Load connector

Information

  • Patent Grant
  • 6334791
  • Patent Number
    6,334,791
  • Date Filed
    Wednesday, July 12, 2000
    24 years ago
  • Date Issued
    Tuesday, January 1, 2002
    23 years ago
  • Inventors
  • Examiners
    • Paumen; Gary
    • Nguyen; Phuong
    Agents
    • Dougherty & Troxell
Abstract
Load connector including a main body for connecting with output terminal of a distributor, a collar coaxially disposed in the main body and a circuit board coaxially disposed in the collar. The collar has a flange end section and an interface section. The interface section defines an annular groove for receiving the circuit board therein. The circuit board is formed with a through hole in which a central pin is disposed. The outer circumferences of the through hole and the circuit board are respectively electroplated with two annular conductive layers. A chip resistor or a film resistor is disposed between the two conductive layers. The above arrangement greatly shortens the internal using space of the load connector and has good impedance coupling so that an optimal electric appliance property can be achieved. An O-ring is disposed on outer side of the wall of the flange end section of the collar so as to achieve a moisture-tight seal between the load connector and the output terminal.
Description




BACKGROUND OF THE INVENTION




(1) Field of the Invention




The present invention relates to a load connector, and more particularly to a load connector in which a circuit board is disposed in the collar and the inner and outer circumferences of the circuit board are respectively electroplated with two annular conductive layers. A chip resistor or a film resistor is disposed between the two conductive layers to shorten the internal using space of the load connector and achieve an optimal electric appliance property.




(2) Description of the Prior Art




In television systems such as cable television system (CATV), closed-circuit television system (STV) and common antenna television system (MATV), coaxial cables are used to transmit the signals to wide customers. Referring to

FIGS. 1A and 1B

, generally, multiple distributors


10


are disposed on the main trunk of these television systems. The distributors


10


via coaxial cables transmit signals to the customers. However, the number of the customers will not be just equal to the number of the output terminals of the distributors. Therefore, a load connector


12


with impedance coupling is used to connect with the not used output terminal


11


to avoid leakage of the signals which will lead to signal interference. In order to eliminate the signal interference, the load connector is mounted on the not used output terminal to avoid impedance discoupling between the coaxial cable for outputting signals and the coaxial cable of the customers.




Such load connector


12


includes a main body


13


formed with an inner thread section


14


and a receptacle


15


. The inner thread section


14


is screwed on a not used output terminal


11


. A resistor


16


is positioned in the receptacle


15


. A lead


17


at rear end of the resistor


16


extends out of the main body


13


and fixedly soldered on the main body


13


. A lead


18


at front end of the resistor


16


extends out of the main body


13


to connect with a contact element of the not used output terminal


11


so as to form impedance coupling.




The requirement for receiving frequency has been higher and higher nowadays. The frequency has been increased from 550 MHz to 1000 MHz or higher. Therefore, the commercially available load connector must be applicable to high frequency. However, the resistor


16


mounted in the conventional load connector


12


is the widely used 75 Ω resistor which has considerably large volume. Therefore, the total length of the load connector


12


is increased relatively. In the case of burglarproof load connector or double-head (male-female head) load connector, the total length thereof will be even longer. The longer the total length of the load connector is, the smaller the back loss of the electric appliance achieved at high frequency is. Such back loss can hardly meet the requirement of U.S. electric appliance specification standard (SCTE) that the back loss should be over 30 dB. Therefore, the excessively long load connector will directly affect the video quality and can hardly meet the requirement of high frequency.




Therefore, it is necessary to provide a load connector which can achieve larger back loss of electric appliance and meet the requirement of high frequency.




SUMMARY OF THE INVENTION




It is therefore a primary object of the present invention to provide a load connector in which a circuit board is disposed in the collar. The inner and outer circumferences of the circuit board are respectively electroplated with two annular conductive layers. A chip resistor or a film resistor is disposed between the two conductive layers to greatly shorten the internal using space of the load connector and achieve a good impedance coupling. Accordingly, the total length of the load connector is shortened to achieve an optimal electric appliance property when connected with the distributor.




It is a further object of the present invention to provide the above load connector in which an O-ring is disposed on outer side of the wall of the flange end section of the collar, whereby when the load connector is connected with the output terminal of the distributor, the O-ring is compressed between the output terminal and the collar to achieve a moisture-tight seal.




The present invention can be best understood through the following description and accompanying drawings wherein:











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1A

is a perspective exploded view of a conventional distributor and load connector;





FIG. 1B

is a sectional view of a conventional load connector;





FIG. 2

is a sectional view of the load connector of the present invention;





FIG. 3

is a perspective exploded view of the load connector of the present invention;





FIG. 4

is a sectional view of the main body of the load connector of the present invention;





FIG. 5

is a sectional view of the collar of the load connector of the present invention;





FIG. 6A

is a plane view of a first embodiment of the circuit board of the present invention; and





FIG. 6B

is a plane view of a second embodiment of the circuit board of the present invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Please refer to

FIGS. 2 and 3

. The load connector


20


of the present invention includes a main body


21


, a collar


30


coaxially disposed in the main body


21


and a circuit board


40


coaxially disposed in the collar


30


. Referring to

FIG. 4

, the main body


21


is formed with a first tubular end section


22


, a second tubular end section


23


, a hexagonal body section


24


and a lateral end section


25


. The first tubular end section


22


is formed with an inner thread


26


and two annular sections


27


,


28


. The inner thread


26


is able to connect with an output terminal of a distributor and ends at an annular section


26


.




Referring to

FIG. 5

, the collar


30


has a flange end section


31


and an interface section


32


. The interface section


32


defines an annular groove


33


which is such dimensioned as to receive the circuit board


40


therein. The interface section


32


ends at an inner shoulder section


34


. The flange end section


31


defines a perforation


35


. A sealing member such as an O-ring


36


is disposed on outer side of the wall of the flange end section


31


.




Referring to

FIG. 6A

, the circuit board


40


is positioned in the annular groove


33


and fixedly soldered in the collar


30


. The circuit board


40


is formed with a through hole


41


which is such dimensioned as to receive therein a central pin


43


. The outer circumferences of the through hole


41


and the circuit board


40


are respectively electroplated with two annular conductive layers


42


. At least one chip resistor


44


or a donut-shaped film resistor


45


(as shown in

FIG. 6B

) is disposed between the two conductive layers


42


. When the central pin


43


is inserted into a contact element in the output terminal, an impedance coupling is formed.




When the inner thread


26


of the load connector


20


is connected with the output terminal of the distributor, the O-ring is compressed between the output terminal and the collar


30


to form a moisture-tight seal for preventing moisture from entering the connector


20


to interfere with the video quality.




In the load connector


20


of the present invention, the chip resistor


44


or film resistor


45


is associated with the circuit board


40


so as to greatly shorten the internal using space and thus change the total length of the load connector


20


. Accordingly, the back loss of electric appliance is over 30 dB and an optimal electric appliance property can be achieved to meet U.S. electric appliance specification standard.




The above embodiments are only used to illustrate the present invention, not intended to limit the scope thereof. Many modifications of the above embodiments can be made without departing from the spirit of the present invention.



Claims
  • 1. Load connector for connecting with output terminal of a distributor to form impedance coupling, comprising:a main body formed with an inner thread and annular section; a collar coaxially disposed in the annular section of the main body, having a flange end section and an interface section, the interface section defining an annular groove; and a circuit board coaxially disposed in the annular groove of the interface section, the circuit board being formed with a through hole for receiving therein a central pin, outer circumferences of the through hole and the circuit board being respectively electroplated with two annular conductive layers, at least one chip resistor or a film resistor being disposed between the two conductive layers.
  • 2. Load connector as claimed in claim 1, wherein an O-ring is disposed between the inner thread and the annular section of the main body, whereby when the load connector is connected with the output terminal of the distributor, the O-ring is compressed between the output terminal and the collar to form a moisture-tight seal.
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