Patent Publication Number: US-8526272-B2

Title: Day and time chronometer movement

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation and claims the priority benefit of U.S. patent application Ser. No. 13/092,843 filed Apr. 22, 2011, which is continuation-in-part and claims the priority benefit of U.S. patent application Ser. No. 10/789,388, filed Feb. 28, 2004, the entireties of which are incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to chronometers and, more specifically, to a clock that displays a continuously moving day hand. 
     2. The Prior Art 
     Clocks and other types of chronometers have an ancient lineage. Some of the earlier clocks used peg and tooth gears in order to display hours and minutes somewhat accurately. More recently, many chronometers use gear trains of toothed gears to provide this feature. 
     Basic gears work on the principle that when two circles are turning with their edges at the same speed, their relative rotational speeds are a function of the difference in their circumference, which are, in turn, dependent upon their respective radii or diameters, through use of the equation C=2.pi.R (or C=.pi.D). Teeth around the edges of a circular gear are often utilized to eliminate slippage between the edges of the circular gears. This guarantees that the edges of the circular gears rotate at the same speed, and that torque from one gear to another is transferred without loss. One added feature of utilizing gears is that while the relative speed of the rotation of two intermeshing gears is based on the ratio of their respective diameters, the amount of torque transferred has an inverse ratio. Thus, if a first gear has 5 teeth around its circumference, and a second gear has 30 teeth similarly spaced around its circumference, the first gear will turn 6 times as fast as the first, but have ⅙ the torque. It should also be noted that since the edges are synchronized, the two gears rotate in opposite directions when engaged. 
     These features have long been utilized in clocks and other chronometers. Thus, a gear driving a minute hand and one driving an hour hand can be synchronized if the gear ratios between the two have a ratio of 60/1, and this can be accomplished utilizing a 5/1 and a 12/1 gear ratio or a 10/1 and a 6/1 gear ratio. 
     At one point in the past, gear trains consisting single gears that engaged and intermeshed were utilized in clocks and other chronometers. However, it was discovered that multiple gears could be fixably mounted on the same shaft, and that gear trains so constructed were simpler to construct and often easier to design and took up less space. Many mechanical clocks today utilize this feature, with most of their gears in their gear trains being constructed utilizing multiple gears mounted on common shafts, and with some of those shafts being utilized to drive the hands of the chronometers. 
     Many, if not most, mechanical or partially mechanical clocks and other chronometers today operate by having a drive gear that operates at a fairly high constant speed. Thus, a drive gear being driven by 120 cycle current in the U.S. would typically rotate 120 times per second. This rotation would be stepped down to 1 cycle or revolution per second for a “Second” gear through use of a set of gears providing a 120/1 gear ratio. The “Second” gear could then be stepped down to a “Minute” gear through use of a set of gears providing a 60/1 gear ratio, and an “Hour” gear through use of a set of gears again providing a 60/1 gear ratio. Attaching the “Hour”, “Minute”, and “Second” gears to hollow shafts of differing sizes, inserting one of these shafts into another, and then attaching hands to the these shafts, provides the familiar clock or watch face with hour, minute, and second hands rotating around a common center. 
     While clocks and other chronometers have long been capable of displaying hours, minutes, and seconds, chronometers displaying days of the week are much less common. One problem that has been difficult to solve is that of setting the day of the week. When setting, in particular, the hour and minute, it is common for clocks and other chronometers to provide this feature by manually rotating the minute hand completely for each hour that needs to be changed. Thus, in order to adjust the time forward by 2 hours and 15 minutes, one might rotate the minute hand around the dial 21/4 times. While laborious, this has long been considered acceptable overhead, given that clocks rarely need to be adjusted that much. But that approach does not work well when adopted to adjusting a day hand, because in order to adjust the day and time ahead by 3 days 2 hours and 15 minutes, one would need to rotate the minute hand 741/4 times (3*24+2+¼) around the clock face. This is one of the reasons that Day hands have not been seen in the past that were driven directly and continuously off of a gear train that also directly and continuously drives the Hour, Minute, and Second hands. Rather, chronometers that display the day of the week typically utilize some type of ratchet system, where the Day hand is effectively decoupled from the Hour, Minute, and Second gears. 
     It would thus be advantageous for there to be a mechanical clock utilizing a gear train that continuously drives a day hand at a constant speed utilizing the same gear train that drives hour and minute hands at a constant speed. 
     BRIEF SUMMARY OF THE INVENTION 
     This patent discloses and claims a useful, novel, and unobvious invention for a clock with a continuously moving day hand in the chronometer field. 
     A day clock has day, hour, and minute hands revolving continuously around a common center. It has a time adjustment knob and a day adjustment knob. When the day adjustment knob is pulled out, a set of gears are disengaged, allowing the day hand to be adjusted with that knob without affecting the other hands. Then, when the set of gears are reengaged, the time adjustment knob can be utilized to set the time of day. In order to set the day and time accurately, the user may first set the time to midnight with the time adjustment knob, pull out the day adjustment knob, set the day to a clock face line between days with that knob, push that knob back in, and then set the time to the correct time with the time adjustment knob. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front view of a day clock, in accordance with one embodiment of the present invention; 
         FIG. 2  is a rear perspective view of the day clock shown in  FIG. 1 ; 
         FIGS. 3-8  are top views of the movement with gear assemblies progressively added to show the structure of the gear assemblies within the movement; 
         FIGS. 9A and 9B  are side sectional views of the embodiment shown in  FIGS. 1 and 2 ; 
         FIGS. 10A and 10B  are rear perspective views of the movement shown in  FIGS. 1 and 2 ; 
         FIGS. 11A and 11B  are rear perspective views of the movement shown in  FIGS. 1 and 2 ; and 
         FIG. 12  is a flowchart illustrating a setting of day and time, in accordance with one embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     A Day Clock is a clock that displays the day of the week, along with possibly the hour, minute, and second. In this invention, the Day, Hour, Minute, and Second hands are mounted on concentric shafts, so that these hands can rotate simultaneously and continuously around a common center. A Time Adjustment Knob and a Day Adjustment Knob are provided. Pulling out the Day Adjustment Knob disengages the gears driving the Day hand from the gears driving the other hands. The Day hand can then be adjusted independently of the other hands utilizing this knob. This knob is then pushed in, reengaging the gears, allowing the Day hand to move along with the other hands, and to be adjusted along with the other hands by the Time Adjustment Knob. 
     In the following disclosure, multiple gears are most often mounted on a common shaft on what will be termed herein as a “gear assembly”. A gear assembly will have one, two, or possibly more gears fixably attached to a common shaft, which may be solid or hollow, and may or may not be fixably attached to a longer shaft utilized to turn the clock hands or be turned by someone adjusting the day or time. In the embodiments of the present invention disclosed below, “Day”, “Hour”, “Minute”, and typically “Second”, gear assemblies are stacked, one on top of another, with each one having a long shaft, with those shafts inserted into each other, allowing the various hands to rotate around a common center. 
     When gears intermesh, engage, and interoperate, there is typically a “driving” gear and a “driven” gear. The “driving” gear transfers rotational torque to the “driven” gear. A “gear train” is a set or system of gears arranged to transfer rotational torque from one part of a mechanical system to another. In this disclosure, the term “gear train” is utilized to identify the set of interworking gears and gear assemblies between an initial driving gear to the gear assembly turning the day hand  12 . The gear assemblies with multiple gears in the gear train are described below from the Day hand back to the driving gear. They will be describe however from the point of view of a “driving” and a “driven” gear. A “driving” gear provides rotational torque to a “driven” gear below it on the gear train. The original “driving” gear typically gains its torque and rotational speed from an electro-mechanical device such as an oscillator. 
     In this description, the “Second” gear will be the driving gear for the next gear in the gear train, and the “First” gear will be the driven gear, driven by the “Second” gear of the previous gear in the gear train. In the FIGs., the gear assembly themselves will be given a reference number without a suffix. The “First” (driven) gear will be given the suffix of “A”, and the “Second” (driving) gear will be given the suffix of “B”. Thus, for the second “Day” gear, the gear assembly is designated as “ 32 ”, with the “First” (driven) gear being designated as “ 32 A” and the “Second” (driving) gear being designated as “ 32 B”. It should be understood that this identification is solely for the purpose of description, and has no relevance to the functionality or structure of the claimed and disclosed invention. Also, in the situation of the initial driving gear and the Time Adjustment mechanism, there will not be shown a “driven” gear, and thus no “First” (driven) gear (with an “A” suffix). Similarly, the gear assembly that turns the Hour hand will not be shown having a “Second” (driving) gear (with a “B” suffix), since it is at the end of the gear train. 
       FIG. 1  is a front view of a day clock  10 , in accordance with one embodiment of the present invention. The day clock  10  has a circular face and is shown with three hands rotating around a common center: a Day hand  12 , an Hour hand  14 , and a Minute hand  16 . In other embodiments, a Second hand (not shown) is also incorporated. The outside of the face of the clock  10  is traditional, with, for example, hours  15  being designated and displayed in regular intervals around the circumference of the clock  10  face. Within the outer circumference of the clock face  10  with the digits for hours  15 , are the names of the typically 7 days of the week  13  spaced evenly around the face of the clock. Also shown on the face of the clock are lines  11  separating the days of the week. In a preferred embodiment, with a 7 day week, there will be one line extending from the center of the clock with the hands  12 ,  14 ,  16 , downward, and the remainder of these lines will be positioned accordingly. These lines typically identify mid-night, and can be used to quickly and accurately adjust the hands on the clock. 
       FIG. 2  is a rear perspective view of the day clock  10  shown in  FIG. 1 . A movement  20  (shown as dashed lines in  FIG. 1 ) drives the hands  12 ,  14 ,  16  of the clock. The movement  20  is powered by a battery  24 , and has a Time Adjustment Knob  26  and a Day Adjustment Knob  28 . 
       FIGS. 3-8  are top views of the movement  20  with gear assemblies progressively added to show the structure of the gear assemblies within the movement  20 .  FIG. 3  shows a second Hour gear assembly  34  engaging a first Hour gear assembly  36 .  FIG. 4  shows a second Minute gear assembly  38  engaging and driving the first Hour gear assembly  36 .  FIG. 5  shows the first Hour gear assembly  36  and a second Minute gear assembly  38 , which engages and is driven by a first Minute gear assembly  40 .  FIG. 6  shows the first Minute gear assembly  40  engaging and being driven by a second Second gear assembly  42 .  FIG. 7  shows the first Minute gear assembly  40  and second Second gear assembly  42  installed on a mounting block  48 . Also shown is a driving gear  46  engaging and driving a first Second gear assembly  44 , which, in turn, engages and drives the second Second gear assembly  42 .  FIG. 8  shows the top of the movement  20  with the top and Time Adjustment Knob  26  and Day Adjustment Knob  28  attached. Shown as dashed lines within the movement  20  are a first Day gear assembly  32 , first Minute gear assembly  40 , second Second gear assembly  42 , first Second gear assembly  44 , driving gear assembly  46 , and mounting block  48 . 
       FIGS. 9A and 9B  are side sectional views of the embodiment shown in  FIGS. 1 and 2 .  FIG. 9A  shows the movement with the day adjustment feature not engaged, and  FIG. 9B  shows the same view with the day adjustment feature engaged. As noted above, the description of the movement is from the gear driving the Day hand  12  back to an initial driving gear  46 . Dotted lines show the drive gear train from a first Second gear assembly  44  to a Day hand shaft  52 . Note that when the day adjustment feature is engaged, and the Day hand is disengaged from the clock&#39;s gear train, the drive gear chain stops at the point where the gears for the Day hand are disengaged from the remainder of the gear chain. 
     In this embodiment, the movement  20  case is constructed of plastic, and consists of three parts or sections. A lower part  21  contains primarily Day gear assemblies  30 ,  32 . The lower part  21  is permanently attached to a middle part  22 . A removable top part  23  snaps onto the middle part  22 , and in the interior thus formed are mounted the remainder of the gear assemblies, as well as the electro-mechanical driver, which in this embodiment is a battery  24  operated oscillator (not shown). The bottom of the top part  23  is formed to hold the gear assemblies in place. The battery  24  fits in a separate compartment in the middle part  22 , and is covered by a removable cap (not show), allowing for easy replacement of the battery  24 . 
     The Day hand  12  is attached to a “Day” hand shaft  52  that is fixably connected to a second Day gear assembly  30  in the lower part  21  of the movement  20  case. Fixably attached to the second Day gear assembly  30  is a Day hand shaft  52 , upon which the Day hand  12  is mounted. The second Day gear assembly  30  has a first gear  30 A that engages and is driven by a second gear  32 B of a first Day gear assembly  32 . The first Day gear assembly  32  has a first gear  32 A that selectively engages and is driven by a second gear  34 B of a second Hour gear assembly  34 . The second Hour gear assembly  34  is fixably connected to an Hour hand shaft  54  upon which an Hour hand  14  may be mounted. The Hour hand shaft  54  is inserted into the Day hand shaft  52 . In this embodiment, the product of the ratios between gears  32 B/ 30 A and  34 B/ 32 A will typically be 24*7=168, so that the Hour hand  14  rotates 24 times for each time that the Day hand rotates to the next day. Since there are 7 days in a week, this means that the Day hand  12  rotates around the clock face at a rate of approximately 2.143.degree. per hour (360/168), while the Hour hand  14  rotates around the clock face at a rate of 360.degree. per hour. 
     The second Hour gear assembly  34  has a first gear  34 A which engages and is driven by a second gear  36 B of a first Hour gear assembly  36 . The first Hour gear assembly  36  has a first gear  36 A that selectively engages and is driven by a second gear  38 B of a second Minute gear assembly  38 . The second Minute gear assembly  38  is fixably connected to a Minute hand shaft  56  upon which a Minute hand  16  may be mounted. The Minute hand shaft  56  is inserted into the Hour hand shaft  54 . In this embodiment, the product of the ratios between gears  36 B/ 34 A and  38 B/ 36 A will typically be 60, so that the Minute hand  16  rotates 60 times for each time that the Hour hand  14  rotates to the next hour. 
     The second Minute gear assembly  38  has a first gear  38 A which engages and is driven by a second gear  40 B of a first Minute gear assembly  40 . The first Minute gear assembly  40  has a first gear  40 A that selectively engages and is driven by a second gear  42 B of a second Second gear assembly  42 . The second Second gear assembly  42  may be fixably connected to a Second hand shaft  58  upon which a Second hand (not shown) may be mounted. The Second hand shaft  58  may be inserted into the Minute hand shaft  56 . In this embodiment, the product of the ratios between gears  40 B/ 38 A and  38 B/ 36 A will typically be 60, so that the Second hand rotates 60 times for each time that the Minute hand  16  moves to the next minute. 
     The second Second gear assembly  42  has a first gear  42 A which engages and is driven by a second gear  44 B of a first Second gear assembly  44 . The first Second gear assembly  44  has a first gear  44 A that selectively engages and is driven by a second gear of a driving gear assembly  46  (better shown in  FIG. 8 ). The driving gear assembly  46  is typically driven by a rotational source that advances the teeth of the second gear at a specified rate. In the case of a clock attached to 120 cycle electricity, the driving gear will thus rotate 120 times a second. The gear ratios between the driving gear  46 , the first Second gear assembly  44  gears, and the second Second gear assembly  42  first gear  42 A will depend on the rotational speed of the driving gear  46 . In this embodiment, the driving gear  46  is driven by an electro-mechanical device (not shown) powered by a battery  24 . 
     Also, in this embodiment is shown a Time Adjustment Knob  26  coupled by a shaft  27  having a second (driving) gear  27 B. This engages the first gear  36 A of the first Hour gear assembly  36 , allowing the minutes and hours to be adjusted by rotating the first Hour gear assembly  36  in a forward or reverse direction. 
     Also shown in this embodiment is a Day Adjustment Knob  28  which is connected by a shaft  29  to the first Day gear assembly  32 . Pulling the Day Adjustment Knob  28  out and pushing it in allows the first Day Gear assembly  32  to selectively disengage and engage with the second gear  34 B of the second Hour gear assembly  34 .  FIG. 9A  shows the Day Adjustment Knob  28 , shaft  29 , and first Day gear assembly  32  in a depressed, lowered, and engaged position.  FIG. 9B  shows the Day Adjustment Knob  28 , shaft  29 , and first Day gear assembly  32  in a raised and disengaged position. When an operator pulls the Day Adjustment Knob  28  out, the first gear of the first Day gear assembly  32  is raised above the second gear  34 B of the second Hour gear assembly  34 , disengaging the two gears  33 . In this position, rotating the Day Adjustment Knob  28  acts to rotate the second Day gear assembly  30 , attached Day hand shaft  52 , and Day hand  12 , without rotating any of the gear assemblies above in the gear train. Then, when the operator pushes the Day Adjustment Knob  28  back in, the first Day gear assembly  32  descends, and the first gear  32 A of the first Day gear assembly  32  engages  33  the second gear  34 B of the second Hour gear assembly  34 , and allows the Hour hand  14  to be driven by the drive train, along with the other hands  14 ,  16 . 
       FIGS. 10A and 10B  are top perspective views of the movement shown in  FIGS. 1 and 2 .  FIGS. 11A and 11B  are bottom perspective views of the movement shown in  FIGS. 1 and 2 . These FIGs. further illustrate the operation of engaging and disengaging the Hour hand portion of the gear train in order to adjust the Day without adjusting the Time.  FIGS. 10A and 11A  show the first gear  32 A of the first Day gear assembly engaged with the second gear  34 B of the second Hour gear assembly  34 , when the Day Adjustment Knob  28 , shaft  29 , and first Day gear assembly  32  are in an lowered position as a result of a user pushing down on the Day Adjustment Knob  28 .  FIGS. 10B and 11B  show the first gear  32 A of the first Day gear assembly disengaged  33  from the second gear  34 B of the second Hour gear assembly  34 , when the Day Adjustment Knob  28 , shaft  29 , and first Day gear assembly  32  are in a raised position as a result of a user pulling out or up on the Day Adjustment Knob  28 . 
     It should be understood that the above day clock  10  and movement  20  is exemplary, and others are also within the scope of the present invention. For example, a second hand may be included, and if included, a Second hand shaft  58  would typically be fixably attached to a Second gear assembly  42 ,  44 . On the other hand, the Second hand and Second hand shaft  58  may be omitted, and if so, then there is no requirement that one of the Second gear assemblies be stacked above the Minute, Hour, and Day gear assemblies. 
       FIG. 12  is a flowchart illustrating a setting of day and time, in accordance with one embodiment of the present invention. In order to set the day and time utilizing the present invention, one may start with the Day Adjustment Knob  28  depressed, with the Day gear assemblies  30 ,  32 , fully engaged with the remainder of the gear train, step  61 . One could then adjust the time of day to noon or midnight (the same on most clocks), step  62 . Next, one could pull out the Day Adjustment Knob  28 , disengaging the Day gear assemblies  30 ,  32 , from the rest of the gear train, step  63 . Next, the day of the week could then be adjusted by rotating the Day Adjustment Knob  28 , step  64 . Preferably, the adjustment of the Day hand  12  is to one of the lines  11  displayed on the front of a day clock  10 . The lines  11  typically represent midnight between two days. Then, the Day Adjustment Knob  28  is depressed, step  65 , engaging the Day gear assemblies  30 ,  32 , and Day hand  12  with the rest of the gear train. Finally, the time can be adjusted utilizing the Time Adjustment Knob  26 , step  66 . One advantage of this method, in conjunction with the clock  10  with movement  20  disclosed above, is that it is easy to identify whether a specific time is AM or PM by the position of the Day hand  12 . It should be understood that this method is exemplary, and other methods are also within the scope of the present invention. 
     Those skilled in the art will recognize that modifications and variations can be made without departing from the spirit of the invention. Therefore, it is intended that this invention encompass all such variations and modifications as fall within the scope of the appended claims.