Patent Publication Number: US-9893463-B1

Title: Connector of process fieldbus decentralized peripherals

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the priority benefit of CN application serial No. 201621325299.9, filed on Dec. 5, 2016. The entirety of the above-mentioned patent applications is hereby incorporated by reference herein and made a part of specification. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a connector, and particularly to a connector of a process field bus decentralized peripherals (PROFIBUS-DP). 
     2. Description of the Related Art 
     A process Fieldbus (PROFIBUS) is a common technique in Fieldbus. The PROFIBUS comprises a technique of process field bus decentralized peripherals (PROFIBUS-DP) and a technique of process field bus process automation (PROFIBUS-PA). 
     Performance of the PROFIBUS-DP and the PROFIBUS-PA are better than performance of other kinds of PROFIBUS. The PROFIBUS is adapted to automation systems and communication between fieldbus signal units. The PROFIBUS may connect to a connector of a transmitter, an actuator, a transmission device, a fieldbus meter, or a fieldbus equipment, to sample and monitor fieldbus signals. 
     The PROFIBUS may replace common transmission cables by a pair of twisted pair wires. Therefore, construction cost of cables may be decreased, and time and cost of adjustment during construction may also be decreased. Further, maintenance time and cost may be decreased when a PROFIBUS system is operating. 
     With reference to  FIG. 16 , a topology of the PROFIBUS comprises a PROFIBUS master  161 , multiple PROFIBUS slaves  162 , and a PROFIBUS repeater  163 . The PROFIBUS master  161  connects to the PROFIBUS slaves  162  through connectors and cables of the PROFIBUS. The PROFIBUS master  161  may connect to the PROFIBUS repeater  163  through the connectors and cables, and may further connect to other PROFIBUS slaves  162  through the PROFIBUS repeater  163 . Then, a network of the PROFIBUS may be further expanded. 
     The PROFIBUS master  161  may cyclically read messages from the PROFIBUS slaves  162  through the topology of the PROFIBUS, and may transmit messages to the PROFIBUS slaves  162  through the topology of the PROFIBUS. 
     With reference to  FIG. 17 , the connector  170  of the PROFIBUS comprises a circuit board  171 , a connecting port  172 , and a plastic shell  173 . The circuit board  171  and the connecting port  172  are mounted in the plastic shell  173 . The plastic shell  173  is consisted of two half shells. Since one terminal of one of the two half shells is pivotally connected with one terminal of another of the two half shells, the plastic shell  173  is a flip shell. When the plastic shell  173  is covered, the circuit board  171  and the connecting port  172  are mounted inside the plastic shell  173 , and the connecting port  172  extends through the plastic shell  173  to connect to the PROFIBUS master  161 , the PROFIBUS slaves  162 , or the PROFIBUS repeater  163 . Two connectors  170  are connected together through the cable  174 , and two terminals of the cable  174  are respectively inserted into ends of the two connectors  170 . 
     However, as the circuit board  171  and the connecting port  172  are just mounted in the plastic shell  173 , the circuit board  171  and the connecting port  172  may not be tightly covered by the plastic shell  173 . The circuit board  171  and the connecting port  172  may be loosened, and the loosened circuit board  171  and the connecting port  172  may be disconnected from the cable  174 . Therefore, quality of the connector  170  may not be good. 
     Besides, since the plastic shell  173  may not shield the circuit board  171  from electromagnetic interference, a metallic shield  175  is mounted between the circuit board  171  and the plastic shell  173  to cover the circuit board  171 , and the metallic shield  175  may be further electrically connected with a shielding net layer of the cable  174 . Therefore, the metallic shield  175  may shield the circuit board  171  from electromagnetic interference. 
     However, since the metallic shield  175  may not totally cover the circuit board  171 , the connector  170  may not completely protect the circuit board  171  from the electromagnetic interference. Therefore, the connector  170  needs to be improved. 
     SUMMARY OF THE INVENTION 
     An objective of the present invention is to provide a connector of a process field bus decentralized peripherals (PROFIBUS-DP). The connector may protect a circuit board inside the connector from electromagnetic interference. 
     To achieve the foregoing objective, the connector comprises a circuit board, two communicating cables, an inner shell, a shielding layer, and an outer shell. 
     At least one connecting port is adapted to be mounted on the circuit board. 
     The two communicating cables each comprise two core wires and a shielding net layer. The two core wires are coated by the shielding net layer, such that the shielding net layer covers the two core wires. Ends of the two core wires are electrically connected to the circuit board. 
     The inner shell is mounted on the ends of the core wires by injection molding to cover the ends of the core wires of the two communicating cables. 
     The shielding layer covers the inner shell and the circuit board, and is electrically connected to the shielding net layers of the two communicating cables. 
     The outer shell is mounted on the shielding layer by injection molding to cover the shielding layer, and the at least one connecting port extends through the inner shell, the shielding layer, and the outer shell. 
     Since the inner shell and the outer shell are formed by injection molding, the circuit board may be tightly fixed in the connector. Therefore, quality of the connector may be improved. Further, since the shielding layer is mounted between the inner shell and the outer shell and the shielding layer is electrically connected to the shielding net layers of the two communicating cables, the circuit board may be completely protected from electromagnetic interference. 
     Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a first embodiment of a connector of a PROFIBUS-DP of the present invention; 
         FIG. 2  is a cross sectional view of the first embodiment of the connector of the PROFIBUS-DP of  FIG. 1 ; 
         FIGS. 3-7  are schematic views showing manufacturing flows of the first embodiment of the connector of the PROFIBUS-DP of  FIG. 1 ; 
         FIG. 8  is a perspective view of a second embodiment of a connector of a PROFIBUS-DP; 
         FIG. 9  is a cross sectional view of the second embodiment of the connector of the PROFIBUS-DP of  FIG. 8 ; 
         FIGS. 10-14  are schematic views to manufacture the second embodiment of the connector of the PROFIBUS-DP of  FIG. 8 ; 
         FIG. 15  is a schematic view showing the connectors of the PROFIBUS-DP of  FIGS. 1 and 8 ; 
         FIG. 16  is a schematic view of a conventional topology of a PROFIBUS; 
         FIG. 17  is a perspective view of a conventional connector of a PROFIBUS. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With reference to  FIGS. 1 and 2 , the present invention is a connector  10  of a PROFIBUS-DP. The connector  10  of the PROFIBUS-DP comprises a circuit board  11 , two communicating cables  12 , an inner shell  13 , a shielding layer  14 , and an outer shell  15 . 
     With reference to  FIG. 4 , at least one connecting port  111  is adapted to be mounted on the circuit board  11 . In a first embodiment, one connecting port  111  is mounted on the circuit board  11 . Each one of the two communicating cables  12  comprises two core wires  121  and a shielding net layer  122 . The two core wires  121  are coated by the shielding net layer  122 , such that the shielding net layer  122  covers the two core wires  121 . End of the two core wires  121  is electrically connected to the circuit board  11 . 
     The inner shell  13  is mounted on the ends of the core wires  121  by injection molding to cover the ends of the core wires  121  of the two communicating cables  12 . The shielding layer  14  totally covers the inner shell  13  and the circuit board  11 , and is electrically connected to the shielding net layers  122  of the two communicating cables  12 . 
     The outer shell  15  is mounted on the shielding layer  14  by injection molding to cover the shielding layer  14 . The connecting port  111  extends through the inner shell  13 , the shielding layer  14 , and the outer shell  15 . 
     Since the inner shell  13  and the outer shell  15  are manufactured by injection molding, the circuit board  11  may be tightly fixed in the connector  10  of the PROFIBUS-DP. Therefore, quality of the connector  10  may be improved. Further, since the shielding layer  14  is mounted between the inner shell  13  and the outer shell  15  and is electrically connected to the shielding net layers  122  of the two communicating cables  12 , the circuit board  11  may be completely protected from electromagnetic interference. Therefore, capability of shielding electromagnetic interference of the connector  10  of the PROFIBUS-DP may be increased. 
     With reference to  FIGS. 3 to 7 , a manufacture method of the first embodiment of the connector  10  of the PROFIBUS-DP is shown. As disclosed in  FIG. 3 , the circuit board  11  is provided. A connecting port  111 , a switch  112 , multiple conductive bars  113 , and any other necessary elements (not shown in the figures) are mounted on the circuit board  11 . The connecting port  111  is mounted on an end of the circuit board  11 . 
     As disclosed in  FIG. 4 , the ends of the two core wires  121  of the two communicating cables  12  may be welded on the conductive bars  113  of the circuit board  11 . 
     As disclosed in  FIG. 5 , the inner shell  13  is mounted on the circuit board  11  by injection molding to cover the circuit board  11  and the ends of the two core wires  121  of the two communicating cables  12 . Further, the inner shell  13  may cover the switch  112 , the conductive bars  113 , and any other necessary elements mounted on the circuit board  11 . In the first embodiment, the connecting port  111  further comprises two first through holes  1111 , and the inner shell  13  further comprises two second through holes  131 . The two second through holes  131  of the inner shell  13  respectively communicate with the two first through holes  1111  of the connecting port  111 . The connecting port  111  of the circuit board  11  extends through the inner shell  13 . The switch  112  controls usage status of the circuit board  11 . 
     As disclosed in  FIG. 6 , the shielding layer  14  covers the inner shell  13  and the circuit board  11 . The shielding layer  14  is welded on the shielding net layer  122  of the two core wires  121  to be electrically connected to the shielding net layer  122 . In the first embodiment, the shielding layer  14  is a copper foil shielding tape, and the connecting port  111  of the circuit board  11  extends through the shielding layer  14 . 
     As disclosed in  FIG. 7 , the outer shell  15  is mounted on the shielding layer  14  by injection molding to cover the shielding layer  14 , and the connecting port  111  of the circuit board  11  extends through the outer shell  15 . In the first embodiment, the outer shell  15  further comprises two third through holes  151 . The two third through holes  151  of the outer shell  15  are respectively formed through the two second through holes  131  of the inner shell  13 . The two third through holes  151  of the outer shell  15  respectively communicate with the two first through holes  1111  of the connecting port  111 . 
     The connector  10  of the PROFIBUS-DP further comprises two fastening elements  16 . The two fastening elements  16  are respectively mounted through the two third through holes  151  and the two first through holes  1111  to pass through the outer shell  15 , the inner shell  13 , and the connecting port  111 . Therefore, when the connector  10  of the PROFIBUS-DP is connected to a PROFIBUS device (not shown), such as a PROFIBUS master, a PROFIBUS slave, or a PROFIBUS repeater, the connecting port  111  may be connected to a connector port of the PROFIBUS device. Further, the two fastening elements  16  may be screwed into the PROFIBUS device through the two third through holes  151  and the two first through holes  1111 , and the connector  10  may be firmly fixed on the PROFIBUS device. 
     With reference to  FIGS. 8 and 9 , a second embodiment of the connector  20  of the PROFIBUS-DP comprises a circuit board  21 , two communicating cables  22 , an inner shell  23 , a shielding layer  24 , and an outer shell  25 . 
     With reference to  FIG. 11 , at least one connecting port  211  is adapted to be mounted on the circuit board  21 . In the second embodiment, two connecting ports  211  are mounted on the circuit board  21 , and the two connecting ports  211  are respectively mounted on two opposite ends of the circuit board  21 . Each of the two communicating cables  22  comprises two core wires  221  and a shielding net layer  222 . The two core wires  221  are coated by the shielding net layer  222 , such that the shielding net layer  222  covers the two core wires  221 . Ends of the two core wires  221  are electrically connected to the circuit board  21 . 
     The inner shell  23  is mounted on the ends of the core wires  221  by injection molding to cover the ends of the core wires  221  of the two communicating cables  22 . The shielding layer  24  covers the inner shell  23  and the circuit board  21 , and is electrically connected to the shielding net layers  222  of the two communicating cables  22 . 
     The outer shell  25  is mounted on the shielding layer  24  by injection molding to cover the shielding layer  24 . The two connecting ports  211  extend through the inner shell  23 , the shielding layer  24 , and the outer shell  25 . 
     A difference between the first embodiment and the second embodiment is that the second embodiment of the connector  20  comprises two connecting ports  211 . One of the two connecting ports  211  may be connected to the connecting port of the PROFIBUS-DP device, and the other one of the two connecting ports  211  may be connected to another connector  20  or another connecting port of other PROFIBUS-DP device. Therefore, a topology of the PROFIBUS may be more easily constructed. 
     With reference to  FIGS. 10 to 14 , a manufacture method of the second embodiment of the connector  20  of the PROFIBUS-DP is shown. As disclosed in  FIG. 10 , the circuit board  21  is provided. Two connecting ports  211 , a switch  212 , multiple conductive bars  213 , two connecting tubes  214 , and any other necessary elements (not shown in the figures) are mounted on the circuit board  21 . The two connecting ports  211  are respectively mounted on two opposite ends of the circuit board  21 , and each of the two connecting ports  211  comprises two first through holes  2111 . The two connecting tubes  214  are mounted between the two connecting ports  211 , and two of the first through holes  2111  that are of the two different connecting ports  211  communicate with each other through one of the two connecting tubes  214 . As disclosed in  FIG. 9 , the inner shell  23  comprises two second through holes  231 , and the two connecting tubes  214  are respectively mounted in the two second through holes  231  of the inner shell  23 . 
     As disclosed in  FIG. 11 , the ends of the two core wires  221  of the two communicating cables  22  may be welded on the conductive bars  213  of the circuit board  21 . 
     As disclosed in  FIG. 12 , the inner shell  23  is mounted on the ends of the core wires  221  by injection molding to cover the circuit board  21  and the ends of the two core wires  221  of the two communicating cables  22 , and further to cover the switch  212 , the conductive bars  213 , the two connecting tubes  214 , and any other necessary elements mounted on the circuit board  21 . In the second embodiment, the two connecting ports  211  of the circuit board  21  are respectively extended through the inner shell  23 . The switch  212  controls usage status of the circuit board  21 . 
     As disclosed in  FIG. 13 , the shielding layer  24  covers the inner shell  23  and the circuit board  21 , and the shielding layer  24  is welded on the shielding net layer  222  of the two core wires  221  to be electrically connected to the shielding net layer  222 . In the second embodiment, the shielding layer  24  is a copper foil shielding tape, and the two connecting ports  211  of the circuit board  21  extend through the shielding layer  24 . 
     As disclosed in  FIG. 14 , the outer shell  25  is mounted on the shielding layer  24  by injection molding to cover the shielding layer  24 , and each of the two connecting ports  211  of the circuit board  21  extends through the outer shell  25 . In the second embodiment, the connector  20  of the PROFIBUS-DP further comprises two fastening elements  26 . The two fastening elements  26  are respectively mounted through the first through holes  2111  of the connecting ports  211  and the two connecting tubes  214  to pass through the two connecting ports  211 , the outer shell  25 , and the inner shell  23 . Therefore, when the connector  20  is connected to a PROFIBUS device (not shown), such as a PROFIBUS master, a PROFIBUS slave, or a PROFIBUS repeater, one of the two connecting ports  211  may be connected to a connector port of the PROFIBUS device. Further, the two fastening elements  26  may be screwed into the PROFIBUS device, and the connector  20  may be firmly fixed on the PROFIBUS device. 
     With reference to  FIG. 15 , the first embodiment of the connector  10  and the second embodiment of the connector  20  may be connected through the two communicating cables  12 ,  22 . The first embodiment of the connector  10  and the second embodiment of the connector  20  may be respectively connected to two PROFIBUS devices. Therefore, the two PROFIBUS devices may communicate with each other to transmit data, and then, the topology of the PROFIBUS may be constructed. 
     Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only. Changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.