Abstract:
An electronic apparatus comprises a battery pack that comprising a first battery cell and a second battery cell that are arranged in a first direction and store energy for enabling operation of electronic components; and a battery holder that houses the battery pack. The battery holder comprises a projecting part in a first face that configures the battery holder and covers the battery pack while the battery pack is provided with a slit that is fitted with the projecting part in a second face that is opposed to the first face. Furthermore, the first direction intersects a boundary direction extending between the first battery cell and the second battery cell, and the slit is formed to extend along the first direction in the second face.

Description:
CROSS-REFERENCE TO THE RELATED APPLICATION(S) 
     This application is a continuation application that is based upon and claims priority to U.S. application Ser. No. 12/898,348, now abandoned, which is based upon and claims priority from prior Japanese Patent Application No. 2010-019684, filed on Jan. 29, 2010, the entire contents of which are incorporated herein by reference. 
    
    
     FIELD 
     Embodiments described herein generally relate to a battery pack and an electronic apparatus which houses a battery pack. 
     BACKGROUND 
     In recent years, it has become a common procedure for a user to carry a portable information terminal such as a notebook personal computer. On the other hand, it has been proposed to install a TV receiver in a wall-hung manner rather than a stationary manner. Such electronic apparatus are strongly required by users to be reduced in size, weight, or thickness. However, to reduce the size, weight, or thickness of an electronic apparatus, the strength of the case of the electronic apparatus should be increased. 
     For example, JP-A-2005-275123 discloses an electronic apparatus having a display panel in which the display panel is reinforced and held by holding members in which lightweight, first to third reinforcement structures (beams) are formed at a low cost by pressing. 
     Another document, JP-A-2006-260255, discloses an electronic apparatus in which a case of a battery unit has a thin portion that is thinner than its battery cell housing portion. The battery unit is disposed in such a manner that the thin portion and a pointing device are arranged in the thickness direction of the electronic apparatus so as to overlap with each other. 
     However, JP-A-2005-275123 only intends to increase the productivity by decreasing the number of working steps for producing the holding members and to reinforce the display panel with the holding members. No consideration is given to influence of interference between the projected faces of the reinforcement beams and other members. 
     To reduce the thickness of the electronic apparatus, JP-A-2006-206255 merely employs the structure that the case of the battery unit is made thin in the thickness direction of the electronic apparatus in the region where the battery unit overlaps with the pointing device. Therefore, no consideration is given to increasing the strength of the thickness-reduced portion of the case of the electronic apparatus main body. 
     That is, conventionally, an electronic apparatus may be difficult to be made thinner while the strength of the case of the electronic apparatus main body is increased. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A general configuration that implements the various features of the present invention will be described with reference to the drawings. The drawings and the associated descriptions are provided to illustrate embodiments of the invention and not to limit the scope of the invention. 
         FIG. 1  is a perspective view of a notebook personal computer (PC) (electronic apparatus) according to an embodiment of the present invention. 
         FIG. 2  is a bottom plan view of a main unit of the notebook PC. 
         FIG. 3  is a top perspective view of a battery pack. 
         FIG. 4  is a partial sectional view, taken along line IV-IV in  FIG. 3 , of part of the battery pack, wherein the line IV-IV is line drawn so as not to coincide with a slit extending in the X direction. 
         FIG. 5  is a sectional view, taken along line IV-IV in FIG.  3 , of part of the battery pack. 
         FIG. 6  is a sectional view, taken along line VI-VI in  FIG. 3 , of part of the battery pack, wherein the line VI-VI is a line drawn so as not to coincide with either of slits extending in the Y direction. 
         FIG. 7  is a partial sectional view taken by a plane that intersects a beam, extending in the X direction, of the main unit (and the slit extending in the X direction) in the state that the battery pack is housed in a battery holder. 
         FIG. 8  is a top view of the battery pack. 
     
    
    
     DETAILED DESCRIPTION 
     According to the embodiments described herein, there is provided an electronic apparatus including: an electronic component; a battery pack configured to supply power to the electronic component; and a battery holder configured to receive the battery pack, wherein a first face of the battery holder opposing to a second face of an outside wall of the battery pack is formed to comprise a beam, and wherein the second face of the battery pack is formed to include a slit that is fitted with the beam. 
     Embodiments according to the present invention will be described in detail with reference to the accompanying drawings. The scope of the claimed invention should not be limited to the examples illustrated in the drawings and those described in below. 
       FIG. 1  is a perspective view of a notebook personal computer (PC)  1  (electronic apparatus) according to the embodiment of the invention. 
     As shown in  FIG. 1 , the notebook PC  1  according to the embodiment is composed of a main unit  2  which is provided with a keyboard  5  etc. and a display unit  3  which is provided with a display panel  6  etc. The display unit  3  is attached to the main body  2  so as to be opened and closed. 
     The following directions are defined in this description for a state that the notebook PC  1  is in use. The X direction is defined as the width direction of the main unit  2  (right-left direction), the Y direction is defined as the depth direction of the main unit  2  as viewed from the user (front-rear direction), and the Z direction is defined as the thickness direction of the main unit  2  (top-bottom direction). The X, Y, and Z directions are perpendicular to each other. In each of the following drawings of components, directions written therein indicate how the components are oriented in the notebook PC  1 . In the following description, the front side and the rear side are defined as the user&#39;s side and the deep side, respectively, in the depth direction (Y direction). The top side and the bottom side are defined as the front face side and the back face side in the thickness direction (Z direction). 
     Although the embodiment is directed to the notebook PC  1  as an example electronic apparatus according the invention, the invention may also be applied to other electronic apparatus such as a portable mobile terminal device and a cell phone. 
     The main unit  2  has a rectangular, thin case  2   a  and the display unit  3  has a rectangular, thin case  3   a . The cases  2   a  and  3   a  may be made of a metal material, a synthetic resin material, or the like. 
     A keyboard  5 , a pointing device  7 , and click buttons  8  (manipulation input units), and other components are provided in the main unit  2  so as to be exposed in a front face  2   b  (outer face) of the case  2   a . Only keys  5   a  which are part of the keys of the keyboard  5  are shown in  FIG. 1 . The case  2   a  has a ceiling wall  2   j  and a palm rest  2   k  on the rear side and the front side, respectively. 
     The main unit  2  is provided with a battery holder  9  for housing a battery pack  10  which is a component (module) to be described later in detail with reference to  FIG. 3 . The battery pack  10  is housed in the battery holder  9  by inserting the former from below. The battery holder  9  is disposed under the ceiling wall  2   j . Alternatively, the battery holder  9  may be disposed under the palm rest  2   k.    
     The main unit  2  is an apparatus main body which is equipped with such electronic components as an HDD, a main board, a wireless communication module, etc. (none of them are shown). 
     The display unit  3  is equipped with the display panel (a display device having a display screen)  6  such as an LCD (liquid crystal display) panel as an electronic component in such a manner that it is exposed in a face (outer face)  3   b  of the case  3   a.    
     Hinge mechanisms  4  connect end portions of the main unit  2  and an end portion of the display unit  3  so that they can rotate with respect to each other. The hinge mechanisms  4  allow the main unit  2  and the display unit  3  to rotate with respect to each other about a rotation axis Ax between an open state and a closed state.  FIG. 1  shows the open state. In the open state, the keyboard  5 , the display panel  6 , etc. are exposed and the user can use them. In the closed state, the faces  2   b  and  3   b  are close to and opposed to each other and the keyboard  5 , the display panel  6 , etc. are hidden by the cases  2   a  and  3   a.    
     Plural electronic components provided in the main unit  2  and the display unit  3  operate being supplied with power from the battery pack  10  which is housed in the battery holder  9 . 
     Next, the structure of a bottom face  2   e  of the main unit  2  of the notebook PC  1  will be described with reference to  FIG. 2 .  FIG. 2  is a bottom plan view of the main unit  2  of the notebook PC  1 . 
     The bottom face  2   e  (outer face) of the case  2   a  of the main unit  2  is formed with the battery holder  9  for housing the battery pack  10  at a rear end position that is close to a rear face  2   d  of a rear side wall (part of the circumferential wall) of the case  2   a . The battery holder  9  has a long and narrow, generally rectangular-parallelepiped-shaped space extending in the X direction parallel with the rear face  2   d . The battery holder  9  is a concave recess formed in a bottom wall  2   c  which has the bottom face  2   e.    
     The battery pack  10 , which will be described later in detail with reference to  FIG. 3 , is housed in the battery holder  9 . The battery holder  9  is provided with a connector  2   f  having terminals to be electrically connected to the battery pack  10  housed in the battery holder  9 . In the state that the battery pack  10  is housed in the battery holder  9 , a bottom face  10   b  of the battery pack  10  and the bottom face  2   e  form a continuous surface. That is, the bottom face  10   b  of the battery pack  10  serves as a lid of the battery holder  9 . 
     An XY cross section, a YZ cross section, and a ZX cross section of the battery holder  9  conform to a corresponding XY cross section, YZ cross section, and ZX cross section of the battery pack  10 , respectively. In the embodiment, a top wall  9   a  of the battery holder  9  (part of the case  2   a ) is formed with a beam  50  extending in the X direction and beams  51  and  52  extending in the Y direction. The beams  50 - 52  project downward from the outer face of the top wall  9   a . The top wall  9   a  is shaped so as to conform to the confronting outer face of the battery pack  10  in the state that the battery pack  10  is housed in the battery holder  9 . The top wall  9   a  which is part of the case  2   a  is increased in strength (reinforced) by the beams  50 - 52 . 
     Next, the outward form of the battery pack  10  will be described with reference to  FIG. 3 .  FIG. 3  is atop perspective view of the battery pack  10 . 
     The battery pack  10  is a component that stores electric energy for enabling operation of the plural electronic components provided in the main unit  2  and the display unit  3 . The battery pack  10  is equipped with battery cells (batteries) which function as power sources. 
     The battery pack  10  is provided with a connector  10   c  having terminals for supplying power from the battery pack  10  to the electronic components etc. of the notebook PC  1 . The terminals of the connector  10   c  are also used for charging up the batteries of the battery pack  10 . In the state that the battery pack  10  is housed in the battery holder  9 , the terminals of the connector  10   c  are electrically connected to those of the connector  2   f  of the battery holder  9 . 
     Nails  10   d  to be engaged with the case  2   a  are formed on the bottom-front edge of the battery pack  10 , and the rear face of the battery pack  10  is formed with ribs  11 . The state that the battery pack  10  is housed in the battery holder  9  is maintained by the nails  10   d  and the ribs  11 . 
     The battery pack  10  is generally shaped like a long and narrow, rectangular parallelepiped extending in the X direction. The bottom face  10   b  of the battery pack  10  is generally flat, and the bottom face  10   b  and the bottom face  2   e  of the case  2   a  form a continuous surface in the state that the battery pack  10  is housed in the battery holder  9 . A YZ cross section of the top face  10   a  of the battery pack  10  projects upward and has an inverted-U shape based, in part, on a curvature of a portion  50   b  of top surface  10   a . To conform to this shape, a corresponding YZ cross section of the top wall  9   a  of the battery holder  9  also has an inverted-U shape. 
     The top face  10   a  (a face of the outside wall) of the battery pack  10  is formed with a slit  60  extending in the X direction and slits  61  and  62  extending in the Y direction. The slits  60 - 62  are grooves which are recessed downward from the top face  10   a . In the state that the battery pack  10  is housed in the battery holder  9 , the slits  60 - 62  are fitted with the respective beams  50 - 52  of the top wall  9   a , opposed to the top face  10   a , of the battery holder  9 . This structure can minimize the gap in the Z direction between the battery holder  9  and the battery pack  10  in the state that the battery pack  10  is housed in the battery holder  9 . 
     The battery pack  10  incorporates the plural battery cells (batteries) for storing electric energy. Details will be described with reference to  FIGS. 4-6  and  8 . 
     The internal structure of the battery pack  10  will be described with reference to  FIGS. 4 and 5 . Each of  FIGS. 4 and 5  is a sectional view, taken along line IV-IV in  FIG. 3 , of part of the battery pack  10  (line IV-IV is drawn so as not to coincide with the slit  60 ). 
     As shown in  FIG. 4 , the top face  10   a  of the battery pack  10  is formed with the slits  61  and  62 . A partition wall  10   k  is erected from the bottom face  10   b  of the battery pack  10  toward the bottom wall of the slit  61 . The partition wall  10   k  is a member for partitioning the space where battery cells  500   a  and  500   b  are placed. It is obligatory to partition the space where the battery cells  500   a  and  500   b  are placed in constructing the battery pack  10 . In the embodiment, the battery cells  500   a  and  500   b  are cylindrical cells. The battery cells  500   a  and  500   b  are thus disposed on both sides of the partition wall  10   k.    
     The negative terminal side of the battery cell  500   a  is disposed on the left of the partition wall  10   k  and has a negative terminal  501 . The negative terminal  501  is in contact with a negative electrode  503  which is one of electrodes for electrical connections between the plural battery cells incorporated in the battery pack  10 . 
     The positive terminal side of the battery cell  500   b  is disposed on the right of the partition wall  10   k  and has a positive terminal  502 . The positive terminal  502  is in contact with a positive electrode  504  which is one of the electrodes for electrical connections between the plural battery cells incorporated in the battery pack  10 . 
     The negative electrode  503  and the positive electrode  504  are electrically connected to each other inside the battery pack  10 . No limitations are imposed on the manner of connection. 
     The positional relationship between the partition wall  10   k  and the slit  61  depends on whether the positive terminal side of one of the associated battery cells is located on the right or left of the partition wall  10   k . In the sectional view of  FIG. 4 , the positive terminal  502  of the battery cell  500   b  is located on the right of the partition wall  10   k . In this case, since a space for accommodating the positive terminal  502  of the battery cell  500   b  needs to be formed under the slit  61 , the partition wall  10   k  is disposed under the left wall of the slit  61 . 
     The left wall of the slit  61  need not always be disposed right over the partition wall  10   k . For example, as shown in  FIG. 5 , a slit  61   a  (or slit  62   a ) may be formed which is wider in the X direction than the slit  61  (or slit  62   a ). In this case, the left wall of the slit  61   a  is disposed on the left (on the battery cell  500   a  side) of the upper extending line of the partition wall  10   k.    
     With the configuration described in the above, each of the slits  61  and  62  is formed in the space that is formed when the associated battery cells are arranged adjacent to each other in the longitudinal direction of the battery pack  10 . That is, each of the slits  61  and  62  is disposed so as to avoid interference with the associated battery cells. As a result, the thickness of the battery pack  10  in the Z direction is not increased by the formation of the slits  61  and  62  and depends on only the diameter of the battery cells as in the case of conventional battery packs. 
     The internal structure of the battery pack  10  will continue to be described with reference to  FIG. 6 .  FIG. 6  is a sectional view, taken along line VI-VI in  FIG. 3 , of part of the battery pack  10  (line VI-VI is drawn so as not to coincide with either of the slits  61  and  62  extending in the Y direction). 
     As shown in  FIG. 6 , the top face  10   a  of the battery pack  10  is formed with the slit  60 . A partition wall  10   m  is erected from the bottom face  10   b  of the battery pack  10  toward the bottom wall of the slit  60 . The partition wall  10   m  is a member for partitioning the space where battery cells  500   c  and  500   d  are placed. It is obligatory to partition the space where the battery cells  500   c  and  500   d  are placed in constructing the battery pack  10 . In the embodiment, the battery cells  500   c  and  500   d  are cylindrical cells. The battery cells  500   c  and  500   d  are thus disposed on both sides of the partition wall  10   m.    
     As for the positional relationship between the partition wall  10   m  and the slit  60 , the partition wall  10   m  is disposed so as to intersect the bottom wall of the slit  60  approximately at the center, in the Y direction, of the slit  60 . It is therefore preferable that the slit  60  be formed so as to be symmetrical with respect to the center line, extending in the Z direction, of the partition wall  10   m . However, the positional relationship between the partition wall  10   m  and the slit  60  may not be limited to the above one. 
     With the above structure, the slit  60  is formed in the space that is formed when the associated battery cells are arranged adjacent to each other in the shorter-axis direction of the battery pack  10 . That is, the slit  60  is disposed so as to avoid interference with the associated battery cells. As a result, the thickness of the battery pack  10  in the Z direction is not increased by the formation of the slit  60  and depends on only the diameter of the battery cells as in the case of conventional battery packs. 
     Next, how the battery pack  10  is housed in the battery holder  9  will be described in detail with reference to  FIG. 7 . 
       FIG. 7  is a sectional view taken by a plane that intersects the beam  50 , extending in the X direction, of the main unit  2  (and the slit  60 ) in the state that the battery pack  10  is housed in the battery holder  9 . 
     As shown in the sectional view of  FIG. 7 , the top wall  9   a  of the battery holder  9  is formed under the ceiling wall  2   j  which is part of the case  2   a . That portion of the case  2   a  which has the ceiling wall  2   j  and the top wall  9   a  has a thickness T. The ceiling wall  2   j  and the top wall  9   a  may constitute a single, integral member rather than are the two separate members. The top wall  9   a  is formed with the beam  50 . 
     The top face  10   a  of the battery pack  10  is formed with the slit  60  which is fitted with the beam  50  in the state that the battery pack  10  is housed in the battery holder  9 . As described above with reference to  FIGS. 4-6 , the spaces for accommodating the battery cells are secured between the top face  10   a  and the bottom face  10   b.    
     In the state that the battery pack  10  is housed in the battery holder  9 , the top wall  9   a  and the top face  10   a  are generally in close contact with each other without interfering with each other. The beam  50  is fitted in the slit  60 . It is preferable that molding be performed so that the length (height), in the Z direction, of the beam  50  is equal to or shorter than the length (depth), in the Z direction, of the slit  60 . 
     With the above structure, the case  2   a  of the main unit  2  can be made thinner in the Z direction in the region where the battery pack  10  is housed. 
     In the main unit  2 , the structure that is found in a sectional view taken by a plane that intersects the beam  51  or  52  (slit  61  or  62 ) extending in the Y direction is approximately the same as the structure that is found in a sectional view taken by a plane that intersects the beam  50  (slit  60 ) extending in the X direction (see  FIG. 7 ). 
     Next, how the top face  10   a  of the battery pack  10  is formed with the slits  60 - 62  will be described with reference to  FIG. 8 .  FIG. 8  is a top view of the battery pack  10 . 
     In the embodiment, the battery pack  10  is provided with the two nails  10   d  and the one connector  10   c  on the front side and is provided with the two ribs  11  on the rear side. Six battery cells  500   a - 500   f  are incorporated in the battery pack  10 . The battery cells  500   a - 500   f  are disposed so that their positive terminal sides and the negative terminal sides are arranged alternately in the X direction. Although each of the battery cells  500   a - 500   f  is oriented so that its negative terminal side and positive terminal side are located on the left side and the right side in the X direction, the invention may not be limited to such a case. 
     The slit  60  which extends in the X direction is formed between a front housing portion where the battery cells  500   a - 500   c  are housed and a rear housing portion where the battery cells  500   d - 500   f  are housed. The slit  60  is parallel with the longitudinal directions of the battery cells  500   a - 500   f.    
     The slit  61  which extends in the Y direction is formed between a right housing portion where the battery cells  500   c  and  500   d  are housed and a middle housing portion where the battery cells  500   b  and  500   e  are housed. The slit  62  which extends in the Y direction is formed between the middle housing portion where the battery cells  500   b  and  500   e  are housed and a left housing portion where the battery cells  500   a  and  500   f  are housed. The slits  60  and  61  are formed parallel with the shorter-axis directions of the battery cells  500   a - 500   f . The slits  60  and  61  are located over the positive terminals of the battery cells  500   b - 500   e.    
     The slit  60  extending in the X direction intersects the slits  61  and  62  extending in the Y direction. 
     In other words, the battery cells  500   a - 500   f  of the battery pack  10  are arranged in the X direction and the Y direction. The slits  60 - 62  are formed on lines that are obtained in the top face  10   a  when the boundaries between the battery cells  500   a - 500   f  are projected in the Z direction onto the top face  10   a . In particular, the slits  61  and  62  are formed so as to go along regions that are obtained in the top face  10   a  when the positive terminals (positive pole terminals) of the battery cells  500   b - 500   e  are projected in the Z direction onto the top face  10   a.    
     The positions of the positive terminal side and the negative terminal side of each of the battery cells  500   a - 500   f  in the X direction may not be limited to those shown in  FIG. 8 . 
     Although in the embodiment the battery cells  500   a - 500   f  are cylindrical cells, the invention can also be applied to cases of using square-shaped cells or laminate cells. 
     As described above, in the embodiment, the top wall  9   a  (part of the case  2   a ) of the battery holder  9  which is provided in the notebook PC  1  is formed with the beams  50 - 52 . Since the top wall  9   a  is increased in strength (reinforced) by the beams  50 - 52 , that portion of the case  2   a  which is located over the battery holder  9  can be reduced in thickness. The top face  10  of the battery pack  10  which is housed in the battery holder  9  is formed with the slits  60 - 62  without any increase in the thickness of the top wall of the battery pack  10 . The slits  60 - 62  are fitted with the respective beams  50 - 52  of the battery holder  9 . Therefore, the notebook PC  1  is kept thin even in the state that the battery pack  10  is housed in the battery holder  9 . In conclusion, the electronic apparatus can be made thinner while the strength of the case of the electronic apparatus main body is increased. 
     Although the embodiments according to the present invention have been described above, the present invention may not be limited to the above-mentioned embodiments but can be variously modified. Components disclosed in the aforementioned embodiments may be combined suitably to form various modifications. For example, some of all components disclosed in the embodiments may be removed or may be appropriately combined. 
     Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects may not be limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.