Patent Publication Number: US-2004052162-A1

Title: Mechanical chronograph timepiece

Description:
BACKGROUND OF THE INVENTION  
       [0001] The present invention relates to a mechanical chronograph timepiece.  
       [0002] The fact is known that a minute-counting hand and a second-counting hand are returned (reset) to their initial positions by using a hammer having a base portion side arm portion, and a minute-counting hand reset arm portion and a second-counting hand reset arm portion, which are bifurcated at a tip of the base portion side arm portion. As to this kind of hammer, it is constituted such that the minute-counting hand and the second-counting hand are reset by supporting, by means of a turning axle, a base end portion of the base portion side arm portion of the hammer so as to be capable of turning and, by a turn biasing force of a hammer spring, colliding each of tip portions of the respective minute-counting hand reset arm portion and the second-counting hand reset arm portion against corresponding hearts, i.e., minute heart and second heart, thereby returning each of the hearts to its initial position.  
       [0003] In this kind of mechanical chronograph timepiece, the fact itself is also known that, in view of various manufacture tolerances and the like, a size of a gap between the tip portion of the minute-counting hand reset arm portion and the minute heart is made adjustable such that the gap becomes sufficiently small under a state that the tip portion of the second-counting hand reset arm portion butts against the second heart. For the adjustment of this gap, in a conventional mechanical chronograph timepiece, a manner or degree of a deformation of the hammer has been adjusted, i.e., a relative position of the tip portion of the minute-counting hand reset arm portion with respect to the tip portion of the second-counting hand reset arm portion has been changed/adjusted, by forming a circular hole in a root of the bifurcated portion, i.e., tip portion of the base portion side arm portion, of the hammer, forming in a circumferential face of the hole a slit connecting the hole and the bifurcated portion, driving a non-columnar pin whose section is an elliptic shape into the circular hole, and additionally turning the non-columnar pin in the circular hole to thereby change/adjust an opening degree of the slit.  
       [0004] However, since the hammer has a rigidity necessary for mechanically returning each heart to its initial position by the fact that each chronograph hand reset arm portion collides against the corresponding heart under an action of the hammer spring, it consists of a material body whose rigidity is comparatively high, such as an iron-based material, so that not only the driving itself of the non-cylindrical pin is not necessarily easy but also it is not easy to rotate the non-columnar pin in a predetermined direction against the rigidity of the hammer. Further, not only it is necessary to provide an expanding slot leading to a hole of an inner part of the bifurcated portion of the hammer but also it is necessary to separately provide an eccentric pin, so that not only structures of parts are complicated but also it is necessary to ensure a space for driving the pin and a space for allowing a free rotation of the bifurcated portion into which the pin has been driven.  
       [0005] The present invention was made in view of the points mentioned above, and its object is to provide a mechanical chronograph timepiece in which an adjustment of a hammer position can be easily performed.  
       SUMMARY OF THE INVENTION  
       [0006] In order to achieve the above object, a mechanical chronograph timepiece of the present invention has a hammer support means setting a basic center axis, an eccentric means which is mounted to the hammer support means, which sets an adjustment center axis that is eccentric with respect to the basic center axis of the support means, and in which a direction of an eccentricity of the adjustment center axis with respect to the basic center axis is adjustable, a hammer possessing a base portion side arm portion supported by an eccentric means so as to be capable of turning about the adjustment center axis at a base end portion and two kinds of chronograph hand reset arm portions bifurcated/extended from a tip portion of the base portion side arm portion, and hearts which are respectively capable of returning to their initial positions when pressed by tip portions of the chronograph hand reset arm portions and which are respectively attached to corresponding kinds of chronograph hands.  
       [0007] In the mechanical chronograph timepiece of the present invention, since there is provided “an eccentric means which is mounted to the hammer support means, which sets an adjustment center axis that is eccentric with respect to the basic center axis of the support means, and in which a direction of an eccentricity of the adjustment center axis with respect to the basic center axis is adjustable”, by adjusting the direction of the eccentricity by operating this adjustable eccentric means, it is possible to adjust initial positions of the two kinds of chronograph hand reset arm portions of the hammer and, by this, initial positions of two kinds of hearts set in compliance with the initial positions of the two kinds of chronograph hand reset arm portions can be adjusted. Accordingly, since it suffices if a position of the hammer is adjusted by attaching the hammer to the hammer support means at an approximate position through the eccentric means and thereafter adjusting the direction of the eccentricity of the eccentric means, no special skill and experience are required for the attachment of the hammer, so that a low cost and rapid assembling becomes possible and also an accurate positioning of the hammer can be easily performed.  
       [0008] The two kinds of chronograph hands are typically any two among “hour-counting hand”, “minute-counting hand” and “second-counting hand”. In case where a precise position of one chronograph hand among the two can be set by a jumper engaging with teeth of a gear wheel integral with the chronograph hand, it suffices if, when the corresponding reset arm portion of the hammer is positioned with respect to the heart becoming integral with the other chronograph hand, a gap between the heart integral with the one chronograph hand and the corresponding reset arm portion of the hammer is adjusted by the eccentric means such that a play owing to the gap becomes less than a unit rotation angle of the gear wheel. The two kinds of chronograph hands are typically the second-counting hand and the minute-counting hand. However, if desired, they may be other combination. In case where reset positions of the second- and minute-counting hands are adjusted, as to the second-counting hand whose deviation in reset position is liable to be especially conspicuous, a state that the corresponding reset arm portion of the hammer and the second heart are butted is made an initial position and the second-counting hand is attached to a second-counting arbor made integral with the second heart while being agreed with a direction of a corresponding dial in the initial position, and a reset position of the minute-counting hand is gap-adjusted by the eccentric means. However, in such a case that a second-counting gear wheel is accompanied by a jumper, if desired it may be adapted such that the reset position of the second heart relating to the second-counting hand is determined by a gap adjustment by the eccentric means.  
       [0009] In the mechanical chronograph timepiece of the present invention, typically, the eccentric means is fitted to the hammer support means so as to be capable of turning about the basic center axis, and the base portion side arm portion of the hammer is fitted to the eccentric means so as to be capable of turning about the adjustment center axis. The hammer support means setting the basic center axis may be an axle or a bearing or hole setting means for receiving the axle, and similarly the eccentric means setting the adjustment center axis may be an axle or a bearing or hole setting means for receiving the axle.  
       [0010] Here, a diameter of the portion, in the eccentric means, fitted to the hammer support means is smaller than a diameter of the portion, in the eccentric means, fitted to the base portion side arm portion of the hammer. However, if desired, it may be the same degree or larger.  
       [0011] In this case, in the mechanical chronograph timepiece of the present invention, for example, even if the hammer support means has a columnar center axle which is supported by the main plate and whose center is the basic center axis and the eccentric means has an eccentric bush fitted to the center axle by its cylindrical inner peripheral face and possessing an outer peripheral face that is eccentric with respect to the inner peripheral face, the hammer support means may include the main plate possessing a cylindrical hole whose center is the basic center axis, and the eccentric means may have a base portion side columnar portion fitted to the cylindrical hole of the main plate and a lever side columnar portion which is formed in one end side of the base portion side columnar portion and which is eccentric with respect to the base portion side columnar portion.  
       [0012] In the mechanical chronograph timepiece of the present invention, typically, an engaged portion extending substantially in a diameter direction with respect to a reference center axis is formed in a surface of the eccentric means such that a direction of an eccentricity by the eccentric means can be adjusted.  
       [0013] In that case, by rotating the engaged portion by engaging an engaging portion such as a tool&#39;s tip with it, the direction of the eccentricity can be adjusted easily and accurately. Here, the engaged portion consists of a groove extending in the diameter direction for instance. However, the engaged portion may be formed in a circumferential face of the eccentric means in place of its end face. In that case, the engaged portion consists of a roughened circumferential face region for instance.  
       [0014] In the chronograph timepiece of the present invention, typically, for example, the hammer support means has a columnar center axle which is supported by a main plate and whose center is the basic center axis, and the eccentric means has an eccentric bush which is fitted to the center axle by a cylindrical inner peripheral face and which possesses an outer peripheral face that is eccentric with respect to the inner peripheral face. In that case, the direction of the eccentricity can be adjusted only by rotating the eccentric bush with respect to the center axle. In that case, typically, the eccentric bush has a flange-like portion, and an engaged groove extending substantially in the diameter direction with respect to the reference center axis is formed in a surface of the flange-like portion. In this case, the rotation of the eccentric bush can be easily performed and the adjustment of the direction of the eccentricity is easy, nevertheless such a fear is few that the eccentric bush itself is rotated with respect to the center axle with the rotation of the hammer or the like. However, in order to avoid such a fear that the eccentric bush position-deviates (the direction of the eccentricity changes) with respect to the center axle after the eccentric bush has been positioned with respect to the center axle, preferably there is provided a securing means for fixing the eccentric bush to the center axle. As this securing means, a screw is used for instance. However, it may be whatever other securing means.  
       [0015] In the mechanical chronograph timepiece of the present invention, typically, the chronograph hands include a second-counting hand and a non-second-counting hand, and when a tip portion of, in the hammer, one chronograph hand reset arm portion corresponding to a second heart butts against the second heart and thus is in a state that it returns the second heart to its initial position, a relative position between a tip portion of, in the hammer, the other chronograph hand reset arm portion corresponding to a non-second heart and the non-second heart in its returned position is adjusted in compliance with the direction of the eccentricity of the eccentric means.  
       [0016] Incidentally, such a mechanical chronograph timepiece as mentioned above is typically incorporated into a watch. In this case, the watch typically consists of an analog watch but, if desired, a hand movement controlling portion may be an electronic timepiece. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0017] A preferred embodiment of the invention will now be described with reference to the accompanying drawings wherein:  
     [0018]FIG. 1 is a plan explanatory view showing a non-operating state (or reset state), i.e., normal hand movement state, about a chronograph mechanism of a timepiece of one preferred embodiment according to the present invention (XII and III respectively indicate a 12 o&#39;clock direction and a three o&#39;clock direction);  
     [0019]FIG. 2 is an enlarged plan explanatory view about a hammer and related parts for adjusting its eccentric position in the chronograph mechanism of FIG. 1;  
     [0020]FIG. 3 are sectional views (sectional views along approximately IIIA-IIIA line in FIG. 2) shown while being enlarged, wherein FIG. 3A is a sectional explanatory view, and FIG. 3B and FIG. 3C similar sectional explanatory views respectively about modified examples;  
     [0021]FIG. 4 is a graph schematically showing a relation between a turning position of an eccentric bush and a size of a gap between faces of a minute heart and a hammer in the chronograph mechanism of FIG. 2;  
     [0022]FIG. 5 is a front explanatory view of one example of a timepiece possessing the chronograph mechanism of FIG. 1;  
     [0023]FIG. 6 is a plan explanatory view showing a start state, of a chronograph motion, about the chronograph mechanism of FIG. 1; and  
     [0024]FIG. 7 is a plan explanatory view showing a stop state, of the chronograph motion, about the chronograph mechanism of FIG. 1. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0025] Some of preferred implementation modes of the present invention are explained on the basis of preferred embodiments shown in the attached drawings.  
     [0026] A watch possessing a chronograph timepiece of one preferred embodiment according to the present invention has such an external appearance as shown in FIG. 5 for instance. A watch  1  functions as a usual analog wristwatch  2  giving a usual time indication, and functions as a chronograph timepiece  3  giving an elapsed time indication as a stopwatch, i.e., a chronograph indication. That is, the watch  1  has an hour hand  11 , a minute hand  12  and a second hand  13  as well as corresponding dial portions  10  and  14 , which give the time indication in the occasion of a usual hand movement, and a chronograph hour hand or hour-counting hand (hereafter referred to as “hour-counting hand”)  16 , a chronograph minute hand or minute-counting hand (hereafter referred to as “minute-counting hand”)  17  and a chronograph second hand or second-counting hand (hereafter referred to as “second-counting hand”)  18  as well as relating dial portions  15  and  19 , which give a chronograph time indication in the occasion of a chronograph timepiece motion. That is, in this example, the time indication by the hour hand  11  and the minute hand  12  in the occasion of the usual hand movement is performed by the large dial portion  10 , and the time indication by the second hand  13  is performed by the small dial portion  14 . On the other hand, the time indications by the hour-counting hand  16  and the minute-counting hand  17  in the occasion of a chronograph motion, i.e., stopwatch motion, are performed respectively by the corresponding dial portions  15  and  19 , and the time indication by the second-counting hand  18  is performed by the large dial portion  10 . Incidentally, in this example, a chronograph minute timer is made a thirty-minute timer. In FIG. 5, “III” and “XII” point to respectively three o&#39;clock and twelve o&#39;clock directions with respect to the dial  10 .  
     [0027] The chronograph timepiece  3  has additionally a start/stop button  4  and a reset button  5 . As to the chronograph timepiece  3  of the watch  1 , in case where it is performing a usual hand movement motion, usually the hour-counting hand  16 , the minute-counting hand  17  and the second-counting hand  18  exist respectively in initial positions. In the chronograph timepiece  3 , if the start/stop button  4  is pressed in an A1 direction, the hour-counting hand  16 , the minute-counting hand  17  and the second-counting hand  18  start a chronograph elapsed time or clocking motion. Incidentally, after being pressed the button  4  is returned to a protruded position in an A2 direction by a spring  55  mentioned later. In the chronograph timepiece  3 , if the start/stop button  4  is pressed again in the A1 direction, a chronograph elapsed time or clocking motion is stopped, and the hour-counting hand  16 , the minute-counting hand  17  and the second-counting hand  18  are stopped. Next, if the reset button  5  is pressed in a B1 direction, the hour-counting hand  16 , the minute-counting hand  17  and the second-counting hand  18  are reset, i.e., returned to zero, and returned respectively to the initial positions, i.e., zero positions. Incidentally, after being pressed the reset button  5  is returned to a protruded position in a B2 direction by a spring  86  mentioned later.  
     [0028] Since a usual analog wristwatch  2  itself for clocking is publicly known, hereunder it is explained on the basis of FIG. 1 to FIG. 4 about the chronograph timepiece  3  of such a watch  1  as mentioned above, moreover among others mainly about portions of the minute-counting hand  17  and the second-counting hand  18 , and concerning its chronograph mechanism  7 . In FIG. 1, “III” and “XII” respectively point to the three o&#39;clock and twelve o&#39;clock directions with respect to the dial  10  and a relating enclosure or case of FIG.5.  
     [0029] In FIG. 1, a second-counting wheel  20  has a second-counting arbor  21 , and a second-counting gear wheel  22  and a second heart  23  which are fixed to the arbor  21 , and is rotatable about a center axis C 1  of the second-counting arbor  21 . The second-counting hand  18  is attached to the second-counting arbor  21 .  
     [0030] The second-counting wheel  20  (more detailedly, the second-counting gear wheel  22 ; the same hereafter) can mesh with a second counter intermediate wheel  24  (more detailedly its gear wheel; the same hereafter). The second counter intermediate wheel  24  always meshes with a second wheel (not shown) of the usual second hand  13  (FIG. 5), of the analog wristwatch  2 , indicating a time and, usually, is always rotating with the hand movement.  
     [0031] A minute-counting wheel  30  has a minute-counting arbor  31 , and a minute-counting gear wheel  32  and a minute heart  33  which are fixed to the arbor  31 , and is rotatable about a center axis C 2  of the minute-counting arbor  31 . The minute-counting wheel  30  always meshes with a minute counter intermediate wheel  34  (more detailedly, its gearwheel). The minute-counting hand  17  is attached to the minute-counting arbor  31 . A minute-counting jumper  35  is elastically pressed at a setting portion  35   a  to a minute-counting gear wheel  32 , thereby setting a rotation of the minute-counting wheel  30 .  
     [0032] The chronograph mechanism  7  has a column wheel or pillar wheel  40  for supporting a start (start) and a stop (stop) of a chronograph motion and a returning-to-zero (reset) motion of the chronograph hand. The column wheel  40  is rotatable about its axis C 3 , posesses even number of ratchet teeth  41  in its circumferential face, and possesses in its end face drive teeth or pillars  42  protruding from the end face in every other one of the ratchet teeth  41 . A setting protrusion  45  of a tip of a column wheel jumper  44  fixed at its base end to a main plate  6  is elastically pressed to the ratchet teeth  41 . Incidentally, as to this embodiment, it is explained about a type in which the chronograph mechanism  7  has the pillar (column wheel)  40 , but the chronograph mechanism  7  may be other type such as a cam system in place of the pillar system.  
     [0033] An operating lever  50  integral with the start/stop button  4  (FIG. 2 or FIG. 5) is engageable with the ratchet teeth  41  of the columnar wheel  40  at an operating pawl portion  51 . The operating lever  50  has a button operation receiving portion  52  capable of butting against the start/stop button  4 , an elongate hole  53  loosely fitted to an operating lever support pin.  99  so as to be relatively movable in the A1 and A2 directions, and a spring receiver  54 . A tip  55   b  of an operating lever spring  55  fixed at its base end  55   a  to the main plate is locked to the spring receiver  54 . Accordingly, the operating lever  50  is movable in the A1 and A2 directions, and always undergoes a biasing force in the A2 direction by the operating lever spring  55 . If the operating lever  50  is pressed in the A1 direction, the operating pawl portion  51  of the operating lever  50  engages with the ratchet teeth  41  of the column wheel  40  to press it in the A1 direction, thereby rotating the column wheel  40  by for one pitch in an R31 direction under the setting of the jumper  44 . After being pressed in the A1 direction, the operating lever  50  is returned in the A2 direction by the spring  55 .  
     [0034] A stop lever  60  capable of turning about a center axis C 4  has, in a tip side edge of one arm portion  61 , a setting protrusion  62  engageable with the drive teeth or pillars  42  of the column wheel  40  and has, in an outside edge of the other arm portion  63 , a chronograph coupling spring butting edge portion  64 . Additionally, the arm  63  has, in its tip portion  65 , a chronograph coupling lever butting portion  66  and has, in the vicinity of the tip portion  65 , a concave portion  67  engaging with an hour chronograph coupling transmission lever operating pin  77   a . A setting portion  68  capable of being pressed to a circumferential face of the second-counting gear wheel  22  of the second-counting wheel  20  is branched/extended in an inside edge side of the arm portion  63 . Every time the column wheel  40  rotates for one pitch of the ratchet teeth  41 , the stop lever  60  adopts alternately a stop position (FIG. 1 or FIG. 2, etc.) where the setting protrusion  62  fits between the adjacent drive teeth  42 ,  42  and engage with them, and a stop releasing position (FIG. 6, etc.) where it butts against an outer peripheral face of the drive teeth  42 . In the stop position, the stop lever  60  turns in an R41 direction, and the setting portion  68  is pressed to the second-counting wheel  20 . In the stop releasing position, the stop lever  60  turns in an R42 direction, and the setting portion  68  separates from the second-counting wheel  20 , thereby allowing its rotation.  
     [0035] A chronograph coupling lever spring  80  capable of turning about a center axis C 5  has bifurcated lever spring portions, i.e., a stop lever spring portion  81  and a chronograph coupling lever spring portion  82 , and it is elastically pressed to the butting portion  64  of the stop lever  60  at the stop lever spring portion  81  to thereby apply a rotation biasing force in the R41 direction to the stop lever  60 , and is elastically pressed to an arm portion  71  of a chronograph coupling lever  70  at the chronograph coupling lever spring portion  82 .  
     [0036] The chronograph coupling lever  70  rotatable in R61 and R62 directions about a center axis C 6  has, in addition to the arm portion  71 , an arm portion  74  including bifurcated arm portions  72  and  73 . The arm portion  72  has an engaged convex portion  75   a  and a butting release concave portion  75   b  in a side edge of a tip vicinity, and rotatably supports the second counter intermediate wheel  24  at its tip portion.  
     [0037] A chronograph coupling transmission lever  76  is connected to the arm portion  73  of the chronograph coupling lever  70  so as to be capable of turning about a center axis C 7 , and the chronograph coupling transmission lever operating pin  77   a  is attached to an arm portion  77  of the chronograph coupling transmission lever  76  and is engaged with the engaging concave portion  67  of the stop lever  60 . An hour chronograph coupling lever operating pin  78   a  is attached to the other arm  78  of the chronograph coupling transmission lever  76 .  
     [0038] A hammer operating lever  84  is capable of turning about the center axis C 5  in R53 and R54 directions, capable of butting against the reset button  5  (FIG. 5) in an operation receiving portion  84   a , and engages with an engaged concave portion  85   a  of a hammer click  85  at an engaging protrusion portion  84   b . The hammer click  85  is capable of turning about a center axis C 8  of a turning axle  85   b  in R81 and R82 directions, and between the turning axle  85   b  and an inner edge locking portion  84   c  of the hammer operating lever  84  there is provided a hammer operating lever spring  86  applying a rotation biasing force in the R54 direction to the hammer operating lever  84 . An approximately U-shaped hammer operating lever spring  86  is embraced in its curved bottom portion of U by an inner edge portion  84   e  of an arm portion  84   d  of the hammer operating lever  84 . The hammer click  85  has an arc-like arm portion  87  of a shape capable of extending approximately along an outer periphery of a train of the drive teeth  42  of the column wheel  40 , and the arm portion  87  possesses in its inner peripheral edge a setting protrusion portion  87   a  engageable between the adjacent drive teeth  42 ,  42 , and possesses in its tip portion a hammer regulating protrusion portion  87   b  engageable with a hammer  90 .  
     [0039] Accordingly, as detailedly mentioned later, when the chronograph mechanism  7  is in its stop state, if the hammer operating lever  84  is turned in the R53 direction against a spring force of the spring  86  by the pressing of the reset button  5  in the B1 direction and presses the engaged concave portion  85   a  in the R81 direction at the engaging protrusion portion  84   b , as mentioned later the hammer regulating protrusion portion  87   b  of the hammer click  85  separates from the hammer  90  to thereby allow a reset motion by the hammer  90 , and the setting protrusion portion  87   a  of the hammer click  85  fits between the adjacent drive teeth  42 ,  42  of the column wheel  40 . On the other hand, as detailedly mentioned later when the chronograph mechanism  7  is in its reset state, if the column wheel  40  is rotated by for one pitch of the ratchet teeth  41 , the setting protrusion portion  87   a  of the hammer click  85  is turned in the R82 direction by the outer peripheral face of the drive teeth  42 , and the hammer regulating protrusion portion  87   b  returns the hammer  90  to a non-operating position with the turning of the arm portion  87  in the R82 direction.  
     [0040] Incidentally,  89   a  and  89   b  are respectively an hour hammer operating lever and an hour chronograph coupling lever concerning the hour-counting hand  16 . The hour hammer operating lever  89   a  capable of turning about a center axis C 91  starts a reset operation of the hour-counting hand  16  in compliance with the pressing of the reset button  5  similarly to the hammer operating lever  84  concerning the minute-counting hand  17  and the second-counting hand  18 , and is engaged with an operation protrusion portion  89   c  of the hour hammer operating lever  89   a  at an engaged concave portion  89   d . The hour chronograph coupling lever  89   b  capable of turning about a center axis C 92  is rotation-biased clockwise in FIG. 1, etc. at a spring portion  89   f  by a pin  89   e , and is engageable at an engaging protrusion  89   g  or  89   h  with the hour chronograph coupling lever operating pin  78   a  existing in a concave portion  89   j  between a pair of engaging protrusions  89   g ,  89   h . This reset mechanism and the like for the hour-counting hand  16  are similar to a mechanism described in JP-A-11-183653 Gazette, so that a detailed explanation is omitted here.  
     [0041] As shown in FIG. 1 to FIG. 3A, the hammer  90  has a base portion side arm portion  92  mounted to an axle structure body  100  at a bearing portion  91  of a base end side so as to be capable of turning, and a minute-counting hand reset arm portion  93  and a second-counting hand reset arm portion  94  which are bifurcated from a tip of the base portion side arm portion  92 , and always undergoes a turn-biasing force in an F direction by a hammer spring  96  at a spring receiving portion  95 . The minute-counting hand reset arm portion  93  has at its tip a reset face  93   a  capable of butting against a pair of minimum diameter prescribing portions  33   a  of the minute heart  33 , and the second-counting hand reset arm portion  94  has at its tip a reset face  94   a  capable of butting against a pair of minimum diameter prescribing portions  23   a  of the second heart  23 . Additionally, the hammer  90  possesses, in an inside edge of the base side arm portion  92 , an engaged step portion  97  (shoulder portion  97   a  capable of releasing the engagement) with which the hammer setting protrusion portion  87   b  of the hammer click  85  is engageable.  
     [0042] As shown in FIG. 3A, an axle structure body  100  has an eccentric bush  110  fixed by a securing screw  98  in addition to an operating lever support pin  99  as a hammer support means. The operating lever support pin  99  possesses a tip side small diameter axle portion  99   c  in addition to a base end portion  99   a  mounted to the main plate and a large diameter axle portion  99   b  loosely fitted to the elongate hole portion  53  of the operating lever  50 , and the eccentric bush  110  is fitted to the small diameter axle portion  99   c . The axle portions  99   a ,  99   b  may have the same diameter. The eccentric bush  110  has an eccentric cylindrical portion  113  possessing an outer peripheral side cylinder face  112  whose center axis is Q eccentric with respect to an inner peripheral side cylinder face  111  whose center axis is C and a brim or flange-like portion  114  extending outward from a tip of the eccentric cylindrical portion  113  in a diameter direction, and an engaged groove  115  extending approximately in the diameter direction with respect to the center axis C of the inner peripheral side cylinder face  111  is formed in a surface of the flange-like portion  114 . Incidentally, the bearing portion  91  of the hammer  90  is fitted to an outer peripheral face of the eccentric cylindrical portion  113  of the eccentric bush  110 .  
     [0043] Accordingly, a direction of the eccentricity of the eccentric bush  110  can be adjusted by turning the eccentric bush  110  about the center axis C of the pin  99  by engaging a tip of a small minus driver or the like with the engaged groove  115  of the eccentric bush  110  and, by this adjustment of the direction of the eccentricity, a position of the center axis, i.e., adjustment center axis Q, of the hammer  90  can be adjusted. Incidentally, in this example, a spacing between the basic center axis C and the eccentric or adjustment center axis Q is in the order of 0.05 mm. However, this spacing is one depending on shapes and lengths of the arm portions  93  and  94  of the hammer  90  or the like, and it may be larger or smaller.  
     [0044] More detailedly, in the example shown in FIG. 2, the groove  115  extends along an eccentric direction, of the eccentric center axis Q, coinciding with the center axis Q of the eccentric bush  110 , i.e., the center axis of the outer peripheral face  112  of the eccentric cylindrical portion  113  of the eccentric bush  110 . In case where the groove  115  exists in an intermediate position shown by imaginary lines  115   a  in FIG. 2, if the eccentric bush  110  is rotated about the center axis C in an R1 direction, gaps G between the tip face  93   a  of the minute-counting hand reset arm portion  93  of the hammer  90  and the minimum diameter prescribing portions  33   a ,  33   a  of the minute heart  33  are spread (under a condition that a second heart reset face  94   a  of the second-counting hand reset arm portion  94  butts against a face prescribed by the corresponding portions  23   a ,  23   a  of the second heart  23 ) and, if it is rotated in an R2 direction, the gaps G become narrow. In FIG. 4, this position corresponds to a position indicated by a point P 0 . A size of the gap G becomes minimum in case where the eccentric center axis Q deviates by an angle α=+α0 (where, a clockwise direction is made +) with respect to the basic center axis C with an imaginary line L 2 , which is parallel to an imaginary line L 1  connecting the rotation center axis C 1  of the second heart  23  and the rotation center axis C 2  of the minute heart  33  as shown by a solid line in FIG. 2 and which passes the center axis C, being made a reference (this angle α is +52 degrees in this example).  
     [0045] If the eccentric bush  110  is rotated in the R1 direction from a position shown by an imaginary line in FIG. 2, i.e., position corresponding to the point P 0  of the graph in FIG. 4, the gap G is increased in a positive direction of a sine curve S 0  in FIG. 4 and, if the eccentric bush  110  is rotated in the R2 direction, it follows that the gap G is decreased in a negative direction of the sine curve S 0  in FIG. 4. Incidentally, in FIG. 4, a sine curve S 1  shows a case of the eccentricity of a maximum tolerance, and a sine curve S 2  shows a case of the eccentricity of a minimum tolerance.  
     [0046] For example, in case where the gap G becomes “0” or when the related members are constituted by such size, shape and disposition as to be a line denoted by G 0  in FIG. 4, the G 0  is made so as to become plus/minus less than 0.5 minutes and, typically, it follows that the eccentric bush  110  is turned such that it becomes a position denoted by a solid line or its vicinity. However, in that case, it is necessary that a size of the gap G is less than plus/minus 0.5 minutes at a position of α=+α0 with the size of the gap G having no relation to a dimension of the tolerance, i.e., even in case of a line S 2 .  
     [0047] Accordingly, for a safety in designing, for example, in case where the gap G becomes “0” when the related members are constituted by such size, shape and disposition as to be a line denoted by G 1  in FIG. 4, it follows that the eccentric bush  110  is rotated such that the eccentric bush  110  adopts, between the position P 0  and the solid line position, a proper position (position where the gap G becomes sufficiently small (for example, smaller than about 30 μm)) where the tip face  93   a  of the minute-counting hand reset arm portion  93  of the hammer  90  is not pressed to the minute heart  33 .  
     [0048] Even if a play remains for the minute heart  33  in the R21 and R22 directions about the center axis C 2  because of a slight gap remaining between the minute heart, reset face  93   a  and the corresponding portions  33   a ,  33   a  of the minute heart  33 , a turning position of the minute-counting wheel  20  can be precisely positioned in minutes by the setting portion  35   a  of the minute counter jumper  35  engaging with teeth of the minute-counting gear wheel  22 , so that it suffices if the gap G is decreased to less than plus/minus 0.5 minutes by the eccentric bush  110 .  
     [0049] Incidentally, in place of fixing the eccentric bush  110  by the securing screw  98 , it may be adapted such that, as shown in FIG. 3B, the eccentric bush  110  is merely fitted to the small diameter columnar portion  99   c  of the support pin  99 .  
     [0050] Further, in place of forming the eccentric bush  110  separately from the support pin  99 , the eccentric bush  110  may be formed integrally with the support pin  99 . In that case, as shown in FIG. 3C for instance, by making a tip portion of the support pin  99   h  into a columnar portion  99   f  possessing an eccentric circumferential face  122  similarly to the outer peripheral face  112  of the eccentric cylindrical portion  113  of the eccentric bush  110 , the columnar portion  99   f  may be caused to function as an eccentric means. In that case, by forming a groove  125  in an end face  126  of the columnar portion  99   f , the pin  99   h  itself is made rotatable about the center axis C with respect to the main plate  6  and the like.  
     [0051] Incidentally, in the above, it has been explained about the example in which a portion of the tip portion side, in the support pin  99 , of the operating lever  50  for the start/stop is used intact also as a pin for giving the rotation center C of the eccentric bush  110  of the hammer  90 , but these two pins may not be disposed coaxially and may be separate pieces.  
     [0052] Next, concerning the chronograph mechanism  7  of the chronograph timepiece  3  of the watch  1  constituted as mentioned above, it is explained about a chronograph motion with an adjustment operation of reset position and a reset motion being made a center.  
     [0053] In a usual hand movement motion of the watch  1 , the chronograph mechanism  7  adopts such a reset state as shown in FIG. 1. Accordingly, an adjustment of the reset position of the chronograph mechanism  7  is performed under a state similar to this hand movement state except a point that a whole of the watch  1  is not assembled yet.  
     [0054] The adjustment of the reset position of the chronograph mechanism  7  is performed before an attachment of the securing screw  98  (FIG. 3A) and before an attachment of the second-counting hand  18 . Further, by rotating the eccentric bush  110  about the center axis C by engaging a tip portion of the minus driver with the groove  115  of the flange-like portion  114  of the eccentric bush  110 , the eccentric bush  110  is set to an initial position (position shown by the point P 0  in FIG. 4) shown by the imaginary line in FIG. 2. Next, under an action of the hammer spring  96 , the hammer  90  is turned about the eccentric bush  110 , i.e., about the center axis Q of the outer peripheral face  112  of the eccentric bush  110 , and the second-counting hand reset arm portion  94  is collided against the second heart  23 . A direction of the second heart  23 , i.e., rotation direction of the second-counting wheel  20  about the center axis C 1 , is adjusted such that the tip face  94   a  of the second-counting hand reset arm portion  94  collides against both of the two symmetrical most adjacent positions  23   a ,  23   a  of the second heart  23 . Next, under this state, the minute-counting wheel  30  is aligned in position as far as possible with respect to the tip face  93   a  of the minute-counting hand reset arm portion  93  of the hammer  90 .  
     [0055] On this occasion, if a movable range in which the minute heart  33  of the minute-counting wheel  30  is regulated by the tip face  93   a  of the minute-counting hand reset arm portion  93  is in a range of less than plus/minus 0.5 minutes, it follows that as to its position the hammer  90  is properly positioned for the present also with respect to the minute heart  33 . Additionally, if desired, the size of the gap G between the tip face  93   a  and the minute heart  33  may be judged by a visual observation and the like.  
     [0056] On the other hand, in case where a movable range of the minute heart  33  regulated by the tip face  93   a  of the minute-counting hand reset arm portion  93  exceeds plus/minus 0.5 minutes, since a clearance or the gap G between the tip face  93   a  of the minute-counting hand reset arm portion  93  and the most adjacent portions  33   a ,  33   a  of the minute heart  33  is too large (this size may be judged by the visual observation), this gap is made small by turning the eccentric bush  110  in the R1 direction with respect to the support pin  99 . Incidentally, since it follows that the rotation of the eccentric bush  110  somewhat changes a direction and a position of the tip face  94   a  of the second-counting hand reset arm portion  94  of the hammer  90 , the positions of the hammer  90  and the second heart  23  are adjusted such that the tip face  94   a  of the second-counting hand reset arm portion  94  collides against both of the two symmetrical most adjacent positions  23   a ,  23   a  of the second heart  23  at every time the eccentric bush  110  is rotated by a desired angle. In any case, by this gap reducing or decreasing operation, if the movable range of the minute heart  33  regulated by the tip face  93   a  of the minute-counting hand reset arm portion  93  becomes less than plus/minus 0.5 minutes, it follows that the gap G is suppressed within a proper range. Incidentally, under this state, if still the movable range of the minute heart  33  is comparatively wide and a suitable reduction of the gap is additionally possible, the movable range of the minute heart  33  maybe made smaller by additionally turning the eccentric bush  110  in the R1 direction.  
     [0057] In this manner, the second-counting wheel  20  including the second heart  23  (but, in this stage, the second-counting hand is not included) and the hammer  90  are positioned in predetermined positions, and the minute-counting wheel  30  including the minute heart  33  is positioned in a position within a predetermined range. Incidentally, since the minute-counting jumper  35  engages with the minute-counting gear wheel  32 , if the minute heart  33 , i.e., the minute-counting wheel  30 , is positioned with an accuracy of plus/minus 0.5 minutes for instance, a deviation less than it can be forcibly set by the minute-counting jumper  35 .  
     [0058] If such a positioning is completed, the securing screw  98  is driven, and the eccentric bush  110  is fixed to the support pin  98 . Additionally, finally, the second-counting, hand  18  is attached to the second-counting arbor  21  so as to take a proper zero position on the dial  10 , and a positioning or adjustment in the reset position, i.e., a control of the gap G, is completed.  
     [0059] On the occasion of this position adjustment, since it suffices if practically the eccentric bush  110  is merely rotated about the axis C practically within a range of less than plus/minus 90 degrees, its position adjustment can be performed easily and surely. Further, for the rotation of the eccentric bush  110 , since it suffices if it is turned by causing one engaging with the eccentric bush  110  (in this example, the minus driver engaging with the groove  114 , or the like) to engage with the bush  110 , the adjustment or control of the gap G can be easily performed in comparison with a conventional driving of the non-columnar pin or a forced rotation.  
     [0060] Further, in this case, since it suffices if the eccentric bush  110  is merely interposed in the rotation center of the hammer  90 , it is unnecessary to provide in the hammer a hole for driving the pin and an expanding slot to be split in different extent in compliance with a direction of the pin, and so on like a case of driving the non-columnar pin, so that not only an excessively large space is unnecessary but also a structure of the hammer can be simplified, and also an accuracy of its dimension/shape can be enhanced.  
     [0061] A chronograph motion itself of the chronograph mechanism  7  is similar to a conventional chronograph mechanism.  
     [0062] That is, under a usual hand movement state shown in FIG. 1, if the start/stop button  4  in FIG. 5 is pressed in the A1 direction, the operating lever  50  is pressed in the A1 direction, and the column wheel (pillar wheel)  40  is rotated by for one pitch of the ratchet teeth  41  by the pawl  51 . On this occasion, the setting portion  87   a  of the hammer click.  85  is separated from the concave portion between the adjacent drive teeth (pillars)  42 ,  42  and pushed up to the outer peripheral face of the drive teeth  42  to rotate in the R82 direction, and the hammer regulating protrusion portion  87   b  engages with the shoulder portion  97   a  of the hammer 90 to rotate the hammer  90  in an RQ2 direction and completely release interferences with respect to the minute and second hearts  33 ,  23  of the arm portions  94 ,  93  of the hammer  90 , and engages with the engaging portion  97  of the hammer  90 . Further, with the rotation of the column wheel  40 , the setting portion  62  of the stop lever  60  is pushed up to the outer peripheral face of the drive teeth  42  from the concave portion between the adjacent drive teeth  42 ,  42  to rotate the stop lever  60  in the R42 direction, and by this the chronograph coupling lever  70  is rotated in an R61 direction through the chronograph coupling lever spring  80 , and the second counter intermediate wheel  24  meshes with the second-counting gear wheel  22 . As a result, a rotation of the second-counting wheel  20  is started through the second counter intermediate wheel  24 , and a chronograph motion is started (FIG. 6).  
     [0063] On the other hand, if the start/stop button  4  (FIG. 5) is pressed again in the A1 direction, the column wheel  40  is rotated again by for one pitch of the ratchet teeth  41  through the operating lever  50 . As a result, the setting portion  62  of the stop lever  60  fits again into the concave portion between the adjacent drive teeth  42 ,  42  and is rotated in the R41 direction, and by this the chronograph coupling lever  70  is rotated in an R62 direction through the chronograph coupling lever spring  80 , so that the meshing of the second counter intermediate wheel  24  with respect to the second-counting gearwheel  22  is released. Further, by the R41 direction rotation of the stop lever  60 , the spring portion  68  of the stop lever  60  butts against the circumferential face of the second-counting gear wheel  22 , thereby maintaining the second-counting wheel  20  to a stop position. By this, the chronograph mechanism  7  adopts a stop state (FIG. 7).  
     [0064] In order to return the chronograph mechanism  7  to the usual hand movement state by resetting it, the reset button  5  (FIG. 5) is pressed in the B1 direction, thereby pressing down the hammer operating lever  84  in FIG. 7. By this, the hammer click  85  is rotated in an R81 direction through the engaging structures  84   b ,  85   a , the hammer regulating protrusion portion  87   b  of the hammer click  85  presses the hammer  90  in an RQ1 direction to separate from the shoulder portion  97   a  of the hammer  90 , and the hammer regulating protrusion portion  87   b  of the hammer click  85  fits into the concave portion between the adjacent drive teeth  42 ,  42  of the column wheel  40 . If the hammer click  85  separates from the hammer  90 , the hammer  90  is rotated in the RQ2 direction under an action of the hammer spring  96  and, by the fact that tip end face  94   a  of the second-counting hand reset arm portion  94  collides against the second heart  23  to thereby position the second heart  23  to an initial position, the second-counting wheel  20  is returned to an initial position, thereby resetting the second-counting hand  18 . With the rotation, in the RQ2 direction, of the hammer  90  position-adjusted by the eccentric bush  110 , at the same time the tip face  93   a  of the minute-counting hand reset arm portion  93  collides against the minute heart  33  to thereby return the minute heart  33  to a vicinity of the initial position and, under an action of the minute-counting jumper  35 , the minute-counting wheel  30  is accurately returned to the initial position, so that the minute-counting hand  17  is reset.  
     [0065] Incidentally, in the above, it has not been explained about the hour-counting hand, but the hour-counting hand is chronograph-operated by a mechanism similar to such a conventional mechanism as described in JP-A-11-183653 Gazette.