Abstract:
A miniature switch module includes a battery harness attached to a circuit board. A diaphragm or pushbutton type switch and a battery are sandwiched between the retainer and circuit board.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    This invention relates in general to electrical switches, particularly those associated with battery operated devices. 
         [0003]    2. Statement of the Problem 
         [0004]    As electronic circuitry has shrunk in size, a number of inventors have attempted to develop or improve systems for providing smaller and more compact battery supplies and switches for portable electrical devices. Space is at a premium in these devices and, because switches and replaceable batteries both need to be accessible by the user, these pose a physical limit to reducing the size of the device. One approach to solving the compactness issue employs miniature diaphragm momentary contact switches in lieu of bulkier slide, rotary, pushbutton or toggles switches. This method reduces the physical size of the switch and provides additional utility by allowing multiple actuations of a single switch to control various operating modes of the device. However, the user still requires direct access to the switch, and the switch itself consumes valuable area on both the circuit board and exterior surface of the device. 
         [0005]    Another approach replaces one of the battery contacts with an intermediate coil or leaf spring which prevents the battery contact from closing a circuit until sufficient pressure is supplied by means of a sliding or screw driven actuator. Although this method eliminates a traditional switch as a separate component, the actuator mechanism doesn&#39;t reduce the weight, bulk, or complexity of the device. In addition, this system is not suitable for reliably producing discrete momentary contact pulses required for modal control of integrated circuitry. 
         [0006]    None of the prior art approaches are able to combine both compactness and the ability to access the battery and switch. If such a switch and battery assembly were available, it would make possible a whole new spectrum of miniaturized portable battery-operated devices. 
       SUMMARY OF THE INVENTION 
       [0007]    The invention provides a synergistic solution to the above problem that couples the battery with the advantages of a momentary contact switch in an assembly that occupies less volume and less user contact area than the individual components require in less synergistic solutions. According to the invention, preferably, the mechanical switch element also provides the electrical contact to one of the poles of the battery. Further, preferably, the harness that holds the battery in the module also provides the electrical contact to the other pole of the battery, 
         [0008]    The invention provides a miniature switch and battery module comprising: a battery harness; and a printed circuit board; the battery harness and printed circuit board arranged to hold a battery between them; and a momentary switch element in electrical contact with the circuit board and located to be activated by compression against the circuit board. Preferably, the momentary switch element is selected from the group consisting of a diaphragm type switch element a push button type switch, a lever arm type switch, and a tactile type switch. Preferably, the momentary switch element is located to be in physical contact with one pole of the at least one battery when the battery is placed between the harness and the circuit board. Preferably, the momentary switch element is located between the battery and the circuit board. Preferably, the module further includes the battery, and the battery harness, the printed circuit board, and the momentary switch element are arranged in a stack so that pressure against one of the battery the harness, the circuit board and the battery, the momentary switch is activated. Preferably, an electronic device is integrated with the module, wherein the electronic device is selected from a light emitting device, a sound emitting device, a timer, a toy, and a game. 
         [0009]    The invention also provides a method of operating a momentary switch, the method comprising: stacking a battery harness, a battery, a printed circuit board and the momentary switch; applying pressure to one or more of the battery harness, battery, printed circuit board, and the momentary switch to operate the momentary switch. 
         [0010]    The invention also provides an apparatus for the electrical connection of a battery to an electrical circuit comprising at least one battery having two poles, one pole of which is placed in mechanical contact with a diaphragm type switch so that when sufficient mechanical pressure is applied to or through the battery, the switch is actuated. 
         [0011]    The invention not only provides it also provides a compact solution to the problem of accessing the switch and battery in a switchable, battery-operated device, but also does this with a sturdy and simple structure Numerous other advantages and features of the invention will become apparent from the following detailed description when read in conjunction with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is an isometric view of a preferred embodiment of the invention; 
           [0013]      FIG. 2  shows the embodiment of  FIG. 1  with the battery removed; and 
           [0014]      FIG. 3  is an exploded view of the embodiment of  FIG. 1  with additional details of the various parts shown. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0015]    The preferred embodiment of a switch module  100  according to the invention is shown in  FIG. 1 .  FIG. 2  shows the same module  100  with the battery  130  removed.  FIG. 3  shows an exploded view of switch module  100  with additional details of the parts included. Switch module  100  comprises printed circuit board  150 , momentary contact switch  120 , battery  130 , and battery harness  140 . In this particular example, module  100  is integrated with a light emitting diode (LED)  110  and functions to control the lighting of the LED. 
         [0016]    Printed circuit board  150  is made of conventional printed circuit board materials and includes electrical traces, such as  122 ,  162  and  151  ( FIG. 3 ) and an integrated circuit chip  158 . It preferably is of a shape and size to match the dimensions of  130 , which in this case is disk-shaped. Circuit board  150  includes notches  157 , the function of which will be discussed below. 
         [0017]    Momentary contact switch  120  includes mechanical switch element and battery contact  121 , momentary switch contact  162  on printed circuit board  150 , and logic included in integrated circuit chip  158 . Printed circuit board  150  with bottom face  160  contains an electronic circuit  153  having components associated with the functional performance of the switch and the electronic  110  that is operated by the switch module  100 , which, in this case is LED  110 . In this example, the circuit  153  controls the level and timing of electrical power provided to light emitting diode  110 . The particular circuits for activating and deactivating the momentary switch  120  in response to an electronic pulse and for controlling electronic device  110  are known in the art and will not be discussed in detail herein. The invention contemplates that any such circuit may be used. Mechanical switch element  121  preferably comprises a diaphragm  121  having a first battery and momentary switch contact  164  and circuit contacts  165  which are mounted over and make contact with associated conductor traces  122  on the top face  152  of circuit board  150 . A feature of the invention is that the momentary switch element  121  also provides the contact to one of the poles of the battery  130 . 
         [0018]    Battery  130  is preferably a conventional coin cell battery and preferably has negative pole  131  in contact with diaphragm switch battery contact  164  and positive pole facing toward harness  140 . This polarity is selected in this embodiment to cooperate with the voltage required by the logic in integrated circuit chip  158 . However, the opposite polarity is also possible with appropriate logic and circuit adaptations. 
         [0019]    Battery harness  140  may be any device that stabilizes and holds the battery to the circuit board  150 . A feature of the invention is that the preferred battery harness also provides the contact to one of the poles of battery  130 . Preferably, battery harness  140  comprises a disk-shaped conductor  141  having die-cut harness battery contacts  147 , preferably located near the center of the disk  141 . Harness  140  also includes legs  144  which extend around battery  130 . Legs  144  each terminate in a flange  143  having an inward bent lip  145 . Flange  143  fits into notch  157  in circuit board  150  to locate harness  140  properly with respect to the circuit elements and prevent rotary motion between the harness and circuit board. Lips  145  fits under the bottom edge of circuit board  150  and make contact with traces  151  on the circuit board. 
         [0020]    LED  110  includes electrical terminals  115  which connect to circuitry  153  on the underside of circuit board  150 . 
         [0021]    Harness  140  holds battery  130  securely in place while allowing installation and replacement of battery  130 , and also provides contact between circuit  153  and the positive pole  132  of battery  130 . It is preferably made of tin coated steel, but be made of steel with other conductive coatings, brass, or other suitable conductive material or non-conductive material with conducting coatings. It must be flexible enough to bend sufficiently when pressed to operate the switch, but sufficiently rigid to firmly hold batter  130 . When the battery is inserted, there should be enough tension between the harness, battery and circuit board to hold the battery firmly without sliding, but not so much tension as to activate mechanical switch element  121 . The actuating area  141  of harness  140  lies opposite diaphragm  121  and is flexible enough to deflect slightly when pressed by the user. Battery  130  transfers the movement of actuating area  141  to diaphragm  121  which contacts circuit trace  162  and activates switch  120 . When the user releases pressure the spring action of diaphragm  121  returns battery  130  and actuating area  141  to their original positions thus deactivating switch  120 . However, in this position, switch element/contact  121  continues to function to provide an electrical connection between the negative pole  131  of battery  130  and trace  122 . Battery  130  with positive pole  132  and negative pole  131  is mounted in harness  140  and provides electrical power to device  100 . 
         [0022]    Circuitry  153  including integrated circuit chip  158  is arranged to control the modal state of device  100  when activated. When circuit  153  is off and momentary switch circuit  120  is closed by contact of contact  164  with trace  162 , the circuit  153  is activated and, in this case, LED  110  turns on. When circuit  153  is on and momentary switch circuit  120  is closed by contact of contact  164  with trace  162 , the circuit  153  is deactivated and, in this case, LED  110  turns off. Similarly if an audio device instead of an LED was integrated with module  100 , the audio would turn on when the circuit  153  is activated and turn off when the circuit is deactivated. Similarly, the switch module  100  may be integrated with many other electronic devices. Circuit  153  may also contain elements to control the operation of the integrated electronic device  110 . For example, the LED may be a multicolored LED and the circuit  153  would include elements to sequentially turn on the various colors according to a predetermined timing sequence. 
         [0023]    Other embodiments of the invention may additionally include some or all of the following features: Larger cylindrical battery sizes and/or multiple batteries arranged in series; Location of the battery/switch on variously sized or shaped printed circuit boards; Placement of the battery/switch assembly remote from the main circuit board of the device which is serves; Arrangement of the battery/switch assembly to operate with user actuation pressure applied to the side of the assembly opposite of the diaphragm in lieu of pressure on the battery harness; Enclosure of the battery/switch assembly in compartments or containers associated with the device which is serves; Integration of discrete components of the battery/switch assembly into a single component, and; Incorporation of flexible membranes which transfer actuation pressure by the user and protect the assembly from contamination by water or debris. 
         [0024]    In its various configurations, the invention allows the battery and switch to effectively occupy the same interior volume of space while also freeing up usable area on the circuit board and exterior surface of the device which would otherwise have been devoted to the separate components. Examples of devices which could beneficially employ the invention include, but are not limited to, the following: Remote control transmitters; sound emitting devices; Flashlights; Battery operated toys and games; Miniature lighting devices; Electronic timers, and; Lighted pushbuttons. 
         [0025]    A feature of the invention is that in the preferred embodiment of the invention, momentary switch element  12  can be switched from either side of the printed circuit board. As indicated above, it can be activated by pressing on harness  140 . It can also be activated by pressing on the integrated electronic element  110 , or the circuit board  150 . Another feature of the invention is its compact size. The size is largely determined by the battery. In the preferred embodiment, it is 22 mm in diameter and 8 mm thick, including two coin-cell batteries. The thickness, excluding the battery  130  and electronic device  110  is from 2 mm to 8 mm thick, more preferably 3-6 mm thick, and most preferably, 3-4 mm thick. 
         [0026]    There has been described a novel compact, modular switch and battery holder. It should be understood that the specific formulations and methods described herein are exemplary and should not be construed to limit the invention, which will be described in the claims below. Further, it is evident that those skilled in the art may now make numerous uses and modifications of the specific embodiments described without departing from the inventive concepts. As one example, one or more batteries may be used. As another example, the elements of the device may be incorporated with a type A, type AA, type AAA, type C or type D battery. The battery will make the module larger, but at the same time the simplicity and compactness of the structure will permit much smaller modules with these types of batteries. For example, a small, push-button flashlight can be made using the principles of the invention.