Abstract:
A fixture using an electrophoretic display system is disclosed. Various construction details are developed which enable simplification of the wiring system for the elevator system. In one detailed embodiment, a touchscreen device is used with the electrophoretic device to transmit data to the elevator dispatch controller of the elevator system

Description:
TECHNICAL FIELD  
         [0001]    This invention relates to elevator systems which employ electromagnetic signals for communicating between an elevator dispatch controller and fixtures, such as hall fixtures on each floor, so that the fixtures may be used to enter data to make requests for service and for the elevator system to respond to or inform the viewers on the floors. The elevator dispatch controller may be a group controller for a bank of elevators or a single controller for a single elevator.  
         BACKGROUND OF THE INVENTION  
         [0002]    A conventional elevator system has an installation for each floor which includes an up hall call fixture, such as a request button, for requesting an elevator car from the group controller; and, an associated light for signaling that the group controller has registered the request (except for the highest floor). Similarly, the elevator system includes a down hall call request button with an associated light to indicate that the group controller has registered the request (except for the lowest floor). The elevator system also includes a gong for providing an audible signal that an elevator car is about to arrive.  
           [0003]    In addition, on each floor, each elevator hatchway has associated with it a set of hall lantern fixtures that identify which of the elevators is about to arrive, and depending on which of the lantern fixtures is lit, the direction in which the elevator is currently traveling. The highest and lowest floors have only one lantern fixture in a set of lantern fixtures; the remaining floors have two lanterns per set.  
           [0004]    Finally, on major floors such as lobby floors, car position indicator fixtures are provided for each elevator in the group, and report the current floor position of the corresponding elevator car. These are generally not provided on each floor because of the expense. The floor position is taken to be equivalent to the committable floor of the car (that is, the next floor where the car could possibly stop, or a floor where it is stopped). Each of these fixtures requires a pair of wires through the hoistway to carry signals to the fixture from the elevator dispatch controller and a pair of wires through the hoistway to carry electrical power to each of the fixtures. This is true whether a single elevator or a group of elevators is used in the installation.  
           [0005]    Regardless of how many individual processors are utilized, multi-elevator groups all employ a car controller for each car, and a group controller for the entire group. Each car controller communicates with the corresponding elevator car by means of a traveling cable, and the various car controllers communicate with the group controller over wires. In turn, the group controller communicates over wires with the hall fixtures.  
           [0006]    In large systems, that is, several groups each having 15-25 floors, the amount of wire involved in enormous. Whenever upgrading is to be achieved, modifications to the elevator wiring which is embedded in the building can be extremely difficult, if not sufficiently prohibitive so as to confine the nature of the upgrade to that which will conform to the wiring. When upgrades or new elevator systems are to be provided in occupied buildings, the time required to rewire or reconfigure the wiring of a building can be prohibitive, due to the need to have minimal intrusive shutdown of elevators during the work, so that use of portions of the elevator system by paying tenants can continue throughout the work period.  
           [0007]    One approach is to use an electromagnetic transceiver to communicate with one or more corresponding transceivers at a floor which are linked to a hall fixture at that floor. One example of this approach is set forth in International Patent Corporation Treaty Application Number WO 00/34169 entitled “Wireless Elevator Hall Fixtures” by Finn et al. which is assigned to the assignee of the present invention.  
           [0008]    In Finn, the transceivers send call requests and receive acknowledgments for the hall fixtures and send simple on and off signals to the lights associated with the fixtures. Finn mentions using liquid crystal displays in place of the lights. Finn does eliminate the need for wiring between the controllers and the individual floors, and reduces the wiring necessary on each individual floor for this purpose to a minuscule amount. Finn permits altering fixtures without regard to signal wiring already embedded in the building. Finn does eliminate the need for tremendous amounts of wire and provides flexibility. And, the teaching of Finn may be utilized in new construction to save wire and costs and permit future upgrades, as well as being advantageously used in retrofit and upgrade applications to existing systems. However, Finn does not eliminate the need for wiring to carry power to each of the fixtures and to the lights or liquid crystal displays used in place of the lights.  
           [0009]    Accordingly, the above art notwithstanding, scientists and engineers working under the direction of applicants assignee have sought to develop ways of avoiding the need to have power wires extend to each of the fixtures.  
         SUMMARY OF THE INVENTION  
         [0010]    This invention is in part predicated on the realization that a fixture having an electrophoretic display system is capable of using the electrophoretic display system in connection with wireless communication. It is also in part predicated on the realization that an electrophoretic display system has particular application to elevator systems. This occurs because the wireless communication of information to the electrophoretic display system and the amount of power required to operate the fixture makes possible an independent power source for the fixture. This, in turn, avoids complex and inconvenient wire-like connections to power sources whose remote location makes necessary the complex wiring harnesses discussed above. In particular, this avoids a continuous electrical conductor which extends from the fixture to the hoistway and thence to the power source for the hoistway or for the structure in which the elevator is installed.  
           [0011]    An electrophoretic display system  10  is schematically shown in FIG. 1. The electrophoretic display system includes many, many microcompartments, such as microcapsules  12 . Each microcapsule contains a liquid  14  and an electrophoretic material  16  disposed in the liquid. Examples of such microcapsules are shown in U.S. Pat. No. 5,961,804 issued to Jacobson et al. entitled “Microencapsulated Electrophoretic Display.” An electrophoretic material is a material that moves in response to an electronic field and includes materials which translate or rotate or both translate or rotate in such a field. As discussed by Jacobson et al., electrophoretic materials for the microcapsules include particles or liquids that are reflective or radiant.  
           [0012]    In an electrophoretic display system, the microcapsules are disposed adjacent a device, such as the two electrodes  18 ,  20  shown in FIG. 1, for imposing an electric field on the electrophoretic material. One example of an electrophoretic display system is the E Ink electronic display which is available from the E Ink Corporation, Cambridge, Massachusetts. A liquid “carrier medium” is used in one exemplary process to form an “ink” that carries and fixes the microcapsules onto virtually any surface. This may be done with existing printing processes, such as, for example, screen printing processes. In one embodiment, the E ink is printed onto a sheet of plastic film that is laminated to a layer of circuitry. The layer of circuitry (electrodes) forms a pattern of pixels that can be controlled by a display driver.  
           [0013]    The term “electrophoretic display system” also covers a similar embodiment which is known as the Gyricon system. The Gyricon system uses microscopic, charged balls painted half black and half white. The balls float in tiny liquid filled cavities and rotate in response to an electrical field to form a display. The Gyricon system was developed by the Xerox Corp., Palo Alto Research Center, Palo Alto, Calif.  
           [0014]    According to the present invention, an elevator fixture has a wireless communications system which has an electrophoretic display system for receiving and communicating visual information to passengers and which has a source of power connected to the electrophoretic display system that receives energy from the elevator system or its surroundings but is independent of continuous electrical conductors that are attached to a supplementary power source which includes the power system for the hoistway and the power system for the housing in which the elevator is installed.  
           [0015]    In accordance with one detailed embodiment of the present invention, the fixture includes a first screen for the electrophoretic display system and a second screen (touchscreen) that lies over the first screen. The second touchscreen has raised symbols on the touchscreen which may be perceived by a person who is visually challenged.  
           [0016]    In accordance with one detailed embodiment, the electrophoretic display system has reflective particles and is illuminated by ambient lighting and the power source is a photovoltaic cell which receives energy from the ambient lighting.  
           [0017]    In accordance with another detailed embodiment, the power source is a galvanic cell.  
           [0018]    In accordance with another detailed embodiment, the power source for the electrophoretic display system has a wireless interface with a supplementary source of power by using electromagnetic energy, for example, with an inductive coupling device for providing energy to a rechargeable galvanic cell.  
           [0019]    In accordance with another detailed embodiment, the power source is a galvanic cell which receives energy from a photoelectric cell.  
           [0020]    In accordance with another detailed embodiment, the electrophoretic display system has a screen which is curved.  
           [0021]    In accordance with another detailed embodiment, at least one of the elevator fixtures is selected from the group consisting of the hall lantern, the hall position indicator, the hall call fixture and the car operating panel display.  
           [0022]    A primary feature of the present invention is a fixture for an elevator having an electrophoretic display system. Another feature is the power source for the electrophoretic display system. In one particular embodiment, the power source is a galvanic cell. In one detailed embodiment, the power source is a rechargeable galvanic cell.  
           [0023]    A principal advantage of the present invention is the level of safety and reduced maintenance cost and time which results from avoiding the use of the hoistway as a source of power that has wires that are mechanically connected at the hoistway and at the fixture for supplying power to the fixture. Another advantage is the cost of installing fixtures, which results from the ability to locally install the fixture without requiring access to the hoistway. In addition, common hardware for the fixture design may be used for elevators installed in different parts of the world by accommodating different requirements for the language that is displayed by the fixture by electronically adjusting the electric field adjacent the electrophoretic material. Another advantage is the cost of maintenance which results from a less cluttered hoistway by not having wiring associated with supplying power to the fixture extend between the hoistway and the fixture.  
           [0024]    The foregoing features and advantages of the present invention will become more apparent in light of the following detailed description of the invention and in the accompanying drawing. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0025]    [0025]FIG. 1 is a simplified, schematic view of a microcapsule for an electrophoretic display system showing the relationship of the microcapsule and its particles to the electrical circuitry (electrodes) of the display system;  
         [0026]    [0026]FIG. 2 is a is a simplified, schematic, front plan view of a portion of a structure, as represented by a building, which has an elevator system and which is broken away to show the elevator system;  
         [0027]    [0027]FIG. 3 is a simplified side elevation view of the building shown in FIG. 2 with portions of the building broken away to show a car of the elevator system which is disposed in a hoistway.  
         [0028]    [0028]FIG. 4 is a simplified schematic representation of an elevator dispatch controller and a fixture which is in electromagnetic communication with the controller.  
         [0029]    [0029]FIG. 5 is a schematic, exploded perspective view of an alternate embodiment of a fixture shown in FIG. 2.  
         [0030]    [0030]FIG. 6 is schematic representation of an alternate embodiment of a hall call fixture shown in FIG. 2 under a first operative condition of the elevator system in which the fixture displays a schematic representation of both an up hall call fixture signal and down hall call fixture signal.  
         [0031]    [0031]FIG. 6A is a schematic representation of the hall call fixture shown in FIG. 6 under a second operative condition of the elevator system in which the fixture displays a down hall call fixture signal and an up hall lantern fixture signal.  
         [0032]    [0032]FIG. 7 and  7 A are schematic representations in English and German of an alternate embodiment of the hall call fixture signals and hall lantern fixture signals shown in FIG. 6 under a first operative condition of the elevator system in which the fixture displays a schematic representation of both an up hall call fixture signal and a down hall call fixture signal. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0033]    [0033]FIG. 2 shows an elevator system  24  employing the invention that serves a plurality of floors F 1 -FN. The elevator system has a plurality of elevator hatchways  26 . In this embodiment, there are four elevator hoistways C 1 -C 4 . Each floor F 1  to FN has, for each of the hoistways C 1 -C 4 , a lantern fixture  28 , as represented by the lantern fixture signals  28   d,    28   u  and a hall call fixture  32 , as represented by the button signal  32   u  and  32   d  which are one fixture but may be used as separate fixtures. As shown in FIG. 5, 6,  6 A,  7 ,  7 A, the two types of fixtures are combined.  
         [0034]    Each lantern fixture  28  has an electrophoretic display system  10  which is shown in more detail and discussed later with regard to alternate embodiments shown in FIGS. 5, 6,  6 A,  7 ,  7 A of the system and possible display signals. The lantern fixture has the down lantern fixture signal  28   d  (or image) for each floor except the lowest floor and the up lantern fixture signal  28   u  for each floor except the highest floor.  
         [0035]    Each of the floors except the top floor FN has a hall call fixture  32  which includes a touchscreen (not shown) and a electrophoretic display system (not shown), as represented by the image (signal) of a request button  32   u  and the image of an associated call-registered light  34   u,  that may comprise an image of the conventional “halo” or ring surrounding the button image  32   u.  Pressing the touchscreen above the button image  32   u  informs an elevator dispatch controller, as represented by the group controller  38 , that a passenger desires a call to travel upwardly from the related floor; and, when the group controller registers the call, it sends a signal back to change the color of the light image  34   u  so as to inform the passenger that the call has been registered. The fixture on each of the floors except the lowermost floor F 1  has a down hall call button image  32   d  and a corresponding light image  34   d.  On each floor, a gong  36  is sounded when a car in any one of the hoistways C 1 -C 4  is about to stop on the corresponding floor.  
         [0036]    Each of the hoistways C 1 -C 4  has a corresponding car controller  42 . The group of car controllers is supervised by the group controller  38 . The car controllers are interconnected with the group controller  38  by wire cables  44 . This, of course, is not difficult since it occurs on a machine floor where the wiring can be channeled through easily accessible ducts, within the space, rather than in the walls. On important floors, such as lobby floors, each of the hoistways C 1 -C 4  has a car position indicator fixture  46  that at any moment when the car is in service, displays the committable position image  46   s  of the corresponding car.  
         [0037]    As shown in FIG. 3, the conventional elevator car  52  communicates with its car controller  42  by means of a traveling cable  54 . The building includes a first source of power, as represented by the power cable  56  which is partially broken away. The power cable is connected by continuous electrical conductors (for example, wires) to a source of illumination, such as a light fixture  58 . The building has a light fixture on each floor at the elevator hatchway  26  to illuminate that area. A second source of power for the elevator system is represented by a portion of a continuous electrical conductor, such as a wiring harness  62 , which is broken away for clarity. The wiring harness may be electrically connected to an external source of power or to the first source of power for the building. A third source of power, as represented by one or more photovoltaic cells  64   c,  is illuminated on each floor by the light fixture or by natural light from the exterior of the building. Thus, the illumination is a first source of energy for the third source of power. The third source of power is local to the floor adjacent the hoistway and connected by a continuous electrical connector  65  (shown in FIG. 4) to the fixtures  28 ,  32 ,  46 . The continuous electrical connector does not extend into the hoistway. The fixtures are not connected by a continuous electrical connector to the first source of power or the second source of power.  
         [0038]    [0038]FIG. 4 is a schematic representation of the electromagnetic coupling between the elevator dispatch controller  38 , such as a group controller or an individual controller for a single elevator and a fixture  32 . The fixture  32  has an electrophoretic display  10  system such as is used with the fixtures  28 ,  32 ,  46  shown in FIG. 2. As shown in FIG. 2 and FIG. 4, the group controller  38  has an electromagnetic transceiver module  66  which communicates with any and all of the corresponding fixture transceiver modules  68  on each floor of the building. In the present embodiment, it is assumed that the fixtures have locally positioned electronics associated with them to permit operation in response to state commands. For instance, pressing the fixture above one of the call button images  32   u,    32   d  will cause a corresponding signal  72  from the fixture transceiver module  68  of the related floor indicating a request for an up call or a down call on that floor. Similarly, a single signal  74  from the group controller transceiver module  66  addressed to a specific one of the transceiver modules  68  may acknowledge the call request. These signals are thus discrete, and are responded to in order to cause the corresponding desired action. The remainder of the required signals  74  are simply to either display or not display the hall button light image  34   u,    34   d,  a lantern fixture image  32   d,    32   u  or any of the car position indicator images.  
         [0039]    As shown in FIG. 4 and mentioned above, the controller transceiver module  66  is linked to the elevator dispatch controller  38  by a continuous electrical conductor, as represented by the arrows  76  representing a two-way flow of information. A continuous electrical conductor exists where an unbroken path exists for the flow of electrical current, such as through a wire or other electrically conductive component. The link might also be provided by an electromagnetic link by being connected by an electromagnetic device. The term “continuous electrical conductor” does not include an electromagnetic link.  
         [0040]    The controller transceiver module  66  might be physically part of the elevator dispatch controller  38  or physically displaced from the elevator dispatch controller. The controller transceiver module includes a microcontroller  78 , such as a microprocessor, for translating information from the elevator dispatch controller into a signal which is sent by a RF transceiver  82  via an antenna  84 .  
         [0041]    The fixture  28  includes the fixture transceiver module  68 , at least one of the electrophoretic display systems  10 , and the third source of power  64 . The electrophoretic display system in this particular embodiment is an E Ink system available from the E Ink Corporation, Cambridge, Mass.  
         [0042]    The fixture transceiver module  68  includes an antenna  86 , a RF transceiver  88  and a microcontroller, as represented by the microprocessor  92 . The fixture transceiver module sends data signals  72  from the fixture and receives data signals  74 , such as acknowledgments, from the elevator dispatch controller. The fixture transceiver module might be physically part of the remainder of the fixture or physically displaced from the remainder of the fixture. The fixture transceiver module is connected by a continuous electrical conductor  94  to the electrophoretic display system but might also be connected by an electromagnetic device.  
         [0043]    The electrophoretic display system  10  is shown in FIG. 4 and as an illustrative alternate embodiment in FIG. 5. FIG. 5 is a schematic representation of one embodiment of this portion of the fixture. As shown in FIG. 4 and FIG. 5, the electrophoretic display system includes a display layer  96 . The layer is formed of microcapsules containing the liquid  14  and radiant or reflective particles  16 , disposed in the liquid. The principles of the electrophoretic display system is, in itself, not part of this invention  
         [0044]    The microcapsules  12  are attached to a flexible layer of supporting material  22  such as paper or thin film plastic. The paper  22  is broken away for purposes of illustration. As schematically represented in FIG. 1, the display layer includes two electrodes disposed on either side of the flexible layer which are broken away for clarity, as represented by a first electrode  18  disposed below the flexible layer on a flexible material and a second, transparent electrode  20  disposed above the flexible layer. Applying a charge to the electrode causes the positively charged particles  16  (for example, reflective white particles) to move in the liquid  14  to the display side or away from the display side. Particles on the display side cause the microcapsule (or pixel) to appear white; particles on the non-display side appear the color of the liquid (for example, blue).  
         [0045]    display driver  98  is in communication via link  102  with the electrodes  18 ,  22  to cause the appropriate symbol or letters to appear. The display driver receives information via the link, such as a continuous electrical conductor, as represented by the arrow  94 . Alternatively, there might be an electromagnetic link between the microcontroller and the display driver.  
         [0046]    The electrophoretic display system  10  might be used alone or might include in some embodiments a touchscreen device  104  as shown in FIG. 4 and FIG. 5. The embodiment shown in FIG. 4 and FIG. 5 includes a resistive touchscreen  106  such as a Densitron touchscreen available from the Densitron Corporation, 10430-2 Pioneer Boulevard, Santa Fe Springs, Calif. 90670. The touchscreen might extend over the entire display layer  96  or over a portion of the display layer where the display layer displays information not requiring an input from the viewer. The Densitron Touchscreen device includes a touchscreen, as represented by the electronics layer  106  in FIG. 4 and FIG. 5, which is in electrical communication with the Densitron touchscreen controller  108  for sending data, such as a call for an elevator car, from a hall call fixture via link  112  to the transceiver module  68 .  
         [0047]    The third source of electrical power, as represented by the block  64 , might be selected from the group consisting of photovoltaic cells  64   c,  a rechargeable galvanic cell  64   r  connected to a charging device, such as a rechargeable galvanic cell connected to photovoltaic cell  64   c,  or an electromagnetic device  64   e  which is not directly connected to the first and second sources of power by a continuous electrical conductor. An important advantage is that the third source of power for the fixture is not connected by a continuous electrical conductor to the first source of power in the building or the second source of power in the hoistway. This eliminates the need to have wires extending into the hoistway or the need to rely on and connect to the electrical power system of the building. This provides advantages in upgrading an elevator system whether a single elevator or a bank of elevators is involved. In fact, it may be nearly impossible because of cost and downtime for the elevator system to rewire an existing bank of elevators in an older installation. In such a case, new hall fixtures might be installed in parallel with existing hall fixtures because the new hall fixtures rely only on the third source of power for the energy needed to operate the fixtures.  
         [0048]    This is in part made possible by the amount of power required to operate the fixture  28 . The electrophoretic display system  10  requires an amount of power which is estimated to be ten to one hundred times less than a liquid crystal display depending on the type of display signaled by the electrophoretic display layer. For example, a fixture having a four inch by four inch display working with a touchscreen  106 , display driver  98 , touchscreen controller  108  and transceiver module  68  will require less than one hundred fifty milliwatts (150 mW) of power to change the display and nearly no power to maintain the display.  
         [0049]    The fixture transceiver module  68  might be directly connected to the second source of electrical power  64  providing that the module does not draw an amount electrical power that is excessive for the second source of electrical power. Accordingly, a particular advantage is the low power required to operate the electrophoretic display system which leaves additional power available to the remainder of the fixture.  
         [0050]    The electrophoretic display layer  96  has many advantages. For example, the fixture is flexible and may be curved as shown in FIG. 3 to form curved hall lanterns and position indicators which are viewable through a one hundred eighty (180) degree field. A viewer may see the fixture from the side such as through a side hallway. The viewer is thus informed of the location of the elevator as the viewer moves through the building; and obtains information about the status of the elevator system as the viewer approaches the elevator system.  
         [0051]    As mentioned earlier, the elevator system has many operative conditions. An elevator car might be going away from the floor (the viewer), toward the floor, resting at another floor or arriving at the floor. One or more fixtures having electrophoretic display systems  10  may be used to convey information about the car through visual signals as do conventional systems but with certain advantages. For example, a single display layer may display one, more than one, or all hall fixture visual signals such as hall call fixture signals, hall lantern fixture signals, and hall position indicator fixture signals.  
         [0052]    [0052]FIG. 6 and FIG. 6A are schematic representations of visual signals related to hall fixtures under different operative conditions. As shown in FIG. 6, a touchscreen device  104  may be used to select the “up” call direction by pressing the touchscreen  106  above the outline of the “up” arrow. Upon receiving an acknowledgment from the elevator dispatch controller, the visual signal may change to the configuration shown in FIG. 6A and display the acknowledgment of the call signal. The “Press to Select Direction” signage might appear next to the outline of the “down” call direction. Thus, the hall call fixture signal is displayed at a first location on the display layer and the touchscreen has a first location that is axially aligned with the first location on the display layer such that touching the touchscreen causes the touchscreen to send a call signal to the transceiver module  68 . After the call signal has been acknowledged, the display layer displays the hall lantern signal at the first location allowing a single fixture to perform the work of two fixtures (hall call fixture, hall lantern fixture).  
         [0053]    Finally, the overall appearance of the display layer may be easily adapted depending on customer preferences, cultures or current needs. A single piece of fixture hardware might be used for installations in the United States and the Federal Republic of Germany, displaying the English language as shown in FIG. 7A or the German language as shown in FIG. 7 b.  The fixture might be even reprogrammed to display images such as passengers performing required acts to interface with the elevator system, or a symbolic character in a smaller font.  
         [0054]    Although the invention has been shown and described with respect to detailed embodiment thereof, it should be understood by those skilled in the art that various changes in form and detail thereof maybe made without departing from the spirit and scope of the claimed invention.