Power feeding and input signal switching control system for video tape recorder combined with television receiver and camera in a body

A power feeding and input signal switching control system for use in conjunction with a video tape recording and reproducing apparatus which includes a video tape recorder, a television receiver and a camera combined together in a body. Each power source for operating each device in the apparatus is selectively fed to only devices to be operated in response to a switching action in a controller and simultaneously an input source of video and audio signals to the video tape recorder is selectively switched by the same switching action in the controller.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to power feeding and input signal switching controls 
for video tape recorders, and particularly to a control system which 
selectively controls power feeding and input signal switching according to 
each function to be selected in a video tape recording and reproducing 
system having a video tape recorder, a television receiver, and a camera 
in a single body. 
2. General Description of the prior Art 
A video tape recorder is an apparatus to record video and audio signals in 
a cassette tape and thereby reproduce the video and audio signals as 
required, and is certainly one of the most commonly used electronic 
audio/visual devices nowadays. In general, a camera may be used as one of 
the input devices for any video signals, while a monitor device or a 
television receiver have been widely used for playing original video 
and/or audio signals reproduced out of the video tape recorder. In such a 
conventional configuration as mentioned just above, it is inevitable to 
independently employ a monitor device or a television receiver, as well as 
a camera set, together with the video tape recorder in order to reproduce 
the original video and audio signals out of the video cassette tape, 
wherein each electric power source voltage to each device in the system is 
separately fed and its control to select an input signal of all the video 
and/or audio sources is not performed in one step of operation, which has 
been inconvenient for users. In consideration of such problems as stated 
above, the video tape recorder consequently has been developed, which is 
combined into a body with a television receiver and a camera. Nonetheless, 
controls for power source and input signal switching fundamentally do not 
operate in one step of manipulation. Moreover, a relatively large power 
consumption has resulted from the large size of the all-combined system. 
As a result, these almost have become a considerable obstacle in 
compacting the system into the smaller size, and furthermore have not 
given enough satisfaction to the users in the viewpoint of its functions. 
3. OBJECT OF THE INVENTION 
It is therefore the object of this invention to provide a control system 
which enables a user to simultaneously and effectively control both 
electric power feeding and input signal switching in response to the 
function to be selected in a video tape recording and reproducing 
apparatus equipped with a television receiver and a camera in one body. 
It is another object of this invention to provide a power control system 
which effectively enables a decrease in dissipation of power by only 
feeding electric power to each device in connection with the function to 
be selected in the video tape recording and reproducing apparatus. SUMMARY 
OF THE INVENTION 
The objects of the present invention are achieved with a control system for 
power feeding and input signal switching. 
The control system comprises: a control for selectively switching on/off 
each operation of said video tape recorder, said television receiver and 
said camera and providing a plurality of main power sources; power feeding 
means adapted to be coupled to the control for supplying each operating 
power source voltage to said video tape recorder, said television receiver 
and/or said camera from the main power sources selectively provided by 
said control; and signal selector responsive to the switching of said 
control for selecting the input source of video and audio signals to said 
video tape recorder.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 1 is a block diagram of the preferred embodiment of the power feeding 
and input signal switching control system in accordance with the present 
invention, in which there are included a video tape recording and 
reproducing device 10 (conventionally referred to as "VTR") adapted to be 
fed by a power source voltage V1 for respectively recording and 
reproducing both audio and video signals, a display device 20 coupled to 
the recording and reproducing device 10 and adapted to be fed by a power 
source voltage V2 for displaying the video signals on a screen, a tuner 30 
adapted to be fed by a power source voltage V3 for receiving television 
broadcasting signals in a selected channel, a camera 40 adapted to be fed 
by a power source voltage V4 for generating the video and audio signals 
out of the object selected and supplying the signals to the recording and 
reproducing device 10, a controller 50 for respectively providing a set of 
source voltages PWR and another set of selection control signals SEL in 
response to a selective switching for each function, a power separator 60 
coupled to the controller 50 for selectively providing power control 
signals CONT1, CONT2 and/or CONT3 in response to the source voltage PWR 
selected, a first switching regulator 70 connected to the power separator 
60 for feeding to both the recording and reproducing device 10 and the 
display device 20 each operating source voltage V1 and V2 by the power 
control signal CONT1, a second switching regulator 90 connected to the 
power separator 60 for feeding to the camera 40 an operating source 
voltage V4 by the power control signal CONT2, a regulator 100 connected to 
the power separator 60 for feeding to the tuner 30 an operating source 
voltage V3 by the power control signal CONT3, and a signal selector 80 
coupled to the controller 50 to enable selection as a signal input source 
for the recording and reproducing device 10 either the tuner 30, the 
camera 40 or an exterior auxiliary input jack 33, 34 in response to the 
selection control signal SEL. 
A switch 50 in the controller 50 makes up both the control signal SEL and 
the source voltage PWR at the same time, which are used to get each device 
to be selected as requested and its operating source voltage to be 
effectively fed in the combined video tape recording and reproducing 
apparatus. The source voltage PWR from the controller 50 contributes to 
produce the power control signals CONT1, CONT2 and/or CONT3, which 
respectively control the actual operations of the first switching 
regulator 70, the second switching regulator 90 and the regulator 100. By 
these controls, the regulators 70,100 and 90 succeed to feed to the 
recording and reproducing device 10, the display device 20, the tuner 30 
and the camera 40 each operating power source voltage V1, V2, V3 and VA. 
The selection control signal SEL is fed to the signal selector 80, by 
which the actual input signal to be applied to the recording and 
reproducing device 10 is selected out of a plurality of input sources such 
as a tuner, a camera, an exterior auxiliary input jack, etc. In the same 
time that one input signal source is selected to be operated, the 
recording and reproducing device 10 records and reproduces the input video 
and audio signals into/from the tape, so that the original signals may be 
played on the display device 20, or through any other means. 
FIG. 2 shows a electrical schematic diagram of the preferred embodiment of 
FIG. 1 in accordance with the present invention. In connection with FIG. 
1, the recording and reproducing device 10 consists of a conventional VTR 
circuit 11, a resistor 12, a line video-out jack 13, a line audio-out jack 
14 and an earphone jack 15. The display device 20 includes a liquid 
crystal display (LCD) device 22 and LCD driver 21 thereof which is 
connected to the VTR circuit 11. The tuner 30 includes a conventional 
tuner circuit 31 for receiving the television broadcasting signals, an 
antenna device 32, a line video-in jack 33, a line audio-in jack 34 and a 
capacitor 35. The camera 40 includes a microphone 43, a vidicon 42 and a 
control circuit 41 thereof. The controller 50 includes a battery 51, a 
regulator 52, a coupling switch 53, fuses 54 and 55, and a capacitor 56, 
the coupling switch 53 has four selective pairs of terminals 1--1', 2--2', 
3--3' and 4--4' which are operated in each pair. The power separator has a 
diode 61 of which cathode is coupled to the terminal 2 of the switch 53 
and anode is coupled to the terminal 3 of the switch 53, and another diode 
62 of which cathode is coupled to the terminal 2 of the switch 53 and 
anode is coupled to the terminal 4 of the switch 53. The first switching 
regulator 70 includes a switching regulator 71, a regulator 72, capacitors 
73, 74 and a fuse 75, the switching regulator 71 is coupled to the 
terminal 2 via the fuse 75 and the regulator 72 directly coupled to the 
same terminal 2. The signal selector 80 includes a video select switch 81 
and an audio select switch 82, both of which are operated in connection 
with the coupling switch 53 in the controller 50. The terminals 2, 3 and 4 
of the video select switch 81 are coupled to each video input or output 
port of the tuner circuit 31, the camera control circuit 41 or the line 
video-input jack 33, and in the same manner the terminals 2', 3' and 4' 
are coupled to each audio input or output port of the same. The terminals 
5 and 5' are respectively coupled to the video and audio inputs of the VTR 
circuit 11. The second switching regulator 90 includes a switching 
regulator 91, a capacitor 92 and a fuse 93, the switching regulator 91 is 
connected via the fuse 93 to the terminal 3 of the switch 53. Here, all 
capacitors 35, 56, 73, 74 and 92 are used to clear the unnecessary surge 
voltages in the control system. 
Now, the operation of the preferred embodiment of FIG. 2 will be described 
hereinafter in detail. 
When the switch 53 is set into the terminal 1--1', all the power sources to 
the control system are turned off. But, once the switch 53 is set into the 
terminal 2--2', the source voltage from the battery 51 is fed to the 
terminal 2 and at the same time to the regulator 72 and, via the fuse 75, 
the switching regulator 71. Because the terminal 2' of the switch 53 is 
turned to the ground level, the switches 81 and 82 which are operated in 
connection with the operation of the switch 53 are both set into the 
terminals 2--2', and by these switch settings both the line video-in jack 
33 and the line audio-in jack 34 are coupled to the VTR circuit 11 via the 
switches 81 and 82. The switching regulator 71 feeds a constant DC voltage 
V1 to the VTR circuit 11 and the regulator 72 feeds another constant DC 
voltage V2 to the LCD driver 21. Consequently, the VTR circuit 11 is 
operated to record the video and audio signals received via the video-in 
jack 33 and the audio-in jack 34 from the exterior system or reproduce any 
received video signals via the LCD driver 21 on the LCD device 22. Also, 
it enables transfer of the video and audio signals to any other exterior 
devices via the line video-out jack 13, the line audio-out jack 14 or the 
earphone jack 15. 
In case that the switch 53 is set into terminals 3--3', the source voltage 
from the battery 51 is fed to its terminal 3, and at the same time, fed to 
the switching regulator 91 through the fuse 93 and to the switching 
regulator 71 and the regulator 72 through the forward-biased diode 61. To 
the terminal 3' of the switch 53 is fed a DC high voltage of a constant 
value from the regulator 52. This high voltage drives the select switches 
81 and 82 to the terminals 3--3' which is respectively coupled to the 
video and audio output ports of the camera control circuit 41. Therefore, 
a constant DC voltage V4 is fed to the camera control circuit 41, and also 
the DC voltages V1 and V2 are simultaneously fed to the VTR circuit 11 and 
the LCD driver 21. Owing to these power connections, the video and audio 
signals generated in the vidicon 42 and the mike 43 are applied via the 
select switches 81 and 82 to the VTR circuit 11 to subsequently be 
recorded in the tape or reproduced on the LCD device 22. 
In the meanwhile, when the switch 53 is set into terminals 4--4', the 
source voltage from the battery 51 is fed to its terminal 4, and 
simultaneously fed to the regulator 100 and both the switching regulator 
71 and the regulator 72 via the forward-biased diode 62. At this time, the 
terminal 4' of the switch 53 is set to an open-circuited state, which 
drives the select switches 81 and 82 to the terminals 4--4' respectively 
coupled to the video and audio output ports of the tuner circuit 31. 
Therefore, another constant DC voltage V3 is fed to the tuner circuit 31, 
as well as the DC source voltages V1 and V2. By these power connections 
and input signal driving, the video and audio signals of the tuner circuit 
31 generated from the television broadcasting signals received by the 
antenna 32 in a selected channel are respectively supplied to the VTR 
circuit 11 via the select switches 81 and 82 to subsequently be recorded 
in the tape or reproduced on the LCD device 22 and/or in any other output 
devices. 
A described above, there will be achieved an efficient and easy control 
both in power feeding to each device and selecting of the signal input 
devices for the VTR system combined with the television receiver and the 
camera in a body because the manipulation of switching could be done in 
one stroke of operation. Furthermore, it will be possible to considerably 
reduce the useless power consumption in the VTR system because each power 
source voltage is fed to only the devices which are in operation.