Abstract:
A wristwatch has a rigid watchcase and opposed pairs of lugs for mounting a wristband. The watchcase houses a battery-powered quartz watch movement and includes a number of battery compartments outside of the watch movement for batteries to power the watch movement. Each battery compartment has a door that enables changing the battery in the compartment without exposing the watch movement to the outside environment. The lugs are integrally attached to the doors and provide convenient handles for opening and closing the doors.

Description:
FIELD OF THE INVENTION 
     The invention relates to battery-powered timepieces, and particularly to battery-powered wristwatches. 
     BACKGROUND OF THE INVENTION 
     Battery-powered wristwatches have become popular because of their accurate timekeeping, dependable service, and convenience. A conventional battery-powered wristwatch has a low-cost quartz watch movement housed within a watchcase. The watch movement includes a battery compartment containing a single battery to power the watch movement. 
     Although conventional wristwatches provide good service, there is room for improvement. To replace the battery, the back of the watchcase must be removed to gain access to the battery compartment. In virtually all currently produced watches this directly exposes the watch movement to the outside environment and enables pollutants and other contaminants to reach sensitive watch movement components with deleterious effects. 
     In addition it is well known that watch batteries, like many larger dry-cell batteries are not immune to leakage and when this happens the movement is often damaged. This is true even for the cells in quartz watches that have self-charging mechanisms. 
     Also it has become well established that when many watch owners who are inexperienced in handling watches attempt to install a battery they often inadvertently touch and damage delicate movement parts. This is also true of under-trained department store clerks and the like. 
     Furthermore, it is desirable to extend the operating life of the wristwatch between battery changes. It is known to provide batteries in external battery compartments outside of the watchcase to extend the operating life of the watch. However, the external battery compartments detract from the appearance of the watch and require complicated electrical connections extending between the external battery compartments and the watch movement. 
     Thus there is a need for an improved battery-powered wristwatch. The wristwatch should enable battery replacement without exposing the watch movement to the outside environment while providing longer operating life between battery changes without external battery compartments, and the movement needs to be isolated from the battery. 
     SUMMARY OF THE INVENTION 
     The invention is an improved battery-powered wristwatch that enables battery replacement without exposing the watch movement to the outside environment. The wristwatch can include two or more batteries within the watchcase, enabling longer operating life between battery changes without the need for external battery compartments. 
     A wristwatch in accordance with the present invention includes a rigid watchcase comprising an exterior portion defining an interior case compartment. A battery-powered watch movement housed within the case compartment is connected to a display, typically a pair of hands indicating the time. The watchcase includes an interior wall in the case compartment cooperating with the exterior portion of the case to define a battery compartment within the case compartment. The watch movement is outside of the battery compartment. 
     Electrical connections in the case compartment extend from the battery compartment to the watch movement to transmit electrical power from a battery in the battery compartment to the watch movement. A battery compartment door on the exterior portion of the watchcase faces the battery compartment and is movable between a closed position wherein the battery compartment is closed to retain a battery in the battery compartment and an opened position wherein the battery compartment is open to the outside environment. When changing the battery only the battery compartment is directly exposed to the outside environment. 
     In preferred embodiments of the present invention two or more battery compartments are defined within the watchcase. Each battery compartment has its own battery compartment door. In a particularly preferred embodiment the watchcase has four battery compartments, each battery compartment adjacent a lug or horn for mounting a conventional wristband. Each lug is an integral part of and extends from a respective battery compartment door to form a convenient handle for opening and closing the door. 
     Noteworthy of mention is the fact that, unlike mechanical spring driven movements, the smaller quartz movements have virtually the same degree of accuracy as the larger quartz movements. Thus, even with four batteries, the overall size of the improved watch in accordance with the present invention needs to be no larger than an average size conventional wristwatch. 
    
    
     Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying three drawing sheets illustrating one embodiment of the invention. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a top view of a wristwatch in accordance with the present invention; 
     FIG. 2 is a view similar to FIG. 1 but with the watchband and watchcase bezel removed; 
     FIG. 3 is a partial side view taken along Line  3 — 3  of FIG. 2; 
     FIG. 4 is an enlarged top view of a battery compartment of the watchcase shown in FIG. 2, illustrating insertion of a battery into the open battery compartment; 
     FIG. 5 is an enlarged top view of a rotary switch in the watchcase shown in FIG. 2, the switch connected to a switch crown that enables a user to select which battery powers the watch movement; 
     FIG. 6 is a vertical sectional view taken along the longitudinal axis of the switch stem connecting the rotary switch and switch crown; 
     FIG. 7 is a side view of the watchcase taken along Line  1 — 1  of FIG. 1; 
     FIG. 8 is a partial section view taken along line  8 — 8  of FIG. 4; 
     FIG. 9 is an enlarged top view of a portion of the rotary switch assembly shown in FIG. 5, the switch in a first operating position; 
     FIG. 10 is a view similar to FIG. 9 but with the switch in a second operating position; 
     FIG. 11 is a sectional view taken along line  11 — 11  of FIG. 5; and 
     FIG. 12 is a sectional view taken along line  12 — 12  of FIG.  5 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1-12 illustrate a wristwatch  10  in accordance with the present invention. The watch  10  includes a rigid watchcase  12  housing a battery-powered quartz watch movement  14  in the case  12 . The watch movement  14  is conventional and so will not be described in detail. The watch movement  14  drives an analog display  16  to indicate the time. The display  16  includes hour, minute and second hands located above a watch dial. The watch movement  14  includes a control stem that extends outside of the watchcase to a control crown  18  for setting and otherwise controlling the watch movement such as the setting of a day-date mechanism (not shown). 
     Four batteries  20   a ,  20   b ,  20   c  and  20   d  (shown in phantom in FIG. 1) within the watchcase  12  provide power to the watch movement  14 . Each battery  20  can be user-selected to energize the watch movement via a switch crown  22  on the side of the case. The switch crown  22  is connected to a switch apparatus that opens and closes electrical connections between the batteries and electric contacts on the watch movement  14  as will be described in greater detail below. 
     Pairs of horns or lugs  24  are located on opposite ends of the watchcase  12 . Each pair of lugs  24  extend outwardly away from the case  12  and are configured to hold a respective spring bar of a conventional watchband  26  between them in a known manner. 
     The watchcase  12  is formed from a bezel  28  on the top or upper side of the watchcase and a metal lower case member  30  on the back or lower side of the watchcase  12 , with outer edges of the bezel  28  and case member  30  joining the upper and lower sides of the watchcase  12  (see FIG.  7 ). The bezel  28  includes a bezel case member  32 , bezel retaining ring  34  and transparent crystal  36 . The retaining ring  34  is secured to the bezel member by screws  38  that extend through the ring  34  and case member  32  and into threaded holes formed in the lower case member  30  to clamp the bezel  28  and lower case member  30  together. Other watchcase constructions are known and can be readily adapted for use with the present invention. 
     The bezel  28  and lower case member  30  together define an interior case compartment for housing the watch movement  14  and batteries  20 . FIG. 2 illustrates the watchcase  12  with the bezel  28  removed to view the interior of the case compartment. The lower case member  30  has four sidewalls  40  formed on the upper side of the case member, each sidewall  40  defining a portion of a respective battery compartment  42 . Pairs of sidewalls  40  are formed on opposite ends of the watchcase, each sidewall  40  adjacent a respective lug  24 . A central sidewall  44  defines a watch movement compartment spaced from the battery compartments, with the watch movement  14  retained in the watch movement compartment. The watch movement and battery compartments are open at the upper side of the lower case member  30  and extend only partway through the thickness of the case member  30 . The bezel  28  and lower case member  30  form the roof and floor respectively of the watch and battery compartments. 
     Each battery compartment  42  is defined by similar construction and so only one battery compartment will be described in detail. The sidewall  40  defines a cavity at the outer edge of the lower case member  30 . A battery compartment door  46  is movably mounted on the edge of the lower case member  30  adjacent the battery compartment  42  to open and close the battery compartment. A hinge or pivot axle  48  attached to the lower case member  30  pivotally connects the door  46  to the lower case member  30 . The pivot axle  48  defines an axis of rotation of the door. 
     The door  46  is movable between a closed position shown in FIG. 2 wherein the battery compartment is closed and an opened position shown in FIG. 4 wherein the battery compartment is open for inserting or removing a battery  20 . The door  46  forms a portion of the sidewall defining the battery compartment  42  when the door is closed. A screw  50  normally holds the door tightly closed against the lower case member  30  as shown in FIG.  3 . 
     In the illustrated embodiment each lug  24  is mounted on a respective door  46 . The lug  24  projects outwardly from the door and forms a convenient door handle to open and close the compartment door  46  when replacing a battery. 
     Electrical connections within the watchcase compartment extend from each battery compartment  42  to electrically connect the batteries  20  to the watch movement  14 . In the illustrated embodiment the watch movement  14  is a low cost, readily available movement originally intended to be operated by a single self-contained battery like a battery  20 . The watch movement  14  includes its own battery compartment  52  and a blade contact  54  positioned over the battery compartment  52 . A battery terminal of a battery inserted in the battery compartment  52  would contact the blade contact  54 . The blade contact  54  is wired to a conventional drive mechanism (not shown) in the watch movement  14  that drives the time display. The other battery terminal would contact the floor of the battery compartment  52  formed by the lower case member  30 . The case member  30  is metallic and is intended to ground the other battery terminal and form the return conduction path from the drive mechanism to such other battery terminal. 
     The wrist watch  10  is powered by the watch batteries  20  and does not include a battery in the watch movement battery compartment  52 . However, the electrical connections use the blade contact  54  as a common contact to power the watch movement as described below. The lower case member  30  acts as a ground forming the return conduction path from the watch movement  14  to each of the batteries  20 . A plug or dummy battery  55  in the watch movement battery case compartment  52  engages the blade contact  54 . 
     The dummy battery  55  has the same configuration and dimensions as a conventional battery intended to power the watch movement  14 . The dummy battery  55  includes terminals or terminal areas corresponding to the positive and negative terminals of a conventional battery. An insulator separates the terminals of the dummy battery  55 . The dummy battery  55  has no interior chemicals, that if present, would produce an electrical current. The positive terminal of the dummy battery  55  is permanently attached to the lower case member  30 . When the watch movement is inserted into the case, the blade contact  54  contacts the negative terminal of the dummy battery  55  as shown. 
     Respective contact blades  56  are adjacent the roofs of the battery compartments  42  to contact a battery terminal of a battery  20  in the compartment. An insulated wire  58  extends from each contact blade  56  and is connected to a rotary switch assembly  60  located outside the watch movement  14  but within the movement compartment  44 . Each wire  58  extends through a respective through-bore  62  in the wall of the battery compartment  42  to reach the switch assembly  60 . See FIG.  8 . Each bore  62  is preferably sealed with a gasket  64  to maintain the integrity of the battery compartments. Alternatively, each wire  58  could connect to the portion of the contact blade  54  outside of the battery compartment and not extend through the battery compartment wall. Four insulated wires  66  extend from the switch assembly  60  to the contact blade  54 . Each wire  66  is associated with a respective battery compartment  42 . 
     The switch assembly  60  includes a fixed rectangular, insulated contact plate  68  held in a cutout formed in the side of the watch compartment. An operating shaft  70  extends from the switch crown  22  and is rotatably mounted in the watch casing. A reduced diameter portion of the shaft  70  extends through the center of the contact plate  68  and forms a shoulder that prevents axial movement of the shaft  70  towards the watch movement. A reduced diameter portion of the shaft  70  adjacent the switch crown  22  cooperates with an external set screw  72  to prevent axial movement of the shaft  70  to or away from the watch movement. See FIG.  8 . 
     An insulated switch plate  74  is nonrotatably carried on the reduced diameter portion of the shaft  70  and faces the contact plate  68 . The switch plate  74  is free to move or slide axially along the reduced diameter portion of the shaft  70  and is urged towards the contact plate  68  by a compression spring  76  friction clipped to the end of the shaft  70 . Pairs of raised metal contacts  78   a ,  78   b ,  78   c  and  78   d  are carried on the contact plate  68  facing the switch plate  74 . The contact pairs  78  are circumferentially spaced ninety degrees from each other about the shaft  70 . The switch plate  74  carries a jewel wheel  80  on one end of the plate and a like diameter metal wheel  82  on the other end of the plate. 
     Each battery wire  58  is connected to one side of a respective pair of contacts  78 . Each wire  66  is connected to the other side of the respective pair of contacts  78 . See FIG. 2 (for clarity the wires  58 ,  66  are not shown in FIGS.  5  and  9 - 12 ). Each set of wires  58 ,  66  forms a portion of an electric circuit between a respective battery compartment contact blade  56  and the contact blade  54 . The gap between the contacts of each contact pair  78  causes the electrical circuits to be normally open such that each battery  20  is not electrically connected to the watch movement  14  unless the gap is closed by the switch plate  74 . 
     The switch plate  74  is centered on the shaft  70  such that the jewel wheel  80  and metal wheel  82  will successively engage and contact opposed pairs of contacts  78  by rotating the shaft  70 . The metal wheel  82  electrically jumps and connects the engaged pair of contacts to close one of the circuits between a contact blade  56  and the contact blade  54 . The compression spring  76  urges the metal wheel  82  against the pair of contacts  78  to assure a dependable electrical connection is made. 
     The jewel wheel  80  is an insulator and does not electrically jump the engaged pair of contacts  78 . The jewel wheel  80  thereby maintains the open circuit between contact blade  56  and the contact blade  54  associated with the pair of contacts engaged by the jewel wheel  80 . 
     Operation of the switch assembly  60  will now be described. Fresh batteries  20  are initially placed in each of the battery compartments  42 . One terminal of each battery  20  engages a contact blade  56  and the other battery terminal engages the lower case element  30  forming the floor of the battery compartment. The rotary switch  60  is initially positioned as shown in FIG. 12, with the switch crown  22  positioned as shown in FIG.  7 . The switch crown  22  preferably includes indicia, such as the arrow shown, to provide visual feedback to the user of the angular position of the crown  22 . Indicia could also be included on the outside of the watchcase  12  if desired. 
     The metal wheel  82  acts as a jumper electrically connecting the pair of contacts  78   a , thereby electrically connecting the battery  20   a  with the watch movement  14 . The other batteries  20   b ,  20   c  and  20   d  are electrically disconnected from the watch movement  14 . The battery  20   a  is now the sole power source energizing the watch movement  14  for normal operation of the watch. 
     After the battery  20   a  is exhausted, the user rotates the switch crown  22  ninety degrees to disconnect the exhausted battery  20   a  and connect a fresh battery  20   b  to the watch movement  14 . The switch plate  74  rotates with the switch crown  22 . The metal wheel  82  travels from the contact pair  78   a  to the contact pair  78   b . The jewel wheel  80  travels from the contact pair  78   c  to the contact pair  78   d . After the switch crown  22  rotates ninety degrees the battery  20   b  is electrically connected via the contact pair  78   b  and the metal wheel  82  to the watch movement  14 . 
     The user successively rotates the switch crown  22  ninety degrees to connect a fresh battery  20   c  and then a fresh battery  20   d  to the watch movement  14 . When all four batteries  20  are exhausted, the batteries  20  are replaced with fresh batteries. The user may instead prefer to replace exhausted batteries after only three batteries are exhausted to ensure the watch is never without a reserve battery. 
     The rotary switch  60  provides tactile feedback as the user is rotating the switch crown  22 . For example, FIG. 9 illustrates the metal wheel  82  engaged with the contact pair  78   a . When switching from battery  20   a  to  20   b , the metal wheel  82  rides up and over one of the contacts of the departing contact pair  78   a  and then rides up and over one of the contacts of the arriving contact pair  78   b . The jewel wheel  80  similar rides up and over one of the contacts of the departing contact pair  78   c  and then rides up and over one of the contacts of the arriving contact pair  78   d . The wheels  80 ,  82  push the switch plate  84  towards the free end of the shaft  70 , compressing the spring  74 . FIG. 10 illustrates the metal wheel  82  on the top of one of the contacts  78   a  with the spring  74  compressed. The wheels  80 ,  82  act on opposite ends of the switch plate  74  so that the switch plate  74  slides without binding. After the wheels  80 ,  82  have passed over the contact, the spring  74  urges the switch plate  74  towards the contact plate  68 . The spring  74  elongates and relieves the resistance to rotation of the shaft  70 . 
     When rotating the switch crown  22  to switch from one battery to another, the user experiences a first resistance to rotation as the wheels  80 , 82  leave one pair of contacts  78  and then a second resistance to rotation as the wheels  80 ,  82  arrive at the next pair of contacts  78 . The initial resistance also resists inadvertent rotation of the switch crown  22  from its set position from external forces. The second resistance indicates the switch crown  22  is reaching its next intended operating position. The subsequent decrease in resistance indicates the wheels  80 ,  82  have reached their intended position engaged between the next pair of contacts  78 . 
     As described above, indicia such as the arrow on the crown provides additional verification that the switch crown  22  has reached its intended position. Further verification is provided by the second hand only moving when the crown stem is positioned properly. The switch crown  22  may be rotated in either direction, clockwise or counter-clockwise, when changing from one battery to another. 
     The wristwatch  10  provides about four times the normal operating life of a conventional wristwatch powered by a single battery. The battery compartments are completely enclosed by the compartment walls, floor and bottom when the battery doors are closed. The batteries can be replaced without exposing the watch movement to the outside environment. The illustrated embodiment uses a mechanical switch to enable the user to operatively switch between batteries. Other embodiments of the present invention can include electronic circuitry to detect a low battery condition and automatically switch from the low battery to a charged battery. 
     In yet other possible embodiments of the present invention the lower case member can be made from a nonconductive or insulating material. Being nonconductive, the lower case member cannot form a portion of the electrical connections between the battery compartments and the watch movement. In such embodiments wires or metal plates can extend from the watch movement to the battery compartments to form a portion of the electrical connections. 
     In further possible embodiments of the present invention the batteries can be connected in parallel to simultaneously energize the watch movement, and can include a battery in the watch movement battery compartment. The batteries flow current simultaneously to power the watch movement. In yet other embodiments of the present invention one or more batteries can provide power to an auxiliary device such as, for example, a lamp to illuminate the time display. 
     In other possible embodiments of the present invention a watch movement can drive a digital display or combined analog/digital display, with the means for displaying the time modified accordingly. The display of time can include the day, date or other time-related data. 
     The illustrated watch movement  14  has only one watch control to operate the watch movement and displays the time only. In still other possible embodiments of the present invention, conventional watch movements having additional watch controls can be used. These controls typically operate additional watch movement functions, such as a stopwatch, interval timer or the like. The display for indicating the time can incorporate additional displays associated with the additional functions. 
     The dummy battery  55  is configured to enable use of a conventional watch movement having a battery compartment to be used in accordance with the present invention. In other possible embodiments the watch movement can be specifically configured for use with multiple batteries in accordance with the present invention. Such watch movements can, for example, eliminate the battery compartment and incorporate terminals for electrically connecting the external batteries to the drive mechanism. 
     While I have illustrated and described a preferred embodiment of my invention, it is understood that this is capable of modification, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.