JP2007080618A - External power supply device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an external power supply device capable of measuring a temperature of a battery correctly regardless of a state of a battery pack to be loaded even if this is the external power supply device with a plurality of numbers of the battery packs built in. <P>SOLUTION: The plurality of the battery packs (1) 90a and the battery packs (2) 90b having the thermisters 92a, 92b are capable of loading in the battery room in the battery holder 80. Either one of contact groups 82a, 82b is conducted to either one of the thermisters 92a, 92b. Then, when the battery pack (1) 90a is loaded into a specific battery room, regardless of a loading state of the battery in other battery rooms, the thermister 92a is conducted to the contact groups 82a, 75. On the other hand, when the battery pack (1) 90a is unloaded into the specific battery room and the battery pack (2) 90b is loaded into another battery room, the thermister 92b is conducted to the contact groups 82b, 75. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an external power supply device, and more particularly to an improvement of an external power supply device incorporating a plurality of battery packs for supplying power to an electronic device such as a camera.

  2. Description of the Related Art Conventionally, a camera that checks the voltage of a battery loaded in a camera body and notifies the remaining battery level is generally used.

  For example, a consumption current value table is prepared for each camera operation circuit, the battery internal resistance is obtained by dummy load, the voltage value is calculated from the internal resistance value and current consumption, and the remaining battery level warning is compared with the battery voltage. Is known (see, for example, Patent Document 1).

As described above, a technique for predicting a battery current by flowing a predetermined current through a dummy load is well known.
JP 2003-344922 A

  By the way, in recent years, an external power supply device that can be freely attached to and detached from the camera body and incorporates a large-capacity battery pack has been developed. Such an external power supply device incorporates a plurality of battery packs.

  On the other hand, since the battery uses a chemical reaction, it is easily affected by the environmental temperature. A technique is known in which such a temperature change is predicted by temperature and referred to a table.

  However, in the camera described in Patent Document 1 described above, temperature does not exist as a parameter. For this reason, when a temperature change occurs, an accurate warning of the remaining battery level cannot be performed.

  Accordingly, an object of the present invention is to provide an external power supply device that can correctly measure the temperature of a battery regardless of the state of the battery pack that is loaded, even if the external power supply device includes a plurality of battery packs. That is.

  That is, the invention according to claim 1 is an external power supply device that enables external power supply to an electronic device, and a plurality of battery chambers each capable of being loaded with a plurality of batteries each having a temperature detection element; When a battery is loaded in a specific battery chamber, which is one of the battery chambers, and an external contact that conducts to one of the temperature detection elements of the battery, is the battery loaded in another battery chamber? Regardless of whether or not a battery is loaded in the specific battery chamber, the temperature detection element of the battery loaded in the specific battery chamber is conducted to the external contact, and the specific battery chamber is connected to the specific battery chamber. Circuit means for conducting the temperature detection element of the battery loaded in the battery chamber to the external contact when the battery is not loaded and the battery chamber other than the specific battery chamber is loaded; It is characterized by comprising.

  According to a second aspect of the present invention, in the first aspect of the invention, the circuit means is connected to the plurality of battery chambers and the external device in conjunction with loading of a battery in the specific battery chamber. It has the transfer switch which switches a connection with a contact.

  According to a third aspect of the present invention, in the first aspect of the present invention, the circuit means includes a plurality of detection switches for detecting loading of the plurality of batteries, and outputs from the plurality of detection switches. It includes a CPU that controls to select one of the temperature detecting elements and to conduct to the external contact.

  According to a fourth aspect of the present invention, there is provided an external power supply device capable of supplying power to an electronic device from outside, a first battery chamber in which a first battery having a first temperature detection element can be loaded; A second battery chamber in which a second battery having a second temperature detection element can be loaded, an external contact connected to one of the temperature detection elements, and the first battery in the first battery chamber. Is loaded and the second battery chamber is not loaded, the first temperature detection element and the external contact are electrically connected, and the second battery is loaded into the second battery chamber. When the first battery chamber is not loaded, the second temperature detection element and the external contact are electrically connected, and the first battery chamber is loaded into the first battery chamber. When the second battery is loaded into the second battery chamber, the first temperature detection element and the external contact are electrically connected to the first temperature detection element. Characterized by comprising circuit means for conducting, the.

  According to a fifth aspect of the present invention, in the invention of the fourth aspect, the circuit means is one of the first battery chamber and the second battery chamber in conjunction with a loaded state of the first battery. And a transfer switch for switching the connection with the external contact.

  According to a sixth aspect of the present invention, in the fourth aspect of the present invention, the circuit means includes a first detection switch for detecting the loading of the first battery and the loading of the second battery. A second detection switch for detection, and a CPU for controlling one of the temperature detection elements to be conducted to the external contact by the output from the first detection switch and the second detection switch. Features.

  According to a seventh aspect of the present invention, in the invention according to any one of the first to sixth aspects, the temperature detecting element is a thermistor.

  The invention according to claim 8 is the invention according to any one of claims 1 to 6, wherein the external power supply device is an external power supply device for a camera.

  The invention according to claim 9 is an external power supply device capable of supplying power to an electronic device from the outside, a plurality of battery chambers each having a plurality of batteries each having a temperature detection element, and the above An external contact that is electrically connected to one of the temperature detection elements of the battery and a temperature detection element of the battery that is inserted last among the plurality of batteries inserted in the plurality of battery chambers are connected to the external contact. And a control means.

  According to a tenth aspect of the present invention, in the ninth aspect of the invention, the external power supply device is an external power supply device for a camera.

  According to an eleventh aspect of the present invention, there is provided an external power supply apparatus capable of supplying power to an electronic device from outside, a first battery chamber in which a first battery having a first temperature detection element can be loaded; A second battery chamber in which a second battery having a second temperature detection element can be loaded, an external contact connected to one of the temperature detection elements, the first battery chamber, and the second battery. Control means for switching the connection between any one of the chambers and the external contact in conjunction with the loaded state of the first battery, and the control means is provided in the first battery chamber with the first battery. When the first battery is loaded and the second battery chamber is not loaded, the first temperature detection element and the external contact are electrically connected to each other, and the second battery is placed in the second battery chamber. Is loaded and the first battery chamber is not loaded, the second temperature detecting element and the external contact When the first battery is loaded into the first battery chamber and the second battery is loaded into the second battery chamber, the first temperature detection element and the first battery are electrically connected. And conducting the external contact.

  According to a twelfth aspect of the present invention, in the invention according to the eleventh aspect, the control means includes a first detection switch for detecting loading of the first battery and loading of the second battery. A second detection switch for detection, and a CPU for controlling one of the temperature detection elements to be conducted to the external contact by the output from the first detection switch and the second detection switch. Features.

  The invention described in claim 13 is the invention described in claim 11 or 12, characterized in that the temperature detecting element is a thermistor.

  The invention described in claim 14 is the invention described in claim 11 or 12, wherein the external power supply device is an external power supply device for a camera.

  According to the present invention, it is possible to provide an external power supply device that can correctly measure the temperature of a battery regardless of the state of the loaded battery pack, even if the external power supply device includes a plurality of battery packs. it can.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 shows a configuration of a single-lens reflex digital camera according to a first embodiment of the present invention, and is an external perspective view seen from the rear.

In FIG. 1, this single-lens reflex digital camera (hereinafter abbreviated as “camera”) 1 is mainly composed of a lens barrel 10 as an interchangeable lens and a camera body 20. A desired lens barrel 10 is detachably set with respect to the front surface.
On the upper surface of the camera body 20, a release button 21, a mode dial 22, a power switch lever 23, a control dial 24, and the like are provided.

  The release button 21 is a button for executing a shooting preparation operation and an exposure operation. The release button 21 is composed of a two-stage switch of a first release switch and a second release switch. When the release button 21 is pressed halfway, the first release switch is turned on to perform photometric processing or Shooting preparation operations such as distance measurement processing are executed. Further, when the release button 21 is fully pressed, the second release switch is turned on and the exposure operation is executed.

  The mode dial 22 is an operation member for setting a shooting mode at the time of shooting. When the mode dial 22 is rotated in a predetermined direction, a shooting mode at the time of shooting is set. The power switch lever 23 is an operation member for turning on / off the power of the camera 1. By turning the power switch lever 23, the main power supply of the camera 1 is switched on / off.

  The control dial 24 is a member for setting shooting information. By operating the control dial 24, various settings are performed during shooting.

  On the back surface of the body unit 20, a liquid crystal monitor 26 as a display means for displaying a photographed image, a menu, and the like, a playback button 27, a menu button 28, a cross key 30, an OK button 31, and eyepiece optics. A system finder 33 and the like are arranged.

  The playback button 27 is a button for switching the operation mode of the camera 1 to a playback mode in which an image can be played back from a JPEG file recorded on a flash ROM 62 or a recording medium 63 described later. The menu button 28 is a button for displaying a menu screen on the liquid crystal monitor 26. This menu screen is composed of menu items having a plurality of hierarchical structures. The user can select a desired menu item with the cross key 30 and can determine the item selected with the OK button 31.

  FIG. 2 is a block diagram showing the system configuration of the camera according to the first embodiment of the present invention.

  In FIG. 2, the lens barrel 10 can be detachably mounted via a lens mount (not shown) provided on the front surface of the camera body 20. The lens barrel 10 includes a photographing optical system 11 having a photographing lens, a diaphragm 12, a lens driving mechanism 13, a diaphragm driving mechanism 14, and a lens control microcomputer (hereinafter abbreviated as Lμcom) 15. It is composed of

  The photographing optical system 11 is driven in the optical axis direction by a DC motor (not shown) existing in the lens driving mechanism 13. The diaphragm 12 is driven by a stepping motor (not shown) existing in the diaphragm driving mechanism 14. The Lμcom 15 drives and controls each part in the lens barrel 10 such as the lens driving mechanism 13 and the aperture driving mechanism 14. The Lμcom 15 is electrically connected to a later-described body control microcomputer 65 via the communication connector 35, and is controlled according to a command from the body control microcomputer 65.

  On the other hand, the camera body 20 is configured as follows.

  A light beam from a subject (not shown) that enters through the photographing optical system 11 and the diaphragm 12 in the lens barrel 10 is reflected by a reflecting mirror 40 that is a movable mirror, and passes through a focusing screen, a finder optical system 41, and the like (not shown). To the eyepiece lens 42. An AF sensor unit for performing automatic distance measurement is reflected by a sub-mirror 47 that operates independently of the reflecting mirror 40, and a part of the subject luminous flux that has passed through the half mirror portion in the reflecting mirror 40. 48.

  Behind the reflecting mirror 40 on the optical axis is a focal plane shutter 50 and a photoelectric conversion element of an imaging optical system for photoelectrically converting a subject image that has passed through the optical system, and is composed of a CCD or the like. An imaging element 51 for photographing is provided. That is, when the reflecting mirror 40 is retracted from the photographing optical path, the light flux that has passed through the photographing optical system 11 and the diaphragm 12 is imaged on the imaging surface of the photographing imaging element 51.

  In the vicinity of the finder optical system 41, a display image sensor 43 for displaying a through image and a photometric circuit 44 including a photometric sensor are arranged. The display image sensor 43 and the image sensor 51 are connected to an image processing controller 60 for performing image processing via an interface circuit 59. The image processing controller 60 is connected to the liquid crystal monitor 26 described above and the SDRAM 61, the Flash ROM 62, the recording medium 63, and the like provided as storage areas. These are configured to provide an electronic recording display function together with an electronic imaging function.

  The interface circuit 59 is also connected to the body control microcomputer 65. From the interface circuit 59, a signal indicating the timing of imaging input from the display imaging element 43 and the imaging imaging element 51 is supplied to the body control microcomputer 65.

  The recording medium 63 is an external recording medium such as various memory cards and an external hard disk drive (HDD) that can be attached to and detached from the camera body 20 via a camera interface (not shown).

  The image processing controller 60 includes a photometry circuit 44, an AF sensor drive circuit 53, a mirror drive mechanism 54, a shutter charge mechanism 55, a shutter control circuit 56, and a non-volatile memory (EEPROM) 67. It is connected to a body control microcomputer (hereinafter abbreviated as Bμcom) 65, which is a control means for controlling each part.

  The Bμcom 65 is also connected with an operation display LCD 68 for notifying the photographer of the operation state of the camera by display output, a camera operation switch (SW) 69, and a power supply circuit 70. Further, a battery holder 80 described later is connected to the Bμcom 65 and the power supply circuit 70 via a contact group 75.

  The Bμcom 65 and Lμcom 15 are electrically connected to each other via the communication connector 35 when the lens barrel 10 is mounted. As a digital camera, the Lμcom 15 is operated in cooperation with the Bμcom 65 in a dependent manner.

  The photometric circuit 44 is a circuit that performs photometric processing based on an electric signal of a photometric sensor (not shown). The AF sensor driving circuit 53 is a circuit for driving and controlling the AF sensor unit 48, and the mirror driving mechanism 54 is a mechanism for driving and controlling the reflecting mirror 40 so as to be rotatable. The shutter charge mechanism 55 charges a spring that drives a front curtain and a rear curtain (not shown) constituting the shutter 50. The shutter control circuit 56 controls the movement of the front curtain and the rear curtain of the shutter 50 and transmits / receives a signal for controlling the opening / closing operation of the shutter to / from the Bμcom 65.

  The non-volatile memory 67 stores predetermined control parameters necessary for camera control as a storage area other than the SDRAM 61, the Flash ROM 62, and the recording medium 63 described above, and is provided so as to be accessible from the Bμcom 65.

  The operation display LCD 68 is for notifying the user of the operation state of the camera by display output. The camera operation switch 69, for example, instructs execution of a photographing operation and, as will be described later, a release switch that switches the reflecting mirror 40 in and out of the photographing optical path, a mode change switch that switches between a photographing mode and an image display mode, a power switch, and the like. The switch group includes operation buttons necessary for operating the camera. Furthermore, the power supply circuit 70 is provided to convert the voltage of a battery loaded in a battery holder 80, which will be described later, as a power supply into a voltage required by each circuit unit of the camera system.

  The battery holder 80 can be loaded with a plurality of battery packs. In this embodiment, the battery pack 1 (hereinafter referred to as battery pack (1)) 90a as a first battery is used. And two battery packs 2 (hereinafter referred to as battery pack (2)) 90b as second batteries can be loaded.

  The battery holder 80 includes a first release switch (1RSW) 85 between a contact group 75 with the camera body 20 and contact groups 82a and 82b with the battery pack (1) 90a and the battery pack (2) 90b. A second release switch (2RSW) 86, a lock switch (SW) 87, and backflow prevention diodes D1 and D2 are connected as shown.

  As shown in FIG. 8, the first release switch 85 and the second release switch 86 correspond to the release button 121 provided on the battery holder 80, and have the same function as the release button 21 of the camera body 20 described above. It is. The lock switch 87 is a switch corresponding to the lock lever shown in FIG. 8, and the battery holder 80 is moved to the camera body 20 by operating the lock lever 120 after the battery holder 80 is loaded in the camera body 20. It is locked so as not to come off. At this time, the lock switch 87 is turned on.

  Battery packs (1) 90a and (2) 90b are electrically connected to circuits in battery holder 80 via contact groups 82a and 82b, respectively. Further, the battery cells 91a and 92b connected in series and thermistors 92a and 92b, which are temperature detection elements, are configured.

  FIG. 3 is an external perspective view of the battery pack described above.

  In FIG. 3, the battery pack 90 is shown, but the battery pack (1) 90a and the battery pack (2) 90b in FIG. Will be described.

  The battery pack 90 has a battery cell and a thermistor inside, and the outside is sealed by a case 95. And the connection terminals 96-98 corresponding to the contact group 82a or 82b mentioned above are provided in the predetermined part of the case 95. FIG. Among these, the connection terminal 96 is an anode (+) terminal, the connection terminal 97 is a terminal for the thermistor (T), and the connection terminal 98 is a negative electrode (−) terminal.

  FIG. 4 is a diagram showing the discharge characteristics of the battery in the battery pack.

  As shown in FIG. 4, this battery needs to be charged because the voltage value is gradually discharged from about 8 V and decreases and falls below the voltage value necessary for driving the camera at a predetermined judgment threshold value. . In this case, the determination threshold value is, for example, 6.6 V at 0 ° C., 6.8 V at 20 ° C., and 7.0 V at 45 ° C.

  FIG. 5 is an external perspective view showing the configuration of the battery holder 80 of the camera according to the first embodiment of the present invention, and FIG. 6 shows how the battery pack is mounted on the battery holder of FIG. It is an external perspective view.

  A battery as a power source of the camera is usually loaded in a battery chamber (not shown) provided in the grip portion of the camera body 20. And when using the battery holder 80, it replaces with the battery in this battery chamber, and the contact support | pillar 100 of the battery holder 80 is inserted.

  The battery adapter 80 is provided with a contact column 100 corresponding to the battery chamber as a portion to be inserted into the battery chamber (not shown) of the camera body 20 described above. Corresponding connection terminals 101 to 103 are formed at predetermined positions of the contact support column 100, that is, at positions where they are in electrical contact with electrical contacts (not shown) provided in the battery chamber. Among these, the connection terminal 101 is an anode (+) terminal, the connection terminal 102 is a terminal for the thermistor (T), and the connection terminal 103 is a negative electrode (−) terminal. The contact group 75 described above is constituted by the connection terminals in the camera body 20 and the connection terminals 101 to 103 of the contact columns.

  Further, the contact column 100 is provided with signal lines 111 to 113 that constitute the other contact group 75 adjacent to the connection terminals 101 to 103. These are composed of a signal line 111 for the first release switch, a signal line 112 for the second release switch, and an activation signal line 113.

  The battery holder 80 also has a tripod screw 105 formed at a position facing the bottom surface of the camera body 20 and facing a tripod screw (not shown). The tripod screw 105 is formed of a male screw that is screwed with a tripod screw on the camera body 20 side.

  The horizontal cross-sectional shape of the contact column 100 is slightly smaller than the horizontal cross-sectional shape of a battery chamber (not shown) of the camera body 20. The tripod screw 105 is loosely fitted with a tripod screw hole on the upper surface of the battery holder 80.

  A tripod screw dial 106 for screwing the tripod screw 105 with a tripod screw (not shown) of the camera body 20 is provided on the front surface of the battery holder 80. By rotating the tripod screw dial 106 in a predetermined direction, the screwing state of the tripod screw 105 (not shown) between the tripod screw 105 and the camera body 20 is adjusted, and the battery holder 80 and the camera body 20 are attached and detached. It is like that.

  Further, in the battery holder 80, below the tripod screw dial 106, there are first and second battery chambers 110a and 110b in which a plurality of battery packs 90, in this embodiment two battery packs can be loaded. Is formed. These first and second battery chambers 110a and 110b are provided with a cover 107 that can be freely opened and closed. The cover 107 can be opened and closed by operating the lock lever 108. When the battery pack 90 is loaded, the cover 107 is opened, the battery pack 90 is inserted in the direction of arrow A in FIG. 6, the cover 107 is closed, and the lock lever 108 is operated. As a result, the cover 107 is fixed to prevent the battery pack 90 from falling off.

The battery compartment 110 of the battery holder 80, as shown in FIG. 7, the battery loading switch 117 is operated when the battery pack 90 is inserted in the arrow A ₁ direction is provided. The battery loading switch 117 includes a detection lever 115 and a switch 116.

Now, when the battery pack 90 is inserted into an arrow A ₁ direction, the detection lever 115 in contact, whereby the detection lever 115 is rotated in the arrow B direction. Then, the detection lever 115 depresses the segment of the switch 116 and the battery loading switch 117 is turned on. Thereby, it is detected that the battery pack 90 is loaded in the battery chamber 110 of the battery holder 80. If the battery loading switch 117 is off, the battery pack 90 is not loaded in the battery chamber 110.

  7 shows only one battery chamber 110 and one battery loading switch 117, these may be provided according to the number of battery chambers. The configuration of the battery loading switch is not limited to this as long as it detects the presence or absence of a battery pack in the battery chamber.

  Further, the side surface of the battery holder 80 has a connector cap 109 for covering a connection terminal for connecting a remote control switch (not shown).

  8 and 9 are external views showing a state when the battery holder 80 is attached to the camera body 20, FIG. 8 is a perspective view seen from the lower front side of the camera, and FIG. 9 is a rear view of the camera. FIG.

  As described above, the contact support column 100 of the battery holder 80 is inserted into the battery chamber in the camera body 20, and the tripod screw dial 106 is rotated in the direction of arrow C in FIG. A tripod screw (not shown) of the main body 20 is screwed to attach the battery holder 80 to the camera main body 20. Then, when the lock lever 120 provided on the lower surface of the battery holder 80 is operated, the battery holder 80 is locked so as not to be detached from the camera body 20.

  A release button 121 is provided on the battery holder 80 and corresponds to the first release switch 85 and the second release switch 86 described above. The release button 121 functions in the same manner as the release button 21 when the battery holder 80 is attached to the camera body 20.

  The camera body 20 and the battery holder 80 described above are made of a mold or plastic.

  FIG. 10 is a schematic electric circuit diagram for explaining temperature detection of the battery pack.

In the camera body 20, the AD port 1 of the Bμcom 65 is connected to the power supply circuit 70 through the resistor R 11 and is connected to the thermistor contact 75 ₂ of the contact group 75. On the other hand, AD port 2 of Bμcom65 via the voltage dividing resistors R12 is connected to the positive electrode contacts 75 ₁ of the power source circuit 70 and the contact group 75, is connected to ground via a voltage dividing resistor R13. Also, contacts 75 ₄ , 75 ₅ and 75 ₆ corresponding to the signal line 111 for the first release switch, the signal line 112 for the second release switch, and the activation signal line 113 in the power supply circuit 70 and the contact group 75, Each is connected to Bμcom65.

Battery holder 80, the diode D1 is connected between the contacts 75 ₁ and the battery pack (1) for a positive electrode contacts 82a ₁ of 90a of the camera body 20. Further, the contact 75 ₂ and the battery pack of the camera body 20 (1) between the thermistor contacts 82a ₂ of 90a, switches the connection destination in accordance with the mounted state of the battery pack as described later transfer switch (SW) 83 is connected. The negative electrode contact 75 ₃ of the camera body 20 is connected to the negative electrode contact 82a ₃ of the battery pack (1) 90a. Similarly, a diode D2 is connected between the contact 75 ₁ and the positive contact 82b ₁ of the battery pack (2) 90b, and the contact 75 ₂ and the thermistor contact 82b ₂ of the battery pack (2) 90b are connected. Between them, a transfer switch (SW) 83 is connected. The negative electrode contact 75 ₃ is connected to the negative electrode contact 82b _{3 of the} battery pack (2) 90b.

Further, in the above contact 75 ₄ through the first release switch (1RSW) 85, the said contact 75 ₅ through the second release switch (2RSW) 86, it is locked switch (SW) 87 is connected to each of further and it is connected to the battery pack (1) the negative electrode for a contact 82a of 90a ₃ and the battery pack (2) the negative electrode for contact 82b ₃ of 90b.

Also, at the battery pack (1) 90a, between the contacts 82a ₁ and the contact 82a _3, a series circuit of switching element 127a and the battery cell 91a is connected, between the contact 82a ₂ and the contact 82a ₃ A thermistor 92a is connected between them. The control circuit 128a is connected so as to control the operation of the switching element 127a. Similarly, in the battery pack (2) 90b, a series circuit of a switching element 127b and a battery cell 91b is connected between the contact 82b ₁ and the contact 82b _3, and the contact 82b ₂ and the contact 82b ₃ are connected. A thermistor 92b is connected between the two. The control circuit 128b is connected so as to control the operation of the switching element 127b.

  FIG. 11 is a circuit diagram for explaining the relationship between a battery pack and a selected thermistor in a battery holder having two battery chambers.

Assume that the battery pack is not loaded in both the first battery chamber 110a and the second battery chamber 110b. In this state, the conduction of the transfer switch 83 is assumed to be switched to the second battery chamber 110b side. Then, it is assumed that the battery pack (1) 90a is loaded in a specific battery chamber which is one of the battery chambers, in this case, the first battery chamber 110a. Then, the transfer switch 83 is switched to the first battery chamber 110a side in conjunction with the battery pack (1) 90a being loaded in the first battery chamber 110a. Then, as shown in Table 1 below, the thermistor 92a in the battery pack (1) 90a is selected and becomes conductive.

  On the other hand, it is assumed that the battery pack (2) 90b is loaded only in the second battery chamber 110b, which is another battery chamber. Then, the conduction state of the transfer switch 83 is switched to the second battery chamber 110b side. Then, as shown in Table 1, the thermistor 92b in the battery pack (2) 90b is selected and becomes conductive.

  Furthermore, it is assumed that the battery packs (1) 90a and (2) 90b are loaded in the two battery chambers 110a and 110b. In this case, the transfer switch 83 is connected to the first battery chamber 110a side in conjunction with the battery pack (1) 90a being loaded in the first battery chamber 110a regardless of the state of the second battery chamber 110b. The conduction state is switched to. Therefore, even if the battery packs (1) 90a and (2) 90b are loaded in the first and second battery chambers 110a and 110b, the thermistor 92a on the battery pack (1) 90a side is selected and becomes conductive. .

  Next, the basic operation of the camera in the first embodiment will be described with reference to the flowchart of FIG.

  When a battery pack is loaded into the battery holder 80 mounted on the camera body 20, the camera is activated, and first, the initial setting by the Bμcom 65 is performed in step S1. Next, in step S2, the resistance value of the thermistor in the loaded battery pack is A / D converted. The resistance value of the thermistor is calculated in the Bμcom 65 from the pull-up resistor R11 and the resistance value of the thermistor.

For example, when the resistance R11 is 10 kΩ, the thermistor having a resistance value of 10 kΩ when the temperature is 25 ° C. and the resistance value of the thermistor when the temperature is 100 ° C. is 0.97 kΩ and 60 ° C. In this case, the resistance value is 3.02 kΩ, the resistance value at 0 ° C. is 27.28 kΩ, and the resistance value at −20 ° C. is 67.77 kΩ. And if the A / D conversion value of the resistance value of these thermistors becomes 255 when 3.3V is input, it is 22 at 100 ° C, 59 at 60 ° C, 127 at 25 ° C, 186 at 0 ° C,- It becomes 222 at 20 ° C. These A / D conversion values are used, and the thermistor is determined in steps S3 and S5.

  That is, in step S3, it is determined whether or not the A / D conversion value of the thermistor obtained in step S2 is smaller than “222”. Here, if the A / D conversion value exceeds “222”, a low temperature state where the temperature is lower than −20 ° C. or a contact failure is considered. Therefore, the process proceeds to step S4, the temperature data obtained last time is stored without using the A / D conversion value data obtained this time, and then the process proceeds to step S8. On the other hand, if it is determined in step S3 that the A / D change value is "222" or less, it is then determined in step S5 whether the A / D conversion value is greater than "59". The As a result, if the A / D conversion value is smaller than “59”, it is a high temperature of 60 ° C. or higher. Thereafter, the operation is stopped.

  If the A / D conversion value is between “222” and “59” in steps S3 and S5, the process proceeds to step S7, and the temperature is calculated from the A / D conversion value. In step S8, a determination threshold corresponding to the temperature, that is, a minimum drive voltage is calculated from the calculated temperature. Next, in step S9, the battery voltage is A / D converted from the port of Bμcom65.

  In step S10, the determination threshold obtained in step S8 is compared with the battery voltage obtained in step S9. As a result, when the battery voltage is lower than the determination threshold, the process proceeds to step S11, and a warning display indicating that the battery is not usable (is weak) because the voltage value of the loaded battery is lowered is displayed on the liquid crystal monitor. 26 etc. Thereafter, the operation is stopped.

  On the other hand, if the battery voltage is higher than the determination threshold in step S10, the charging operation is possible, so the process proceeds to step S12 and the state of the release button 21 or 121 is detected. Here, when the release button 21 or 121 is not operated (the release button is off), the process proceeds to step S2 and the above-described processing operation is repeated. On the other hand, when the release button 21 or 121 is operated (turned on), the process proceeds to step S13 and a photographing operation is performed. Thereafter, the process proceeds to step S2.

  Thus, according to the first embodiment, the temperature of the battery can be correctly measured according to the state of the battery pack to be loaded.

(Second Embodiment)
Next, a second embodiment of the present invention will be described.

  In the first embodiment described above, an example in which there are two battery chambers has been described. In the second embodiment, an example in which three battery chambers are present will be described.

  Hereinafter, the second embodiment will be described. The basic configuration of the camera is the same as that of the first embodiment shown in FIGS. 1 to 12, and the basic shooting operation is also the same. . Therefore, for these configurations and operations, the same reference numerals are assigned to the same parts, and illustration and description thereof will be omitted, and only the configurations and operations of different parts will be described.

  FIG. 13 is a circuit diagram for explaining the relationship between a battery pack and a selected thermistor in a battery holder having three battery chambers.

Of contact group 75 of the camera body 20 and the battery holder 80, the positive electrode contact 75 _1, via respective diodes D1, D2 and D3, the battery pack (1) 90a, the battery pack (2) 90b and the battery pack (3) 90c positive electrode contacts 82a ₁ , 82b ₁ and 82c ₁ are connected. Further, among the contact group 75 of the camera body 20 and the battery holder 80, the negative electrode contact 75 _3, respectively the battery pack (1) 90a, the battery pack (2) 90b and the battery pack (3) The negative electrode for a contact point 90c 82a ₃ , 82b ₃ and 82c ₃ are connected.

Furthermore, a switching terminal 83a ₁ of a transfer switch (SW) 83a is connected to the thermistor contact 75 ₂ of the contact group 75. One contact terminal 83a ₂ of the transfer switch 83a has a thermistor contact 82a ₂ of the battery pack (1) 90a, and the other contact terminal 83a ₃ has a switching terminal 83b ₁ of the transfer switch (SW) 83b. It is connected. Further, one contact terminal 83b ₂ of the transfer switch 83b has a thermistor contact 82b ₂ of the battery pack (2) 90b, and the other contact terminal 83b ₃ has a thermistor contact 82c ₂ of the battery pack (3) 90c. Is connected.

In such a configuration, the transfer switches 83a and 83b have the switching terminals 83a ₁ and 83b ₁ on the contact terminals 83a ₃ and 83b ₃ side, respectively, in a state where no battery pack is loaded in any battery chamber. It has been switched. Then, it is assumed that the battery pack (1) 90a is loaded in a specific battery chamber which is one of the battery chambers, in this case, the first battery chamber 110a. Then, regardless of the state of the second battery chamber 110b and the third battery chamber 110c, the transfer switch 83a operates in conjunction with the battery pack (1) 90a being loaded in the first battery chamber 110a. The conduction state is switched to the one battery chamber 110a side, and the thermistor 92a in the battery pack (1) 90a is selected to be in the conduction state. Similarly, when the battery pack (1) 90a is loaded in the second battery chamber 110b, the transfer switch 83b is connected to the battery pack (2 in the second battery chamber 110b regardless of the state of the third battery chamber 110c. ) In conjunction with the loading of 90b, the conduction state is switched to the second battery chamber 110b side, and the thermistor 92b in the battery pack (2) 90b is selected to become the conduction state.

  That is, when only one battery pack is loaded in the battery chamber, the thermistor of the battery pack is selected. When battery packs are loaded in a plurality of battery chambers, the battery pack is located on the upper side, in this case, the second battery pack from the third battery pack, and the first battery pack side from the second battery pack. The thermistor is selected. Therefore, when the battery packs (1) 90a to (3) 90c are loaded in all the first to third battery chambers 110a to 110c, the thermistor 92a of the first battery pack (1) 90a is selected. It will be.

  Thus, according to the second embodiment, the temperature of the battery can be correctly measured according to the state of the battery pack to be loaded.

(Third embodiment)
Next, a third embodiment of the present invention will be described.

  In the first and second embodiments described above, when a plurality of battery chambers are provided, the battery pack loaded on the upper side is used. However, in the third embodiment, a microcomputer is used. The battery pack loaded last is used.

  Hereinafter, the second embodiment will be described. The basic configuration of the camera is the same as that of the first embodiment shown in FIGS. 1 to 12, and the basic shooting operation is also the same. . Therefore, for these configurations and operations, the same reference numerals are assigned to the same parts, and illustration and description thereof will be omitted, and only the configurations and operations of different parts will be described.

  FIG. 14 shows a state of the battery holder and the battery pack according to the third embodiment of the present invention, and is a perspective view showing how the battery pack is attached to the battery holder.

  As shown in FIG. 14, battery loading switches 117 a and 117 b that are operated when the battery packs 90 a and 90 b are inserted are provided in the battery chamber 110 in the battery holder 80 ′, respectively. Since the battery loading switches 117a and 117b have the same configuration as the battery loading switch 117 described above, the description thereof is omitted here.

  FIG. 14 shows only two battery chambers and battery loading switches, but these may be provided according to the number of battery chambers.

  FIG. 15 is an external perspective view showing a configuration of a battery holder 80 ′ of a camera according to the third embodiment of the present invention. FIG. 16 shows a state when the battery holder 80 ′ is attached to the camera body 20. FIG. It is the perspective view which looked at from the camera front side lower part.

  On the lower surface of the battery holder 80, a power lever 131 that is operated corresponding to a power switch described later is provided. Reference numeral 132 denotes a release button provided on the battery holder 80 ′, which corresponds to the first release switch 85 and the second release switch 86 described above. The release button 132 functions in the same manner as the release button 21 when the battery holder 80 ′ is attached to the camera body 20.

  FIG. 17 is a schematic electric circuit diagram for explaining temperature detection of the battery pack.

  The battery holder 80 'has a microcomputer (hereinafter abbreviated as a microcomputer) 135 for detecting which of the battery chambers 110a and 110b is loaded with a battery pack. The microcomputer 135 is connected to a reset IC 136, the above-described battery loading switches 117a and 117b, and a power switch 137 corresponding to the above-described power lever 131.

Between the said contact 75 ₂ and the battery pack (1) thermistor contacts 82a ₂ of 90a, 82a ₂ of the camera body 20 are switching elements 141 and 142 respectively connected. These switch elements 141 and 142 correspond to the battery loading switches 117a and 117b, and are turned on and off by the microcomputer 135.

  Next, referring to a flowchart of FIG. 18, an operation for loading a battery in a camera according to the third embodiment of the present invention will be described.

  When a battery pack is loaded in the battery holder 80 ', the camera is activated, and initial setting is first performed by B.mu.com 65 in step S21. Next, in step S22, the state of the battery loading switch 117a which is the first detection switch is detected. Here, if the battery loading switch 117a is on, the process proceeds to step S23, and the first switch element 141 is turned on.

  On the other hand, if the battery loading switch 117a is not on in step S22, the process proceeds to step S24, and the state of the battery loading switch 117b as the second detection switch is detected. As a result, if the battery loading switch 117b is on, the process proceeds to step S25 and the second switch element 142 is turned on.

  If none of the detection switches is turned on in steps S22 and S24, and if any switch element is turned on in steps S23 and S25, the process proceeds to step S26. In step S26, it is determined whether or not the state of the first detection switch (battery loading switch) 117a has changed from off to on. Here, if the first detection switch 117a changes from OFF to ON, that is, if the battery pack (1) 90a is loaded in the first battery chamber 110a, the process proceeds to step S27. In step S27, the first switch element 141 is turned on.

  If the first detection switch 117a does not change from off to on in step S26, the process proceeds to step S28 and whether or not the state of the second detection switch (battery loading switch) 117b has changed from off to on. Is determined. If the second detection switch 117b is changed from OFF to ON, that is, if the battery pack (2) 90b is loaded in the second battery chamber 110b, the process proceeds to step S29. In step S29, the second switch element 142 is turned on.

  If neither the first detection switch 117a nor the second detection switch 117b changes from off to on in steps S26 and S28, either detection switch is turned on in step S23 or S25. This is the case. Thus, if any of the detection switches is turned on, the process proceeds to step S46.

  In step S46, the state of the power switch 137 of the battery holder 80 'is detected. Here, the process waits until the power switch 137 is turned on. If the power switch 137 is turned on, the process proceeds to step S26, and the subsequent processing operations are repeated.

  Here, the recognition of the battery pack loaded in the battery chamber will be described with reference to the timing chart of FIG. First, it is assumed that the battery pack (1) 90a is loaded in the first battery chamber 110a.

  When the power is turned on, the voltage VE rises, whereby the reset IC 135 rises and the microcomputer 135 is activated. Then, the port P1 of the microcomputer 135 is turned on by the initialization operation, the first switch element 141 is turned on, and the thermistor 92a of the battery pack (1) 90a is recognized.

  Here, when the battery pack (2) 90b is loaded into the second battery chamber 110b, the second detection switch 117b is turned on. Then, the port P2 of the microcomputer 135 is turned on and the port P1 is turned off. As a result, the second switch element 142 is turned on and the first switch element 141 is turned off, so that the microcomputer 135 recognizes from the thermistor 92a of the battery pack (1) 90a to the thermistor 92b of the battery pack (2) 90b. Switch.

  Thereafter, it is assumed that the battery pack (1) 90a is removed from the first battery chamber 110a and loaded again with the battery pack (2) 90b loaded in the second battery chamber 110b. Then, the first detection switch 117a is switched from OFF to ON, and in response to this, the port P1 of the microcomputer 135 is turned ON and the port P2 is turned OFF. As a result, the first switch element 141 is turned on and the second switch element 142 is turned off, so that the microcomputer 135 recognizes from the thermistor 92b of the battery pack (2) 90b to the thermistor 92a of the battery pack (1) 90a. Switch.

  Thus, according to the third embodiment, since the microcomputer recognizes the thermistor of the battery pack that was last loaded in the battery chamber, the battery temperature is correctly measured according to the state of the loaded battery pack. can do.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described.

  The third embodiment described above gives priority to the thermistor of the battery pack loaded in the battery chamber last, whereas this fourth embodiment is the first and second embodiments described above. Similarly, when a battery pack is loaded in a plurality of battery chambers, the thermistor on the higher battery pack side is selected.

  The configuration of the battery holder in the fourth embodiment is the same as that of the third embodiment described above, and the basic configuration of the camera is the first to third shown in FIGS. This is the same as the embodiment, and the same applies to the basic shooting operation. Therefore, in these configurations and operations, the same reference numerals are assigned to the same parts, and illustration and description thereof are omitted, and only different parts will be described.

  With reference to the flowchart of FIG. 20, the operation of loading a battery in the camera according to the fourth embodiment of the present invention will be described.

  When the battery pack is loaded in the battery holder 80 ', the camera is activated, and initial setting is first performed by Bμcom 65 in step S41. Next, in step S42, the state of the battery loading switch 117a which is the first detection switch is detected. If the battery loading switch 117a is on, the process proceeds to step S43 and the first switch element 141 is turned on.

  On the other hand, if the battery loading switch 117a is not on in step S42, the process proceeds to step S44, and the state of the battery loading switch 117b that is the second detection switch is detected. As a result, if the battery loading switch 117b is on, the process proceeds to step S45 and the second switch element 142 is turned on.

  If none of the detection switches is turned on in steps S42 and S44, and if any switch element is turned on in steps S43 and S45, the process proceeds to step S46.

  In step S30, the state of the power switch 137 of the battery holder 80 'is detected. Here, the process waits until the power switch 137 is turned on. If the power switch 137 is turned on, the process proceeds to step S42, and the subsequent processing operations are repeated.

  Thus, according to the fourth embodiment, the thermistor according to Table 1 can be selected as in the first embodiment described above.

(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described.

  In the above-described third embodiment, the example in which the microcomputer is provided in the battery holder and the battery pack loaded last is used has been described. In the fifth embodiment, an example in which the function of the low current consumption mode is further added to the microcomputer in the battery holder will be described.

  Hereinafter, the fifth embodiment will be described. The basic configuration of the camera is the same as that of the first to fourth embodiments shown in FIGS. 1 to 20, and the basic photographing operation is also described. It is the same. Therefore, for these configurations and operations, the same reference numerals are assigned to the same parts, and illustration and description thereof will be omitted, and only the configurations and operations of different parts will be described.

  FIG. 21 is a schematic electric circuit diagram for explaining temperature detection of a battery pack according to the fifth embodiment of the present invention.

In the circuit diagram of the configuration shown in FIG. 21 is different from the circuit configuration of FIG. 17 described above, the contacts 75 ₆ corresponding to the start signal line 113 is connected to port INT of the microcomputer 135 of the battery holder 80 " And a lock switch (SW) 144 is provided between the first detection switch (battery loading switch) 117a and the second detection switch (battery loading switch) 117b and the ground. Reference numeral 144 denotes a switch for fixing the battery loading switches 117a and 117b so that the battery loading switches 117a and 117b are not erroneously operated, and the other circuit configuration is the same as the circuit configuration in FIG.

  Next, with reference to a timing chart of FIG. 22, an operation of loading a battery in the camera according to the fifth embodiment of the present invention will be described. First, it is assumed that the battery pack (1) 90a is loaded in the first battery chamber 110a.

  In the present embodiment, the microcomputer 135 is activated by the activation signal from the Bμcom 65, and the others function as the low current consumption mode.

  When any operation is performed while the camera body 20 is in the sleep state, that is, in the low current consumption mode, a start signal is supplied from the Bμcom 65 to the battery holder 80 ″, and the microcomputer 135 is started to change from the low current consumption mode to the normal mode. Then, the port P1 of the microcomputer 135 is turned on by the initialization operation, the first switch element 141 is turned on, and the lock switch 144 is turned on, so that the thermistor 92a of the battery pack (1) 90a is turned on. Is recognized.

  Subsequent operations are the same as those in the third embodiment with reference to the timing chart shown in FIG. 19, and a description thereof will be omitted here.

  As described above, according to the fifth embodiment, the microcomputer recognizes the thermistor of the battery pack that is finally loaded in the battery chamber. Moreover, since the function in the low current consumption mode is added to the microcomputer in the battery holder, wasteful current consumption can be reduced.

  In the first to fifth embodiments described above, the battery packs loaded in the battery chambers in the battery holder have been described as having the same configuration. However, the present invention is not limited to this, and any thermistor can be detected. For example, it does not need to have the same configuration, such as different shapes.

  As mentioned above, although embodiment of this invention was described, in the range which does not deviate from the summary of this invention other than embodiment mentioned above, this invention can be variously modified.

BRIEF DESCRIPTION OF THE DRAWINGS It is the external appearance perspective view which shows the structure of the single-lens reflex type digital camera by the 1st Embodiment of this invention, and was seen from back. 1 is a block diagram illustrating a system configuration of a camera according to a first embodiment of the present invention. It is an external appearance perspective view of a battery pack. It is the figure which showed the discharge characteristic of the battery in a battery pack. It is the external appearance perspective view which showed the structure of the battery holder 80 of the camera which concerns on the 1st Embodiment of this invention. FIG. 6 is an external perspective view showing a state where a battery pack is attached to the battery holder of FIG. 5. 4 is a diagram showing an example of a battery loading switch 117 provided in the battery holder 80. FIG. It is an external view which shows the state at the time of attaching the battery holder 80 to the camera main body 20, Comprising: It is the perspective view seen from the camera front side lower part. It is an external view which shows the state at the time of attaching the battery holder 80 to the camera main body 20, Comprising: It is the figure seen from the back side of the camera. It is a schematic electric circuit diagram for explaining temperature detection of the battery pack according to the first embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a first embodiment of the present invention, and is a circuit diagram for explaining a relationship between a battery pack and a selected thermistor in a battery holder having two battery chambers. 4 is a flowchart for explaining basic operations of the camera according to the first embodiment of the present invention. FIG. 10 is a circuit diagram illustrating a relationship between a battery pack and a selected thermistor in a battery holder having three battery chambers according to a second embodiment of the present invention. It is the perspective view which showed the mode of the battery holder and battery pack by the 3rd Embodiment of this invention, and showed a mode that a battery pack was mounted | worn with a battery holder. It is the external appearance perspective view which showed the structure of battery holder 80 'of the camera which concerns on the 3rd Embodiment of this invention. FIG. 9 is a perspective view illustrating a state when a battery holder 80 ′ is attached to the camera body 20 as viewed from the lower front side of the camera according to the third embodiment of the present invention. FIG. 6 is a schematic electric circuit diagram for explaining temperature detection of a battery pack according to a third embodiment of the present invention. It is a flowchart explaining the battery loading operation | movement of the camera by the 3rd Embodiment of this invention. It is a timing chart explaining recognition of the battery pack loaded in the battery chamber by 3rd Embodiment. It is a flowchart explaining the battery loading operation | movement of the camera by the 4th Embodiment of this invention. FIG. 10 is a schematic electric circuit diagram for explaining temperature detection of a battery pack according to a fifth embodiment of the present invention. It is a timing chart explaining the battery loading operation | movement of the camera by the 5th Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Camera, 10 ... Lens barrel, 11 ... Shooting lens, 12 ... Diaphragm, 13 ... Lens drive mechanism, 14 ... Diaphragm drive mechanism, 15 ... Microcomputer for lens control (L [mu] com), 20 ... Camera body, 21 ... Release Buttons, 22 ... mode dial, 23 ... power switch lever, 24 ... control dial, 26 ... liquid crystal monitor, 33 ... finder, 35 ... communication connector, 40 ... reflector, 41 ... finder optical system, 43 ... image sensor for display, 44 ... Metering circuit, 48 ... AF sensor unit, 50 ... Shutter, 51 ... Imaging device, 53 ... AF sensor drive circuit, 54 ... Mirror drive mechanism, 55 ... Shutter charge mechanism, 56 ... Shutter control circuit, 59 ... Interface Circuit, 60 ... Image processing controller, 61 ... SDRAM, 62 ... FlashMemor , 63 ... Recording medium, 65 ... Microcomputer for body control (Bμcom), 67 ... Non-volatile memory (EEPROM), 68 ... LCD for operation display, 69 ... Camera operation switch (SW), 70 ... Power supply circuit, 75 ... Contact Group, 80 ... battery holder, 82a, 82b ... contact group, 85 ... first release switch (1RSW), 86 ... second release switch (2RSW), 84 ... lock switch, 90a ... battery pack (1), 90b ... battery Pack (2), 91a, 91b ... battery cell, 92a, 92b ... thermistor, 110a ... first battery chamber, 110b ... second battery chamber.

Claims (14)

In an external power supply that enables external power supply to electronic equipment,
A plurality of battery chambers each capable of loading a plurality of batteries each having a temperature detection element;
An external contact conducting to any of the temperature sensing elements of the battery;
When a battery is loaded into a specific battery chamber, which is one of the battery chambers, a battery is loaded into the specific battery chamber, regardless of whether the other battery chamber is loaded with a battery. Priority is given to connecting the temperature detection element of the battery loaded in the specific battery chamber to the external contact, the battery is not loaded in the specific battery chamber, and the battery chamber other than the specific battery chamber is not loaded. Circuit means for conducting a temperature detecting element of the battery loaded in the battery chamber to the external contact when the battery is loaded;
An external power supply device comprising:   The circuit means includes a transfer switch that switches connection between the plurality of battery chambers and the external contact in conjunction with a battery loaded in the specific battery chamber. The external power supply device according to 1.   The circuit means includes a plurality of detection switches for detecting the loading of each of the plurality of batteries, and a control for selecting one of the temperature detection elements based on an output from the plurality of detection switches and conducting the selected one to the external contact. The external power supply device according to claim 1, further comprising a CPU that performs the operation. In an external power supply that enables external power supply to electronic equipment,
A first battery chamber capable of loading a first battery having a first temperature detection element;
A second battery chamber capable of loading a second battery having a second temperature detection element;
An external contact conducting to one of the temperature detection elements;
When the first battery chamber is loaded in the first battery chamber and the second battery chamber is not loaded, the first temperature detection element and the external contact are electrically connected, and the second battery chamber is electrically connected. When the second battery is loaded in the battery chamber and the first battery chamber is not loaded, the second temperature detection element and the external contact are electrically connected to each other, and the first battery chamber Circuit means for electrically connecting the first temperature detecting element and the external contact when the first battery is loaded and the second battery is loaded in the second battery chamber;
An external power supply device comprising:   The circuit means includes a transfer switch that switches connection between one of the first and second battery chambers and the external contact in conjunction with a loaded state of the first battery. The external power supply device according to claim 4.   The circuit means includes a first detection switch for detecting loading of the first battery, a second detection switch for detecting loading of the second battery, the first detection switch, and the second detection switch. The external power supply device according to claim 4, further comprising a CPU that performs control to select one of the temperature detection elements based on an output from the detection switch and to conduct the temperature detection element to the external contact.   7. The external power supply device according to claim 1, wherein the temperature detection element is a thermistor.   The external power supply device according to any one of claims 1 to 6, wherein the external power supply device is an external power supply device for a camera. In an external power supply that enables external power supply to electronic equipment,
A plurality of battery chambers each capable of loading a plurality of batteries each having a temperature detection element;
An external contact conducting to any of the temperature sensing elements of the battery;
Of the plurality of batteries inserted into each of the plurality of battery chambers, control means for connecting the temperature detection element of the battery inserted last to the external contact;
An external power supply device comprising:   The external power supply device according to claim 9, wherein the external power supply device is an external power supply device for a camera. In an external power supply that enables external power supply to electronic equipment,
A first battery chamber capable of loading a first battery having a first temperature detection element;
A second battery chamber capable of loading a second battery having a second temperature detection element;
An external contact conducting to one of the temperature detection elements;
Control means for switching the connection between any one of the first battery chamber and the second battery chamber and the external contact in conjunction with the loading state of the first battery;
Comprising
The control means electrically connects the first temperature detecting element and the external contact when the first battery chamber is loaded with the first battery and the second battery chamber is not loaded. When the second battery is loaded in the second battery chamber and the first battery chamber is not loaded, the second temperature detection element and the external contact are electrically connected, and When the first battery is loaded in the first battery chamber and the second battery is loaded in the second battery chamber, the first temperature detection element is electrically connected to the external contact. An external power supply characterized in that   The control means includes a first detection switch for detecting loading of the first battery, a second detection switch for detecting loading of the second battery, the first detection switch, and the second detection switch. The external power supply apparatus according to claim 11, further comprising a CPU that performs control to select one of the temperature detection elements based on an output from a detection switch and to conduct to the external contact.   13. The external power supply device according to claim 11, wherein the temperature detection element is a thermistor.   13. The external power supply device according to claim 11 or 12, wherein the external power supply device is an external power supply device for a camera.

Images