Abstract:
A timer usable in navigating and piloting an aircraft, the timer having a plurality of application modes for management of time and numeric data, including an approach mode, a fuel mode, a chronograph mode and a clock mode. Each application mode can drive independent but simultaneous time count sequences for use in flight management and navigation such as counting down approach times, fuel-tank switching intervals and other time sensitive events, as well as providing military time, standard time and UTC time.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to portable flight timers for use in aviation. 
   2. Description of Related Art 
   Timing apparatus can be important to a pilot in a variety of navigational and flight management scenarios. One navigational example of where this need arises is in executing non-precision runway approaches under instrument flight rules (IFR), commonly executed by private pilots. A Missed Approach Point (MAP) can be determined based on the aircraft&#39;s predicted speed, and is the point by which the aviator must establish satisfactory visual contact with the runway or abort the landing and follow the airport&#39;s particular Missed Approach procedures. Pilots commonly use timers to countdown a predetermined time after passing a Final Approach Fix (FAF) to estimate whether the MAP has been passed. This predetermined time, the approach time, can vary depending on the speed of the aircraft. For example, several approach times may be provided to, or calculated by a pilot with each corresponding to a different approach speed of the aircraft. The actual approach time selected for use will depend on the speed of the aircraft when passing the FAF. 
   There are several circumstances in which pilots may need to have access to multiple predetermined approach times, preferably at their “finger tips.” For example, a pilot may need to fly to several destination airports or have several home airports. Each runway for those locations will have associated approach times from the FAF to the MAP depending on various factors, such as approach speed of the aircraft. Other circumstances may require a pilot to choose between a plurality of predetermined approach times just before passing a FAF because the speed of the approach can determine the appropriate approach time. 
   In another scenario, more akin to flight management, fuel in the fuel tanks on either side of a plane may have to be consumed on an alternating basis to maintain stability of the plane. The pilot can switch fuel tanks on predetermined time intervals based on the pilot&#39;s empirical experience with the plane or other knowledge of the plane&#39;s particular flight characteristics. In either case, a timer can be employed. 
   The examples provided above illustrate some timer needs for aviators and an exhaustive description here would obscure the present invention. However, even considering only the illustrated examples, one can see the need to manage event timing. That is, a pilot may need to time multiple events and access timing data simultaneously, such as timing a fuel event while selecting and starting a countdown of an approach time or monitoring a time between waypoints. In other scenarios, the pilot may need flexible timing operations, such as gauging an appropriate fuel time switching interval by counting up on a timer, then switching fuel tanks and counting down. There is a need for a portable flight timer that can be easily operated by a pilot while providing capability to manage and employ a myriad of essential time and other numeric data for use in flight management and navigation. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention resides in a portable flight timer normally used in aviation. The timer has the capability to manage and employ multiple time event related parameters that can be set by a user. In some embodiments the user, typically a pilot or navigator, can operate the flight timer in a first application mode to store multiple approach times and associate the approach times with unique identifiers to help manage the approach times. The approach times can then be selected on the flight timer during flight depending on the circumstances and counted down on the flight timer immediately after being selected. 
   In other embodiments, the portable flight timer can also be used to countdown fuel tank switching times. The flight timer can have at least a second application mode, other than the approach time mode, that allows the flight timer to count a fuel-tank-switching time that can be started or stopped independently and counted simultaneously with (or not simultaneously) a countdown sequence for an approach time. Each of the application modes can have indicators to indicate to a pilot which mode and which counting sequence he or she is viewing, and the relationship of the counting sequence to the aircraft (i.e. when viewing the fuel-tank switching count, a display of the flight timer can indicate “fuel,” while when viewing the approach time count, a display of the flight timer can indicate “approach.”) 
   In still other embodiments, the portable flight timer also has a third application mode, such as a chronograph mode that can also drive a counting sequence simultaneously with (or not simultaneously with), and independently from, the counting sequences of the approach mode and fuel mode. In this mode, the flight timer can display a counting sequence without displaying an association with approach time or fuel time such that the pilot may use this mode to time a variety of other time sensitive events in flight without confusing various counting sequences that may be running simultaneously. 
   The flight timer can also have a clock mode that is capable of display three time formats, standard, military and UTC time. Also, a note function can be available that is programmable to display a note, such as a critical cruising altitude or a radio frequency. 

   
     BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS 
       FIG. 1  is an overhead plan view of an embodiment of the flight timer of the present invention. 
       FIG. 2  is a perspective view showing a front portion of the flight timer of  FIG. 1 . 
       FIG. 3  is a perspective view showing a back portion of the flight timer of  FIG. 2 . 
       FIG. 4  is a perspective view showing a back portion of the flight timer of  FIG. 3  with the clip of the flight timer rotated ninety (90) degrees counterclockwise from its position in  FIG. 3 . 
       FIG. 5  is a simplified block diagram of various components comprising some embodiments of the present invention. 
       FIG. 6  is a step diagram for an embodiment of the present invention showing the beginning steps in selecting an application mode. 
       FIG. 7  is a step diagram for the flight timer illustrated in  FIG. 1  for setting approach time countdown settings. 
       FIG. 8  is a step diagram for the flight timer illustrated in  FIG. 1  for operating the flight timer in approach mode. 
       FIG. 9  is a step diagram for the flight timer illustrated in  FIG. 1  for setting a fuel countdown time. 
       FIG. 10  is a step diagram for the flight timer illustrated in  FIG. 1  for setting the clock of the flight timer. 
       FIG. 11  is a schematic diagram for an embodiment of the flight timer of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In the following description, certain specific details are set forth in order to provide a thorough understanding of various embodiments of the invention. However, upon reviewing this disclosure one skilled in the art will understand that the invention may be practiced without many of these details. In other instances, well-known structures associated with stopwatches, clocks and timers have not been described in detail to avoid unnecessarily obscuring the descriptions of the embodiments of the invention. 
   The discussion below discloses, among other things, using the present invention in aviation as a navigational and flight management aid or tool and describes such use and supporting structure in the context of various example embodiments. However, as well be understood by one skilled in the art after reviewing this disclosure, various other applications are contemplated, such as, for example, timing in sporting events, scientific experimentation and engineering related timing needs. 
   Terms in the following description related to orientation such as “below” and “above,” “bottom” and “top,” “left” and “right,” “up” and “down,” and “vertical” and “horizontal,” are only intended to describe the position or orientation of elements in relation to the figures in which they are illustrated. Unless the context indicates otherwise, these terms of orientation are not intended to be restrictive in meaning outside of describing the orientation of a particular element relative to the subject illustration. 
     FIG. 5  shows a simplified block diagram for some embodiments of the present invention. As can be seen, the flight timer  1  can comprise a controller  68 , such as a microcontroller or processor, connected to a memory system  70 , an alarm element  72  and a display system  66 . The memory system  70  can have volatile and non-volatile memory, such as RAM and read/write only memory (ROM) or EPROM. Also, various oscillators  62  such as a quartz crystal can be provided to generate a vibration frequency that can be monitored by one or more timers/counters  62  to produce count-up or countdown signals. The count-up or countdown signals can be displayed by the display system  66  in a numerical format understandable by a user. Furthermore, one or more input elements  60  are provided to allow a user to send signals to the various sections of the flight timer  1  components, such as to the controller  68  to perform functions or store information included in the user sent signal. The input elements  60  can comprise, inter alia, button-actuated switches and an incremental encoder switch coupled to a dial. As will be understood by one skilled in the art after reviewing the present disclosure, the elements described above can be employed in a variety of combinations to implement various embodiments of the invention as disclosed herein. 
     FIG. 1  is a front plan view of an embodiment of the present invention wherein the flight timer  1  includes a housing  46 , a display system  66  with an LCD  40 , a dial  34  and a plurality of buttons  2 ,  4 ,  6 ,  32 ,  36  and  38 . The dial  34  and buttons can be used for actuating input elements  60 , such as those described, supra. 
   Each of buttons  2 ,  4 , and  6  can be used to select a different application mode of the flight timer  1 —each application mode being applicable as an aviation tool/aid in flight management, flight navigation and general time monitoring during flight. For example, button  2  can be used to select a first application mode (approach mode), button  4  can be used to select second or third application modes (fuel time mode and chronograph mode) and button  6  can be used to selected a fourth application mode (clock mode). In some embodiments, buttons  2 ,  4 , and  6  are labeled “APPROACH,” “FUEL/CHRONO,” and “CLOCK” respectively. 
   When the approach button  2  is depressed by a user, in accordance with step  80  in  FIG. 6 , LCD positions  10 ,  20 ,  22 ,  26   a ,  28   a ,  28   b ,  30   a ,  30   b , and  8  can be active while all other display positions will be inactive. The LCD  40  will display an approach mode indicator  10 , as best seen in  FIGS. 1 and 2 . Also, in this application mode, a user can store a plurality of approach times and associate each of the plurality of approach times with a unique approach time identifier displayable in positions  20 ,  22  and  26   a  of the LCD  40 . This can be done by rotating the dial  34  to select an identifier. (See Step  90  in  FIG. 7 ). The identifiers can be preprogrammed in the ROM  70  of the controller  68  and can comprise the alphanumeric/numeric combinations H 1 , H 2 , H 3 , H 4 , H 5 , H 6 , D 1 , D 2 , D 3 , D 4 , D 5  and D 6 .  FIG. 2  shows and example embodiment of the present invention wherein the unique identifier is displayed on the LCD  40  as “APPROACH” “D 2 ” in positions  10 ,  22  and  26   a  of the LCD  40 . After a unique identifier is selected, a user can set the approach time to be associated with the unique identifier. 
   In some embodiments of the present invention, a user sets minutes by first pressing the dial  34  (See Step  92  in  FIG. 7 ) to activate a minutes setting mode, and then rotating the dial  34  to select the appropriate number of minutes for the approach time. (See Step  94  in  FIG. 7 ). Once the desired minutes are set, the user can lock the minutes setting by again pressing the dial  34  (See Step  96  in  FIG. 7 ). The flight timer  1  will then be in seconds setting mode and allow a user to select seconds by again rotating the dial  34 . (See Step  100  in  FIG. 7 ). Once a user is satisfied with the seconds setting, the dial  34  or approach button  2  can be pressed again to lock the setting (See Step  102  in  FIG. 7 ). 
   After the seconds setting is locked, the user may rotate the dial  34  to select another approach time identifier and set and store another approach time, etc., until the approach time storage capacity is reached for the flight timer  1 . The illustrated embodiment of the flight timer  1  in  FIGS. 1 and 7 , is capable of storing a total of twelve (12) approach times. Other embodiments can store less than twelve (12) approach times or more than twelve (12) approach times that can each be associated with unique identifiers. 
   In the illustrated embodiments, the alphanumeric portion of the unique approach time identifiers denote home and destination airports. For example, H 1 , H 2 , H 3 , H 4 , H 5  and H 6  denote six (6) different stored approach times for home airports and D 1 , D 2 , D 3 , D 4 , D 5  and D 6  denote six (6) different stored approach times for destination airports. As will be understood by one skilled in the art after reviewing the present disclosure, the identifiers displayed can take on a variety of forms, as is contemplated herein. The identifiers could, for example, be numerical identifiers only (e.g.,  1 – 12  or  1 – 24 ) or can include additional letter characters (e.g., Home One, Home Two). The mode indicator, such as “APPROACH” in position  10  of the LCD  40 , is part of the identifier for each approach time, indicating the relationship of the displayed value and letters to approach times to the pilot. Again, other abbreviations or variations for the display in position  10  (e.g., “A,” “AP,” “AT,” “APP.”, etc.) are contemplated as long as they are sufficient to convey the mode of the flight timer to an aviator so that the aviator immediately understands which type of number he or she is viewing, that is, an approach time. 
   Pilots can apply the approach mode in different ways. For example, the plurality of stored approach times can each be used for different runways/airports. Alternatively, different approach times could be stored for different approach speeds. For example, two (2) or three (3) different approach times could be stored for a single home airport based on two different approach speeds and selectively used depending on the actual speed at the time of approach. 
   In practice, a pilot can apply the approach mode of the flight timer  1  by first depressing the approach button if needed (See Step  80  in  FIG. 6 ) and then selecting a stored approach time by rotating dial  34 . (See Step  106  in  FIG. 8 ). In this manner, the pilot may toggle through the unique identifiers for the purpose of identifying and selecting the appropriate associated approach time setting. Once the user stored approach time is selected, the pilot can begin a countdown sequence from the stored approach time by depressing the start/stop switch  42  (Step  108  in  FIG. 8 ) when the pilot&#39;s plane passes, for example, a Final Approach Fix. 
   In some embodiments, when and if the countdown sequence started by a user in the approach mode reaches zero, the alarm  72  is engaged. A user can stop the alarm by depressing the start/stop button  42 . The alarm can comprise three simultaneous alarm indicators: (i) an audible signal; (ii) a flashing backlight that illuminates at least a portion of the LCD  40 ; and (iii) flashing of the numeric characters,  28   a ,  28   b ,  30   a ,  30   b  that display the status of the counting sequence for the approach mode (and the numeric portion of the unique identifier,  26   a ). If the user is in a different application mode or selects a different application mode (e.g., fuel timer mode or chronograph mode) while the approach time alarm is engaged or has been engaged, the alarm will comprise the following simultaneous indicators: (i′) the indicator “APPROACH” in position  10  of the LCD  40  will flash on and off; (ii′) the backlight will flash; and (iii′) the audible signal will sound. In either case, in order to stop the flashing of LCD  40  numeric characters or the “APPROACH” indicator, a user will need to select the approach mode of the flight timer and then depresses the start/stop button  42 . The flashing backlight and audible signal, on the other hand, can be configured to automatically discontinue after about ten (10) seconds. In other embodiments, the flashing backlight and audible signal can continue for a longer or shorter period of time. The simultaneous occurrence of the audible signal, flashing display characters and flashing backlight help ensure that a pilot will notice the alarm. Furthermore, the flashing “APPROACH” indicator in position  10  of the LCD  40  helps ensure that a pilot will be aware of the approach time alarm even when he or she has selected a different application mode. Alternatively, in other embodiments, the alarm can comprise various combinations of visible or audible alarms or consist only of one or more visible or audible alarms. Also, all of the alarms indicators can be configured to continue until a user stops them by actuating an input element. 
   In some embodiments, the approach time can be stored in memory, such as RAM, after being counted down or after being set by a user (as discussed above). For example, during a countdown sequence of an approach time, the user can stop the countdown by depressing the start/stop button  42  and this partially-counted-down value will be stored in memory  70 . The user can then begin the countdown again from this partially-counted-down value by again depressing the start/stop button  42 . Alternatively, in some embodiments, the user can depress the reset button  32 , which sets the stored approach time to zero. The user can then initiate a count-up sequence from zero on the flight timer  1 , or set a new approach time in accordance with  FIG. 7 . 
   In other embodiments, the flight timer is configured such that depressing the reset button  32  twice is required before an approach time will be set to zero. In such embodiments, depressing the reset button  32  only once resets the approach time to the previously stored value selected by the user, such as an approach time set in accordance with  FIG. 7 . In this manner, a user can restore a stored approach time after counting it down by simply depressing the reset button  32  without having to use the dial  34  to reset it. 
   When the fuel timer mode is selected by depressing button  4  in accordance with Step  82  of  FIG. 6 , positions  12 ,  26   a ,  26   b ,  28   a ,  28   b ,  30   a ,  30   b , and  8  of the LCD  40  are active while all other positions of the display are inactive. The display will indicate the fuel timer mode to a user by displaying “FUEL”  12  on the LCD  40 . A user may then initiate a countup sequence by depressing the start/stop button  42 , provided that positions  26  ( 26   a ,  26   b ),  28  ( 28   a ,  28   b ) and  30  ( 30   a ,  30   b ) of the LCD  40 , which are configured to display hours, minutes and seconds, are all set at zero. If they are not, a user may set them to zero by depressing the reset button  32  before starting the countup sequence. If a time other zero is displayed on the LCD  40 , depressing the start/stop button  42  will start a countdown sequence from the time displayed. 
   A user can set a countdown value for the fuel timer. As best seen in  FIG. 9 , the steps for setting the countdown value for the fuel timer are substantially similar to the steps for setting the approach times. That is, setting the fuel timer also comprises depressing the dial  34  to activate setting modes for minutes and seconds and the dial  34  can be rotated to select numerical values for entry. However, the fuel mode in the illustrated embodiment also includes active positions  26  ( 26   a ,  26   b ) on the LCD  40  for displaying hours. Therefore, in the illustrated embodiments, depressing the dial  24  will first activate the hours setting mode, which can be set by rotating the dial  34 . (See Steps  112  and  113  in  FIG. 9 ). After a user has selected a numerical value for the fuel countdown time, dial  34  can be pressed to lock the setting (until a countdown is started or a new setting is entered) as is the case in the approach mode. 
   In some embodiments a pilot may set a countdown value in the fuel timer mode, and then countdown from that value before switching fuel tanks. In other embodiments, a pilot may also use a countup sequence from zero in the fuel mode then stop the counter by depressing the start/stop button  42 , and switch fuel tanks. The time counted up will have been stored and the pilot may then count down from that stored value while operating on the opposite fuel tank by depressing the start/stop button a second time. 
   In each of the countdown modes in both the fuel timer mode and approach time modes, the counter can be configured to automatically count up after reaching zero, thereby displaying an overrun time for a user to view. Also, in each of these modes, the alarm  72  can be configured to be engaged when a countdown sequence reaches zero. Furthermore, in each of these modes, the alarm can comprise simultaneous audible and visible alarms, wherein a backlight of the LCD  40  will flash and wherein at least some characters on the display will also flash, whether or not the user has selected a different application mode than the application mode in which the alarm point has been reached. These alarm configurations can be substantially analogous to the alarm configuration described for the approach mode, supra, with the flashing indicator being the corresponding indicator for the application mode in which the alarm point has been reached. Alternatively, in other embodiments, the alarm can comprise various combinations of visible or audible alarms or consist only of a visible alarm or audible alarm. 
   The user may select a third application mode, the chronograph mode, by depressing button  4 . In some embodiments, the chronograph mode may be configured to have only a countup function and not a countdown function. In some embodiments the button  4  will need to be depressed twice to select the chronograph mode. Once chronograph mode is selected, the display position  14  is active, showing the “CHRONO” indicator. Also, display positions  26 ( 26   a ,  26   b ),  28  ( 28   a ,  28   b ) and  30  ( 30   a ,  30   b ) are active. In the chronograph mode, those positions display minutes, seconds and hundredths-of-a-second respectively until after 59 minutes, 59 seconds, and 99 hundredths-of-a-second, whereby the positions then display hours, minutes and seconds. The countup sequence in the chronograph mode is started by depressing the start/stop button  42  and ended by doing the same. The reset button can be depressed to restart the countup sequence from zero. 
   The fourth mode, the clock mode, can be selected by depressing button  6 . This activates display position  16  indicating “CLOCK.” Also, display positions  26  ( 26   a ,  26   b ),  28  ( 28   a ,  28   b ) and  30 ( 30   a ,  30   b ) are active, said display positions displaying hour, minute and second. The clock mode has three display modes configured for displaying standard time, military time and UTC time (time at the Royal Observatory in Greenwich, England). The clock button  6  can be depressed continuously to toggle between these three display modes. The clock can be set in each of the display modes in substantial accordance with the step diagram in  FIG. 10 . In yet further embodiments of the present invention, the dial  34  must be depressed and held down for a brief period of time, such as, for example, two (2) seconds, before a user is able to set a time of the clock using the dial  34 . 
   Some embodiments of the present invention also include a note function. The note function can be used to store and display information, including, without limitation, transponder code, future clearance altitude, cruising altitude, critical approach altitude, radio frequencies and other numeric data. It is displayed at position  8  in the LCD  40  of the illustrated embodiment, comprising eight (8) characters. The note can be set by depressing the dial  34  to activate setting mode for the thousands place numbers (two far left characters), then rotating the dial  34  to select those numbers, followed by sequentially depressing dial  34  and rotating dial  34  to select numerical settings for each remaining individual numerical position. 
   In the illustrated embodiments in  FIGS. 1 and 2 , a backlight button  36  and lighting element (not shown) is provided to illuminate the LCD when the backlight button is depressed. The backlight can then be switched off by depressing the backlight button  36  a second time. In some embodiments, the backlight will automatically be shut off after five (5) minutes to preserve battery life if the user fails to shut it off. In other embodiments, the backlight can stay on for longer or shorter period of time before automatically shutting off. In still further embodiments, a shutoff time for the backlight can be programmed into the flight timer  1  by a user. 
   As best seen in  FIGS. 3 and 4  the present invention can include an attachment member  48 , such as a clip, for attaching the flight timer  1  to a belt, clipboard, or other surface. The attachment member  48  can be rotatable about a mounting axis to allow flexibility in positioning the flight timer  1  with relation to a surface to which the attachment member  48  is coupled, such as, for example, the long side of a clipboard. A releasable locking mechanism  50  can be provided to help retain the attachment member  48  in a rotated position, such as, for example, detents  50 . 
   Although specific embodiments and examples of the invention have been described supra for illustrative purposes, various equivalent modifications can be made without departing from the spirit and scope of the invention, as will be recognized by those skilled in the relevant art after reviewing the present disclosure. The various embodiments described can be combined to provide further embodiments. The described devices and methods can omit some elements or acts, can add other elements or acts, or can combine the elements or execute the acts in a different order than that illustrated, to achieve various advantages of the invention. These and other changes can be made to the invention in light of the above detailed description. 
   In general, in the following claims, the terms used should not be construed to limit the invention to the specific embodiments disclosed in the specification. Accordingly, the invention is not limited by the disclosure, but instead its scope is determined entirely by the following claims.