JPH10271371A - Power-feeding device of tv camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a signal from being affected by external disturbances, when power is fed to a TV camera with a camera transmission track to transmit a video and an audio signals from the TV camera to a reception site and to simultaneously transmit a TV camera external synchronization signal and a control signal. SOLUTION: DC is fed to a TV camera 18 by a constant current with the camera transmission track. A rechargeable battery 10 for supplying the current required for an operation is provided with the TV camera 18, electric power of power consumption surrounding circuit such as a motor, a sensor, etc., connected with the TV camera 18 is supplied, and the TV camera 18 is operated when the constant current is turned off. The constant current is nearly equalized to the sum of the current consumed by the camera and constant charging current required for charging the rechargeable battery. In addition, when plural TV cameras, discriminated by discrimination data are connected to the reception site, the respective TV cameras are synchronized with the external synchronization signals generated for each vertical blanking cycle of the video signal, and signals are switched without hit at the reception site 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a TV camera device having a function of positioning an electric pan and tilt, that is, a motorized device such as a zoom lens used in a television (TV) camera.

[0002]

2. Description of the Related Art A TV camera device used for a monitor device is mounted on a remote control type electric pan-tilt head which positions the camera so that the camera can capture images from various angles. This TV camera uses a remotely controlled zoom lens and is mounted inside a case body having a windshield with an electric wiper mechanism and a fan or heater for cooling or heating the camera. The TV camera is remotely controlled and can be automatically repositioned by energizing all or some of the motors simultaneously.

The above-mentioned camera requires a power supply having a capacity sufficient to simultaneously supply power to the camera itself, each motor or all motors, and other peripheral devices. Therefore, the TV camera which is remotely operated and consumes power irregularly is supplied with power through a dedicated heavy power cable connected to a dedicated power supply, which requires labor and cost.

Also, a T-mount using a fixed or manually adjustable lens mounted on a fixed immobile mount.
V cameras do not consume power randomly. The above camera having a stable constant current drain supplies power to the camera using a transmission line laid between the camera and a monitor site (monitoring unit). The transmission line may be used to propagate an external synchronization signal from the monitor site to the camera.

The above device for externally synchronizing a TV camera sends an external synchronizing signal to a video (image) signal transmission line and locks an internal synchronizing signal generator of the TV camera via the transmitted external synchronizing signal. This is a device for transmitting an external synchronization signal from the external synchronization signal generator to the TV camera. Such a device is disclosed in U.S. Pat. No. 4,603,352.
And the contents of which are incorporated herein by reference.

When the monitor device employs a plurality of TV cameras, these TV cameras transmit video, audio and identification (ID) signals to a monitor site via a video transmission line, while control signals are transmitted by the same video transmission. Propagated from the monitor site to the camera via the track. A monitor device that employs such a plurality of TV cameras to transmit video, audio, and ID signals to a monitor site via the same transmission line and to transmit a control signal and an external synchronization signal to the camera is disclosed in US Pat. , 579, 060, the contents of which are incorporated herein by reference.

In such a device, when the video, audio, external synchronization, ID and control signals are propagated through the video transmission line together with the power for feeding the camera, the current drain in the transmission line is adjusted and stabilized. Otherwise, the transmission of the signal will cause disturbances.

When a current surge occurs due to the start of the motor and / or when a random current is supplied to the TV camera and any of its pan-tilt motor, zoom lens motor and / or other current-using peripheral devices, T
Neither of the V cameras can be powered via the video transmission line.

[0009]

An object of the present invention is to provide a TV set.
In order to transmit the video and audio signals generated by the camera together with the ID code for identifying the TV camera, the TV camera and its electric positioning device and other current consuming peripheral devices communicate between the TV camera and the receiving site (receiving unit). Power is supplied through an extended camera transmission line, and at the same time, an external synchronization signal and a control signal are propagated to the TV camera via the same common transmission line.

[0010]

SUMMARY OF THE INVENTION An apparatus for powering a TV camera via a camera transmission line according to the present invention includes a single or a plurality of TV cameras for processing an electrical information signal including a video signal, and a constant current for the TV camera. Or a plurality of current supply means for supplying the current, a single or a plurality of camera transmission lines for connecting each TV camera to each current supply means, and the plurality of the TV cameras by generating an external synchronization signal And external signal generating means for supplying the signal to the receiving means.

Each current supply means includes a circuit for supplying an information signal to a receiving site via a corresponding information transmission line. The receiving site may include a selection circuit for selecting one of the plurality of corresponding information transmission lines or switching from one information transmission line to another information transmission line. The selection and switching timing of the information signal in the selection circuit is performed in synchronization with the external synchronization signal.

Each camera transmission line includes a current supply means and a TV.
Corresponding to the combination with the camera, each TV camera is powered via a corresponding camera transmission line and transmits information signals to the receiving site. An information signal from each of the single or multiple TV cameras is sent to each current supply means. An information signal output from each current supply means is connected to a TV monitor via a single information transmission line or to one of a plurality of input terminals of a selection circuit of a reception site via a plurality of corresponding information transmission lines. do it.

The power supplied to the TV camera via the camera transmission line is a constant current, and is maintained at a predetermined level by a current adjusting circuit provided in the current supply means. The predetermined current is the sum of the constant current consumed by the TV camera circuit and the additional constant current supplied to the rechargeable battery connected to the TV camera. Charged batteries provide variable or random current drains and / or current surges when providing energy to drive motors and other peripherals. Thus, the camera can be remotely controlled, or either position motors or other peripherals that generate current drain individually, or all of the motors and other peripherals without disturbing the propagation signals on the camera transmission line. It can be automatically activated at the same time. The charged battery can also supply power to the camera circuit when the constant current supplied to the camera is cut off.

Each current supply means includes a signal separation / injection circuit for removing an information signal generated by the TV camera which has propagated from the DC through the camera transmission line, and outputs the separated information signal to an information signal output terminal. Supply. The external synchronization signal, along with the control signal generated by the receiving site, passes through the information signal output terminal and the signal separation / injection circuit in the reverse direction and is supplied to the TV camera via the camera transmission line, or a separate control and / or Alternatively, the signal is supplied directly to the camera transmission line via the injection circuit through the external synchronization terminal.

Each TV camera includes a DC separation circuit for separating DC from control and external synchronization signals generated by the receiving site and supplying the separated external synchronization and control signals to an external synchronization and control signal processing circuit. DC isolated
Is to the TV camera circuit via the constant current control circuit,
Supplied to the rechargeable battery via the battery control circuit. Each TV camera further includes a video signal injection circuit, and may also include an ID code and a video signal injection circuit for injecting video, audio and ID signals into the camera transmission line. When injected into the camera transmission line, the signal becomes a combined information signal and is sent to the receiving site via the current supply means and the information transmission line.

The switching of the information signal is performed precisely in synchronization with the vertical synchronization timing by an external synchronization signal, thereby realizing a non-blocking synchronization process. The reproduced video image is output when the power is turned on or when the switching operation is performed and immediately thereafter. No disturbance will occur.

According to the present invention, the receiving site passes through a plurality of corresponding camera transmission lines and is connected to a plurality of TV cameras via the information transmission line. , And is synchronized with an external synchronization signal. Therefore, even if many TV cameras are interposed,
The information transmission line connecting the current supply means and the receiving site can be synchronously switched by a simple device without causing disturbance in the reproduced video image.

Each TV camera includes an internal synchronizing signal generating circuit for generating an internal synchronizing signal synchronized with the external synchronizing signal.

According to the present invention, the external synchronization signal is a pulse signal having a voltage level higher than the maximum voltage level of the composite video signal or lower than the minimum voltage level. The external synchronization generator includes a circuit for injecting an external synchronization signal into the information transmission line connecting the current supply means and the reception site or directly into the information transmission line. Each TV camera is
And a level comparing circuit for extracting the external synchronization signal by comparing the external synchronization pulse signal with a reference signal having a predetermined voltage, and supplying the extracted external synchronization signal to the internal synchronization signal generation circuit. Since the external sync pulse is generated during the vertical blanking cycle of the video signal,
The external synchronization signal can be transmitted through the same transmission line for transmitting the video signal without affecting the video signal.

In a preferred embodiment, the receiving site may include circuitry for removing external synchronization signals from the output signal, which is preferably provided to the receiving site via a corresponding information transmission line. Therefore, since the external synchronization signal is removed from the video signal processed by the receiving site, the external synchronizing signal can completely receive the video signal without affecting the receiving site circuit.

In the preferred embodiment, each TV camera generates an ID code signal corresponding to the ID number assigned to each TV camera, and outputs the ID code signal to the video signal supplied to the receiving site.
An ID code generator for injecting the D code signal is further included. The receiving site further determines from the output signal of the selection circuit
An ID code signal processing means for extracting a D code signal and supplying a signal corresponding to the extracted ID code signal to a video signal processing means is included.

The ID code signal processing means is preferably
A memory for storing identification data of each assigned code number, a decoding circuit (decoder) for decoding an ID code signal extracted from an output signal of the selection circuit for generating a decoded signal, A controller for reading the ID data based on the read ID data and superimposing the read ID data on the video signal. Therefore, the processed video signal can be identified by the ID code signal processing means for verification of the TV camera transmitting the video signal, thereby providing a basis for realizing error-free control of the TV camera.

The apparatus according to the present invention further includes a control circuit for generating and supplying a control signal in which the coding control command is decoded by the decoding circuit and mixed with the supplied ID code signal to control the TV camera. Is also good. The coding control command is supplied to operate the TV camera only when the ID code signal mixed with the control signal corresponds to the ID number assigned to the TV camera to be controlled. As described above, only a specific TV camera having an ID code extracted and decoded by the control circuit in the control process is assigned an ID number that matches the ID code extracted from the control signal supplied from the control circuit. I have. Therefore,
The control of the specific TV camera can be verified.

[0024] The receiving site may further include a control signal driver for injecting a control signal into one or more information transmission lines or camera transmission lines in a direction opposite to the propagation direction of the video signal.

The control signal is transmitted to a TV camera during a vertical blanking (return blanking) period of a video signal by an information transmission line connecting a current supply means and a receiving site or a control terminal of the current supply means. And injected directly into the camera transmission line via the injection circuit. The TV camera has control signal processing means for extracting a control signal from the camera transmission line and supplying the extracted control signal only when the ID code signal mixed with the control signal matches the ID code number assigned to the camera. Further, it may be included. Since the control signal is transmitted during the blanking period of the video signal, the control signal can be transmitted from the receiving site to the TV camera through the common information transmission line without causing disturbance in the video signal.

As described above, both the video signal and the control signal can be bidirectionally transmitted between the receiving site and the TV camera via the current supply means and the common transmission line.

Each TV camera preferably injects the audio signal into the video signal and converts the mixed signal to a corresponding T
It further includes signal mixing means for generating a mixed signal composed of a video signal and an audio signal by supplying the signal to the receiving site via the current supply means and the information transmission line through the V camera transmission line. Thus, the mixed video and audio signals are transmitted between the TV camera and the receiving site via a common transmission line.

[0028] Each current supply means or receiving site may further include audio signal reading means for outputting an audio signal by reading an audio portion from the mixed signal.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a preferred embodiment in which the present invention is applied to a closed-circuit television (TV) device such as a monitor device, in which a single TV camera is fed via an information signal transmission line as a preferred embodiment. 1 shows an apparatus for performing the above. The information signal in the following description may be composed of only a video signal, and a video, audio and / or identification signal transmitted from the TV camera to the receiving site (receiving unit), and transmitted from the receiving site to the TV camera. Or a combination of a camera control signal and / or an external synchronization signal. A video signal in the following description is composed of a part of a composite video signal or a composite video signal or a digital video signal.

Referring to FIG. 1, the power supply device of the TV camera 1 transmits and receives information signals to and from a TV camera 18 for transmitting information signals to and from a receiving site.
And a camera transmission line 16 for transmitting an information signal between the camera and the current supply means 26 and for transmitting a constant current from the current supply means 26 to the TV camera 18. A TV monitor 92 for displaying a video image, a video cassette recorder (VCR) 94 for recording a video image, and a camera control circuit (controller) for transmitting a control command for remotely controlling the TV camera 18. 100 and TV camera 18
From a rechargeable battery 10 that provides the necessary energy source for the operation of the motor or other current consuming peripheral device and an information transmission line 12 for propagating information signals between the current supply means 26 and the receiving site. Become.

FIG. 2 shows a device 11 for supplying power to a plurality of TV cameras via an information signal transmission line as a preferred embodiment in which the present invention is applied to a closed circuit TV device such as a monitor device.

Referring to FIG. 2, a plurality of TV cameras 11
The device for powering a plurality of T
A plurality of current supply means 26 for transmitting / receiving a transmitted information signal to / from a receiving site and supplying a constant current to the TV camera 18, and transmitting the information signal between the camera and the current supply means 26 A plurality of camera transmission lines 16 for transmitting a constant current from the constant current supply means 26 to the TV camera 18, a single or a plurality of TV monitors 92 for displaying a video image, and each TV camera 18. Rechargeable batteries 10 to provide the energy source required for the operation of the motor or other current consuming peripheral device, and an information transmission line for propagating information signals between the plurality of current supply means 26 and the receiving site. 12, a selection circuit (selector) 30 for selecting an information signal, a TV camera 18,
External synchronization generating means 20 for synchronizing the selector 30 and the control circuit (controller) 100; a synchronization signal clipping circuit 34 for clipping and removing a synchronization pulse from the information signal; a motor of the TV camera 18 or other components; And a control circuit (controller) 100 for transmitting a control command for remotely operating the current consuming peripheral device. The control circuit (controller) 100 can also generate control commands to the TV camera for adjusting and setting up the TV camera function or circuit independent of the current consuming peripheral device.

Each information transmission line 12 is connected to the current supply means 2.
6, the number of camera transmission lines 16 and the number of TV cameras 18. The information transmission line 12 in FIG. 1 is connected at one end to a control circuit (controller) 100 and a monitor 92. In contrast, each information transmission line 12 in FIG.
The selection circuit 30 is connected to each input of the selection circuit 30 and / or the monitor 92, and the selection circuit 30 is located at the reception site. The other end of each transmission line 12 is connected to an information signal output terminal of a current supply means 26 arranged somewhere between the receiving site and the TV camera. The current supply means is connected to the selector 30.
, Or may be arranged at the receiving site. In this case, the information transmission line 12 is an internal connection line of the receiving site. Monitor 92, video cassette recorder (VCR) 94, external synchronization generating means 20, and control circuit 3
2 are all installed in the reception site or its vicinity or in the monitor room. On the other hand, the TV camera 18 is mounted at various positions for capturing an image of a nearby or remote place. Each TV camera 18 is connected to a current supply means 26 via a camera transmission line 16 using a video signal transmission cable such as a coaxial cable or a twisted pair.

The current supply means 26 shown in FIG. 5, which is supplied by an unregulated DC power supply or a rectified AC power supply via an input terminal 28, employs a well-known constant current regulator 27 to provide the TV camera 18 with a camera power consumption. A constant current substantially equal to the sum of the constant charging current required for charging the rechargeable battery 10 shown in FIGS. The current for charging the battery is shown in FIG. 5 so that the rechargeable battery is fully charged for operation of the positioning motor and other current consuming peripherals such as heaters, wipers, glass washers, cooling fans, and the like. Current adjuster (regulator) 27
A is set to a predetermined calculated value via A. The rechargeable battery 10 includes nickel / nickel having different sizes and power capacities.
A cadmium battery or the like may be used, and another battery having a different type and capacity may be selected instead. The battery 10 is installed inside the camera housing or at a camera site, and is connected to the TV camera via a separate wire. The rechargeable battery may be used to supply power to the TV camera circuit when power to the current supply means is cut off.

As shown in FIG. 3, the camera transmission line includes a DC / signal separation circuit 17 for separating DC and signals.
It is connected to the. The separation circuit 17 includes a well-known coupling capacitor for coupling a signal and blocking DC from a signal processing circuit, and a well-known RF filter for removing a signal from DC. A signal transformer for reading out an information signal from the DC;
An RF trap for removing the information signal from the DC line may be used. The filtered DC line is a separation circuit 1
7 to the current control circuit 2. Current control circuit 2
Includes a dummy load DL that replaces the battery charging current when the battery polarity is reversed connected to the battery terminal 9 or when the battery 10 is disconnected.

When the polarity of the battery is reversed or the battery is disconnected, there is no battery charging current, so that an excessive current is supplied to the TV camera by the adjusted constant current supplied to the TV camera. TV camera 18
May be impaired. To prevent such damage,
The current control circuit 2 shown in FIG. 4 is supplied from the battery control circuit 8 together with a “no charge” signal for connecting a pseudo load DL that discharges a current corresponding to a charging current, so that an appropriate constant current is supplied to the TV. Supplied to the camera circuit.

The current control circuit 2 may employ a switching transistor for connecting the pseudo load resistor DL,
The transistor switching signal is a high / low signal supplied from the battery control circuit 8. As can be seen from FIG. 4, the battery control unit 8 includes a discharge check circuit 5 for checking the voltage supply of the battery, a reverse polarity check circuit 4 for checking the polarity connection of the battery, A charge cutoff switch SW1 for cutting off a charging current when connected, an output switch SW2 for cutting off an output to prevent disturbance of information signal propagation, two diodes D1 and D2, and a charging current resistor R1 and a zener diode D3 for controlling the current flow.

The discharge check circuit 5 and the reverse polarity check circuit 4 receive a reference signal from the charging line 3A and the battery terminal when the battery 10 is disconnected, discharged or reversely connected, and output a "closed" signal to the output switch SW2. Causes
Accordingly, the output current is cut off to prevent the consumption of random current from the charging line 3A, and the disturbance of the information signal flow due to the unstable current drain at the time of the discharge state, connection of the reverse polarity battery or disconnection of the battery is prevented. Similarly, a reverse connected battery is prevented from having a wrong polarity output that would cause a motor or other current consuming peripheral to fail and / or malfunction. The reverse polarity check circuit 4 generates a "reverse polarity" signal for turning off the charge switch SW1 in order to prevent damage to the battery 10 in the case of reverse polarity connection. The D1 diode prevents reverse unwanted current from the battery to the camera circuit when the current supply means 26 is switched off, and the resistor R1
Limits the current to the battery, and D2 / D3 protects the battery from overvoltages and surges. However, there are many well-known device and component options for preventing battery polarity connections, current direction and flow, current surge and overvoltage.

As the discharge check circuit 5 and the reverse polarity check circuit 4, a well-known differential or voltage comparison circuit may be employed for level detection.
And an output cutoff switch SW2 is a switching transistor,
Photocouplers, relays or other well-known circuit breakers may be employed. The battery 10 shown in FIG. 4 supplies the current to the output terminal 7 via the output cutoff switch SW2. As shown in FIG. 3, the output terminal is connected to the motor drive circuit 6 to power the motor of the camera 18 and other current consuming peripherals, and is controlled by the regulated constant current supplied to the TV camera circuit. Power is supplied to the switch SW3 which is switched to supply power to the TV camera circuit by the rechargeable battery when there is no regulated constant current.

The current supply means 26 is connected to the camera transmission line 16.
The information signal is received from the corresponding TV camera 18 via the information transmission line 12, and the received signal is transmitted to the input of the selector (selector) circuit 30 via the information transmission line 12. Therefore, the plurality of current supply units 26 act as relay circuits to transmit information signals to the inputs of the plurality of selectors 30 via the information transmission line 12. A selector circuit 30 including a plurality of electronic switches corresponding to the information transmission line 12 is included in the reception site 14, receives information signals transmitted from the plurality of TV cameras 18, and receives one or more electronic switches. The switch is turned on to connect one or more information transmission lines to a single or multiple monitors 92.
Alternatively, it is connected to a video cassette recorder 94. Monitor 9
2 may be directly connected to one of the information transmission lines 12 to display a corresponding signal of the TV camera 18.
Thus, one or more information signals transmitted via the information transmission line 12 are selected and selected from the selection circuit 30 to the monitor 92 or VCR 94, or directly to the monitor and / or V
Can be sent to CR. The selector 30 of FIG. 2 illustrates a mechanical selector switch, but may be a well-known IC such as an electronic multiplexer or matrix switch with multiple outputs that can be independently selected for which output to which input. .

The frequency of the external synchronization signal P1 shown in FIG. 7 is preferably the frame frequency or the field scan (field sc).
anning) the vertical frequency of the video signal generated by the TV camera 18 having a frequency. For example, NTSC (National Television System Commite
In the case of the method e), the frame frequency is 30 Hz and the field frequency is 60 Hz. In this case, the frequency of the external synchronization pulse P1 is a frame frequency of 30 Hz and a frequency of 60 Hz.
Field frequency. However, the external synchronization pulse train is composed of vertical and horizontal scanning frequencies and is transmitted during the corresponding vertical and horizontal blanking periods.

As shown in FIG. 7A, the time when the external synchronization signal P1 is generated is determined by the vertical synchronization pulse generated during the vertical blanking period of the video signal transmitted from the TV camera 18 shown in FIG. Is next to. Therefore, the external synchronization signal P1 is transmitted to the TV camera 18 via the information transmission line 12 and via the camera transmission line 16 for transmitting the video signal without affecting the video signal. The voltage level of the external synchronization signal P1 is preferably made higher than the composite video signal. However, the voltage level of the external synchronization signal P1 may be lower than the composite video signal.

In the following description, a frame external synchronization pulse having a voltage level higher than the white level of the video signal, particularly a frame external synchronization pulse corresponding to the phase of the second field, is used as the external synchronization signal P1.

In the embodiment illustrated in FIG.
The camera 18 is a TV camera operated in synchronization with the external synchronization signal P1. As such a TV camera, a known TV camera synchronized with an external synchronization signal having a higher or lower voltage level than the information signal may be used as disclosed in U.S. Pat. No. 4,603,352. .

Each TV camera 18 has 1, 2, 3. . . n
And an identification (ID) number for generating an identification (ID) code to be injected into the video signal during the vertical blanking period.

Each TV camera 18 includes a circuit for generating a code signal corresponding to the ID code, and a circuit for generating a composite signal in which the code signal is injected into a video signal. Such a device is disclosed in U.S. Pat. No. 4,943,8.
No. 64, which is hereby incorporated by reference. Therefore, each information signal received by the receiving site 14 includes the ID code.

As shown in FIG. 6, each receiving site 14
Is a pulse signal P shown in FIG. 7B synchronized with the external synchronization signal P1 transmitted from the external synchronization signal generation circuit 31.
2 is included.
The external synchronizing signal driving circuit 32 is
1 receives the pulse signal P1 supplied from the device 1 and injects the pulse signal P1 into the information signal transmission line 12.

Instead of injecting the pulse signal P1 into each information transmission line 12, the injection circuit 32 injects the external synchronization signal P1 into each current supply means 26, and further injects the pulse P1 into each camera transmission line 16. It may be. As shown in FIG. 5, the current supply means 26 is connected to the camera transmission line 1.
6 includes an information signal separation / injection circuit 21 for separating an information signal from the DC supplied to the DC transmission line 6 or for injecting the information signal into the camera transmission line 16. The signal separation circuit is similar to the DC separation circuit 17 shown in FIG.
Signal isolation is achieved via a signal transformer or coupling capacitor that blocks the DC component present at Therefore, the external synchronization signal injection circuit 3 of the reception site 14 shown in FIG.
The external synchronization pulse P1 supplied from 2 is sent to the external synchronization input terminal 23 and injected into the camera transmission line 16 via the signal separation / injection circuit 21.

The synchronizing pulse clipping circuit 34 shown in FIG. 2 clips the pulse P1 and uses the timing signal P2 to transmit a video signal not including the synchronizing signal P1 to the receiving line 35 and the TV monitor 92. It is provided to clip the synchronization pulse P1 from a signal supplied from any one of the transmission lines 12 or via the output of the selector 30 via the synchronization pulse clipping circuit 34.

The synchronization pulse clipping circuit 34 receives the signal shown in FIG. 7A from the information transmission line 12 and the timing signal P2 shown in FIG. 7B from the pulse shaping / timing circuit 33. Since signal P2 activates the clipping circuit during its duration, clipping circuit 34 clips the entire signal portion of the signal currently vacated at its terminals onto the black level Vb of the video signal during the period of signal P2. . Since the duration of the signal P2 covers the period of the external synchronization pulse P1, the external synchronization signal P1
Is removed from the composite video signal transmitted to the receiving site 14 by the clipping circuit 34 as shown in FIG. Although the pulse P2 shown in FIG. 7B is a positive pulse, the clipping of FIG. 6 is performed using another synchronized pulse size and polarity that matches the pulse P1 of FIG. 7A. The circuit 34 may be activated.

Therefore, the external synchronization signal P1 is transmitted from the transmission line 1
2 is removed by the clipping circuit 34 even if it is present in the video signal supplied from the TV camera 18 via Therefore, the synchronization signal P1 injected into the information transmission line 12 is synchronized with the TV camera 18 and does not cause a reception error at the reception site 14. Instead of placing a clipping circuit 34 at the output of the selector 30, a plurality of clipping circuits 34 can be included in each camera transmission line 16 or each information transmission line 12.

The controller 10 of the receiving site 14 shown in FIG.
0 is similar to the controller 100 at the receiving site 14 in FIG.
Generates a selection signal for selecting the TV camera 18 via the selector 30 which is not required from the controller 100 of the reception site 14 in FIG. The receiving site 14
A sync separation circuit 46 for separating the horizontal and vertical sync signals H and V from the composite video signal supplied to the information transmission line 12 or the reception line 35 is included. Controller 1
00 generates a control signal for operating the corresponding TV camera 18 at a predetermined time based on the separated synchronization signals H and V. The counter 52 is provided for counting the number of horizontal scanning lines supplied from the sync separator 46 in each frame or field. The control signal processing is controlled by the gate circuit 54 for generating a gate signal when the count value of the counter is a predetermined value, and the gate signal for injecting the control signal supplied from the controller 100 into the video signal of the selector output pole. A buffer circuit 56 is also included. The control signal is a signal separation / injection circuit 21
May be injected into the video signal of each information transmission line 12 or directly into each control signal output 22 of the current supply means shown in FIG.

In a preferred embodiment of the invention, the injection circuit may include a mixer circuit for injecting the code signal into the mixed composite video signal. Such a mixer circuit is disclosed in U.S. Pat. No. 4,989,085, which is hereby incorporated by reference.

The control command generated by the controller 100 is a control code for executing on / off switching of the wiper, up / down tilting, left / right panning, telescopic-wide zooming, etc., or start or stop of video signal transmission. A command may be included. Also, the control signal combines a control code corresponding to the control command with an ID code assigned to each TV camera 18. Further, the control signal is
The signal is injected into the information transmission line 12 by the buffer circuit 56 in FIG. 6 at a predetermined time during the vertical blanking cycle. The injection timing of the control signal into the information transmission line 12 is different from the injection timing of the external synchronization signal into the information transmission line 12.

As is apparent from the above description, the external synchronization signal and the control signal are transmitted from the receiving site to the corresponding TV camera via the corresponding information transmission ring 12 and the camera transmission line 16.

As shown in FIG. 3, each TV camera 18
Includes a reference signal source 60 that supplies a reference signal voltage to a comparison circuit 62. The comparison circuit 62 compares the voltage level of the external synchronization signal P1 transmitted from the reception site 14 via the information transmission line 12 and the camera transmission line 16 with the reference signal 60, and the P1 level is equal to or less than the reference signal. By generating the pulse signal P3 when it is large, the external synchronization pulse is separated. The internal synchronization signal generation circuit 64 generates internal synchronization signals H and V synchronized with the pulse signal P3 supplied from the comparison circuit 62. The video signal generation circuit 66
A video signal synchronized with the internal synchronization signals H and V is generated and supplied to the video signal transmission line S1. The audio signal generation circuit 68 generates an audio signal together with the video signal, and the audio signal injection circuit 70 injects the audio signal into the video signal transmission line S1. The DC / video separation circuit 17 performs the camera transmission via the coupling capacitor of the signal separation circuit 17 in the same manner as the signal separation / injection circuit 21 of the current supply means in FIG. A video signal or a mixed signal of video and audio is supplied to the line 16.

As shown in FIG. 3, each TV camera 18
The ID code setting circuit 72 generates an ID code assigned to the TV camera 18 at a predetermined time during the vertical blanking cycle of the composite video signal based on the internal synchronization signals H and V, and the ID supplied from the setting circuit 72. ID code injection circuit 74 for injecting a code into video signal transmission line S1
Further included.

The video signal transmission line S by the injection circuit 74
The timing of the injection of the ID code into the control signal No. 1 is as shown in FIG.
Information signal transmission line 1 by the reception site 14 shown in FIG.
2 is different from the injection timing. The control signal is injected into the information transmission line 12 by the receiving site 14 at one or more predetermined horizontal scan lines during the vertical blanking period of the composite video signal. The ID code, on the other hand, is one of the same or separate vertical blanking periods of the composite video signal.
It is injected into the video signal transmission line S1 by the TV camera 18 at one or more predetermined different horizontal scan lines.

The ID code signal is shown in FIG. The ID code signal includes the highest or highest level of the image signal in the video signal, high level or white, the lowest level of the image signal, low level or black, and the video signal generated by the TV camera 18 shown in FIG. 10A. It is a binary code or bar code signal having two or more levels composed of an intermediate level or gray which is an intermediate level of the image signal in the signal. ID
The code may be a combination of the variable pulse width and the pulse signal level shown in FIG. 10B.

Alternatively, the ID code signal may be a pulse signal or a sine wave signal having a frequency corresponding to the ID code, and the sine wave or the pulse signal may be a pulse signal or a sine wave signal as shown in FIG.
At one or more horizontal scanning periods, preferably during a vertical blanking period.

The control signal supplied from the controller 100 shown in FIG. 6 corresponds to the ID shown in FIG.
A control code signal is generated as a shaped electronic signal similar to the code signal. However, different shaped electronic signals may be provided to the control code signal and the ID code signal. Similarly,
If the ID code is included in the control signal, it need not be the same as the ID code generated by the ID setting circuit 72 of the TV camera in FIG. Any code equivalent to the ID of each TV camera may be used instead of the same ID code.

In FIG. 3, each TV camera 18 is
A code extraction circuit 76 for extracting an ID code and a control code sent from the controller 100 shown in FIG.
The extracted ID code is compared with the ID code sent from the ID setting circuit 72, and when both codes match or correspond to each other, an ID code comparing circuit 78 for transmitting a match signal, and a code extracting circuit 76 And a decoder (decoder) 80 that decodes the control signal sent from the controller and generates a control command corresponding to the decoded control signal only when a match signal is supplied from the ID code comparator 78.

The code extraction circuit 76 shown in FIG. 8 includes a counter 84 for counting the number of horizontal synchronization pulses for each field or frame of a video signal, and a signal transmitted from the video transmission line S1 when the count of the counter 84 is a predetermined value. A gate circuit 86 connected to the output of the counter 84 for outputting the output video signal, and detecting the signal level or detecting the envelope of the signal sent from the gate circuit 88, the video transmission line S1 Level sensor 80 that reproduces and outputs a code signal extracted from the video signal sent from
And

The code comparing circuit 78 generates a match signal when the extracted code sent from the extracting circuit 76 is equal to or corresponds to the code set in the setting circuit 72, and the extracted code sent from the extracting circuit 76 When the code is not equivalent to or does not correspond to the code set in the setting circuit 72, a mismatch signal is generated to block the control command. When the control command is not combined with the ID code, the code comparison circuit is not required, and the code extracted by the extraction circuit 76 is sent directly to the decoder 80.

ID having signal waveform shown in FIG. 10C
When using codes and control signals, the level sensor circuit 8
Reference numeral 8 includes a pulse counter or a frequency counter for counting the number or frequency of the pulses sent from the gate circuit 86.

A separate control command is transmitted to the decoder 80H and the motor driver 6 shown in FIG. 3 to instruct on / off of the wiper, up / down tilting, left / right panning, tele / wide zooming, perspective focusing, aperture opening / closing, and the like. Alternatively, the motor of the TV camera 18 or other peripheral device is operated by instructing the start or stop of the transmission of the video signal. The motor driver 6 receives power supply from the charging battery 10 from the battery controller 8 via the output terminal 7 shown in FIG. The motor driver 6 also supplies current consuming peripheral devices such as a heater H6 and a fan F6 that are automatically turned on using a thermostat, and other devices such as an illuminator L6 that is automatically activated by an optical sensor or a timer. Power to peripheral devices.

A TV camera is a preprogrammed program using a microprocessor or a logic circuit.
A CPU C6 is provided to excite or activate other functions of the TV camera based on current consuming peripherals or program functions.

As is clear from the above description, the constant current is transmitted through the common transmission line for transmitting the information signal.
Power is supplied to the V-camera to supply current to the camera and associated battery, enabling random operation of the TV-camera motor and other current-consuming peripherals without disturbing the information signal by the random current drain. In addition, TV
The camera itself is powered by the associated battery when the constant current supply is cut off.

A multiplex signal composed of a video signal composed of a composite video signal and an ID code and an audio signal assigned to each TV camera is transmitted to each TV camera 1.
8 to the receiving site 14 via the camera transmission line 16 and the information transmission line 12.

As shown in FIG. 6, each receiving site 14
Is the information transmission line 12 selected by the selection circuit 30
And an interface 90 for receiving information signals sent over the interface. The interface 90 supplies the received information signal to the monitor 92 and the video cassette recorder 94.

The monitor 90 is a TV receiver that displays an image corresponding to a video signal included in the information signal transmitted from the TV camera 18 and reproduces audio according to a corresponding audio signal included in the information signal. The video cassette recorder 94 is a video cassette recorder that records and reproduces audio signals and video signals sent from the TV camera 18.

The receiving site 14 further includes a memory 96 for storing data for identifying the camera connected to the monitor 92 and an I / O for extracting an ID code from the information signal.
The D-code extraction circuit 98 and the data read from the memory 96 based on the code extracted from the information signal identify the TV camera connected to the monitor 92, and supply the identification data to the interface 90 to identify numbers or graphics. It includes a controller 100 for displaying on a monitor screen 92 along with the image generated by the video signal over the text. Similarly, numeric or graphic text is recorded by video cassette recorder 94 along with the video signal generated by TV camera 18.

The identification data may be installation location, ID number data, and text description data relating to the TV camera at that location.

The extraction circuit 98 shown in FIG. 9 includes a synchronizing signal separator 46 for separating the horizontal and vertical synchronizing signals from the composite video signal sent from the selector 30, and a horizontal or vertical composite video signal for each field or frame. A counter 84 for counting the number of scanning lines, a gate circuit 86 for outputting a composite signal sent from the TV camera for a fixed time when the count value of the counter 84 is equal to a predetermined value,
It comprises a level sensor 88 for reproducing a code signal by detecting the level or envelope of the output signal of the gate circuit 86.

The extraction identification code sent from the extraction circuit 98 is supplied by the controller 100 for reading out stored data from the memory 96. The data supplied from the memory 96 via the controller 100 is superimposed on a video signal in the interface circuit 90 to display numbers, texts or graphics on the monitor screen 92, and to determine the location or position to be imaged or monitored by the TV camera 18. Enables recognition by the operator. The controller 100 controls the superimposed display position and switches the display on / off. Such an apparatus for superimposing numeric text or graphics is disclosed in U.S. Pat. No. 4,943,864, the contents of which are incorporated herein by reference.

The controller 100 includes the controller 10
Information is transmitted and received between 0 and the selector 30. The signal sent from the selector 30 to the controller 100 includes switch-on or switch-off information for selecting the information transmission line 12. The synchronization signals H and V are sent to the controller 100 by the synchronization separator 46 to take the timing of the control command, while the controller 100 uses the external synchronization generator 31 to switch the information transmission line.
Receive the supply of the pulse P1. However, the switching time can be synchronized with the separation synchronization signals H and V.

The controller 100 supplies a selection command to the selector 30 to select an information transmission line in synchronization with an external synchronization signal. Therefore, the selection circuit 30 turns on one of the information transmission lines 12 or, in accordance with the selection command, and in synchronization with the external synchronization signal, one information transmission line 1
Switch from 2 to the other.

As a result, the mixed video and audio signals generated by the TV camera selected via the selector 30 are output to the monitor 92 for image display and audio reproduction.
And for recording video and audio signals to a video cassette recorder 94. Thus, the operator can select any of the TV cameras 18 for monitoring or recording via the controller 100 at the receiving site 14. The operator can also superimpose the numbers, text or graphics of the displayed signal on the displayed image reproduced from the video signal.

Furthermore, if the superimposed numbers, texts or graphics disturb the captured image, the operator can reposition the superimposed display or remove the superimposed display from the monitor screen.

According to the apparatus for supplying power to a TV camera via the camera transmission line shown in FIGS. 1 and 2, the TV camera is supplied with power via each corresponding transmission line and is arbitrarily combined with each other. And one, two or any number of TV cameras connected to the receiving site by a simple device and connected to a plurality of arbitrary receiving sites and monitors via a transmission line connecting the receiving site and the current supply means. Can be.

Further, since the timing of switching on or switching over the information transmission line in the selection circuit 30 is synchronized by the external synchronization signal supplied to the controller 100, the selection circuit 30 transmits the information transmission with the video signal. Switch synchronously. As a result, the reproduced image is not disturbed during or immediately after switching on or switching from one information transmission line to another.

The audio injection circuit 71 of the TV camera 18 shown in FIG. 3 may be a circuit that modulates a carrier with an audio signal and outputs a composite video signal mixed with the modulated audio. In this case, the reception site 14 shown in FIG. 6 includes an audio demodulation circuit 91 for transmitting an audio signal to the monitor 92 and the video cassette recorder 94. Further, the audio demodulation circuit may be included in the current supply means 26. FIG. 5 shows a camera transmission line 16 together with an information signal containing mixed demodulated audio.
The current supply means 26 includes the audio demodulation circuit 40 supplied from. The audio demodulation circuit employs a well-known audio demodulation IC or other standard components for outputting an audio signal from the audio out terminal 41.

Further, the audio injecting circuit 71 operates at a rate such that the time corresponding to one vertical scanning cycle of the video signal is equal to the time corresponding to one or more horizontal scanning cycles of the video signal. A circuit may be provided for compressing the time base of the signal and injecting the compressed audio signal during the vertical blanking period of the video signal.

In this case, the receiving site 14 shown in FIG.
The audio decoder 91 includes a circuit that extracts a compressed audio signal from a video signal and decompresses the extracted audio signal based on time. The audio decoding circuit 40 of the current supply unit 26 shown in FIG. 5 includes a circuit that extracts a compressed audio signal from a video signal and returns a time-based compression of the extracted audio signal.

A control signal for controlling the TV camera 18 can be supplied from a single controller to an arbitrary number of TV cameras. Otherwise, a controller may be provided in each TV camera 18 to supply a control signal from each controller to each information transmission line 12 individually. Further, a control signal may be transmitted from each reception site to each current supply unit 26 to inject the control signal into the camera transmission line 16.

As shown in FIG. 5, the current supply means 26
Includes an information signal separation / injection circuit 21 for separating an information signal from DC supplied to the camera transmission line 16.
The signal separation and injection of the signal separation / injection circuit 21 is achieved via a coupling capacitor or signal transformer that couples the different components of the information signal in two directions, and by blocking the DC component. Therefore, the control signal supplied from the receiving site 14 is supplied to the control signal input terminal 22 and injected into the camera transmission line 16 via the signal separation / injection circuit 21.

Also, instead of providing a single controller for each receiving site, two or any number of controllers 100
May be provided at the receiving site. Otherwise, a single controller may be provided at multiple receiving sites and all receiving sites may be controlled by this single controller.

[0093]

As described above, according to the present invention, the video and audio signals generated by the TV camera are
T for transmission with ID code to identify TV camera
The V-camera and its electric positioning device and other current consuming peripheral devices are supplied with power via a camera transmission line extending between the TV camera and a reception site (reception unit), and are simultaneously supplied to the TV camera via the same common transmission line. There is an effect that the external synchronization signal and the control signal can be propagated.

[Brief description of the drawings]

FIG. 1 shows T over an information transmission line according to a preferred embodiment of the present invention.
It is a block diagram of the apparatus which feeds power to a V camera.

FIG. 2 is a block diagram of a device for supplying power to a plurality of TV cameras via a corresponding information transmission line according to a preferred embodiment of the present invention;

FIG. 3 shows the T of the preferred embodiment of the device shown in FIGS. 1 and 2;
It is an electric circuit block diagram which shows a V camera device.

FIG. 4 is a block diagram of a current and battery control circuit of the preferred embodiment of the device shown in FIG.

FIG. 5 is an electric circuit block diagram showing a current supply device of a preferred embodiment of the device shown in FIGS. 1 and 2;

FIG. 6 is an electrical circuit block diagram showing a receiving site of the preferred embodiment of the device shown in FIG. 2;

FIG. 7 is a waveform diagram of a signal transmitted by the device of FIG. 6;

FIG. 8 is a block diagram of a code extracting circuit of the preferred embodiment of the TV camera shown in FIG. 3;

FIG. 9 is a block diagram of a code extraction circuit of a preferred embodiment of the receiving site shown in FIG. 6;

FIG. 10 is a waveform diagram of an ID code signal.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Rechargeable battery 12 Information transmission line 16 Camera transmission line 18 TV camera 26 Constant current supply means

Claims (31)

[Claims] An apparatus for supplying power to a TV camera via an information signal transmission line, which operates with a DC constant current and processes and outputs a multiplexed electrical information signal including a composite video signal or a digital video signal. A constant current supply unit that supplies the DC constant current to the TV camera and outputs the multiplexed electrical information signal; and a power supply that is connected to the TV camera and shuts off when the DC constant current is interrupted. A rechargeable battery for supplying power to a TV camera; and connecting the TV camera to the constant current
And a transmission line for supplying the DC constant current to the V camera and supplying the multiplexed electrical information signal to the constant current supply means. The DC constant current is required for the operation of the TV camera. The battery is substantially equal to the sum of the constant current and the constant current required to charge the rechargeable battery, and the charged battery is used to operate the TV camera when the DC constant current is turned off. A TV camera power supply device for supplying necessary power. 2. An apparatus for supplying power to a TV camera via an information signal transmission line, which operates by a DC constant current and processes and outputs a multiplexed electric information signal including a composite video signal or a digital video signal. A TV camera, a single or multiple current consuming peripherals connected to the TV camera, a rechargeable battery connected to the TV camera to power the single or multiple current consuming peripherals, A constant current supply means for supplying the DC constant current to a TV camera and outputting the multiplexed electric information signal; and connecting the TV camera to the constant current supply means to
And a transmission line for supplying the DC constant current to the V camera and supplying the multiplexed electrical information signal to the constant current supply means. The DC constant current is required for the operation of the TV camera. Substantially equal to the sum of the constant current and the constant current required to charge the rechargeable battery, the charged battery provides the power required to operate the single or multiple current consuming peripherals A TV camera power supply device, comprising: 3. The TV camera power supply device according to claim 2, wherein the single or multiple current consuming peripheral devices automatically operate via a sensor or a timer. 4. The TV camera power supply device according to claim 2, wherein the single or multiple current consuming peripheral devices operate by themselves via a microprocessor or a program circuit. 5. The TV camera power supply device according to claim 2, wherein the TV camera is automatically supplied with power by the rechargeable battery when the DC constant current is cut off. 6. A constant current supply means for generating a control signal for operating the single or multiple current consuming peripheral devices and supplying the control signal to the constant current supply means, wherein the constant current supply means comprises: The TV camera power supply device according to claim 2, wherein a control signal is transmitted to the TV camera via the transmission line. 7. An identification code signal included in the TV camera and corresponding to an identification code assigned to the TV camera, and the identification code signal is added to the multiplexed electrical information signal supplied to the transmission line. Further comprising: an identification code signal generating circuit to be injected; and receiving means for receiving, displaying, or recording a video signal included in the multiplexed electrical information signal, wherein the receiving means includes the transmission line and the current supply means. 7. The identification code signal processing unit according to claim 6, further comprising: an identification code signal processing unit that extracts the identification code signal from the video signal supplied through the control unit and supplies a signal corresponding to the extracted identification code signal to the control unit and the reception unit. TV camera power supply device. 8. The control means generates a control signal including an encoding control command with an identification code signal provided by the identification code signal processing means for operating the single or multiple current consuming peripherals. The control signal distributed to the TV camera is controlled by the encoding control command only when the identification code signal added to the encoding control command matches the identification code signal assigned to the TV camera. 8. The TV camera power supply according to claim 7, which operates a single or multiple current consuming peripherals. 9. The receiving means reads out the identification data relating to the extracted identification code signal from the memory for storing identification data of each assigned identification code, and superimposes the identification data on the video signal. The TV camera power supply device according to claim 7, further comprising a controller for the TV camera. 10. An apparatus for supplying power to a TV camera via an information signal transmission line, wherein the apparatus operates with a DC constant current and processes and outputs a multiplexed electrical information signal including a composite video signal or a digital video signal. A plurality of TV cameras, a single or multiple current consuming peripherals connected to each of the TV cameras, and a power supply connected to each of the TV cameras to power the single or multiple current consuming peripherals A rechargeable battery, a plurality of constant current supply means for supplying the DC constant current to each of the TV cameras, and outputting the multiplexed electrical information signal of each of the TV cameras, and The DC constant current is supplied to the plurality of TV cameras by being connected to the plurality of constant current supply means, and the multiplexed electric information signal is supplied to the plurality of constant current supply means. A plurality of transmission lines, a selection unit for selecting the multiplexed electrical information signal supplied by the plurality of constant current supply units, and a video signal included in the selected multiplexed electrical information signal. The DC constant current is a constant current required for each operation of the TV camera, and a constant current required for charging the rechargeable battery. Wherein the charged battery provides the power required to operate the single or multiple current consuming peripherals connected to each of the plurality of TV cameras. TV camera power supply device. 11. The TV camera power supply device according to claim 10, wherein the single or multiple current consuming peripheral devices are automatically operated via a sensor or a timer. 12. The TV camera power supply according to claim 10, wherein the single or multiple current consuming peripherals are automatically operated via a microprocessor or a program circuit. 13. The TV camera power supply device according to claim 10, wherein each of the plurality of TV cameras is automatically supplied with power by the rechargeable battery when the DC constant current is cut off. 14. The constant current supply further comprising control means for generating a control signal for operating said single or multiple current consuming peripherals and supplying said control signal to each of said constant current supply means. The TV camera power supply device according to claim 10, wherein each of the means is configured to transmit a control signal to each of the TV cameras via the transmission line. 15. The multiplexed electrical information signal included in each of the TV cameras, generating an identification code signal corresponding to an identification code assigned to each of the TV cameras, and supplied to each of the transmission lines. An identification code signal generating circuit for injecting the identification code signal into, and receiving means provided by the selection means for receiving, displaying or recording a video signal included in the multiplexed electrical information signal,
The receiving means extracts the identification code signal from the video signal supplied via the selecting means, and supplies a signal corresponding to the extracted identification code signal to the control means and the receiving means. 15. The TV camera power supply device according to claim 14, further comprising an identification code signal processing unit. 16. The control means generates a control signal including an encoding control command with an identification code signal provided by the identification code signal processing means for operating the single or multiple current consuming peripherals. The control signal distributed to the TV camera is controlled by the encoding control command only when the identification code signal added to the encoding control command matches the identification code signal assigned to the TV camera. 16. The TV camera power supply according to claim 15, activating a single or multiple current consuming peripherals. 17. The memory according to claim 17, wherein the receiving unit reads out the identification data relating to the extracted identification code signal from the memory for storing identification data of each assigned identification code, and superimposes the identification data on the video signal. 17. The TV of claim 15, including a controller for
Camera power supply. 18. An external synchronization signal generating means for generating an external synchronization signal, supplying the external synchronization signal to the plurality of TV cameras via the plurality of transmission lines, and synchronizing the plurality of TV cameras. Each includes an internal synchronization signal generation circuit synchronized by the external synchronization signal, wherein the external synchronization signal has a voltage level higher than a maximum voltage level of the video signal or lower than a minimum voltage level of the video signal. A pulse signal, wherein the receiving unit further includes a circuit for injecting the external synchronization signal into a transmission line extending from the constant current supply unit to the selection unit, and each of the current supply units is connected to the external device. A synchronization signal is transmitted to the TV camera via the transmission line, and each of the TV cameras sets a signal level of the pulse signal to a predetermined voltage. The TV camera power supply device according to claim 10, further comprising a level comparison circuit that extracts the external synchronization signal by comparing with a reference signal having a level and supplies the extracted external synchronization signal to the internal synchronization signal generation circuit. 19. The apparatus according to claim 19, wherein the selection unit includes a selection circuit for selectively turning on one or more of the plurality of transmission lines or for selectively switching one of the plurality of transmission lines to the other. The TV camera power supply device according to claim 18, wherein a power-on time or the switching time is synchronized with the external synchronization signal. 20. An external synchronization input terminal included in each of said current supply means and injecting said external synchronization signal into said plurality of transmission lines instead of said transmission line extending from said constant current supply means to said selection means. The TV camera power supply device according to claim 18, further comprising: 21. A pulse shaping circuit for generating a clipping pulse coincident with the external synchronizing pulse signal; and a synchronizing pulse from the multiplexed electric information signal supplied to the receiving means based on the clipping pulse from the selecting means. The TV camera power supply apparatus according to claim 18, further comprising: a synchronization pulse signal clipping circuit that clips a signal. 22. A plurality of pulse shaping circuits for generating a clipping pulse coincident with the external synchronization pulse signal;
A plurality of synchronization pulse signal clipping circuits adjacent to the constant current supply means for clipping the synchronization pulse signal from an output of the multiplexed electrical information signal supplied to the current supply means based on the clipping pulse. 21. The TV camera power supply device according to claim 20, comprising: 23. The TV camera further includes signal mixing means for generating a mixed signal composed of a video signal and an audio signal by injecting an audio signal into a video signal, and supplying the mixed signal to the transmission line. Item 4. The TV camera power supply device according to Item 1. 24. The TV camera further includes signal mixing means for generating a mixed signal composed of a video signal and an audio signal by injecting an audio signal into a video signal and supplying the mixed signal to the transmission line. Item 3. A TV camera power supply device according to item 2. 25. The TV camera further includes signal mixing means for generating a mixed signal composed of a video signal and an audio signal by injecting an audio signal into a video signal, and supplying the mixed signal to the transmission line. Item 11. A TV camera power supply device according to item 10. 26. The TV camera power supply apparatus according to claim 23, wherein the constant current supply unit further includes an audio signal reading unit that outputs the audio signal by reading the audio signal from the mixed signal. 27. The TV camera power supply apparatus according to claim 23, wherein the receiving unit further includes an audio signal reading unit that outputs the audio signal by reading the audio signal from the mixed signal. 28. The TV camera power supply apparatus according to claim 24, wherein the constant current supply unit further includes an audio signal reading unit that outputs the audio signal by reading the audio signal from the mixed signal. 29. The TV camera power supply apparatus according to claim 24, wherein the receiving unit further includes an audio signal reading unit that outputs the audio signal by reading the audio signal from the mixed signal. 30. The TV camera power supply apparatus according to claim 25, wherein the constant current supply unit further includes an audio signal reading unit that outputs the audio signal by reading the audio signal from the mixed signal. 31. The TV camera power supply apparatus according to claim 25, wherein the receiving unit further includes an audio signal reading unit that outputs the audio signal by reading the audio signal from the mixed signal.