JPS61147676A - Dewing alarm display device - Google Patents

Abstract

PURPOSE:To display immediately an alarm even just after an electric power supply is turned on and to prevent beforehand the occurrence of the troubles due to neglecting dewing and operating a VTR by flickering a light emitting display means until the electric power supply of the VTR is turned off, when the dewing condition is detected CONSTITUTION:A comparator 2 decides that the dew is stuck to a dewing sensor 1, the electric resistance value goes to be high, and the electric resistance value goes to be a prescribed value or above, and then a dewing condition is obtained, and gives an output signal (a) to a flashing circuit 3 and a control circuit 4. The flashing circuit 3, for example, uses a non-stable mono multi vibrator, etc., generates a rectangular signal (b) of 0.5sec for an on period and a rectangular signal of 0.5sec for an off period by the output signal of the comparator 2. The rectangular signal (b) is amplified at a driving circuit 5, supplied to a light emitting element 6 and the light emitting element 6 flickers. On the other hand, when an electric power supply switch 7 of VTR is turned on, the control circuit 4 detects it, and further, by detecting an input of an output signal (a) of the comparator 2, the VTR is kept to an action state for several seconds only and immediately, the electric power supply is turned off.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a VT with a video camera that integrates a video camera and a video tape recorder (hereinafter abbreviated as VTR).
The present invention relates to a dew condensation warning display device which displays a warning that dew condensation occurs when the inside of a VTR (particularly a portion of a rotary head cylinder) condenses.

Conventional technology Generally speaking, when a VTR is brought into a warm room after being used in a cold place, dew will adhere to the exterior of the VTR and the parts inside the VTR, and especially if it condenses on the outer periphery of the rotating cylinder, the magnetic tape will be damaged. There is a problem with the driving guidance. For this reason, in conventional VTRs, a sensor detects the condensation state of the rotating head cylinder, and when condensation occurs, a light emitting diode is turned on. A method of lighting up a mark has been adopted.

Problems to be Solved by the Invention In the above-mentioned VTR with a video camera, in order to warn of condensation, a small cathode ray tube is used to monitor the image taken by the video camera. It is conceivable to project and display characters and symbols. However, the electronic viewfinder does not display an image immediately after the VTR is turned on. This is for that reason. The time required for an image to appear after the power is turned on varies depending on the size of the cathode ray tube, the heating method 2, the ambient temperature, etc., but it is usually 3 to 30 T.
It takes about seconds.

On the other hand, when condensation occurs on a VTR, the frictional resistance between the rotating head cylinder and the magnetic tape inside the VTR increases, which not only seriously impedes the running of the magnetic tape and the rotation of the rotating head, but also causes damage to the electronic components. The electrical insulation between the conductors of the printed wiring board deteriorates, resulting in the problem that electronic components or conductors may be displaced from each other. For this reason, it is necessary to warn the user of the presence of condensation in some way, but it is desirable to immediately turn off the power to the VTR.

In this case, when the warning is displayed, the VTR is powered on and all electrical circuits are operating.

It is in. However, as mentioned above, the electronic viewfinder does not operate normally even after the power is turned on, so immediately after the power is turned on, text or symbols indicating condensation are displayed on the electronic viewfinder to warn you. The problem was that it was not possible.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to provide a dew condensation warning display device that immediately informs a VTR user of dew condensation.

Means for Solving the Problems In order to solve the above-mentioned problems, the condensation warning display device of the present invention detects condensation when the power of the VTR is turned on, and turns off the power of the VTR ( (including when the power is turned off automatically or manually by the user), a light-emitting display element such as a lamp or light-emitting diode to indicate the power-on state or a light-emitting diode to indicate the operating mode; The device is configured to perform a flashing operation.

Function: By configuring the present invention as described above, if condensation occurs even immediately after turning on the power to the TR, it is possible to optically display a warning to the user. This makes it possible to prevent troubles caused by operating a VTR while ignoring condensation.

Example Hereinafter, the present invention will be explained based on illustrated embodiments.

Fig. 1 is a main circuit block diagram of an embodiment of the present invention;
The figure is an external view of an example of an integrated video camera/TH embodying the present invention. In those figures, 1 is the dew condensation sensor, and since dew condensation is likely to occur in the VTFt on the mechanism part made of metal, it is usually located on the chassis of the mechanism or on the rotating head cylinder, where dew condenses most conspicuously. etc. are installed. There are many types of dew condensation sensor 1, but one that has a high electrical resistance value when dew adheres to it is often used. 2
is a comparator to which the signal from the dew condensation sensor 1 is input, and this means that when dew adheres to the dew condensation sensor 1 and its electrical resistance value becomes high, if the electrical resistance value exceeds a predetermined value, It is determined that there is dew condensation, and an output signal a is given to the next stage flushing circuit 3 and control circuit 4.

Various types of flushing circuits can be used for the flushing circuit 3. For example, an astable monomultiply resistor is used, and depending on the output signal of the comparator 2, the on period is 0.6 seconds and the off period is 0.6 seconds. It generates a 5 second rectangular wave signal. The rectangular wave signal is supplied to a drive circuit 6 and amplified, and then sent to a light-emitting display means, for example, a light-emitting element 6 such as a light-emitting diode that indicates the power-on state of the video camera integrated T/TR 13 illustrated in FIG. Supplied. As a result, the light emitting elements flash on and off for 0.5 seconds at 1 second intervals.

On the other hand, the control circuit 4 controls the entire video camera integrated VTR 13, such as a microcomputer, and detects when the power source of the VTR is turned on. By detecting the input of output signal a of 2, VT
The operation is to leave R in operation for only a few seconds and then immediately turn off the power. In addition, when there is no condensation, the drive circuit 5 is set so that the drive circuit 6 supplies the light emitting element 6 with a constant DC voltage and an AC voltage with a relatively high frequency that is not visible due to flashing. Control. Therefore, in this case, the light emitting element 6 does not visibly blink, but emits light at a predetermined brightness.

Furthermore, the control circuit 4 controls the output signal a of the comparator 2.
is being input (that is, in a dew condensation state), the character generator 8 is controlled to generate a character signal (or a symbol that indicates dew), for example, to display "DKW", which means dew in English, on the cathode ray tube screen. signal) C is generated. This character signal C is mixed with the video signal d output from the video camera section 11 in the mixer 9, and is supplied to the cathode ray tube type electronic viewfinder 10. A warning about condensation is displayed. In this case, immediately after the '/TH is powered on, the electronic viewfinder 10 will not operate normally as described above, so the jDIcWJ warning will not be displayed, and the warning will not be displayed due to the 7 lashing of the light emitting element 6. is done first. And electronic viewfinder 1
When the heater of 0 is warmed up and starts to operate normally, the above-mentioned "
The characters DEWJ are displayed on the electronic viewfinder 10. Of course, even if the VTR has just been turned on, if the cathode ray tube heater has not completely cooled down, such as when it has not been a long time since the previous use, the
Needless to say, it is possible to display a warning using the characters DEWJ.

In fact, if the power is turned off for a longer period of time than it takes for the heater to warm up, it will be found that condensation will form immediately due to the flashing operation of the light emitting element 6, and the electronic viewfinder will 10, the condensation warning display will also appear on the electronic viewfinder 10 before the power is turned off.

Note that, as shown in this embodiment, if the output signal e of the mixer 9 is made to be able to be taken out from the external output terminal 12 to the outside of the VTR main body as a video signal output, the external output terminal 12
By connecting a monitor television receiver to
The warning characters jDEWJ can also be displayed on the video screen. However, in this case, it is effective if the monitor television receiver is powered on in advance so that it can display images at any time.

Furthermore, in this embodiment, a light emitting element such as a light emitting diode (or lamp) that indicates the power-on state of a VTR is also used as the light emitting element 6 that displays a dew condensation warning through a flashing operation, but this example is not limited to this example. Other VTR
A light-emitting element (or lamp) such as a light-emitting diode can also be used to indicate the operation mode. In this case, two or more light emitting elements may be subjected to seven lasing operations at the same time.

Effects of the Invention As is clear from the above description, the condensation warning display device of the present invention causes the light emitting display means to blink until the power of the VTR is turned off when a condensation condition is detected. Even if the power to the VTR is turned on, if there is condensation, a warning message will be displayed immediately, thereby preventing troubles caused by ignoring condensation and operating the VTR. It is something. Therefore, the present invention is particularly useful when used in conjunction with a video camera integrated VTR equipped with an electronic viewfinder in which characters or symbols representing dew condensation are projected on the video screen of the electronic viewfinder. It is. Also,
As described in the previous embodiment, the light-emitting element that displays the condensation state can also be used as the light-emitting element that displays the power-on state of the video tape recorder or the light-emitting element that displays the operation mode, resulting in a relatively simple configuration. In addition, an excellent effect can be obtained in that it can be realized at low cost.

[Brief explanation of the drawing]

Fig. 1 is a main circuit block diagram of an embodiment of the present invention;
The figure is an external view of an example of a video camera integrated video tape recorder embodying the present invention. 1... Condensation sensor, 2... Comparator, 3... Flushing circuit, 4...
・Control circuit, 6..., drive circuit, 6...
- Light emitting element, 7...Power switch. 8...Character generator, 9...
...Mixer, 10...Electronic viewfinder, 12...External output terminal.

Claims (3)

[Claims] (1) A video tape recorder with a video camera that integrally combines a video camera that converts a subject into a video signal using an imaging medium and a video tape recorder that records the video signal obtained by the video camera on a magnetic tape, The video tape recorder includes a dew condensation detection means for detecting a dew condensation state inside the video tape recorder, and a dew condensation warning display means for blinking a light emitting display means until the video tape recorder is powered off in response to the dew condensation detection means. Condensation warning display device. (2) The dew condensation warning display means includes a warning character display means for displaying characters or symbols representing the condensation state on the video screen of the electronic viewfinder, and a signal processing means for mixing the signal representing the characters or symbols with the video signal output. Claim No. (1) is characterized by comprising:
Condensation warning display device as described in section. (3) A dew condensation warning display as set forth in claim (1), wherein the light-emitting display means serves as either a light-emitting element that displays a power-on state or a light-emitting element that displays an operation mode. Device.