JPH0669267B2 - Power supply for electronic equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a power supply device for electronic equipment, and more particularly to a power supply device for electronic equipment driven by a secondary battery.

[Outline of Invention]

The present invention provides a case having substantially the same shape as the case for storing the secondary battery, stores the dry battery in the case, and further incorporates at least a constant voltage circuit into the case. Instead of the case containing the next battery, the case containing the dry battery is attached to the electronic device so that the electronic device can be driven by the dry battery.

[Conventional technology]

For example, a video camera with a built-in VTR has a nickel
Secondary batteries such as cadmium batteries and lead batteries have been used, and these secondary batteries are packed into a camera and mounted on the camera to drive the camera.
This is because the video camera is driven by supplying a certain amount of current. Therefore, in such a video camera, when the secondary battery is discharged, it is charged and used.

[Problems to be solved by the invention]

When the electronic device is driven by the secondary battery as described above, the electronic device cannot be used immediately when the secondary battery is discharged, and it is necessary to wait until the charging is completed. Therefore, when a nickel-cadmium battery is used, even if the battery is charged rapidly, it takes about one hour for charging, and the video camera cannot be used during this time. Also, if the battery is discharged outdoors,
It cannot be charged immediately, which has the drawback of rendering the video camera unusable.

In consideration of such problems, it is considered to use the dry battery as it is.However, when a normal dry battery is used instead of the nickel-cadmium battery, a large load is applied to this battery and the terminal voltage is increased. Becomes sharply low, which causes the possibility that the video camera may not operate properly.

The present invention has been made in view of the above problems, and in an electronic device such as a video camera with a built-in VTR, when a secondary battery such as a nickel-cadmium battery is discharged, the device is driven by a dry battery. It is an object of the present invention to provide a power supply device for an electronic device, which is capable of driving.

[Means for solving problems]

The present invention, in an electronic device that is driven by a secondary battery, is provided with a case having substantially the same shape as the case for storing the secondary battery, and to store the dry battery in the case, Further, at least a constant voltage circuit is incorporated into the case, and instead of the case containing the secondary battery, the case containing the dry battery is attached to the electronic device so that the electronic device can be driven by the dry battery. It was done.

[Action]

Therefore, according to the present invention, when the battery pack accommodating the secondary battery is discharged and becomes unusable, the power supply device can drive the electronic device with the dry battery.

〔Example〕

The present invention will be described below with reference to an embodiment shown in the drawings. FIG. 2 shows a VTR built-in video camera 10 including a power supply device according to an embodiment of the present invention. The video camera 10 has a cassette holder 11 on its side surface side. A tape cassette can be installed inside and set in the built-in VTR. An optical lens 12 is attached to the front side of the video camera 10 and a viewfinder 13 is provided on the back side. Also this video camera 10
A grip 14 also serving as a battery holder is provided at the lower part of the so as to extend obliquely forward. This grip 1
A lid plate 15 is attached to the lower part of 4 so that it can be opened and closed.
The lid plate 15 is opened so that the secondary battery pack 16 or the dry battery pack 17 can be mounted. That is, the video camera 10 can be driven by a nickel-cadmium battery by the secondary battery pack 16 and can be driven by a dry battery by the dry battery pack 17.

Next, the dry battery pack 17 will be described. As shown in FIG. 1, FIG. 3, and FIG.
Is provided with a case 18, and a lid plate 19 is attached to the case 18 by a hinge 20 so as to be openable and closable. The lid plate 19 is locked by a lock claw 21 in a closed state. The inside of the lid plate 19 is configured as a dry battery storage space 22. For example, as shown in FIG. 1, four dry batteries 23 are stored and held.

Further, the case 18 of the dry battery pack 17 has an opening 24 formed at an end portion on the front side thereof, and a slider 25 is slidably held in the opening 24. . Further, on the back side of the case 18 of the pack 17, in particular, as shown in an enlarged view in FIG. 4, recesses are formed in the left and right portions on the upper end side, respectively, and a pair of terminal plates are provided so as to face these recesses. 26 is attached. The positions of the opening 24 and the terminal plate 26 are the same as those of the secondary battery pack 16 accommodating the nickel-cadmium battery.

Next, the internal structure of the pack 17 will be described. As shown in FIGS. 1 and 5, a partition wall 27 is formed in the case 18, and the partition wall 27 separates the battery storage space 22 from the battery storage space 22. The circuit board 28 is arranged in the separated space. A switch 29 is mounted on the circuit board 28 together with other circuit components. An upper surface of the switch 29 is provided with an operator 30, and the operator 30 is the slider 25.
It is adapted to be received in the engaging hole 31 of. The predetermined pattern on the circuit board 28 is connected to the terminal board 26 via lead wires 32.

Next, the circuit on the circuit board 28 will be described.
As shown in FIG. 8, the switch 29 is connected to the dry battery 23.
Is connected to the series circuit of the coil 33 and the diode 34. A transistor 35 is connected to the connection point between the coil 33 and the diode 34, and the base of the transistor 35 is connected to the pulse width modulator 36. The pulse width modulator 36 detects the voltage generated at the connection point between the resistor 38 and the variable resistor 39, and modulates the pulse width according to this voltage. Further, the smoothing capacitor 27 is connected in parallel to the series circuit of the resistor 38 and the variable resistor 39, and
The capacitor 37 is connected to the output terminal 43.

In the above configuration, when the battery in the secondary battery pack 16 for driving the video camera 10 shown in FIG. 2 is discharged, the dry battery 23 in the dry battery pack 17 is discharged.
The camera 10 can be driven by. This operation will be described below.
As shown in the figure, the cover plate 15 may be opened and inserted into the grip 14. The grip 14 also serves as a battery holder, and when the pack 17 is inserted therein, it is introduced into the grip 14 as shown in FIG. When the case 18 is inserted against the coil spring 41 mounted inside the grip 14, the erroneous insertion preventing projection 40 provided inside the grip 14 is moved to the case as shown in FIG. 18 is engaged with the opening 24,
A slider 25 slidably held in the opening 24
Will be pressed. The movement of the slider 25 causes the switch 29 to be switched. At the same time, when the dry battery pack 17 is completely inserted into the grip 14, the terminal plate 26 provided on the pack 17 is attached to the grip 14.
The terminal plate 42 provided in the inner part of the terminal is brought into contact with each other to achieve electrical connection.

When the switch 29 is closed by inserting the dry battery pack 17 into the grip 14, the constant voltage circuit shown in FIG. 8 is activated. This constant voltage circuit generates a voltage proportional to the output voltage generated at the output terminal 43 at the connection point between the resistor 38 and the variable resistor 39. The voltage generated at this connection point is field-backed to the pulse width modulator 36. This pulse width modulator 36 produces a pulse formed by the transistor 35 when the output voltage generated at the output terminal 43 is low. Is narrowed to increase the power supplied to the output terminal 43. On the other hand, output terminal 4
If the voltage generated at 3 is high, the pulse width modulator 36 widens the pulse applied to the base of the transistor 35, so that the voltage supplied to the output side is reduced.
As a result, a constant voltage is generated at the output terminal 43. The capacitor 37 absorbs the ripple.

Therefore, according to such a video camera 10, when the camera 10 is used outdoors, etc., the secondary battery pack 1
When the nickel-cadmium battery in 6 is discharged,
By removing the pack 16 and filling the dry battery pack 17 into the grip 14, the camera 1 is immediately removed.
It becomes possible to continue to use 0. It has been confirmed that the video camera 10 can be continuously driven for 30 minutes with four alkaline dry batteries placed in the pack 17. Moreover, since the constant voltage circuit shown in FIG. 8 is incorporated in the pack 17, it is possible to prevent the terminal voltage from dropping due to the load of the camera 10, and it is normal until the dry battery 23 is almost completely consumed. It becomes possible to drive the video camera 10 with the voltage. Therefore, without increasing the number of dry batteries 23 unnecessarily,
It becomes possible to effectively use 3 until the end.

Further, a slider 25 is slidably held in the opening 24 of the case 18 of the dry battery pack 17, and the erroneous insertion preventing projection 40 is provided only when the pack 17 is properly mounted. The slider 25 is moved and the switch 29 is closed. Therefore, this pack 1
Not only can the dry battery 23 be prevented from being discharged before the camera 7 is mounted on the camera 10, but the switch 29 is prevented from closing when the pack 17 is mounted in the grip 14 in an incorrect posture. At the same time, it is being notified that the insertion is wrong. That is, when inserted in an incorrect posture, the erroneous insertion preventing projection 40 comes into contact with the edge of the case 18, so that the case 18 cannot be completely inserted and the lid plate 15 cannot be closed.

Further, according to such a video camera 10, since the video camera 10 can be driven by the dry battery pack 17, the secondary battery pack 17 is not necessarily required. Therefore, when the video camera 10 is purchased, it is not necessary to buy the secondary battery and the charging device for the secondary battery at the same time, which makes it possible to reduce the initial cost. Moreover, since the constant voltage circuit shown in FIG. 8 is incorporated in the dry battery pack 17, the cost of the video camera 10 itself is not increased,
There is no need to add an unnecessary constant voltage circuit to the camera 10 when using only the secondary battery pack 16 to increase the cost.

〔The invention's effect〕

As described above, according to the present invention, a case having substantially the same shape as the case for accommodating the secondary battery is provided, the dry battery is accommodated in the case, and at least the constant voltage circuit is further incorporated in the case. In this way, instead of the case containing the secondary battery, the case containing the dry battery is attached to the electronic device, and the electronic device can be driven by the dry battery. Therefore, according to the present invention, it becomes possible to drive an electronic device, which is normally driven by a secondary battery, by a dry battery as needed, and a voltage drop can be prevented by a constant voltage circuit. It will be possible.

[Brief description of drawings]

FIG. 1 is an external perspective view showing a dry battery pack for a video camera according to an embodiment of the present invention, FIG. 2 is an external perspective view of a video camera using this pack, and FIG. 3 is a dry battery with a door closed. Fig. 4 is an external perspective view of the pack, Fig. 4 is a rear perspective view of the pack, Fig. 5 is a longitudinal sectional view of the pack, Fig. 6 is a transverse sectional view of the pack, and Fig. 7 is an exploded view of a switch switching mechanism. FIG. 8 is a perspective view, and FIG. 8 is a circuit diagram of a constant voltage circuit that works with the switch.
FIG. 9 is a cross-sectional view of the essential parts showing the mounting operation of the pack,
The figure is a cross-sectional view showing a state in which the mounting is completed. In the reference numerals used in the drawings, 10 ... VTR built-in video camera 16 ... Secondary battery pack 17 ... Dry battery pack 18 ... Case 22 ... Dry battery storage space 23 ... Dry battery 28 ... Circuit board 29 ...... It's a switch.

Claims (2)

[Claims] 1. An electronic device driven by a secondary battery is provided with a case having substantially the same shape as a case for housing the secondary battery, and the dry battery is housed in the case. Further, at least a constant voltage circuit is incorporated in this case, and instead of the case containing the secondary battery, the case containing the dry battery is attached to the electronic device, and the electronic device can be driven by the dry battery. A power supply device for electronic equipment, characterized in that 2. The electronic device according to claim 1, wherein the constant voltage circuit is activated only when a case accommodating the dry battery is attached to the electronic device. Power supply.