electrically conductive material. These connection members serve as the outer conductors of the coaxial connection between the male and female connectors. To provide inner electrical communication between the male coaxial connector  10  and the female connector  100 , an inner conductor  34  o the male coaxial connector  10  is provided within the connection member of the male connector  28  and is received in the inner conductor region  38  within the female connector  100 . In order to insulate the inner conductors from the outer conductors, the male coaxial connector  10  and the female connector  100  are provided with male and female insulators  32 ,  36  respectively, that electrically isolate the outer conductors from the inner conductors. It is well known in the industry to utilize rubber, plastic or the like as insulating material within coaxial connectors, and likewise the use of brass, copper and similar electrically-conducting material for the construction of the conducting portions of the male coaxial connector  10 , as well as the female connector  100 . 
     Still referring to FIG. 2, in order to hold the connection member of the female connector  26  in place when it is inserted into the male coaxial connector  10 , a spring basket  22  is adapted for receiving the connection member of the female connector  26 . In order to translate axial force into radial force, the spring basket  22  has an angular front surface  24  which is adapted for engaging the internal angular surface  20  of the sleeve  12  when the sleeve  12  is moved in a rearward direction with respect to the spring basket  22 . This relationship will be discussed in further detail below. In order to bias the male coaxial connector  10  to its unlocked position, a spring  30  is positioned around the connection member of the male connector  28  and within the hollow front end of the spring nut  14  applying equal and opposite axial forces on these two components when the spring  30  is compressed. The spring  30  also urges the connection member of the male connector  28  into electrical engagement with the connection member of the female connector  26  when the male coaxial connector  10  is in its mated, locked position. This relationship will be discussed in further detail below. 
     Referring now to FIG. 3, the male coaxial connector  10  is shown in its mated, locked position. To lock the male coaxial connector  10 , the sleeve  12  is moved in a rearward axial direction with respect to the spring nut  14  while the connection member of the female connector  26  is mated against the connection member of the male connector  28 . As the sleeve  12  moves in the rearward axial direction with respect to the spring nut  14 , the locking finger  16  of the spring nut  14  travels down the locking groove  18  of the sleeve (see FIG. 1) such that the sleeve  12  must be forced against and rotated with respect to the spring nut  14  with sufficient force for the male coaxial connector  10  to be held in its locked position by the locking finger  16 /locking groove  18  relationship (FIG.  1 ). 
     Still referring to FIG. 3, in order to securely hold the female connector  100  in place when the male coaxial connector  10  is locked, the internal angular surface  20  of the sleeve  12  engages the angular front surface  24  of the spring basket  22  as the sleeve is moved in a rearward axial direction to lock the male coaxial connector  10 . The angular nature of the engagement of the internal angular surface  20  of the sleeve  12  and the angular front surface  24  of the spring basket  22  translates a portion of the axial force required to lock the male coaxial connector  10  into an inward radial force applied from the spring basket  22  on the connection member of the female connector  26 . The radial force applied from the spring basket  22  is of sufficient magnitude to securely hold the female connector  100  in place. 
     In order to provide good electrical contact between the male coaxial connector  10  and the female connector  100 , the male coaxial connector  10  of the present invention urges the connection member of the male connector  28  and the connection member of the female connector  26  together in both axial and radial directions. To ensure the radial engagement between the connectors, the spring basket  22  applies an inward radial force against the connection member of the female connector  26 , which in turn applies an inward radial force on the connection member of the male connector  28  securing electrical communication between the two. Application of this radial force is accomplished when the sleeve  12  is moved in a rearward axial direction with respect to the spring nut  14  and the internal angular surface  20  of the sleeve  12  is forced into engagement with the angular front surface  24  of the spring basket  22 . To ensure the axial engagement between the connectors, the spring  30  applies an frontal axial force on the connection member of the male connector  28  which urges it into axial engagement with the connection member of the female connector  26  securing electrical communication between the two. Because the inner conductor  34  and the male insulator  32  are fixed with respect to the connection member of the male connector  28 , the spring  30  also urges the inner conductor  28  into engagement with the female inner conductor  38 . Thus, when the male coaxial connector  10  of the present invention is locked, it provides both radial and axial forces on the female connector  100  to provide good electrical communication between the two. 
     Referring now to FIG. 4, the male coaxial connector  10  of the present invention is shown in its unmated, unlocked position. To allow the female connector  100  to fit within the male coaxial connector  10 , the front end of the sleeve  12  has an open diameter large enough to accommodate the connection member of the female connector  26 . Additionally, the spring basket  22  is biased to an open position such that the connection member of the female connector  26  can fit within before the male coaxial connector  10  and female connector  100  are locked together. The functional relationship between the female connector  100  and the spring basket  22  will be discussed in further detail below. 
     Referring now to FIG. 5, there is shown an exploded view of the male coaxial connector  10  of the present invention. The inner conductor  34  is of a size such that, when assembled, it fits securely within a hole through the male insulator  32 . Likewise, the male insulator  32  is of a size that, when assembled, it fits securely within the connection member of the male connector  28 . In order to facilitate the internal electrical connection between the male coaxial connector  10  and the female connector  100 , the front end of the inner conductor  34  protrudes from the connection member of the male connector  28  a distance sufficient to come into electrical contact with the female inner conductor  38  (FIG. 2) when the connectors are mated. To bias the male coaxial connector  10  to its open position and to urge the connection member of the male connector  28  toward the female connector when mated, the spring  30  is assembled around the connection member of the male connector  28  such that it abuts a radially extending ridge  42  on the connection member of the male connector  28 ; the other end of the spring  30  abuts a ridge (not shown) in the interior of the spring nut  14 . In order to hold the spring basket  22  in place with respect to the connection member of the male connector  28 , an inward-facing lip  46  on the spring basket  22  fits over and around a outward-facing lip  44  on the front of the connection member of the male connector  28 . The sleeve  12  fits over the spring basket  22  and connection member of the male connector  28  assembly and over the front end of the spring nut  14  such that the locking finger  16  fits into the locking groove  18  of the sleeve  12 . 
     Referring now to FIG. 6 there is shown a side elevational view of the inner conductor  34 . In order to provide electrical communication between a standard coaxial cable (not shown) and the female inner conductor  38  (not shown) the inner conductor  34  must be made of an electrically conductive material. As stated above, to ensure a secure fit between the inner conductor  34  and the male insulator  32 , the diameter of the front portion of the inner conductor  34  is approximately the same as the diameter of the hole formed through the male insulator  32 . When the inner conductor  38 , male insulator  32 , and connection member of the male connector  28  are assembled, the front portion of the inner conductor  34  protrudes in an axial direction outwardly from the connection member of the male connector  28 . This protrusion allow the inner conductor  34  to be received within the female inner conductor  38  when the male coaxial connector  10  is engaged with a female connector  100 . 
     Referring now to FIG. 7 there is shown a perspective view of the spring nut  14  of FIG.  1 . In order to facilitate engagement of the spring nut  14  with the sleeve  12 , the spring nut has at least one locking finger  16  extending radially outward from the exterior of the locking nut  14  that engages the locking grooves  18  of the sleeve  12  (not shown). To accommodate the connection member of the male connector  28  and the spring  30 , the internal diameter of the frontal portion of the spring nut  14  must be at least as large as that of the spring  30 . In order to allow a coaxial cable to pass through, the internal diameter of the rear portion of the spring nut  14  must be at least as large as the outer diameter of the coaxial cable (not shown). To allow a user to easily lock the male coaxial connector  10 , the external rear portion of the spring nut  14  is angled into planes whereas the remainder of the spring nut  14  is generally rounded. This allows a user to easily grip the spring nut  14  with a tool, such as a pair of pliers, to make locking the male coaxial connector  10  easier than if the user was attempting to lock the male coaxial connector  10  by hand. The preferred tool for this operation will be discussed in detail below. 
     Referring now to FIG. 8, there is shown a perspective view of the spring basket  22 . In order to allow front end of the spring basket  22  to compress evenly upon the connection member of the female connector  26  (not shown) when it is inserted therein, the frontal portion of the spring basket  22  is divided into equally spaced tines  52 . Each tine  52  has an angular front surface  24  that engages the internal angular surface  20  of the sleeve  12  and translates axial force from the sleeve  12  into radial compressive forces onto the connector member of the female connector  26  (not shown). In order to provide better gripping forces on a threaded connector member of a female connector  26  (not shown), the internal faces of the tines  52  are threaded to engage the threads on the connector member of the female connector  26  (not shown). Also, in order to hold the spring basket  22  in place with respect to the connection member of the male connector  28  (not shown), an inward-facing lip  46  on the spring basket  22  fits over and around a outward-facing lip  44  on the front of the connection member of the male connector  28 . 
     Referring now to FIGS. 9A and 9B there is shown a perspective view of the sleeve  12  and a cross-sectional view of the sleeve, respectively. In order to facilitate locking of the male coaxial connector  10 , at least one locking groove  18  is cut into the sleeve  18 . The locking groove is adapted to receive the locking finger  16  of the spring nut  14  such that when the spring nut  14  and the sleeve  12  are pushed together in an axial direction with sufficient force and rotated with respect to each other, the male coaxial connector  10  is in its locked position and will not come unlocked with the application of a purely axial force. In order to provide compressive force on the female connector  100  (not shown), the interior of the front end of the sleeve  12  has an internal angular surface  20  adapted to engage the angular front surfaces  24  of the tines  52  of the spring basket  22  (see FIG.  8 ). Thus, when the sleeve  12  is pushed in a rearward axial direction with an axial force with respect to the spring basket  22 , the internal angular surface  20  engages the angular front surfaces  24  of the tines  52  of the spring basket  22  and translates some of the axial force into radial compression forces on the tines  52  of the spring basket  22 , which in turn compress the connector member of the female connector  26  (see FIG.  8 ). 
     Referring now to FIG. 10, the male insulator  32  is shown. To accommodate the inner conductor  34 , a hole of approximately the same diameter as the frontal portion of the inner conductor  34  is formed therethrough. This ensures that the inner conductor  34  fits tightly within the male insulator  32  when the male coaxial connector  10  is assembled. To ensure that the male insulator  32  fits tightly within the connection member of the male connector  28 , the outer diameter of the frontal portion of the male insulator  32  is approximately the same as the inner diameter of the frontal portion of the connection member of the male connector  28 . 
     Referring now to FIGS. 11A and 11B, there is shown a perspective view and a cross-sectional view of the connection member of the male connector  28 , respectively. In order to allow the spring  30  (not shown) to apply an axial force on the connection member of the male connector  28 , a radially extending ridge  42  extends outwardly therefrom. Also, as described above, in order to hold the spring basket  22  in place with respect to the connection member of the male connector  28 , an inward-facing lip  46  on the spring basket  22  fits over and around a outward-facing lip  44  on the front of the connection member of the male connector  28 . To ensure that the male insulator  32  (not shown) fits tightly within the connection member of the male connector  28 , the inner diameter of the frontal portion of the connection member of the male connector  28  is approximately the same as the outer diameter of the frontal portion of the male insulator  32  (see FIG.  2 ). 
     Referring now to FIG. 12, there is shown a elevational view of a tool  68  for locking the male coaxial connector  10  of the present invention. To allow the tool  68  to fit over the rear end of the spring nut  14  (FIG. 7) and over a coaxial cable that the male coaxial connector  10  is attached to, the tool  68  has a cut-away hexagonal head  70  that fits over the angled planes of the rear of the spring nut  14 . Other types of cut-away heads may be used (such as square, octagonal, etc.) as long as the tool  68  fits whatever shape the rear portion of the spring nut  14  is formed into. To allow a user to easily lock the male coaxial connector  10  of the present invention, the user places the cut-away hexagonal head  70  of the tool  68  over the rear portion of the spring nut  14 . With his or her other free hand, the user grips the sleeve  12  and pushes the sleeve  12  and the spring nut  14  together by applying opposite axial forces on the hand holding the sleeve and the hand holding the tool  68 . As the locking finger  16  of the spring nut  14  travels up the locking groove  18  of the sleeve  12 , the user rotates the sleeve  12  (or the spring nut  14 ) with respect to the spring nut  14  (or the sleeve  12 ) locking the male coaxial connector  10  in place. 
     It is thus believed that the operation and construction of the present invention will be apparent from the foregoing description. While the method and apparatus shown or described has been characterized as being preferred it will be obvious that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the following claims.