JPH0546024B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a video system, and more particularly to a video system that aims to reduce the size and weight of a video recorder and is mainly used for photographing.

Conventional portable video systems have been called portable video tape recorders (hereinafter referred to as "portable video tape recorders"), which have a recording and playback function and even have a built-in RF converter that converts the playback video signal into an RF signal for playback on a home TV.
The VTR itself consists of a video camera (referred to as a VTR) and a video camera, and has the problem of lacking portability and maneuverability due to the volume and weight of the VTR itself.

The present invention solves the drawbacks of the conventional example described above by configuring a video recorder to primarily have a recording function, and at the time of playback, the video recorder is used in combination with another unit having a playback function (hereinafter referred to as a playback unit). In other words, it is an object of the present invention to provide a video system that achieves reduction in the size and weight of equipment used during photographing and improvement in the operability of the system as a whole.

Figure 1 shows the conventional video camera 1 and TVR during shooting.
2 is used by connecting the two with a cable 3.

Furthermore, this VTR 2 is configured so that when it is set to play mode during playback, the playback signal can be played back on a television using a built-in RF converter or the like.

2a and 2b show a video system mainly composed of a video camera 4, a VTR 5, and a playback unit 6 according to an embodiment of the present invention.

The VTR5 is mainly configured to have a recording function, a playback function, and a power supply circuit (AC power supply).
and system control functions are built into the playback unit 6.

FIG. 2a is a perspective view showing a state in which the VTR 5 and camera 4 are combined, and 7 shows an electronic view finder.

FIG. 2b is a connection diagram during playback, and the VTR 5 and playback unit 6 may be connected by cable or mechanically through a connector such as a hot shoe.

FIG. 3 shows a block diagram of the circuit of each unit according to the present invention. In the camera section 4, a video signal is obtained by an optical system 8, an image sensor 9, and a camera signal processing circuit 11, and is outputted to a terminal b. Also the second
The audio signal obtained from the microphone 4-M in FIG. 4A is outputted to the terminal a via the preamplifier 10. The audio signal and video signal obtained from the camera section in this way are transmitted to the audio recording amplifier 34 and the video signal recording circuit 1, respectively.
The information is recorded on the magnetic tape T via the audio head 20 and the rotary magnetic head (not shown) provided on the cylindrical tape guide (hereinafter referred to as drum) 18. At this time, the recording servo circuit 13 controls the rotation of the drum motor 16 in phase synchronization with the synchronization signal of the recorded video signal, and the capstan motor 17 is controlled at a constant speed to record the image on the tape wound diagonally around the drum 18. The signals are sequentially formed into tracks by a rotating video head, and the audio signals are recorded on one end of the tape. At the same time, a control track is formed at the other end of the tape corresponding to the frame frequency of the synchronizing signal in the video signal.

Detection heads 22 and 23 detect the rotational speed and rotational phase of the rotary head and capstan, respectively, and during recording, feed back to the recording servo circuit 13 via switches S5 and S7. 14,
Reference numeral 15 indicates a drive circuit for a drum motor and a capstan motor, respectively, and during recording, a servo error signal and the like are supplied from the recording servo circuit. Reference numeral 27 is a system control circuit that controls the reel motor 24, loading motor 37, pinch roller solenoid 25, shutter-off solenoid 26, etc. in response to the operation of the VTR operating section 28, and controls the conventional VTR.
Recording of video signals from cameras etc., known as
This is a circuit block that sets modes for fast forwarding, fast rewinding, loading, and unloading.

By combining the camera 4 and VTR 5 during recording, the above recording and playback mode switching switches S ₁ , S ₂ , S ₃
... _S8 is designed to switch to the input side as shown in Figure 3. That is, in FIG. 4, the changeover switch 35 incorporates the mode changeover switches _S1 to _S8 , and when pressed by the protrusion 4-b provided on the camera, the changeover switch 35 switches the mode changeover switches _S1 to _S8 as described above. It is configured to switch as desired. With this configuration, recording/reproducing mode switching, which requires a large number of circuits, can be easily and reliably performed, and the recording mode can be set by connecting the camera, so there is no failure.

Furthermore, these playback mode switches S ₁ to _{S 8} can be switched to the opposite side from the input position shown in FIG. are connected in circuit via connection terminals C to J.

On the playback unit 6 side, 29 is an audio playback circuit;
30 is a video signal reproducing circuit, 31 is an RF converter, 3
Reference numeral 2 indicates a reproduction servo circuit, and reference numeral 33 indicates a system control section.

Next, the functions and operations of the VTR 5 during shooting will be explained with reference to FIG.

Figure 6 shows the system control section 27 in Figure 3.
FIG. 2 is a circuit connection diagram showing the configuration of a loading motor control circuit in the embodiment. 38 is a switch that is turned on when tape loading is completed, 39 is a switch that is turned on when tape unloading is completed, and 42 is a switch that is linked to switch 39 and is opened when the switch is closed. Also, 36 is as shown in Figure 2.
A power switch installed on the VTR6 and operated from the outside that allows you to switch off, standby 1 and standby 2.
It has three positions. This power switch 36 is composed of interlocking switches 36' and 36'' that are configured to sequentially switch contacts a, b, and c. When a cassette is loaded into the VTR 6 and the power switch 36 is set to standby 1, the interlocking switches 36' and 36'' are switched on. Each is connected to contact b, and when set to standby 2, each is connected to contact c. A switch 41 is opened only when the switch 36 is in contact with the a contact, that is, in the OFF position, and is closed at all other times. The three switches 36, 38, 39 connected in parallel
are connected to the + side of the power supply on one side and grounded on the other side via resistors R ₁ , R ₂ and R ₃ , and a switch is connected to the connection point with each resistor R ₁ , R ₂ and R ₃ .・
A high signal is obtained when the switch is on, and a low signal is obtained when the switch is off. IV ₁ , IV ₂ and
IV ₃ turns on each switch 38, 36, 39, respectively.
The inverter NA ₁ is a Nant gate designed to receive the signal obtained at the output of the inverter IV ₁ and the connection point between the power switch 36 and the resistor R ₂ . ₂
are NAND gates configured to receive the outputs of inverters IV ₂ and IV ₃ ; IV ₄ and IV ₅ are inverters for inverting the outputs of the NAND gates NA ₁ and NA ₂ , _respectively ; , IV ₅
The output of is connected to npn switching via resistors R ₄ and R ₅ .
It is designed to be attached to each base of transistors TR ₁ and TR ₂ . Here, the collector side of transistor TR ₁ is connected to pnp switching via resistor R ₆ .
It is connected to the base of the transistor TR ₃ , and its emitter side is connected to the base of an npn switching transistor TR ₄ located diagonally to the transistor TR ₃ , and connected to its own base via a resistor R ₇ . It is connected. On the other hand, transistor
The collector side of TR ₂ is connected via a resistor R ₈ to the base of a pnp switching transistor TR ₅ ,
Further, its emitter side is connected to the base of an npn switching transistor _TR6 located diagonally to the transistor _TR5 , and is also connected to its own base via a resistor _R9 . Note that the emitter sides and bases of transistors TR ₃ and TR ₅ (the bases are connected to the power supply path A through resistors R ₁₀ and R ₁₁ , respectively)
Also, the emitter sides and bases of transistors TR ₄ and TR ₆ (the bases are connected to resistors R ₁₂ and
_R13 ), and the loading motor 37 is connected to transistors _TR5 and
Collector connection point of TR ₄ and transistors TR ₃ , TR ₆
It is inserted and connected between the collector connection point of the

In such a configuration, when the tape unloading is completed and the power switch 36 is turned on by standby operation, the NAND gate will be turned off.
The output of NA ₂ is high, therefore the output of inverter IV ₅ remains low, the output of NAND gate NA ₁ is low, therefore the output of inverter IV ₄ is high, which causes transistor TR ₁ to conduct. Therefore, the transistors TR ₃ and TR ₄ become conductive, and a current flows through the loading motor 37 in the direction of the arrow X, causing the motor 37 to rotate in the normal direction, thereby performing a table drawing operation. In other words, as shown in Figure 5a, the pull-out pins 43 and 4 located inside the tape inside the cassette
4, 46 and the pinch roller 45 are moved in conjunction with the loading ring 47 driven by the loading motor 37, as shown in FIG. Pull out the tape until it does. When the tape loading completion detection switch 38 is turned on as described above at the loading completion position, the output of the NAND gate NA ₁ becomes high, and therefore the output of the inverter IV ₄ becomes low, so that the transistor TR ₁ becomes non-conductive, and thus both transistors TR ₃ and TR ₄ become non-conductive, causing the motor 37 to stop. On the other hand, when the power switch 36 is turned off in this tape loading state at the end of shooting, the 41
will be developed. At this time, since the tape unloading completion detection switch 39 is off, the output of the NAND gate _NA1 is high, and therefore,
The output of inverter IV ₄ remains low and the output of NAND gate NA ₂ is low, therefore, inverter IV ₅
output goes high, which causes the transistor
Transistors TR ₅ and TR ₆ for TR ₂ to conduct
conducts, current flows through the loading motor 37 in the direction of arrow Y, and the motor 37 rotates in reverse. Then, when the tape unloading completion detection switch 39 is turned on at the tape unloading completion position, the output of the NAND gate NA ₂ is high, and therefore the inverter IV ₅
Since the output of is low, transistor TR ₂ is non-conducting, and therefore transistors TR ₅ and TR ₆
The motor 37 comes to stop because it becomes non-conductive. Thus, loading motor 37
By rotating in the forward direction, the tape T is loaded onto the guide drum 18, and by rotating in the reverse direction, the tape T is unloaded into the cassette. At this time, in the standby 1 state, no power is connected to power path B that supplies power to other circuit systems such as the signal processing system and servo system, and when the camera trigger TG is closed, power is supplied starting from power path A. is injected. For this reason, in consideration of the start-up of circuit systems such as drums and capstans, the drive circuit 49 drives the pinch roller crimping solenoid 25 after the camera trigger TG is operated and turned ON.
The delay circuit 48 is set by the switch 3 to set the time until the
It is set slightly longer in conjunction with 6. This mode is intended to reduce power consumption when the shooting interval is relatively long, although the tape rise time after release is slightly delayed. Standby 2 mode is set by interlocking switches 36' and 3 for other circuit systems.
6" is set to C, the power is turned on and the rotation system is started, so the pinch roller is linked to the switch 36, contrary to the above, so that it presses against the capstan instantly after the camera trigger is turned on. Therefore, the delay time of the delay circuit 48 is set to be short.

Next, the operation during playback will be explained.

During playback, the camera is separated from the VTR and connected to the playback unit 6. At the time of connection, the system control block 27 is electrically or mechanically switched to the system control block on the playback unit 6 side. In other words, in this case, all operating functions are controlled by the playback unit. This means that the user can concentrate on operating the playback unit without hesitation.

Furthermore, as described above, the recording/reproducing mode setting switches _S1 to _S7 are located on the opposite side from the recording side shown in FIG. Therefore, the video signal and the audio signal recorded on the tape are transmitted to the RF via the video signal reproducing circuit 30 and the audio reproducing circuit 29 via S ₄ and S ₅ , respectively.
The converter 31 converts the signals into TV and RF signals, and reproduces them on the TV. A reproducing servo circuit 32 is provided on the reproducing unit side and performs reproducing tracking servo by receiving the TACH pulse obtained from S ₅ , S ₆ , and S ₇ , the reproduced CTL signal, the capstan FG output, etc.

As described above, according to the present invention, a video recorder is configured to be as small as possible so as to have the minimum necessary functions mainly for recording, and when playing back, the video recorder can be simply connected to another unit having a playback function. Since the recording associated with the operation of the first operation part is disabled, the user can concentrate on operating the second operation part on the playback unit side when trying to playback, and prevents the user from inadvertently using the first operation part. It is possible to prevent erroneous operations caused by manual operations, and has an extremely excellent effect in terms of operability and portability of the entire system.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a conventional video shooting system, and FIGS. 2a and 2b show an embodiment of the video signal recording and reproducing system of the present invention, which is composed of a video camera 4, a VTR 5, and a reproducing unit 6. 3 is a block diagram showing the circuit of each unit according to the present invention, FIG. 4 is an explanatory diagram illustrating switching of switches S ₁ to _{S 8} in FIG. 3, and FIGS.
b is an explanatory diagram showing the tape unloading state and loading state, respectively, and FIG. 6 is a circuit connection diagram showing the configuration of the loading motor control circuit. 4...Video camera, 5...VTR, 6...Playback unit, _S1 to _S8 ...Recording/playback mode switch, 35...Switch switch with built-in switches _S1 to _S8 , TG...Camera trigger , 48...Delay circuit, 36...Power switch consisting of interlocking switches 36', 36''.

Claims (1)

[Scope of Claims] 1. A video camera unit capable of capturing an image of a subject; a recording/reproducing head; a recording circuit capable of inputting a video signal from the video camera unit; a video recorder section including a recording/playback switch for connecting a recording circuit and the head; and a first operating section capable of recording and instructing a video signal from the video camera section; a playback unit section including a playback circuit connected to the head via the switch and a second operation section capable of instructing playback, the video recorder section being connected to the video camera section. when the recording circuit and the head are connected by the changeover switch, the recording command is enabled by the first operation section, and the video recorder section is connected to the playback unit. When the playback circuit and the head are connected to each other by the changeover switch, the recording operation by the first operation part is prohibited, and the recording operation by the second operation part is prohibited. A video signal recording and reproducing system characterized in that a reproduction command is possible.