Single button VCR operation system

A VCR operation system, wherein it is possible to perform a backspace function by operation of a switch button during record or playback. During record or playback of a VCR with a rotary head, if a user wants to play back scenes which he has just watched, he only has to push the switch button, and the tape is rewound for a predetermined period of time, or while the switch button is being pushed. Then the tape is automatically set to a playback mode so that the user can watch the last recorded or played back scenes. In response to another operation of said switching button, the VCR is set to a record or playback mode again. It is also possible to arrange such that the tape position at the time of switching button is memorized and the VCR is set to the record or playback mode again when the tape reaches the memorized position during playback.

BACKGROUND OF THE INVENTION 
The present invention relates to a video cassette tape recording driving 
system. 
According to conventional VCRs, when a user wants to play back again 
recorded scenes that he has just monitored during recording, he must stop 
the recording tape once for unloading, rewind the tape to a desired tape 
position, stop the tape again, and thereafter load the tape to playback. 
He then has to wait until the tape begins to start. These operations 
should be repeated for adjusting, and it is not easy to play back the 
desired recorded scenes in a moment during the recording and thereafter 
switch to a recording mode again. It causes a time loss and is complex in 
operation. 
SUMMARY OF THE INVENTION 
According to the present invention, when a user wants to watch again 
recorded scenes that he has just watched during recording or to confirm 
the recording of said scenes, it is possible to automatically rewind the 
tape for a predetermined period of time by pushing a button momentarily so 
as to play back said scenes, and to switch to the recording mode by 
pushing said button once again during said playback. 
It is an object of the present invention to enable anybody to perform easly 
and surely a backspace function, i.e., means for rewinding the tape of a 
VCR and thereafter playing back recorded scenes automatically and means 
for returning the VCR to a recording mode, by operating a button during 
recording. 
The above and other objects, features and advantages of the present 
invention will become more apparent from the following description when 
taken in conjunction with the accompanying drawings in which preferred 
embodiments of the present invention are shown by way of illustrative 
example.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The detailed description of the preferred embodiments according to the 
present invention will be now described with reference to the accompanying 
drawings. 
Referring to FIG. 1, reference numeral 1 denotes a clock oscillator having 
a cycle of about 0.8 second made of a multivibrator etc. Reference numeral 
2 denotes a decimal counter for controlling the operation which will be 
explained later, and in this preferred embodiment, IC 4017 which is on the 
market is used, reference symbol C denotes a clock terminal, reference 
symbol R denotes a reset terminal, and reference symbol CE denotes a clock 
enable terminal. In the decimal counter 2, an output terminal Q1 is set to 
H level in response to a number count of 1, and an output terminal Q2 is 
set to H level in response to a number count of 2. 
Reference symbols FF-1 and FF-2 denote an R-S type flip-flop. In this R-S 
type flip-flop FF-1 and FF-2, reference symbol S denotes a set terminal 
and reference symbols R1 and R2 denote reset terminals, but the terminal 
having a bar over the each symbol indicates response to negative logic. 
Reference symbol FF-3 denotes binary type flip-flop. Reference symbol G1 
denotes a NAND gate. Reference symbols G2 and G4 denote AND gates. 
Reference symbol G3 denotes an invertor. Reference numerals 3-6 denote 
transistors. 
Collectors and emitters of the transistors 3-6 are connected respectively 
to each terminal of a rewinding key (REW), a stop key (STOP), a playback 
key (PLAY) and a recording key (REC) of a VCR (not shown in FIG. 1). 
In the VCR, when the recording key (REC) is pushed, a specified TV program 
is recorded by the VCR. When a user wants to see again and to confirm the 
recorded TV program, a momentary type switch SW1 is set to ON, and as a 
result, the flip-flop FF-1, the flip-flop FF-2 and the flip-flop FF3 which 
are reset by a reset circuit comprising a resistance R1 and a capacitor C1 
when a power supply is set to ON, are operated as follows. 
When the flip-flop FF-1 is set by pushing the switch SW1, output Q from the 
flip-flop FF-1 is changed from H level to L level. Accordingly, reset of 
the counter 2 is released, and the counter 2 starts to count clock pulses 
from the clock oscillator 1. At the same time, the binary type flip-flop 
FF-3 is changed to a set condition by changing from L level to H level an 
output Q from the flip-flop FF-1 (this operation will be described later). 
FIG. 2 shows a timing chart corresponding with the clock pulse. The 
flip-flop FF-1 is set to ON by turning on the switch SW1, and the counter 
2 counts "1" by counting a clock pulse P2 by the counter 2. As a result, 
an output Q1 from the counter 2 is changed to H level. 
In FIG. 1, the output Q1 sets the transistor 4 to ON through the resistance 
R4. Accordingly, the recording operation is released as the stop key 
(STOP) of the VCR is pushed. 
In FIG. 2, when the counter 2 counts a clock pulse P3, the counting amount 
becomes "2". The output Q2 (not connected) from the counter 2 is changed 
to H level, and the output Q1 is returned to L level. As a result, a 
stopping operaton of the VCR is released. When the counter 2 counts a 
clock pulse P4, and "3" is counted by the counter 2, the output Q3 from 
the counter 2 is changed to H level. The output Q3 from the counter 2 sets 
the transistor 5 to ON through the AND gate kG-2, because the binary type 
flip-flop FF-3 has already been changed to the set condition, the AND gate 
G-4 is passive, and the AND gate G-2 is active through the invertor G-3. 
As a result, the VCR is changed to the play back mode. However, the 
counter 2 counts a clock pulse P5 and a clock pulse P6 during controlling 
the mechanism section by the VCR for playing back a part of the recorded 
TV program, so that "5" is counted by the counter 2. Accordingly, the 
output Q5 from the counter 2 sets the R-S type flip-flop FF-2 through the 
NAND gate G-1 (activated by the output from flip-flop FF-3). The 
transistor 3 is set to ON by the output from the R-S type flip-flop FF-2, 
and the VCR is set to a rewinding operation. 
Because the VCR has already been set previously to a playback mode, the VCR 
is set to the review mode which rewinds a tape simultaneously with playing 
back the recorded TV program. The review mode continues during counting of 
clock pulses P7, P8, P9 and P10 by the counter 2; for example, in this 
embodiment, it continues for about three seconds. 
When the review mode of three seconds passes, the output Q9 from the 
counter 2 is set to H level, this output resets the flip-flop FF-2, the 
review operation is released and the VCR is set to the playback mode. At 
the same time the output Q9 resets the flip-flop Ff-1 and also the counter 
2 is reset by the output from the flip-flop FF-1. Accordingly, in this 
condition, only the flip-flop FF-3 is in the set condition, and the VCR is 
continuing the playback mode as the operation thereof. 
In the playback mode, an operator finishes watching a picture which is 
played back. The operator pushes the switch SW 1 again in order to start 
the recording operation again. As a result, as above, the flip-flop FF-1 
is set, and the counter 2 is activated to the counting condition. However, 
in this operation, the binary type flip-flop FF-3 is changed to the reset 
condition by the output from the flip-flop FF-1. Accordingly, the NAND 
gate G-1 and the AND gate G-2 become inactive, and the AND gate G-4 
becomes active through the invertor G-3 by setting the output from the 
flip-flop FF-3 to L level. 
In the above condition, the counter 2 counts a clock pulse from the clock 
oscillator 1, and the counter counts "1" by clock pule P31 shown in FIG. 
2, then the VCR is stopped, as above, the counter 2 counts "3" by the 
clock pulse P32, and sets the transistor 6 to ON through the AND gate G-4. 
As a result, the VCR is set to the recording condition. 
In the VCR operation that follows (not shown in the drawings), as above, 
the NAND gate G-1 becomes passive by counting amount of "5", and 
accordingly, this operation is ignored. Furthermore, when the count 
reaches "9", the flip-flop FF-1 and the flip-flop FF-2 are reset, and as a 
result, the following recording operation that follows continues as an 
operation of the VCR itself. 
The second embodiment will be explained with reference to FIG. 3. In the 
first embodiment (FIG. 1), when the switch SW1 is pushed, a rewinding of 
the tape is rewound for about three seconds. Namely, a rewinding time is 
peset. In the second embodiment, it is possible to rewind the tape 
continuously during pushing of the switch SW1. Thus, this embodiment can 
change the rewinding time as occasion demands of a user. 
When a user wants to play back the tape in the VCR in the recording 
condition, the switch SW 1 must be continued to be pushed. The flip-flop 
FF-1 (a reset terminal R3 is supplemented in the flip-flop FF-1 in FIG. 3 
compared with flip-flop FF-1 in FIG. 1) is set, and the reset condition of 
the counter 2 is released as in the first embodiment. At this time, the 
terminal 1 of the AND gate G-5 is set to L level by the output of the 
flip-flop FF-1, the terminal 2 of the AND gate 5 is kept in the L level 
until the capacitor C3 is charged, and as a result, the output 3 from the 
AND gate G-5 is set to L level, and the counter 2 counts a clock pulse. 
When the counter 2 counts "1", the output Q1 is set to H level and the VCR 
is stopped through the transistor 4. On the other hand, after the VCR is 
stopped as above, when the capacitor C is charged by continuing to push 
the switch SW1 through the inverter G-6 and the resistance R8, the tape in 
the VCR is rewound through the transistor 3. At the same time, an input 
terminal 2 of the AND gate G-5 is set from L level to H level, and as a 
result, the counter 2 counts "2", and the output Q2 in the H level stops 
the operation. 
In FIG. 3, the clock pulse width is set by a time constant of R8.times.C3. 
At this time, even if the output Q2 is at the H level, there is no 
operation on this stage, because the flip-flop 3 is changed to the set 
condition and the AND gate is passive. When a specific quantity of the 
tape is rewound, the switch SW1 is set to OFF, the output from the 
inverter G-6 is set to L level, and the terminal 2 of the AND gate G-5 
returns to L level. When the counter 2 counts "3" by counting the next 
clock pulse, the output Q3 becomes L level, and the VCR is switched to the 
playback mode through the transistor 5. Alternatively, it is also possible 
to carry out a review operation which rewinds the tape after changing to 
the playback mode as in the first embodiment. 
When the next clock pulse is input, and the counter 2 counts "4", and also 
the output Q4 is changed to the H level, and the flip-flop FF-1 and the 
counter 2 are reset by te output Q4. On the other hand, the VCR continues 
playback mode as the operation thereof. 
When a user wants to start the recording again, the switch SW1 is pushed 
again, and as a result, the flip-flop FF-1 is set, and the counter 2 
starts to count clock pulse. When the counter 2 counts "1", the counter 
stops the VCR. When the counter 2 counts "2", the counter 2 switches the 
VCR to the recording operation through the AND gate G-4, and the flip-flop 
FF-1 and counter 2 are reset through a time constant of R7.times.C2. 
Thereafter, the VCR continues the recording operation by itself. 
The third embodiment, operated by a microcomputer, will be described 
referring to FIG. 4. In FIG. 4, reference symbol SW-1 denotes a one touch 
type switch. Reference symbol CPU denotes a microprocessor 
(microcomputer). Reference numeral 41 denotes an operating switch section 
for rewinding playback, recording, etc. Reference numeral 42 denotes a 
mechanism section of the VCR. The mechanism section 42 has a rotation 
sensor for detecing a pulse generated in accordance with rotation of a 
reel stand in order to read a position of a tape (not shown in FIG. 4) in 
the VCR. Reference numberal 43 denotes a RAM (random access memory) for 
memorizing the pulse number to store the tape position. 
Referenc numeral 44 denotes a display section which dislays an operation 
mode of the VCR, a running position (running quantity) of the tape, etc. 
First, the VCR has been set previously to the recording mode as above. The 
pulse generated corresponding with running of the tape in the VCR is 
detected by the rotation sensor, and the running position (running 
quantity) of the tape is memorized in a specified address of the RAM as a 
pulse count. When the switch SW-1 is pushed in order to playback recorded 
contents, the tape is rewound for three seconds, e.g., by a timer as in 
the first embodiment. Alternatively, while the switch SW-1 is pushed, the 
push is detected by CPU 40 and the tape is rewound during pushings as in 
the second embodiment. 
While the tape is rewound, the pulse count is subtracted from the tape 
position, but when the tape is changed from the rewinding operation to the 
playback operation, the pulse count is added to the tape position. 
When the tape reaches the tape position where the switch SW-1 is pushed, 
this position is compared with the position memorized in the RAM 43. When 
this position coincides with the memorized position, the VCR is switched 
to the recording operation automatically. Alternatively, when the pulse 
number while the tape is rewound is memorized, and the pulse number 
coincides with the pulse count after switching to the playback operation, 
the VCR can also be switched to the recording condition. 
In both the above operations, when the tape reaches the tape position where 
the switch is pushed, the VCR is set to be switched automatically to the 
recording operation. Accordingly, the operation for switching to the 
recording operation becomes easy as shown in the first and second 
embodiments. 
As the above explanation, when a user wants to see again or to confirm the 
recorded part in the recording condition of the VCR using a revolving type 
head, the tape can be rewound and played back for the fixed time set 
previously only by operation of pushing the switch. This operation to see 
the recorded part can be repeated many times. When the switch is pushed 
again, the recording operation can be continued, namely, this operation 
can be operated by ON/OFF operation of only one switch. Thus, this 
invention increases the practical effect of such kinds of device. 
Although certain preferred embodiments have been shown and described, it 
should be understood that any changes and modifications may be made 
therein without departing from the scope of the invention.