Abstract:
A battery holding structure for exchangeably accommodating a battery is disclosed. The structure comprises; a battery container for exchangeably accommodating a battery therein, the container being provided with an opening through which a battery is to be taken in and out; a container cap detacheably coupled to the battery container to close the opening of the container; and a switching mechanism including a stationary contact member and a movable contact member both disposed on the battery container, the movable contact member being arranged to be actuated in response to the relative movement of the container cap with respect to the container. The switching mechanism is used, for instance, to keep a control system of a camera at its reset state during exchange of battery.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a battery holding structure adapted for use in, for instance, a camera. 
     In a camera using a battery as a power source, it is unavoidable to change a battery accommodated therein with a new one when a currently loaded battery is used up. During battery exchange, however, there is a possibility that chattering occurs between a battery and terminals of a camera. Chattering is a phenomenon in which violent voltage fluctuation is seen at the contacts of a battery and terminals accompanying the rapid alteration of continuity and discontinuity of current having a period of μ sec order. This may cause in a camera employing a CPU (Central Processing Unit) for controlling its operation, a CPU to run away due to chatterings to cause electric malfunctions such as improper initializations of a CPU. 
     SUMMARY OF THE INVENTION 
     It is therefore the object of the present invention to provide a battery holding structure adapted for use in, for instance, a camera, capable of preventing occurrence of electric malfunction due to chatterings during battery exchange. 
     According to one aspect of the present invention there is provided a battery holding structure for exchangeably accommodating a battery therein which comprises: 
     a battery container for exchangeably accommodating a battery therein, the container being provided with an opening through which a battery is to be taken in and out; 
     a container cap detacheably coupled to the battery container to close the opening of the container; and 
     a switching mechanism including a stationary contact member and a movable contact member both disposed on the battery container, the movable contact member being arranged to be actuated in response to the relative movement of the container cap with respect to the container. 
     With the above constituted container, the switching mechanism is operated when battery exchange is carried out as the container cap is moved relative to the container. 
     In a preferred embodiment of the invention, the container cap comprises a screw-type container cap to be threaded to the battery container. 
     In one embodiment of the invention, the battery container comprises a fitting member fixed in front of the opening, the fitting member being formed with a center hole corresponding to the opening and provided with an inner thread on the inner circumferential surface of the center hole; and the container cap is provided with a center boss having an external thread on the outer circumferential surface thereof to be screwed to the inner thread of the fitting member. 
     Further, the container is provided with a sleeve member to be slidably accommodated in the battery container, the sleeve member being detacheably coupled to the container cap at one end thereof to accomodate a battery therein with the upper portion of the battery being protruded from the other end of the sleeve member; and the battery container comprises an inner wall member in which a battery is accommodated together with the sleeve member. 
     On the inner wall member, a through-hole is formed at the position where the other end of the sleeve member reaches when the sleeve member is fully introduced into the container; and the stationary contact member is fixed on the outer surface of the inner wall member, while the movable contact member is provided with a free end portion which is biased to go beyond the inner wall member via the through-hole. The free end of the movable contact member is pressed against the biasing force by the outer surface of the sleeve member when the sleeve member is fully introduced into the container. 
     Preferably, the movable contact member is made of an elastic material and is normally forced to contact the stationary member by its elasticity, and is detached from the stationary member when the free end is pressed outwardly by the sleeve member. 
     In other embodiment of the present invention, the stationary contact member is fixed on the inner surface of said fitting member, while the movable contact member is provided with a free end portion which is arranged to contact the stationary contact member, the free end portion being formed to be pressed by the container cap when the container cap is screwed to the fitting member. 
     Preferably, the movable contact member is made of an elastic material and is normally forced to contact the stationary member by its elasticity, and is detached from the stationary member when the free end portion is pressed by the container cap. 
     In other aspect of the present invention, a battery holding structure is applied to a camera employing a battery as a power source for electronically operating a control system of the camera, wherein the operation of the control system is suspended during exchange of battery as the switching mechanism is correspondingly operated. For instance, the switching mechanism is connected to a reset terminal of the control system to keep the control system at its reset state during exchange of battery. 
     Preferably, the control system is kept at its reset state while the movable contact member is being detached from the stationary contact member. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a camera employing a battery holding structure embodying the invention; 
     FIGS. 2 &amp; 3 are fragmentary cross-sectional views showing a battery holding structure of FIG. 1; 
     FIGS. 4A &amp; 5A are fragmentary cross-sectional views showing another battery holding structure of FIG. 1; 
     FIGS. 4B &amp; 5B are partial cross-sectional views of a different section than FIGS. 4A &amp; 5A, respectively; and 
     FIG. 4C is a schematic right side view of FIG.  4 A. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 is a perspective view of a compact camera  10  having a battery container unit  100  at the upper left side thereof. 
     [First Embodiment] 
     FIG.  2  and FIG. 3 are fragmentary cross-sectional views of the battery container unit  100  shown in FIG.  1 . As shown in FIG. 2, the battery container unit  100  accommodates a battery  9  in a battery compartment  3 B formed therein. The battery compartment  3 B is defined by a container frame  101 , a battery compartment wall  31 , a fitting plate  7 B disposed between the frame  101  and the wall  31 , and a screw-type battery container cap  2 B detacheably screwed to the fitting plate  7 B. Further, a battery holding sleeve  6  is provided as an intermediate member to be disposed between the wall  31  and the battery  9 . 
     The container frame  101  and the wall  31  are made of a non-conductive material such as a plastic resin to prevent short circuit between a battery  9  and other members of the camera  10 . 
     On the other hand, the fitting plate  7 B is made of a conductive material such as a metal and fixed to the frame  101  and the wall  31  by means of a fastening member like a screw, not shown. The fitting plate  7 B is provided with a center circular opening  75  having an internal thread  71  formed on the inner peripheral surface thereof. The fitting plate  7 B is electrically connected to a ground terminal of an electric circuit, not shown, of the camera  10 . 
     The container cap  2 B is generally formed in a disc-like shape having a larger diameter than that of the center circular opening  75  of the fitting plate  7 B, and a linear center groove  23  is formed on the outer surface  27 , i.e., the surface facing outward when screwed to the container unit  100 , of the cap  2 B. 
     A circular rib  24  having the outer diameter substantially corresponding to the diameter of the center opening  75  of the fitting plate  7 B is protruded from the inner surface, i.e., the surface facing inside the compartment  3 B when screwed to the container unit  100 , of the cap  2 B. An external thread  24   a  is formed on the outer circumferential surface of the rib  24  to be meshed with the internal thread  71  of the fitting plate  7 B. When the cap  2 B is fully screwed into the compartment  3 B with the external thread  24   a  of the rib  24  being engaged with the internal thread  71  of the fitting plate  7 B, the battery compartment  3 B is thereby completely closed. 
     A center columnar boss  26  having a larger height than that of the circular rib  24  is formed on the inner surface of the cap  2 B such that the top surface  26   a  of the boss  26  is forced to contact a negative terminal  16  of a battery  9  accommodated in the battery compartment  3 B when the cap  2 B is screwed into the compartment  3 B. 
     The center columnar boss  26 , the circular rib  24  and the connecting portions therebetween of the inner surface of the cap  2 B are made of a conductive material such as a metal, thereby the negative terminal  16  of a battery  9  is electrically connected to the fitting plate  7 B when the cap  2 B is screwed into the compartment  3 B. 
     The intermediate battery holding sleeve  6  is formed as a cylindrical member by a non-conductive material such as a plastic resin. The outer diameter of the holding sleeve  6  is so set as to be coaxially and relatively slidably fitted into the wall  31 , while the inner diameter and the height thereof are so set as to fixedly accomodate a substantially half portion of a battery  9  therein. One end (the leftmost end in FIG. 2) of the holding sleeve  6  is formed as a smaller diameter circular portion  9   a  to be relatively rotatably interfitted with the circular rib  24  of the cap  2 B, thereby the holding sleeve  6  is detacheably coupled to the cap  2 B. 
     It should be noted that, as the sleeve  6  is relatively rotatably coupled to the cap  2 B, the rotation of the cap  2 B is not obstructed even if friction is caused between the sleeve  6  and the inner surface of the wall  31 . 
     At the center of the innermost end of the battery compartment wall  31 , provided is a leaf-spring electric terminal  39  arranged to resiliently contact a positive terminal  92  of a battery  9  when a battery  9  is inserted into the battery compartment  3 B. 
     On the outer surface of the battery compartment wall  31 , arranged is a switch mechanism  1 B consisted of a switching arm  4 B and a switching plate  5 B. 
     The switching arm  4 B is made of an elastic conductive material such as a metal, and secured at the intermediate portion thereof to a mounting boss  33  formed on the outer surface of the wall  31  by means of a fastening screw  34 . The arm  4 B is biased toward the outer surface of the wall  31  by means of elasticity thereof. The front end of the arm  4 B is vent to form a substantially V-shaped hook  41 B which is to be introduced into the battery compartment  3 B via a later-described through-opening  32  of the wall  31 . At the portion between the hook  41 B and the mounting boss  33  on the inner surface of the arm  4 B, a point contact  42  is formed to face the outer surface of the wall  31 . The tail end of the arm  4 B, not shown, is electrically connected to a reset terminal of a CPU, not shown, of the camera  10 . 
     The switching plate  5 B is made of a conductive material such as a metal and fixed to the outer surface of the wall  31  at the position facing to the point contact  42  of the switching arm  4 B. As the arm  4 B is biased toward the wall  31 , the point contact  42  is urged to contact the switching plate  5 B. The switching plate  5 B is, on the other hand, electrically connected to a ground terminal of an electric circuit, not shown, of the camera  10  via the fitting plate  7 B. 
     The V-shaped hook  41 B is formed such that, under the state illustrated in FIG. 2 in which the holding sleeve  6  contacts the hook  41 B just inside the through-opening  32  of the wall  31 , the hook  41 B is forced to be out of the battery compartment  3 B by the holding sleeve  6  against the elasticity of the switching arm  4 B, so that the point contact  42  of the arm  4 B is detached from the switching plate  5 B fixed to the outer surface of the wall  31 . On the contrary, under the state illustrated in FIG. 3 in which the holding sleeve  6  does not exist, the point contact  42  is forced to contact the switching plate  5 B by the elasticity of the switching arm  4 B. 
     The inside of the battery compartment wall  31  is divided into a larger diameter portion  31   a  and a smaller diameter portion  31   b  in the direction along which a battery  9  is inserted thereinto. The larger diameter portion  31   a  is formed to be able to accomodate the battery holding sleeve  6  together with a battery  9 , while the smaller diameter portion  31   b  is formed to be able to accomodate only the front half portion of a battery  9  protruded out of the holding sleeve  6 . At the innermost side of the larger diameter portion  31   a  of the wall  31 , the above-mentioned through-opening  32  is formed. 
     Hereafter, a battery exchange in the above constituted battery holding structure will be explained exemplifying the case in which an old battery accommodated in the battery container unit  100  is replaced with a new battery. 
     First of all, a coin or the like is fitted in the center groove  23  on the outer surface of the container cap  2 B, and rotated in a clockwise-direction to unscrew the container cap  2 B from the fitting plate  7 B. 
     When the cap  2 B is rotated by a certain amount, the battery holding sleeve  6  which is coupled to the cap  2 B is moved to the position illustrated in FIG. 3, where the V-shaped hook  41 B is allowed to enter into the battery compartment  3 B and the point contact  42  comes into contact with the switching plate  5 B. 
     With further rotating the cap  2 B, the external thread  24   a  of the circular rib  24  of the cap  2 B is completely disengaged from the internal thread  71  of the fitting plate  7 B. Thus, the cap  2 B can be separated from the camera  10  together with the battery holding sleeve  6 , and a currently loaded battery  9  is taken out of the container unit  100 . 
     Then, a new battery  9  to be loaded is placed in the holding sleeve  6  coupled to the cap  2 B, with the positive terminal thereof facing outward, and is inserted into the battery compartment  3 B together with the holding sleeve  6  coupled to the cap  2 B. When the cap  2 B and the holding sleeve  6  are blocked by the fitting plate  7 B to further approach into the battery compartment  3 B, the cap  2 B is rotated counter-clockwise direction by a coin or the like so that the external thread  24   a  of the circular rib  24  of the cap  2 B is screwed with the internal thread  71  of the fitting plate  7 B. 
     In the meantime, when the battery holding sleeve  6  is inserted into the compartment  3 B beyond the position illustrated in FIG. 3, the innermost and of the holding sleeve  6  comes into contact with the slant portion  43  of the V-shaped hook  41 B and to force the hook  41  to be moved outwardly against the elasticity of the switching arm  4 B. 
     When the external thread  24   a  of the circular rib  24  of the cap  2 B is completely meshed with the internal thread  71  of the fitting plate  7 B as illustrated in FIG. 2, a new battery  9  is firmly located between the leaf-spring electric terminal  39  and the top surface  26   a  of the boss  26  of the cap  2 B in the battery compartment  3 B. Further, the point contact  42  of the switching arm  4 B is kept away from the switching plate  5 B as the V-shaped hook  41 B of the switching arm  4 B is prevented to enter into the battery compartment  3 B by means of the outer surface of the holding sleeve  6 . 
     According to the above explained battery holding structure in a camera embodying the invention, the switching mechanism  1 B is being turned ON during the substantial period of the battery exchange in the camera  10 , which causes a CPU, not shown, of the camera  10  to be kept in a RESET state. 
     More particularly, under the normal condition illustrated in FIG. 2 wherein a battery  9  is completely loaded in the battery compartment  3 B to function as a power source for electrically operating the camera  10 , the battery holding sleeve  6  exists right inside the through-opening  32  of the battery container wall  31 , which prevents the V-shaped hook  41 B of the switching arm  4 B to enter into the battery compartment  3 B, thereby the point contact  42  of the switching arm  4 B being detached from the switching plate  5 B, i.e., the switching mechanism  1 B is being turned OFF. 
     On the other hand, at the initial stage of the battery exchange, the innermost end of the battery holding sleeve  6  is moved toward left in FIG. 2 with the initial-state rotation of the container cap  2 B and out of contact from the V-shaped hook  41 B as illustrated in FIG.  3 . Under this condition, the V-shaped hook  41 B is allowed to enter into the battery compartment  3 B and the point contact  42  of the switching arm  4 B is forced to be in contact with the switching plate  5 B by the elasticity of the switching arm  4 B, i.e., the switching mechanism  1 B is being turned ON. This ON state of the switching mechanism  1 B is kept until the innermost end of the battery holding sleeve  6  is again inserted into the battery compartment  3  together with a new battery  9  and brought into contact with the V-shaped hook  41  at the last stage of the battery exchange, to force it to be moved out of the battery compartment  3 B against the elasticity of the switching arm  4 B. 
     Thus, even though a battery  9  may insecurely keep or intermittently restore the contact with the leaf-spring terminal  39  and the top surface  26   a  of the boss  26 , after the initial stage or before the last stage of battery exchange (i.e., after or before the stage illustrated in FIG.  3 ), the operations by a CPU, not shown, of the camera  10  is not influenced at all as a CPU is kept at its RESET state by the switching mechanism  1 B during battery exchange. 
     [Second Embodiment] 
     FIG.  4 A and FIG. 5A are fragmentary cross-sectional views of the second embodiment of the battery container unit  100  shown in FIG.  1 . 
     As shown in FIG. 4A, the battery container unit  100  accommodates a battery  9  in a battery compartment  3 A formed therein. The battery compartment  3 A is defined by a container frame  101 , a battery compartment wall  31 A, a fitting plate  7 A disposed between the frame  101  and the wall  31 A, and a screw-type battery container cap  2 A detacheably screwed to the fitting plate  7 A. The container frame  101  and the wall  31 A are made of a non-conductive material such as a plastic resin to prevent short circuit between a battery  9  and other members of the camera  10 . 
     On the other hand, the fitting plate  7 A is made of a conductive material such as a metal and fixed to the frame  101  and the wall  31 A by means of a fastening member like a screw, not shown. The fitting plate  7 A is provided with a center circular opening  75  having an internal thread  71  formed on the inner peripheral surface thereof. The fitting plate  7 A is electrically connected to a ground terminal of an electric circuit, not shown, of the camera  10 . 
     The container cap  2 A is generally formed in a disc-like shape having a larger diameter than that of the center circular opening  75  of the fitting plate  7 A, and a linear center groove  23  is formed on the outer surface  27  thereof. 
     A center columnar boss  24 A having the outer diameter substantially corresponding to the diameter of the center opening  75  of the fitting plate  7 A is inwardly protruded from the inner surface of the cap  2 A. An external thread  24 A a  is formed on the outer circumferential surface of the boss  24 A to be meshed with the internal thread  71  of the fitting plate  7 A. When the cap  2 A is fully screwed into the compartment  3 A with the external thread  24 A a  of the boss  24 A being engaged with the internal thread  71  of the fitting plate  7 B, the battery compartment  3 B is thereby completely closed. 
     A center circular rib  26 A is formed on the inner surface of the columnar boss  24 A such that the top surface of the rib  26 A is forced to contact a negative terminal  16  of a battery  9  accommodated in the battery compartment  3 A when the cap  2 A is screwed into the compartment  3 A. 
     The center columnar boss  24 A, the circular rib  26 A and the connecting portions therebetween of the inner surface of the cap  2 A are made of a conductive material such as a metal, thereby the negative terminal  16  of a battery  9  is electrically connected to the fitting plate  7 A when the cap  2 A is screwed into the compartment  3 A. 
     On the inner circumferential surface of the fitting plate  7 A, arranged is a switch mechanism  1 A consisted of a switching arm  4 A and a switching plate  5 A. 
     The switching arm  4 A is made of an elastic conductive material such as a metal, and secured at the base end thereof to a mounting platform  73  which is made of a non-conductive material such as a plastic resin. The mounting platform  73  is provided with a pair of bosses  73 A,  73 A and another pair of bosses  73 B,  73 B, vertically protruded therefrom. The pair of bosses  73 A,  73 A are for positioning the switching arm  4 A with respect to the platform  73 , while the another pair of  73 B,  73 B are for positioning the platform  73  itself with respect to the fitting plate  7 A. The mounting platform  73  is fixed to the fitting plate  7 A by means of a fastening screw  76  through an opening  73 C with sandwiching the base end of the switching arm  4 A between the screw head of the fastening screw  76  and the mounting platform  73 . The screw  76  is made of a conductive material such as a metal, and therefore the switching arm  4 A is electrically connected to a reset terminal of a CPU, not shown, of the camera  10  via the screw  76  and the fitting plate  7 A. The front free end of the arm  4 A is formed as a hook portion  41 A having a substantially U-shaped sectional configuration, and is biased toward the fitting plate  7 A (leftwardly in FIGS. 4A &amp; 4B) by means of elasticity of the switching arm  4 A itself. 
     The switching plate  5 A is made of a conductive material such as a metal, and fixed to the inner surface of the fitting plate  7 A via an insulating plate  72  made of a non-conductive material such as a plastic resin to prevent short-circuit between the switching plate SA and the fitting plate  7 A. The switching plate  5 A is further provided with a lug  51  to be electrically connected to a ground terminal of an electric circuit, not shown, of the camera  10  via a connecting cable, not shown. 
     The switching plate  5 A and the insulating plate  72  are formed with openings  5 A a  and  72 A, respectively, through which the fastening screw  76  passes, but short-circuit between the conductive screw  76  and the switching plate  5 A is prevented by an insulating layer formed around the periphery of the opening  5 A a  of the plate  5 A. 
     The U-shaped hook portion  41 A is formed to extend toward the center opening  75  of the fitting plate  7 A to such an extent that, under the state illustrated in FIG. 4B in which the container cap  2 A is completely fastened to the fitting plate  7 A, the hook portion  41 A is pressed and moved by the peripheral edge of the inner surface of the cap  2 A toward inside the battery compartment  3 A against the elasticity of the switching arm  4 A, while, under the state illustrated in FIG. 5A in which the inner surface of the cap  2 A does not press the hook portion  41 A, it is forced to touch the switching plate  5 B fixed to the fitting plate  7 A by the elasticity of the arm  4 A. 
     Hereafter, a battery exchange in the above constituted battery holding structure will be explained exemplifying the case in which an old battery accommodated in the battery container unit  100  is replaced with a new battery. 
     First of all, a coin or the like is fitted in the center groove  23  on the outer surface of the container cap  2 A, and rotated in a clockwise-direction to unscrew the container cap  2 A from the fitting plate  7 A. 
     When the cap  2 A is rotated by a certain amount, the cap  2  is moved to the position illustrated in FIG. 5B, where the U-shaped hook portion  41 A is not pressed by the cap  2 A and comes into contact with the switching plate  5 A. 
     With further rotating the cap  2 A, the external thread  24 A a  of the center boss  24 A of the cap  2 A is completely disengaged from the internal thread  71  of the fitting plate  7 A. Thus, the cap  2 A can be separated from the camera  10 , and a currently loaded battery  9  is taken out of the container unit  100 . 
     Then, a new battery  9  is inserted into the battery compartment  3 A and then the container cap  2 A is pushed toward the center opening  75  of the fitting plate  7 A and rotated counter-clockwise direction by a coin or the like so that the external thread  24 A a  of the center boss  24 A of the cap  2 A is screwed with the internal thread  71  of the fitting plate  7 A. 
     In the meantime, when the cap  2 A is inserted into the compartment  3 A by a certain amount, i.e., beyond the position illustrated in FIG. 5A, it becomes in contact with the U-shaped hook portion  41 A, and presses it to be moved inwardly against the elasticity of the switching arm  4 A. 
     When the external thread  24 A a  of the center boss  24 A of the cap  2 A is completely meshed with the internal thread  71  of the fitting plate  7 A as illustrated in FIG. 4A, a new battery  9  is firmly located between the leaf-spring electric terminal  39  and the top surface  26   a  of the circular rib  26  of the cap  2 A in the battery compartment  3 A. Further, the U-shaped hook portion  41 A of the switching arm  4 A is kept away from the switching plate  5 A by means of the inner peripheral surface of the container cap  2 A. 
     According to the above explained battery holding structure in a camera embodying the invention, the switching mechanism  1 A is being turned ON during the substantial period of the battery exchange in the camera  10 , which causes a. CPU, not shown, of the camera  10  to be kept in a RESET state. 
     More particularly, under the normal condition illustrated in FIG. 4B wherein a battery  9  is completely loaded in the battery compartment  3 A to function as a power source for electrically operating the camera  10 , the inner peripheral surface of the container cap  2 A prevents the U-shaped hook portion  41 A of the switching arm  4 A to contact the switching plate  5 A, so that the switching mechanism  1 A is turned OFF. 
     On the other hand, at the initial stage of the battery exchange, the container cap  2 A is moved toward left in FIG.  4 B and the U-shaped hook portion  41 A is allowed to be in contact with the switching plate  5  by the elasticity of the switching arm  4 A, as illustrated in FIG. 5B, so that the switching mechanism  1 A is turned ON. This ON state of the switching mechanism  1 A is kept until the inner peripheral surface of the container cap  2 A is again inserted into the battery compartment  3  and brought into contact with the U-shaped hook portion  41 A at the last stage of the battery exchange, to force it to be moved inwardly against the elasticity of the switching arm  4 A. 
     Thus, even though a battery  9  may insecurely keep or intermittently restore the contact with the leaf-spring terminal  39  and the top surface  26 A a  of the rib  26 , after the initial stage or before the last stage of battery exchange, the operations by a CPU, not shown, of the camera  10  is not influenced at all as a CPU is kept at its RESET state by the switching mechanism  1 A during battery exchange. 
     As above described, in accordance with the battery holding structure in a camera embodying the invention, a CPU is kept at its RESET state during the substantial period of battery exchange, so that a CPU does not run away if chatterings or the like occur during battery exchange, and a camera can be properly operated after replacement of accommodated battery. 
     The present disclosure relates to subject matter contained in Japanese Patent Application No. HEI 10-280148, filed on Oct. 1, 1998, which is expressly incorporated herein by reference in its entirety.