Tap device of cable broadcasting system

• US 6,804,828 B1
• Filed: 12/02/1999
• Issued: 10/12/2004
• Est. Priority Date: 12/03/1998
• Status: Expired due to Fees

• Current Assignee: Masprodenkoh Kabushikikaish, Masprodenkoh Kabushikikaisha.
• Original Assignee: Masprodenkoh Kabushikikaisha.
• Inventors: Shibata, Eiji
• Primary Examiner(s): Srivastava, Vivek
• Assistant Examiner(s): HUYNH, AN SON PHI
• Application Number:
  US09/452,781
• Time in Patent Office: 1,776 Days
• Field of Search: 725/127, 725/149, 725/94, 725/116, 725/119, 725/130, 725/126, 725/118, 725/148, 725/128, 725/129, 333/166, 333/101, 333/258, 333/262, 323/351
• US Class Current: 725/149
• CPC Class Codes: H01P 1/10 for switching or interrupting in systems using reflection or reradiation of radio, acoustic or other waves G01S7/034
• CPC Class Codes: H01P 5/12 Coupling devices having more than two ports H01P5/04 takes precedence
• CPC Class Codes: H04H 20/79 using downlink of the CATV systems, e.g. audio broadcast via CATV network

Abstract

A part of transmission signal is branched by a directional coupler, and split by a splitting circuit, so that the transmission signal can be outputted to the subscribers'"'"' terminal devices via branched output terminals. Latching relays disposed in signal paths to the branched output terminals from the splitting circuit can set the output/stop of the transmission signal to the terminal devices. A control circuit switches the connected/disconnected state of the relays in response to the command signal from the center apparatus. When an operation switch is turned on, all the relays are placed into the connected state. As a result, after the installation of the tap device, by operating the operation switch, the broadcasting signal can be distributed to the terminal devices before the command signal is received.

Claims

1. A tap device of a cable broadcasting system, connected to a transmission line leading to a terminal side from a center apparatus for branching a part of a transmission signal running through the transmission line to a subscriber terminal device, comprising:

a directional coupler for branching the part of the transmission signal running through said transmission line and transmitting the branched transmission signal to each of a plurality of signal paths leading to corresponding branched output terminals;

a plurality of latching relays, each latching relay being disposed on a corresponding signal path for switching the signal path to one of a connected state and a disconnected state to a corresponding branched output terminal;

a receiving circuit for receiving from the transmission line a command signal indicating whether the latching relay is to be switched to the connected state or to the disconnected state to provide the branched transmission signal to the corresponding branched output terminal; and

a control means for controlling the connected and disconnected state of each latching relay and corresponding signal path to a corresponding branched output terminal, including

a control circuit connected from the receiving circuit and responsive to the command signal for providing a plurality of latching relay control signals to the latching relays to control the connected and disconnected state of each latching relay,

a manual operation switch for providing a manual output command to the control circuit,

the control circuit being responsive to the manual output command to generate the latching relay control signal to each of the plurality of latching relays directing each of the latching relays into the connected state to provide the branched transmission signal to each of the branched output terminals, wherein

if the control circuit receives the command to switch a plurality of latching relays, the control circuit energizes a plurality of targeted latching relays in sequence, instead of energizing the same simultaneously, to place each of the plurality of latching relays in the connected and disconnected states in sequence.

2. The tape device of the cable broadcasting system according to claim 1, further comprising:

a splitting circuit for splitting the transmission signal branched by said directional coupler into a plurality of signals, and outputting the split transmission signals via a plurality of branched output terminals, wherein

the latching relays are disposed in a plurality of signal paths leading from the splitting circuit to the plurality of branched output terminals.

5. The tap device of the cable broadcasting system according to claim 1, wherein

if the control circuit receives the command signal from the receiving circuit to switch a plurality of latching relays or the manual output command, the control circuit energizes the plurality of targeted latching relays in sequence, instead of energizing the same simultaneously, to place each of the plurality of latching relays in the connected and disconnected states in sequence.

7. The tap device of the cable broadcasting system according to claim 1, wherein

if the control circuit receives the command signal to switch the plurality of latching relays, the control circuit energizes a plurality of targeted relay coils corresponding to the latching relays in sequence, instead of energizing the same simultaneously, to place each of the plurality of latching relays in the connected and disconnected states in sequence.

10. The tap device of the cable broadcasting system according to claim 5, wherein

if the control circuit receives the command signal from the receiving circuit to switch the plurality of latching relays on the manual output command, the control circuit energizes a plurality of targeted relay coils corresponding to the latching relays in sequence, instead of energizing the same simultaneously, to place each of the plurality of latching relays in the connected and disconnected states in sequence.

3. A tap device of a cable broadcasting system, connected to a transmission line leading to a terminal side from a center apparatus for branching a transmission signal to branched output terminals, comprising:

a plurality of signal paths providing the branched transmission signal to corresponding branched output terminals,

a plurality of latching relays for connecting for disconnecting corresponding ones of the signal paths to corresponding ones of the branched output terminals, each latching relay being disposed on a corresponding signal path for switching the signal path to one of a connected state and a disconnected state to a corresponding branched output terminal, and the latching relays are placed in the connected and the disconnected states by a single command signal which produces successive energization of the latching relays controlled by that single command signal;

a control means responsive to the single command signal from the transmission line for controlling the successive energization of each of the latching relays controlled by that single command signal, and

a manual operation switch for providing a manual output command to the control means,

the control means responsive to the command signal for placing each latching relay in a connected or disconnected state and to the manual output command to place each latching relay into the connected state.

6. The tap device of the cable broadcasting system according to claim 3, wherein

if the control means receives the single command signal to switch the plurality of latching relays to the connected state or disconnected state or the manual output command to place each of the plurality of latching relays in the connected state, the control means switches a plurality of targeted latching relays in sequence, instead of switching the same simultaneously, to place each of the plurality of latching relays in the connected and disconnected states in sequence.

8. The tap device of the cable broadcasting system according to claim 3, wherein

the plurality of latching relays are placed in the connected and the disconnected states by the single command signal which produces successive energization of relay coils corresponding to the latching relays controlled by that single command signal;

and

the control means responsive to the single command signal from the transmission line controls the successive energization of each of the relay coils corresponding to the latching relays, in sequence instead of energizing the same simultaneously, controlled by that single command signal.

11. The tap device of the cable broadcasting system according to claim 6, wherein

if the control means receives the single command signal to switch the plurality of latching relays to the connected state or disconnected state or the manual output command to place each of the plurality of latching relays in the connected state, the control means switches a plurality of targeted relay coils corresponding to the latching relays in sequence, instead of switching the same simultaneously, to place each of the plurality of latching relays in the connected and disconnected states in sequence.

4. A tap device of a cable broadcasting system, connected to a transmission line leading to a terminal side from a center apparatus for branching a part of a transmission signal running in a forward direction through the transmission line to a subscriber terminal device, comprising:

a directional coupler for branching a part of the transmission signal running through said transmission line and transmitting the branched transmission signal to each of a plurality of forward signal paths leading to corresponding branched output terminals;

a plurality of latching relays, each of the plurality of latching relays being disposed ion a corresponding forward signal path for switching the signal path to one of a connected state and a disconnected state to a corresponding branched output terminal;

a receiving circuit for receiving a command signal indicating whether the plurality of latching relays are to be switched to the connected state or to the disconnected state to provide the branched transmission signal to the corresponding branched output terminal; and

a control means for controlling the connected and disconnected state of each latching relay and corresponding forward signal path to a corresponding branched output terminal, including

a control circuit connected to the receiving circuit and responsive to the command signal for providing a plurality of latching relay control signals to the plurality of latching relays to control the connected state and disconnected state of each latching relay, the control circuit sequentially generating a sequence of the latching relay control signals to each of the plurality of latching relays in sequence and directing each of the latching relays into the connected state and disconnected state; and

a splitting circuit for splitting the transmission signal branched by said directional coupler into a plurality of signals, and outputting the split transmission signals via a plurality of branched output terminals, the latching relays are disposed in a plurality of signal paths leading from the splitting circuit to the plurality of branched output terminals.

9. The tap device of the cable broadcasting system according to claim 4, wherein

the control circuit sequentially generates a sequence of the latching relay control signals to each of a plurality of relay coils corresponding to the latching relays in sequence, instead of energizing the same simultaneously, and directs each of the latching relays into the connected state and disconnected state.