JPH07322122A - Power supply controller for video camera accessory - Google Patents

Abstract

PURPOSE:To provide an easy-to-handle power supply controller which can omit a conventional adaptor for reduction of cost and also can shorten the video photographing time by supplying the battery power to a video camera accessory connected to a hot shoe of a battery set from the hot shoe in response to the current flowing to a video camera circuit. CONSTITUTION:A hot shoe 58 is attached to a battery set 52 which can freely attached to and detached from a video camera 51 and supplies the power to a video camera circuit. Thus a video camera accessory 53 is attached to the camera 51 via the shoe 58. When a current flows to the video camera circuit from the set 52, the power is supplied to the accessory 53 from the set 52 via the shoe 58 in response to the current flowing to the video camera circuit. Furthermore a signal supply circuit detects the current flowing to the video camera circuit from the set 52 and sends an ON/OFF signal which is outputted according to a power supply or power supply stop state to the accessory 53 via the shoe 58.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply control device for a video camera, such as a monitor TV, a sound collecting microphone, and a video light, which is used when a video camera shoots.

[0002]

2. Description of the Related Art There are various types of video cameras, for example, a built-in power source with a battery in the camera body or a detachable battery set without a power source in the camera body. There is a type that is mounted and operates on this battery power. There is also a structure in which accessories such as a monitor TV, a sound collecting microphone, and a video light can be attached to the camera body for use.

Some of these video cameras do not have not only a power supply but also a mounting portion for the above-mentioned accessory. When such a video camera is attached with the above-mentioned accessory for photographing, a battery set is used. Along with this, an adapter is attached, and the accessory is connected to the hot shoe provided for this adapter so that both the video camera and the accessory can be operated by battery power.

[0004]

A video camera which does not have a battery and a connecting part of accessories has to be equipped with the above-mentioned accessories by using an adapter as described above, which is costly. It is also inconvenient to carry.

Further, for example, when a monitor TV as an accessory is connected to an adapter for video recording, the power switch of the monitor TV is manually turned on before moving to shooting.
At the end of shooting, you have to turn it off again manually,
Whenever shooting and cancellation of shooting are repeated, the power switch is turned on and off, which makes the operation troublesome. On the other hand, it is not preferable to operate the monitor television until the shooting operation is completed regardless of whether the shooting and the shooting are repeated, because the power consumption of the battery increases and it becomes extremely uneconomical.

In view of the above-mentioned situation, the present invention is a power supply control for a video camera accessory, in which a video camera accessory is connected to a battery set and the accessory can be operated by a battery power source in accordance with the power supply to the video camera. The purpose is to develop the device.

[0007]

In order to achieve the above object, in the present invention, as a first invention, a video camera accessory is attached to a battery set which is detachably attached to a video camera and supplies power to a video camera circuit. A hot set to be attached, and a power supply means that, when a current flows from the battery set to the video camera circuit, operates according to the current and supplies power from the battery set to the video camera accessory through the hot set. We propose a power supply control device for a video camera accessory.

As a second invention, a hot set for attaching a video camera accessory to a battery set which is detachably attached to the video camera and supplies electric power to the video camera circuit, and a current flowing from the battery set to the video camera circuit is detected. A power supply control device for a video camera accessory is provided, which comprises a signal supply circuit that sends an ON / OFF signal to the video camera accessory via the hot shoe in response to power supply and stop of power supply. .

[0009]

When a current flows from the battery set attached to the video camera to the video camera circuit, the power supply means provided in the battery set operates to supply battery power to the video camera accessory via the hot shoe. It works automatically according to the video camera. Further, when the current to the video camera circuit is cut off, the power supply to the video camera accessory is also stopped and the video camera accessory becomes inoperative.

On the other hand, in the invention in which the signal supply circuit is provided in the battery set, an on / off signal is given to a video camera accessory having an internal power source to operate the video camera accessory in accordance with the video camera, and to operate. Can be stopped.

[0011]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a perspective view of a video camera equipped with a power supply control device attached to a video camera, and FIG. 2 is a circuit diagram of the power supply control device.

From these drawings, 51 is a video camera,
Reference numeral 52 is a battery set, and 53 is a monitor TV as an accessory. The video camera 51 does not have an internal power source, but is equipped with a detachable battery set 52 and is operated by the battery power of the battery set 52.

This video camera 51 is a known one, and is provided with a video camera circuit 54 including therein various circuits necessary for the video camera such as a tape feed motor, lens adjustment and exposure control, and an external circuit. In addition to a power switch (not shown), a switching operation button 55 capable of switching between shooting preparation and shooting operation is provided.

When the switching operation button 55 is set to the shooting preparation position, the shooting preparation switch 56 shown in FIG. 2 is closed to operate the video camera circuit 54 for the shooting preparation operation.
When the camera is in the shooting position, the shooting operation switch 57 is closed under the closing of the switch 56 and the video camera circuit 5 is closed.
The main circuit 54b for operating the image pickup 4 is operated.

The battery set 52 is provided with a hot shoe 58 at an upper position, and is internally provided with a battery 59 and a power supply circuit for supplying battery power to a video camera accessory.

The power supply circuit has a power supply means composed of a normally open electromagnetic switch 60, as shown in FIG. The electromagnetic switch 60 is composed of an electromagnetic coil 60a and a switch element 60b, and the video camera circuit 54 has a battery 5
When the power is supplied by 9, a current flows through the electromagnetic coil 60a to excite it, thereby closing the switch element 60b.

In a monitor television 53 as an accessory to a video camera, a television main body 53a and a supporting portion 53b are connected to each other 53.
connected by c. The connecting portion 53c has a support shaft structure capable of turning the television main body 53a to the left and right and in the up and down direction, and the screen angle can be appropriately changed.

This monitor TV 53 does not have an internal power source, and the support portion 53b can be attached to the hot shoe 58.
It operates by the battery power supplied via the hot shoe 58. In addition, the support portion 53b
The television main body 53a and the television main body 53a are connected by a power cord 61 to supply battery power.
The door 61 may be passed through the inside of the support portion 53b and the connecting portion 53c.

Further, the monitor television 53 is adapted to project the subject photographed by the video camera 51 on the screen, and at the time of reproduction, project the photographed image on the screen.
Therefore, the video camera 51 and the television main body 53a are connected by a code 62 for transmitting an image signal and a reproduction signal.

Terminals 58a and 58b shown in FIG. 2 are terminals provided on the hot shoe 58, terminals 53d and 53e are terminals provided on the lower end of the supporting portion of the monitor television 53, and the monitor television 53 is the hot shoe 58 of the battery set 52.
Each of these terminals is electrically connected by mounting on.

Next, the operation of the power supply control circuit shown in FIG. 2 will be described. When the power switch is turned on to the video camera 51 and the switching operation button 55 is at the shooting preparation position,
The shooting preparation switch 56 is closed, and a battery current flows from the battery 59 to the video camera circuit 54 and the electromagnetic switch 60. At this time, in the video camera circuit 54, the sub circuit 54a for preparation for shooting operates, and at this stage, the main circuit 54b is in the non-operating state, and the shooting operation is not performed.

When a current flows through the electromagnetic switch 60, the switch element 60b is closed by the excitation of the electromagnetic switch 60, and battery power is supplied to the monitor television 53 via the hot shoe 58 of the battery set 52, so that the monitor television 53 operates. Operate. As a result, the subject in video shooting is displayed on the screen of the monitor television.

When the switching operation button 55 is set to the shooting position, the shooting operation switch 57 is closed under the closing of the shooting preparation switch 56, the main circuit 54b of the video camera circuit 54 is operated, and the operation of the monitor TV 53 is operated. A video shoot is done below.

When the switching operation button 55 is switched from the shooting position to the shooting preparation position, the shooting operation switch 57 is opened and the video shooting is stopped. Further, when the power switch of the video camera 51 is switched from on to off, the video camera Circuit 5
4 and the electromagnetic switch 60 cut off the battery current, and when the electromagnetic switch 60 returns, the switch element 6
0b is opened, and the screen of the monitor TV 53 is turned off.

As described above, the monitor television 53 as an accessory to the video camera automatically starts its operation when power is supplied to the video camera circuit 54 provided in the video camera 51.
When the power supply is completed, the operation is automatically stopped.

In this embodiment, the battery set 52 supplies power to the monitor television 53, but an accessory such as a sound collecting microphone or video light is connected to the hot shoe 58 to supply power in the same manner. can do. In this case, electric terminals are provided on the supporting portions of these accessories so as to be electrically connected to the hot shoe terminals. Also,
If a video signal transmitter is connected instead of the monitor television 53, the video can be transmitted and displayed on a television receiver at a remote position.

In the above embodiment, the case where the video camera accessory does not have a built-in power source has been described. However, when the video camera accessory has a built-in power source, the power supply circuit is a signal supply circuit. And work. That is, when the power switch of the video camera 51 is turned on to prepare for shooting, the shooting preparation switch 56 is closed in FIG. 1, and the switch element 60b is closed by the excitation of the electromagnetic switch 60. Therefore, hot shoe 58
A battery current flows from the monitor television 53 to the monitor television 53, and this becomes an ON signal of the built-in power source of the monitor television 53, and the monitor television 53 is powered by the built-in power source to operate.

On the other hand, when the video camera 51 finishes shooting and the power switch of the video camera 51 is switched from ON to OFF, the battery current flowing through the video camera circuit 54 and the electromagnetic switch 60 is cut off, and the electromagnetic switch 60 is restored. The switch element 60b is opened. As a result, the battery current flowing from the hot shoe 58 to the monitor television 53 is shut off, and this becomes an off signal of the built-in power source of the monitor television 53, and the monitor television 53 turns off the screen.

Next, another embodiment of the power feeding control device shown in the above embodiment will be described. In the description of this embodiment, the same members as those in the above embodiment are designated by the same reference numerals and the description thereof will be omitted.

3 to 5 are constructed by providing a switch for turning on and off by utilizing the electromagnetic force generated in the coil. In the embodiment of FIG. 3, the switch element 60b of the electromagnetic switch 60 is closed. When the base current flows, the monitor TV 53 is turned on by the transistor 63.
It is configured to be operated by being supplied with power.

In the embodiment shown in FIG. 4, the coil 64 is connected in series between the video camera circuit 54 and the battery 59, and the transistor 6 is turned on by the electromotive force generated in the coil 64.
5, the monitor television 53 is supplied with power from the battery 59.

In the embodiment of FIG. 5, a capacitor 67 is provided in parallel with a coil 66 connected in series between the video camera circuit 54 and the battery 59, and a differential voltage is generated by the voltage of the capacitor 67 charged by the voltage generated in the coil 66. Amplifier 6
8, the transistor 70 is turned on by this inverted output, and the monitor television 53 is supplied with power from the battery 59.

In the embodiment of FIG. 6, the photo coupler 71 is used.
A photocoupler including a light-emitting diode 71a through which a battery current flows by closing the photographing preparation switch 56 and a photo-diode 71b that receives the light emitted by the light-emitting diode 71a and photoelectrically converts it. 71 is formed, and the photoelectric conversion current of the photo diode 71b is based.
The monitor transistor 53 is operated by the switching transistor 72 that is turned on and turned on.

In the embodiment of FIGS. 7 and 8, a transistor for switching operation is connected in series between the video camera circuit 54 and the battery 59. In the embodiment of FIG. 7, the photographing preparation switch 56 is closed. 8 includes a transistor 73 which is turned on by a base current flowing therethrough. In the embodiment shown in FIG. 8, the transistor 7 is turned on when the transistor 75 is turned on.
4 is provided. In the case of FIG. 7, the monitor television 53 operates by turning on the transistor 73, and in the case of FIG. 8, turning on the transistor 75.

The embodiment shown in FIGS. 9 and 10 comprises a photocoupler and a switching transistor. The embodiment shown in FIG. 9 has a photocoupler 77 which outputs a photoelectric conversion current when the transistor 76 is turned on. A transistor 78 for turning on the photoelectrically converted current based on the input is provided, and the monitor television 53 operates by turning on the transistor 78. Further, the embodiment of FIG. 10 is provided with a photocoupler 80 which outputs a photoelectric conversion current when the transistor 79 is turned on, and a transistor 81 which receives the photoelectric conversion current as a base input and is turned on. The monitor television 53 is configured to operate.

Further, the embodiment shown in FIG. 11 is provided with an illuminance detecting element 82 which is effective when a video light is mounted as a video camera accessory.
The switch element 84 is closed, the two switching transistors 85 and 86 are turned on, and the light source 87 for light is turned on. However, when the subject is bright, the resistance value of the detection element 82 decreases, so that the transistors 85 and 86 remain off and the light source 87 for light does not light.

[0037]

As described above, the power supply control device according to the present invention supplies the battery power from the hot shoe to the video camera accessory connected to the hot shoe of the battery set according to the current flowing in the video camera circuit. Therefore, the conventional adapter is unnecessary, and the video camera accessory can be used with less cost burden.

Further, since the video camera accessory automatically operates in accordance with the video camera, it does not take much time to shoot the video, and the power supply control device is very easy to use.

Further, the power supply control device can be used not only for the video camera accessory using the external power source but also for the video camera accessory equipped with the internal power source.
Widely used and convenient.

[Brief description of drawings]

FIG. 1 is a perspective view of a video camera including a power supply control device according to the present invention.

FIG. 2 is a circuit diagram showing an embodiment of the power supply control device described above.

FIG. 3 is a simplified circuit diagram showing another embodiment of the power supply control device of the present invention.

FIG. 4 is a simplified circuit diagram showing another embodiment of the power supply control device of the present invention.

FIG. 5 is a simplified circuit diagram showing another embodiment of the power supply control device of the present invention.

FIG. 6 is a simplified circuit diagram showing another embodiment of the power supply control device of the present invention.

FIG. 7 is a schematic circuit diagram showing another embodiment of the power supply control device of the present invention.

FIG. 8 is a simplified circuit diagram showing another embodiment of the power supply control device of the present invention.

FIG. 9 is a simplified circuit diagram showing another embodiment of the power feeding control device of the present invention.

FIG. 10 is a simplified circuit diagram showing another embodiment of the power supply control device of the present invention.

FIG. 11 is a schematic circuit diagram showing another embodiment of the power supply control device of the present invention.

[Explanation of symbols]

 51 video camera 52 battery set 53 monitor TV 54 video camera circuit 58 hot shoe 59 battery 60 electromagnetic switch

Claims (2)

[Claims] 1. A hot set for attaching a video camera accessory to a battery set that is detachably attached to the video camera and supplies power to the video camera circuit, and when a current flows from the battery set to the video camera circuit, the hot set is performed according to the current. A power supply control device for a video camera accessory, comprising: a power supply unit that operates to supply power from a battery set to the video camera accessory via the hot shoe. 2. A hot set for attaching a video camera accessory to a battery set that is detachably attached to a video camera and supplies power to the video camera circuit, and a current flowing from the battery set to the video camera circuit is detected to stop and supply the power. A power supply control device for a video camera accessory, comprising: a signal supply circuit for transmitting an ON / OFF signal output in response to the video camera accessory via the hot shoe.