JP3276838B2 - Video camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a mechanism for displaying a charge state of a video camera.

[0002]

2. Description of the Related Art Rechargeable electronic devices or charging devices include:
It has a means for displaying the state of charge, indicating that charging is in progress, displaying standard charging, charging mode such as quick charging,
Alternatively, the elapsed time from the start of charging is displayed. As a device for displaying the state of charge, for example, JP-A-2-7023
7 and JP-A-3-289329. JP 2
The charging device of -70237 includes a lamp indicating that charging is in progress, a lamp indicating charging mode, and a display indicating the elapsed time from the start of charging.
The 29 electric reel with an automatic charging stop function uses an LCD as a means for displaying the state of charge.

[0003]

In the video camera (1), a display (9) for a viewfinder or a monitor for photographed images is provided.
If the charging status is displayed on the display (9), there is no need to provide the lamp or a dedicated display.
On the other hand, a CRT or a transmissive LCD is used as the display (9), but a CRT or LCD backlight consumes a large amount of power. Therefore, it is inefficient to always display the state of charge on the display (9) as described in JP-A-2-70237 and JP-A-3-289329. Therefore, a switch for turning on / off the display of the charge state may be provided in the video camera (1). However, providing a new operation article complicates the operation and increases the burden on the user.

[0004]

The object of the present invention is to provide a video camera (1) which does not require any special operation for turning on and off the display of the state of charge, and automatically displays the state of charge on the display (9) only when necessary. The purpose is to provide.

[0005]

A video camera body has a secondary battery.
(4) a charging means (3) for the secondary battery (4) and a display (9) movable with respect to the main body, and a current is supplied from the DC power supply (2) via the charging means (3) to the secondary battery. A video camera having switch means for supplying the battery to (4) for charging, turning on the electric circuit of the display by moving the display (9) from the storage position, and turning it off by returning to the storage position; When the power switch (5) of the video camera body is set to the charging side, charging starts. When the switch means is turned on during charging, the electric circuit of the display (9) is turned on and the charging state is displayed on the display (9). it can.

[0006]

During charging, the switch means turns off the electric circuit of the display and displays nothing on the display when the display is in the storage position. When the user wants to know the state of charge, the display is moved to a position where the user can look or see. At this time, the switch means turns on the electric circuit by moving the display, and displays the state of charge on the display. Then, when the user returns the display to the original storage position, the switch means turns off the electric circuit again.

[0007]

[Effect] The charging state can be displayed on the display during charging. When the display is in the stowed position, the electric circuit of the display is turned off, so that the consumption of electricity during charging can be reduced and there is no waste. In addition, since the user does not need to learn how to operate the new operation article, the burden on the user does not increase.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a portable video camera (1) of the present invention. The camera (1)
It has a rotating body (10) having a viewfinder (90), and the rotating body (10) has a camera (1) body so that a user can look into the viewfinder (90) from various angles. , Is provided so as to be rotatable from a horizontal direction to a substantially vertical direction. Further, the video camera (1) includes a secondary battery (4), and the entire video camera (1) is operated by the battery (4). In this embodiment, a nickel-cadmium storage battery is used as the secondary battery (4). When charging the secondary battery (4), the video camera (1) is connected to an AC adapter connected to an AC power supply or a DC power supply (2) such as a car battery, and is usually connected to a user such as a floor. It is located lower than the line of sight. Therefore, the switch means is provided so that when the rotating body (10) is rotated in the vertical direction, the electric circuit of the viewfinder (90) is turned on and the state of charge is displayed. That is, as shown in FIG.
Has a viewfinder (90) at one end and a projecting piece (11) at the other end. The video camera (1) body has a slot (1) in which the protruding piece (11) slides by the rotation of the rotating body (10).
Form 3). Then, as shown in FIG.
(1) A limit switch (12) is provided at a position in the main body that comes into contact with the protruding piece (11) when the rotating body (10) is rotated in the vertical direction. The limit switch (12) is set to be normally off, and to be turned on when pressed by the protruding piece (11).

By the way, as a method of charging the discharged secondary battery (4), there are standard charging, rapid charging and short-time charging in between. Standard charging is a method of charging for about 10 hours with a current of about 1/10 of the value of the rated capacity (unit: Ah),
The rapid charging is a method of charging for about one hour with a current substantially equal to the rated capacity value. Here, the rated capacity is a standard amount of electricity that can be taken out from a fully charged battery. In addition, there is trickle charging in which charging is performed with a current of about 1/30 of the rated capacity value in order to supplement self-discharge from the charged secondary battery (4). In the case of quick charging, charging is completed in a short time, but a large current is required as compared with other methods, so a large-capacity DC power supply (2) must be used. Furthermore, a control circuit for preventing overcharging is required. In the case of standard charging, the charging time is long and the voltage difference and the temperature difference between the battery at the start of charging and the battery at the completion of charging are small, so it is difficult to know how much the battery is charged. Therefore, in the present embodiment, from the viewpoint of miniaturization, reduction in the number of parts, etc., standard charging and trickle charging are used as charging methods, and the elapsed time from the start of charging is displayed as a guide to know the progress of charging. .

Next, the configuration on the circuit side will be described. As shown in FIG. 2, the secondary battery (4) is connected to a means (3) for charging the battery (4), and the charging means (3) comprises a DC power supply.
Connected to (2). In this embodiment, as the charging means (3), a standard charging resistor (30) (resistance value R1) and a trickle charging resistor (31) (resistance value R2) are connected in parallel.
It is connected to a secondary battery (4) and a DC power supply (2). The standard charging resistor (30) is connected to a charge mode changeover switch (32) for turning on and off the current flowing through the resistor (30), and the changeover switch (32) is turned on and off by the CPU (6). Is controlled by
In the case of standard charging, the changeover switch (32) turns on,
The resistance value R of the charging means (3) is represented by a composite value R = R1 × R2 /
(R1 + R2). In the case of trickle charging, the changeover switch (32) is turned off, and the resistance value R of the charging means (3) is changed.
Becomes the resistance value R2 of the trickle charge resistor (31),
It becomes larger than the resistance value when turned on. Therefore, the charging current for trickle charging is smaller than the standard charging. CP
U (6) detects signals from the power switch (5), the limit switch (12) and the timer circuit (7), and selects the changeover switch (32), the timer circuit (7), the character generation circuit (80) and It controls the electric circuit of the display (9).

When the power switch (5) of the video camera (1) is set to the CHARGE position, the CPU (6)
The changeover switch (32) of the charging means (3) is turned on, and an instruction to operate the timer circuit (7) is issued to start standard charging. 10 minutes from the start of charging by the timer circuit (7)
When the CPU (6) detects that the time has elapsed, the CPU (6)
In (6), the changeover switch (32) is turned off to switch to trickle charging. During this time, as shown in FIG. 1B, when the display switch (12) is turned on by the rotation of the rotating body (10), the CPU (6) turns on the electric circuit of the viewfinder (90), The elapsed time from the start of charging obtained from the timer circuit (7) is instructed to the character generation circuit (80) as the charging state display means (8) and displayed on the viewfinder (90). Then, when the rotating body (10) is rotated to the original position and the display switch (12) is turned off, the CPU (6) turns off the electric circuit of the viewfinder (90).

As described above, the electric circuit of the viewfinder (90) is turned on only when necessary, and the state of charge is displayed, so that power consumption during charging can be suppressed. Also,
Since the switch is turned on and off by the rotating body (10), there is no need for the user to learn how to operate new parts,
Operation is not complicated.

The description of the above embodiments is for the purpose of describing the present invention, and should not be construed as limiting the invention described in the claims or reducing the scope thereof. or,
The configuration of each part of the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made within the technical scope described in the claims. For example, in the present embodiment, the limit switch (12) is provided as the switch means, but any switch means such as a contact switch, a proximity switch, and a sensor can be used. Further, in this embodiment, the switch (12) is provided in the video camera (1) main body, and the rotating body (1) is provided.
Although the protruding piece (11) is provided in (0), even if each is replaced, the operation and effect of the present invention do not change. In this embodiment, the switch is provided in the viewfinder (90). However, if the video camera has a movable monitor, the switch may be provided in the monitor. Further, in the present embodiment, only the standard charging and the trickle charging are used as the charging means (3) from the viewpoint of reducing the weight and size of the video camera (1), and the elapsed time from the start of charging is determined by the viewfinder (90). ), The most suitable charging means (3) such as quick charging can be used, and other charging states such as charging rate can also be displayed. Further, in this embodiment, a nickel-cadmium storage battery is used as the secondary battery (4), but another secondary battery such as a nickel-metal hydride storage battery or a lithium secondary battery can be used. In that case, if it is a nickel hydrogen storage battery,
The timer circuit (7) is indispensable to prevent overcharging, and in the case of a lithium secondary battery, a constant voltage circuit must be provided as the charging means (3) in order to perform constant voltage charging.

[Brief description of the drawings]

FIG. 1 is a side view of a video camera according to the present invention with a part cut away, in which (a) shows a state in which a viewfinder is turned down, and (b) shows a state in which the viewfinder is raised.

FIG. 2 is a block diagram showing connections between components related to charging a secondary battery.

[Explanation of symbols]

 (1) Video camera (4) Secondary battery (9) Display (12) Charge status display switch

Claims (1)

(57) [Claims] 1. A video camera body comprising a secondary battery (4), charging means (3) for the secondary battery (4), and a display (9) movable with respect to the main body. A current is supplied to the secondary battery (4) through the charging means (3) to perform charging, and the electric circuit of the display is turned on by moving the display (9) from the storage position, and is returned to the storage position. When the power switch (5) of the video camera body is set to the charging side, charging is started. When the switch is turned on during charging, the electric circuit of the display (9) is turned on. A video camera capable of displaying a charge state on a display (9).