Patent Document

FIELD 
     The present disclosure relates to analog displays for measured quantities, and more particularly to an instrument cluster having a light source that emits light in the form of a virtual pointer that selectively illuminates the measured quantities on a display field, the instrument cluster further comprising at least one user actuated button that selectively blocks or redirects the light to signify a status change. 
     BACKGROUND 
     This section provides background information related to the present disclosure which is not necessarily prior art. 
     Automotive instrument clusters typically comprise large discreet display areas for a speedometer and a tachometer, and a number of smaller displays for coolant temperature, oil pressure, oil temperature, fuel level and the like. Arranged within and around the cluster are other indicators showing low fluid level conditions, turn signal operation, emergency light blinkers and so forth. The analog displays within the display fields can be provided by means of devices having electromechanical movements for causing an angular sweep of a needle across the display field. In many systems, low values of the measured quantity are typically displayed at the left side or bottom of the display field, high values at the right side or top of the display field, and intermediate values at incrementally spaced locations between the left and right sides. 
     Many instrument clusters also incorporate user actuated members, such as push buttons or rotary switches for performing a predetermined action. For example, push buttons can be incorporated on an instrument cluster to communicate a user input to a display or trip computer, to reset an odometer, reset an oil life indicator, or perform other actions. Display systems, which are described in U.S. Pat. No. 7,193,729 and co-pending U.S. patent application Ser. No. 12/275,365, employ a scanning light source to produce pulsed light beam sweeping across the display field. The present teaching utilizes the same scanning light source and portions of the display field to provide user activated members while keeping all features of the said display system un-affected. 
     For a display which is created using the scanning light source, it is difficult to package the cables, wires, and electrical switches and components without interfering with the path of light used for the display. Moreover a solution that is flexible in placement of the switches and does not add significant cost or complexity is desired 
     SUMMARY 
     This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. 
     A display for a vehicle can include a display field having at least one user responsive element. The user responsive element can include a fixed mirror and an associated movable light barrier. A pulsed light source can produce a light beam. Means are provided for causing the light beam to repeatedly scan across the display field. A controller can be arranged to repeatedly turn the light source on at one or more predetermined scan positions to illuminate the position of the user responsive element. The controller can also be programmed to act upon a signal regarding the status of the element. A photo detector can send the signal to the controller. The fixed mirror is located to reflect the light beam to the photo detector. The light barrier is positioned to selectively block the light beam from reaching the mirror. In addition to blocking the light, the light barrier may also capture or divert the light to illuminate the user responsive element. The signal from the photo detector informs the controller whether the light barrier has been moved to block the light beam, indicating the status of the element. 
     According to additional features, the user responsive element can be configured to translate along an axis. The user responsive element can include a button wherein the movable light barrier is fixed for movement with the button. Alternatively, the user responsive element can be comprised of a transparent depression or opening in the front surface where the user can insert a finger or other object such as a pen or pencil to act as a light barrier. The user responsive element can be configured to translate from a first unactuated position to a second actuated position. The button can be biased toward the unactuated positioned. The user responsive element can be configured to rotate about an axis. The status can correspond to a first status wherein the movable light barrier is in a first location and a second status wherein the movable light barrier is in a second location translated along the axis from the first location. 
     According to still other features, the at least one user responsive element can include a first and a second user responsive element. The controller can determine which of the first or the second user responsive elements has been actuated based on a time and duration of the pulsed light and the signal from the photo detector 
     Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. 
         FIG. 1  is a front perspective view of an instrument cluster according to one example of the present teachings; 
         FIG. 2  is a schematic illustration of the instrument cluster shown in  FIG. 1  and illustrating an optical device configuration according to additional features of the present teachings; 
         FIG. 3  is a side view of a user responsive element shown in the instrument cluster of  FIG. 1  and illustrated in a depressed position; 
         FIG. 4  is a side view of the user responsive element of  FIG. 3  and shown in a withdrawn, undepressed position; 
         FIG. 5  is an exemplary plot illustrating sequences of a light beam, a button action and a photo detector signal versus time; 
         FIG. 6  is an exemplary plot illustrating a light beam, button action and a photo detector signal for six distinct user responsive elements versus time; 
         FIG. 7  is a side view of a user responsive element constructed in accordance to additional features of the present teachings and shown in a withdrawn or undepressed position; 
         FIG. 8  is a side view of the user responsive element of  FIG. 7  and shown in a depressed position; 
         FIG. 9  is a side view of a user responsive element configured for translation and rotation according to additional features of the present teachings; 
         FIG. 10  is a plan view of the user responsive element of  FIG. 9 ; 
         FIG. 11  is a side view of a user responsive element, a button in the normal position illuminated by the light beam and blocking the light from the fixed mirror and the photo detector; 
         FIG. 12  is a side view of a user responsive element, a button in the actuated position with light passing to the photo detector via the fixed mirror; and 
         FIG. 13  is a side view of the user responsive element, in the actuated position using a finger to block the light. 
         FIG. 14  is a side view of the user responsive element, in the normal position without a light blocking object present, and with light passing to the reflector and to the photo detector. 
     
    
    
     Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION 
     Example embodiments will now be described more fully with reference to the accompanying drawings. 
     With initial reference to  FIG. 1 , an instrument cluster constructed in accordance with one example of the present teachings is shown and generally identified at reference numeral  10 . The instrument cluster  10  can include a fascia  12  having a display or activity field  14 . The display field  14  can comprise a dial plaque  18 . The dial plaque  18  in one exemplary embodiment may be taken to be representative of a speedometer display with low values at the left end and higher values toward the right-most or clockwise end. In this way, the dial plaque can comprise a set of indicia  20  arranged generally around the dial plaque  18  to indicate a measured quantity (such as a vehicle speed). Those skilled in the art will readily appreciate that while the dial plaque  18  has been representative of a speedometer to indicate vehicle speed, the dial plaque  18  can be configured to represent indicia indicative of any measured quantity such as, but not limited to, engine speed (a tachometer), a coolant temperature, a fuel level, an oil pressure, a cabin temperature, and outside temperature, time (a clock) and the like. 
     It is appreciated that the cluster  10  can be arranged in any vehicle, such as an automobile, an aircraft, a boat, or for various parameters in a power plant or other application displaying information to an operator. The indicia  20  can be in the form of increment or scale markers  22  that may be preprinted on the dial plaque  18  to give values to the measured quantities in miles per hour, kilometers per hour, degrees, rpm, psi, minutes, etc. The outline of the dial plaque  18  may also be printed, embossed or otherwise created on the fascia  12  of the cluster  10  for function and aesthetic appeal. 
     Various non-analog displays or “telltales” collectively referred to at reference numeral  24  can include a low fuel display  26 , turn signal arrows  28 ,  30 , engine temperature  32 , high beam light  34  and check engine  36 . Other telltales may also be provided. It will be noted that the telltales  24  can be physically arranged so as to correspond generally at an elevation on the dial plaque  18  consistent with the indicia  20 . 
     The user responsive elements or buttons  38   a ,  38   b  can be provided on or near the display field  14  of the instrument cluster  10 . The portion of the display field occupied by button  38   a ,  38   b  is the activity field. As will be described in detail herein, the buttons  38   a ,  38   b  can be configured to perform any action, such as but not limited to, resetting a displayed quantity on an information display  39  (i.e., such as a trip odometer) upon user actuation of the buttons  38   a ,  38   b . The buttons  38   a ,  38   b  can be actuated by any movement, such as linear translation, rotation about its axis and/or pivoting about an axis. 
     According to one example, illumination markers are created in the display field  14  around a 360° sweep of the dial plaque  18  to identify a desired, measured quantity value on the dial plaque  18 , such as at the indicia  20  as well as concurrently illuminating any combination of the telltales  24  identified above. These illumination markers are created by a light source  40  which operates in an on/off mode under the control of a high-speed controller  44 . In one example, the light source  40  can comprise a diode laser. In another implementation the light source  40  can comprise a light emitting diode (LED) and an optical element. The controller  44  can be configured to receive vehicle inputs from various vehicle components (not shown). The controller  44  can include signal interpretation algorithms that interpret the vehicle inputs and generate a set of light source on/off sequential signals as will be described. In one example, multiple transducers can be provided that are capable of sending electrical signals representing instantaneous values of the various measure quantities. The conversion of the electrical signals from analog to digital form may be carried out either within the controller  44  or externally thereof by a suitable ND converter according to the preferences of the system. 
     The light source  40  according to a first example is configured to output an incident or primary beam of light  50  in a direction toward an optical device  52  that is mounted for rotation about an axis  54 . The optical device  52  can be a simple curved surface mirror (like in the example shown in  FIG. 1 ) or other configurations (like the optical device  52 ′ shown in  FIG. 2 ) or more complex optical components or systems that are capable to redirect and spread or focus the incident light. 
     The optical device  52  can have a reflective surface  56 . The optical device  52  can be rotated by way of a shaft  58  that extends from a motor  62  at a high and continuous rate of speed so that the light reflected off the optical device  52  (hereinafter referred to as a secondary beam  66 ) sweeps angularly across the display field  14  from left to right in a clockwise fashion as explained in greater detail below. In the exemplary configuration of  FIG. 1 , the optical device  52  is located generally within a boundary of the dial plaque  18  and is operable to reflect light 360° around the dial plaque  18  to illuminate in any combination the indicia  20  and the telltales  24 . Additional details regarding the configuration and operation of the optical device  52  or  52 ′ and other suitable optical device configurations may be found in commonly owned U.S. Pat. No. 7,193,729 and co-pending U.S. patent application Ser. No. 12/275,365, which are expressly incorporated herein by reference. 
     The secondary beam  66  that is reflected off of the optical device  52  can also be reflected toward a photo-detector sensor  70 , the output of which is connected as an input signal  72  to the controller  44  for calibrating or “zeroing” purposes explained in detail below. In one example, a signal, hereinafter angular position signal  74  can be sent from the motor  62  to the controller  44  indicative of an angular position of the shaft  58  (and therefore the angular position of the optical device  52 ). In one example, the motor  62  can be a brushless DC motor. 
     In operation, the light source  40  can be turned on to produce a calibration pulse, which is directed toward the photo-detector  70 . This resets the data in the controller  44  to the zero-sweep position 
     When the angular position determined from the angular position signal  74  satisfies a predetermined value, the controller  44  outputs a signal, hereinafter light signal  80  that turns the light source  40  on and a stripe-like marker of light  82  ( FIG. 1 ) is caused to appear on the dial plaque  18  of the display field  14 . The light signal  80  can include light duration and starting point with regard to the angular position signal  74  of the motor shaft  58 . The controller  44  can also output a signal, hereinafter a shaft angular speed control signal  84  to the motor  62 . The controller  44  can also have a light source driving function that compares the light signal  80  and the angular position signal  74 , determined by signal interpretation algorithms in the controller  44  and switch the light source  40  on/off per the comparison result. 
     With continued reference now to  FIGS. 2-4 , one example implementation of the present disclosure will be described. A light barrier  90   a  can be coupled for movement with the button  38   a . The button  38   a  can be biased to a withdrawn or unactuated position ( FIG. 4 ) by a biasing member  39   a . A light barrier  90   b  can be coupled for movement with the button  38   b . While the light barriers  90   a  and  90   b  have been shown generally adjacent to the respective buttons  38   a  and  38   b  in  FIG. 2  and below the respective buttons  38   a  and  38   b  in  FIGS. 3 and 4 , the light barriers  90   a  and  90   b  can be located at any suitable location for concurrent or subsequent movement with the buttons  38   a  and  38   b . A fixed mirror  92   a  can be disposed generally adjacent to the button  38   a . A fixed mirror  92   b  can be disposed generally adjacent to the button  38   b . A fixed zero position mirror  96  can be provided for reflecting light toward the photo detector  70  as will be described. 
     During operation, the respective light barriers  90   a  and  90   b  are configured to block the respective secondary beams of light  66   a   1  and  66   b   1  from reaching the fixed mirrors  92   a  and  92   b  when the respective button  38   a  or  38   b  is actuated ( FIG. 3 ). In this way, primary light  50  is emitted from the light source  40  and reflected off surface  56  of the optical device  52 ′ and directed as a secondary beam  66   a   1  toward the fixed mirror  92   a . If the button  38   a  has not been actuated (such as in a withdrawn position,  FIG. 4 ), the secondary beam  66   a   1  reflects off of the fixed mirror  92   a  as a tertiary beam of light  66   a   2  toward the photo detector  70 . If the button  38   a  is actuated (such as in a depressed position,  FIG. 3 ), the light barrier  90   a  will block the secondary beam  66   a   1  from reaching the fixed mirror  92   a  and therefore preclude creation of the tertiary beam  66   a   2 . Therefore, actuation of the button  38   a  will preclude a tertiary beam  66   a   2  from ever reaching the photo detector  70 . As can be appreciated, the button  38   b  can be configured similarly. In this way, actuation of the button  38   b  can move the light barrier  90   b  into alignment with the secondary beam  66   b   1 , such that the secondary beam  66   b   1  cannot reflect off of the fixed mirror  92   b  as the tertiary light  66   b   2 . 
     With continued reference now to  FIGS. 2-4  and additional reference now to  FIG. 5 , a plot of light beam  66   a   1 , button  38   a  action and photo detector  70  signal is illustrated versus an exemplary time sequence. During operation, the controller  44  turns on the light source  40  such that the light beam  66   a   1  is ultimately created from a time t 1 -t 4  and again from time t 5 -t 8  and again at t 9 -t 12 . It is appreciated that the light beam  66   a   1  is kept on through the respective durations t 1 -t 4 , t 5 -t 8  and t 9 -t 12  when the optical device  52 ′ is pointing at the appropriate angle. At some time between t 2  and t 3 , the secondary light  66   a   1  shines on the fixed mirror  92   a  and is reflected off as the tertiary beam  66   a   2 , which its aimed onto the photo detector  70 . Because the button  38   a  is not depressed ( FIG. 4 ), the tertiary light  66   a   2  reaches the photo detector  70  and the photo detector  70  produces a signal  72  back to the controller  44 . In one example, the photo detector  70  can generate a pulse signal during time t 2 -t 3  indicating that the button  38   a  is not depressed. 
     At some time between t 4  and t 5 , the button  38   a  is depressed causing the movable light barrier  90   a  to block the secondary beam  66   a   1  from reaching the fixed mirror  92   a . As a result, the scheduled pulse on the signal  72  is missing from the time duration t 6  to t 7 , indicating that the button  38   a  is depressed ( FIG. 3 ). At some time before t 9 , the button  38   a  is released causing the movable light barrier  90   a  to withdraw and the secondary beam  66   a   1  to reach the fixed mirror  92   a  again. As a result, the scheduled pulse on the signal  72  appears in the time duration between t 10 -t 11  indicating that the button  38   a  is not depressed. 
     In one example, the time duration between t 4  and t 5 , as well as t 8 -t 9  can be equivalent to a single revolution of the optical device  52 ′. In another example, these times can define multiple revolutions of the optical device  52 ′. According to one configuration, the maximum toggle rate of the button  38   a  can be the same as the rotating rate of the optical device  52 ′. In this way, the controller  44  is not able to identify more than one button action (pushing or releasing) at an individual button within a rotating period of the optical device  52 ′. 
     Turning now to  FIG. 6 , a time sequence example is shown for a configuration having six buttons (such as  38   a - 38   f , not all specifically shown). Buttons  38   c - 38   f  can interact with light beams  66   c   1 - 66   f   1 . The exemplary time sequence illustrates actuation of the button  38   a  from a time after t 1  to a time t 6 . According to the present teachings, for multiple button implementations, since the controller  44  is aware of the exact moment of turning on and the duration of a respective light beam ( 66   a   1 - 66   f   1 ) for each of the buttons ( 38   a - 38   f ), the controller  44  is able to distinguish which missing pulse (photo detector signals  72   a - 72   f ) from the photo detector  70  is for which of the respective buttons  38   a - 38   f  in the case where multiple push-buttons are pressed simultaneously. 
     The fixed zero position mirror  96  ( FIG. 2 ) reflects a secondary beam  66   z   1  as a tertiary beam  66   z   2 . The zero position mirror  96  is strategically placed such that the time period of t 1 -t 2  is significantly different than that of t 2 -t 7 -t 1 . Therefore with proper algorithms, the controller  44  is able to distinguish the pulse  72   z  from other pulses by computing the time period between the pulses. This helps the system establishing synchronization during the start up and can be used for continuous synchronization. In the event that all buttons  38   a - 38   f  are depressed, the controller  44  receives only one pulse  72   z . As shown in  FIG. 6 , when the button  38   a  is depressed, the associated photo detector signal (i.e.,  72   a ) is absent. 
     With reference now to  FIGS. 7 and 8 , a button  110  constructed in accordance to another implementation of the present teachings will be described. The button  110  can be movably coupled with a mirror  112 . A biasing member  114  can bias the button  110  into the unactuated position ( FIG. 7 ). In the configuration shown in  FIGS. 7 and 8 , a secondary light beam  66   h   1  is not reflected to the photo detector  70  unless the button  110  is depressed. In other words, instead of seeking a missed pulse of light, the controller  44  is configured to search for present pulses to identify button activities. 
     Turning now to  FIGS. 9 and 10 , additional features of the present teachings will be described. In other configurations, the button can be configured as a stem  130  having a user engaging portion  132  supported within a stem rack  134 . A fixed mirror  138  can be supported by the stem rack  134 . A distal end of the stem  130  can support a double sided mirror  140 . The stem  130  can be configured to have six possible statuses: inactive, pushed only, turn left 90° only, turn right 90° only, push and turn left 90°, and push and turn right 90°. When turning the stem  130  left 90° (shown in solid line,  FIG. 10 ), an incident beam  150 L 1  is reflected off the mirror  140  to the photo detector  70  as a secondary beam  150 L 2 . When turning the stem  130  to the right 90° (shown in dashed line,  FIG. 10 ), the incident beam  150 R 1  is reflected to the photo detector  70  as the secondary beam  150 R 2 . The location of the mirror  140  in an unrotated position is illustrated in dotted line in  FIG. 10 . 
     When the stem  130  is not depressed, as shown in solid line in  FIG. 9 , the incident beam  150 S 1  is reflected to the photo detector  70  as a secondary beam  150 S 2 . When the stem  130  is depressed, as shown in dashed line in  FIG. 9 , the incident beam  150 S 1  is blocked by the stem  130 . Therefore, the photo detector  70  will not receive the scheduled beam  150 S 2 . When the stem  130  is not turned nor depressed, the photo detector  70  receives only the beam  150 S 2 . By combining the above examples, the controller  44  is able to distinguish the status of the stem  130  and act upon the signals (such as the pulse signals  72  discussed above) appropriately. 
     With reference now to  FIGS. 11 and 12 , a button  160  constructed in accordance to another implementation of the present teachings will be described. The button  160  can have as part of its construction an optical component  162 , which reflects the light  164  in such a way as to illuminate a face  166  of the button  160 . In  FIG. 11  it is shown that when the button  160  is in the normal (unactuated) position, after the light beam  164  strikes the optical element  162  it passes through a first opening  165  in the body of the button  160  and illuminates the face  166  of the button  160 . In  FIG. 12  it is shown that when the button  160  is in the actuated position the light beam  164  passes through a second opening  168  in the button  160  and is reflected from a fixed mirror  170 . The reflected light  172  can be directed to a photo detector such as described above. Of note, the button  166  includes an elastomeric or flexible material that can bulge outwardly ( FIG. 12 ) as a result of actuation. It is noted that the elastomeric button configuration of  FIGS. 11 and 12  can be used for any button disclosed herein. 
     With reference now to  FIGS. 13 and 14 , a user interface  178  can be constructed using a cavity  180  formed in a front surface  182  (i.e., of the instrument cluster) such that walls  184  defining the cavity  180  allow light beam  186  to pass when a blocking element  190  is not present. In the exemplary drawings, the blocking element  190  is a finger but it can be a pencil, pen, or any other object which can fit into the cavity  180  and also block the light beam  186 . In  FIG. 13  the user interface  178  is in the actuated mode with the blocking element  190  in the cavity  180  and blocking the light beam  186 . In  FIG. 14  the user interface  178  is in the normal (unactuated) mode as the blocking element  190  is removed from the cavity  180  and the light beam  186  is incident on fixed mirror  194 . The reflected light  196  can be directed to a photo detector such as described above. 
     The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

Technology Category: 4