Abstract:
A power reserve mechanism has a ratchet wheel having a winding stem, a first winding stem train wheel connected to the winding stem of the ratchet wheel and having a first power reserve wheel, and a barrel member having a winding stem. A spring member is mounted in the barrel member. A second winding stem train wheel independent from the first winding stem train wheel is connected to the winding stem of the barrel member and has a second power reserve wheel. A first indicator is disposed on the first power reserve wheel. A second indicator is disposed on the second power reserve wheel. An amount of spring power stored by the spring member is indicated utilizing a relative variation in movement between the first and second indicators.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a power reserve mechanism and indicator unit for same and, more particularly, to a power reserve mechanism and indicator unit for same which indicates a power storage amount using two indicator hands and the like. 
     2. Background of the Invention 
     FIG. 6 is a sectional view showing a train wheel structure of a power reserve structure. FIG. 7 is a top view showing the train wheel of the power reserve structure shown in FIG.  6 . The power reserve mechanism  500  train wheel is structured by a barrel complete  501  accommodating a spiral spring as a power source, a ratchet wheel  502  arranged on a dial side of the barrel complete  501 , a intermediate planetary wheel gear  503  in mesh with the barrel complete  501 , a planetary wheel  504  rotatably arranged in an eccentric part of the intermediate planetary wheel gear  503 , a planetary wheel gear  505  and planetary pinion  506  fixed to the planetary wheel  504  in a form sandwiching the intermediate planetary wheel gear  503 , a sun wheel  507  in mesh with the planetary pinion  506  of the planetary wheel  504 , on the other hand a second sun wheel  508  in mesh with the planetary wheel gear  505  of the planetary wheel  504 , a intermediate indicator wheel  510  in mesh with the sun pinion  509  of the sun wheel  507 , a indicator wheel  512  in mesh with the intermediate indicator pinion  511  of the intermediate indicator wheel  510 , and a intermediate planetary wheel  514  in mesh with the ratchet wheel  502  and the second sun wheel gear  513  of the second sun wheel  508 . 
     A reference numeral  515  is an indication degree determining pin. The intermediate indicator wheel  510  is structured to slip at a contact point when a predetermined difference of torque is caused between the intermediate indicator wheel gear  5101  and the intermediate indicator wheel pinion  511 . The indicator wheel  512  is provided with a fan-shaped cutout  516  to view the indication degree determining pin  515 . The indication degree determining pin  515  is secured to a second wheel train bridge  601  to regulate an angle of rotation of the indicator wheel  512 . 
     Next, the operation of the power reserve mechanism will be explained. When spring power to the spiral spring, the ratchet wheel  502  is first rotated through a crown, winding stem and crown wheel from an outside. Because the intermediate planetary wheel gear  503  is regulated in rotation by the barrel complete  501 , the same intermediate planetary wheel gear  503  is a substantially fixing gear. The rotation of ratchet wheel  502  is transmitted through the intermediate planetary wheel  514 , second sun gear  508 , planetary gear  504 , sun gear  507 , intermediate indicator wheel  510  and indicator wheel  512 , in this order. This causes the indicator wheel  512  to rotate leftward (reverse to a rotation direction in usual hand movement). The rotation of indicator wheel  512  causes the indicator hand  517  mounted on the indicator wheel  512  to rotate in a spiral spring power storing direction. 
     If the spiral spring achieves a fully wound state, the fan-shaped cutout  516  of the indicator wheel  512  and the indication degree determining pin  515  are brought into engagement to thereby regulate rotation of the indicator wheel  512 . In this case, slip occurs at a contact plane between the intermediate indicator wheel gear  5101  and the intermediate indicator wheel pinion  510 . Due to this, even if the crown is excessively wound, the indicator hand  517  is unchanged in position without imposing a load onto the train wheel. 
     Next, during usual movement of the hands, the power on the barrel complete  501  is transmitted from the barrel complete gear  5011  to the intermediate planetary wheel gear  503 . On the other hand, the second sun wheel  508  coaxial to the intermediate planetary wheel gear  503  is in mesh with the ratchet wheel  502  through the intermediate planetary wheel  514 . Because this ratchet wheel  502  is out of rotation during usual hand movement, the second sun wheel  508  is a fixing gear. Consequently, when the intermediate planetary gear wheel  503  rotates, the planetary wheel  504  of the intermediate planetary wheel gear  503  makes movement of rotation and revolution along the second sun wheel  508 . Because the sun wheel gear  5072  and the planetary pinion  506  are secured on a sun stem  5071  and in mesh with each other, the rotation of planetary wheel  504  is transmitted to the indicator wheel  512  through the sun wheel gear  5072 , sun stem  5071 , sun pinion  509  and intermediate indicator wheel  510 . The rightward rotation of indicator wheel  512  also rotates rightward the indicator hand  517  mounted on the indicator wheel  512 . It will be understood that as this indicator hand  517  rotates rightward the power storage amount on the spiral spring decreases. 
     However, the prior art power reserve mechanism  500  using the planetary wheel gear mechanism comprising the planetary wheel  504 , etc. have involved the following problems: 
     (1) cost increase because of increased number of movement parts, 
     (2) difficult and troublesome assembling because of increased number of movement assembling steps; 
     (3) reduced freedom in method of indicating a spiral spring power storage amount, 
     (4) much sectional space required. 
     Therefore, the present invention has been made in view of the above, and it is an object to provide a power reserve mechanism and indicator unit thereof which is 
     (1) capable of reducing the number of parts, 
     (2) easy to assemble, 
     (3) obtain a freedom of a method of indicating a spiral spring power storage amount, 
     (4) capable of reducing sectional space. 
     SUMMARY OF THE INVENTION 
     In order to achieve the above object, a power reserve mechanism comprises: a first power reserve wheel for obtaining rotation of a ratchet wheel through a train wheel; a first indicator member attached on the first power reserve wheel; a second power reserve wheel for obtaining rotation of a barrel complete through a train wheel; a second indicator member attached on the second power reserve wheel to change relative to the first indicator member; wherein a spiral spring power storage amount is indicated by a difference between the first indicator member and the second indicator member. 
     That is, a spiral spring power storage amount is indicated by a relative change of the first indicator member and the second indicator member. Where a remaining amount is indicated by one indicator member (indicator hand) as in the conventional, there is a need to rotate the one indicator member in respective directions thereby requiring a planetary gear mechanism. However, indication by a mere relative change requires rotation only in one direction. Accordingly, a planetary gear mechanism is not necessary. Also, the structure is simple because only relative change is made by the two indicator members. As a result, the number of parts can be reduced and assembling is facilitated. Also, indicator freedom increases. Furthermore, because it is possible to structure by simple two train wheels, space efficiency is good due to the planar structure. 
     An indicator unit of the power reserve mechanism is disposed coaxially relative to the first power reserve wheel connected to the first indicator member and the second power reserve wheel connected to the second indicator member, so that a spiral spring power storage amount is indicated by a difference between the first indicator member and the second indicator member. By this construction, it is possible to determine a spiral spring power storage amount from the relative position relationship between both indicator members. Furthermore, in order to transmit rotation to the indicator members, separate train wheels may be connected respectively from the ratchet wheel and the barrel complete. 
     In another a power reserve mechanism comprises: a first power reserve wheel for obtaining rotation of a ratchet wheel through a train wheel; a first indicator hand attached on the first power reserve wheel; a second power reserve wheel for obtaining rotation of a barrel complete through a train wheel; a second indicator hand attached on the second power reserve wheel to change relative to the first indicator hand; wherein a spiral spring power storage amount is indicated by a difference between the first indicator hand and the second indicator hand. 
     In this manner, each indicator member may, for example, be an indicator hand. Where indicating by indicator hands, a remaining amount can be determined by a spacing between the first indicator hand and the second indicator hand. 
     In another embodiment, a power reserve mechanism comprises: a first power reserve wheel for obtaining rotation of a ratchet wheel through a train wheel; a fun-shaped scale plate attached on the first power reserve wheel; a second power reserve wheel for obtaining rotation of a barrel complete through a train wheel; an indicator hand attached on the second power reserve wheel to change relative to the scale plate; wherein a spiral spring power storage amount is indicated by a division point of the scale plate pointed by the indicator hand. 
     In this manner, where the indicator member on a ratchet wheel side uses a fan-shaped scale plate and the indicator member on a barrel complete side uses an indicator hand, a remaining amount can be determined by a position of the indicator hand on the scale plate. 
     In another embodiment, a power reserve mechanism comprises: a first power reserve wheel for obtaining rotation of a ratchet wheel through a train wheel; an indicator hand attached on the first power reserve wheel; a second power reserve wheel for obtaining rotation of a barrel complete through a train wheel; a scale plate attached on the second power reserve wheel to change relative to the indicator hand; wherein a spiral spring power storage amount is indicated by a division point of the scale plate pointed by the indicator hand. 
     In this manner, where the indicator member on the ratchet wheel side uses an indicator hand and the indicator member on the barrel complete side uses a scale plate, a remaining amount can be determined by a position of the indicator hand on the scale plate. 
     In another embodiment, a power reserve mechanism comprises: an intermediate power reserve train wheel for transmitting rotation of a ratchet wheel; a first power reserve wheel for obtaining rotation from the first intermediate power reserve train wheel; a first indicator member attached on the first power reserve wheel; an intermediate second power reserve train wheel for transmitting rotation of a barrel complete; a second power reserve wheel for obtaining rotation from the intermediate second power reserve train wheel; a second indicator member attached on the second power reserve wheel to change relative to the first indicator member; wherein a spiral spring power storage amount is indicated by a difference between the first indicator member and second indicator member. 
     By this structure, a remaining amount can be indicated by a relative position of the first indicator member and the second indicator member. Accordingly, a planetary gear structure is not necessarily provided in order to obtain rotation in respective directions. Also, a power reserve mechanism can be structured by a simple train wheel. As a result, the number of parts can be educed and assembling is facilitated. Also, indicator freedom increases. Furthermore space efficiency is good because of the planar structure. 
     Also, an indicator unit for a power reserve mechanism according to claim  7  is structured coaxially by a first power reserve wheel attached with a first indicator member and a second power reserve wheel attached with a second indicator member, and characterized in that a spiral spring power storage amount is indicated by a difference between the first indicator member of the first power reserve wheel and second indicator member of the second power reserve wheel. 
     If the first indicator member and the second indicator member are coaxially structured, a spiral spring power storage amount can be determined from a relative position relationship between the both members. Incidentally, in order to transmit rotation to the both members, separate train wheels may be connected respectively from the ratchet wheel and the barrel complete. 
     Also, an indicator unit for a power reserve mechanism according to claim  8  is structured, in the above power reserve mechanism indicator unit, such that the first indicator member is an indicator hand or scale plate, and the second indicator member being a scale plate or indicator hand. 
     In this manner, the indicator members include an indicator hand and a scale plate. The indicator hands may be respective scale plates or a combination of an indicator hand and a scale plate. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a top view showing a power reserve mechanism of this invention. 
     FIG. 2 is a top view showing first power reserve train wheel of the power reserve mechanism shown in FIG.  1 . 
     FIG. 3 is a top view showing a second power reserve train wheel of the power reserve mechanism shown in FIG.  1 . 
     FIG. 4 is a top view showing indicator hands of the power reserve mechanism. 
     FIGS.  5 ( a )- 5 ( c ) are explanatory views showing an indication example of a spiral spring remaining amount. 
     FIG. 6 is a top view showing a conventional power reserve mechanism. 
     FIG. 7 is a top view showing a power reserve mechanism shown in FIG.  6 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Hereunder, the present invention will be explained in detail with reference to the drawings. Incidentally, the invention is not limited to by this embodiment. 
     FIG. 1 is a top view showing a power reserve mechanism of the invention. FIG. 2 is a sectional view showing a first power reserve train wheel of the power reserve mechanism shown in FIG.  1 . FIG. 3 is a sectional view showing a second power reserve train wheel of the power reserve mechanism shown in FIG.  1 . In FIG. 1 a main plate is omitted. A power reserve mechanism  100  of the invention is provided separately with a first power reserve train wheel  150  and a second power reserve train wheel  160 . Each train wheel has a power reserve wheel provided with an indicator hand to indicate an amount of spiral spring storage power. 
     Referring to FIG.  1  and FIG. 2, the first power reserve train wheel is first explained. The first power reserve train wheel  150  is structured by a ratchet wheel  2  attached to a dial plate side of a barrel complete  1 , an intermediate first power reserve wheel  3  in mesh with this ratchet wheel  2 , an intermediate second power reserve wheel  4  in mesh with an intermediate first power reserve wheel pinion  31  of the intermediate first power reserve wheel  3 , and a first power reserve wheel  5  in mesh with an intermediate second power reserve wheel pinion  41  of the intermediate second power reserve wheel  4 . This first power reserve wheel  5  which is structured to slip when a predetermined torque difference occurs in a contact plane between the gear and the pinion  41 , is mounted with a first indicator hand  51 . The ratchet wheel  2  is fixed on a shaft of the barrel complete  1  through a ratchet screw  21 . The intermediate power reserve wheel  3  is rotatably supported at its shaft between a power reserve wheel bridge  103  and a third bridge  104 . The intermediate first second power reserve wheel  4  is rotatably supported at its shaft between a main plate  101  and a barrel bridge  102 . The first power reserve wheel  5  is rotatably assembled between the main plate  101  and the power reserve wheel bridge  105 , and the main plate  101  serves as a bearing for the power reserve hour part  52 . Also, the first power reserve wheel  5  is opened with an elongate hole  53  in which a pin  83  for the power reserve wheel, hereinafter described, is to be inserted. 
     Next, the second power reserve train wheel  160  is explained with reference to FIG.  1  and FIG.  3 . The second power reserve train wheel  160  is structured by a barrel member (herein after “barrel complete”)  1  accommodating a spiral spring as a power source, an intermediate third power reserve wheel  6  in mesh with a barrel complete gear  11  provided around the barrel complete  1 , an intermediate fourth power reserve wheel  7  in mesh with an intermediate third power reserve wheel pinion  61  of the intermediate third power reserve wheel  6 , and a second power reserve wheel  8  in mesh with an intermediate fourth power reserve wheel pinion  71  of the intermediate fourth power reserve wheel  7 . This second power reserve wheel  8  is mounted with a second indicator hand  81 . The barrel complete  1  is rotatably supported at its shaft between the main plate  101  and the barrel bridge  102 . The intermediate third power reserve wheel  6  is rotatably supported at its shaft between the main plate  101  and the barrel bridge  102 . The intermediate fourth power reserve wheel  7  are rotatably supported at its shaft between the second wheel bridge  106  and the barrel bridge  102 . The second power reserve wheel  8  is rotatably assembled between the main plate  101  and the power reserve wheel bridge  105 . Also, this second power reserve wheel  8  has at a shaft part  82  an hour part  52  of the first power reserve wheel  5  and penetrates through the hour part  52 . Also, the second power reserve wheel  8  is provided with a projecting power reserve wheel pin  83 . The power reserve wheel pin  83  is inserted through an elongate hole  53  of the first power reserve wheel  5  and restricted in movement by a shape of the elongate hole  53 . 
     A reference numeral  106  is a crown. The crown  106  is attached to one end of a hand setting stem  107 . This hand setting stem  107  has at the other end a winding pinion  108 . The winding pinion  108  is in mesh with a crown wheel  109  to alter a rotation axis direction by 90 degrees. The crown wheel  109  is in mesh with a ratchet wheel  2  to convey rotation from the crown  106  to the ratchet wheel  2 . Also, the ratchet wheel  2  is attached with a click  22  to regulate rotation of the ratchet wheel  2  to one direction. Incidentally, the first power reserve train wheel  150  and the second power reserve train wheel  160  both do not use a planetary wheel mechanism. 
     FIG. 4 is a top view showing an indicator hand for the power reserve mechanism  100 . An example is shown with a dial  171  for a three hand watch. The dial  171  after assembling is positioned under the main plate. A reference numeral  172  is a remaining amount indicator part to indicate an amount of spiral spring storage power. The remaining amount indicator part  172  is arranged at an eccentric position from a center of the dial  171 . A first indicator hand  51  and a second indicator hand  81  respectively use small hands. Particularly, the second indicator hand  81  is formed with a teaching part  84  to represent a direction for determining a remaining amount. Incidentally, although a scale plate may be used in place of the indicator hands, a concrete example thereof will be described hereafter. 
     Next, the operation of the power reserve mechanism  100  is explained. 
     [In Spiral Spring Power Storage] 
     The crown  106  if rotated transmits its rotation to the crown wheel  109  through the winding stem  107  and winding pinion  108 . Because the crown wheel  109  and the ratchet wheel  2  are meshed with, the rotation of the crown wheel  109  rotates the ratchet wheel  2 . The ratchet wheel  2  is regulated in direction of rotation by the click  22 . Due to this, the ratchet wheel  2  will not be reversely rotated by a force of the spiral spring. The ratchet wheel  2  if rotated transmits its rotation to the intermediate first power reserve wheel  3 . Since the intermediate first power reserve wheel pinion  31  meshes with the intermediate second power reserve wheel  4 , the rotation of the intermediate first power reserve wheel  3  is transmitted to the intermediate second power reserve wheel  4 . Because the intermediate second power reserve wheel pinion  41  meshes with the first power reserve wheel  5 , the rotation of the intermediate second power reserve wheel  4  is transmitted to the first power reserve wheel  5 . The rotation of the ratchet wheel  2  is reduced as transmitted through the intermediate first power reserve wheel  3 , intermediate second power reserve wheel  4  and first power reserve wheel  5 . The rotation of the first power reserve wheel  5  causes the first indicator hand  51  mounted on its hour part  52  to rotate over the remaining amount indicator part  172  in the dial  171 . 
     On the other hand, the second indicator hand  81  is almost in an non-rotation state. This is because the barrel complete  1  is very slow in rotation and accordingly the train wheel formed by the intermediate third power reserve wheel  6 , intermediate fourth power reserve wheel  7  and second power reserve wheel  8  is regulated in rotation thus placing the second power reserve wheel  8  substantially in a fixed state. Due to this, as shown in FIG. 4 the first indicator hand  51  and the second indicator hand  81  have an increased spacing due to rotation of the first indicator hand  51 . The first indicator hand  51  and the second indicator hand  81  are restricted in their maximum spacing by engagement of the elongate hole  53  of the first power reserve wheel  5  with the power reserve wheel pin  83  of the second power reserve wheel  8 . 
     [In Normal Hand Movement] 
     In normal hand movement the ratchet wheel  2  will not rotate. This is because the click  22  regulates against reverse rotation. Accordingly, the train wheel formed by the intermediate first power reserve wheel  3 , intermediate second power reserve wheel  4  and first power reserve wheel  5  is regulated in rotation and the first power reserve wheel  5  is substantially a fixed wheel. Therefore, the first indicator hand  51  put on the first power reserve wheel  5  remains fixed at the rotated position. If the barrel complete  1  now rotates, its rotation is transmitted to the intermediate third power reserve wheel  6 . Because the intermediate third power reserve wheel pinion  61  is in mesh with the intermediate fourth power reserve wheel  7 , the rotation of the intermediate third power reserve wheel  6  is transmitted to the intermediate fourth power reserve wheel  7 . Also, because the intermediate fourth power reserve wheel pinion  71  meshes with the second power reserve wheel  8 , the rotation of the intermediate fourth power reserve wheel  7  is transmitted to the second power reserve wheel  8 . The rotation of the barrel train  1  is reduced through the intermediate third power reserve wheel  6 , intermediate fourth power reserve wheel  7  and second power reserve wheel  8 . If the second power reserve wheel  8  rotates, the second indicator hand  81  put on its shaft part  82  rotates over the remaining amount indicator part  172  of the dial  171 . The rotational direction of the second indicator hand  81  becomes same as the rotational direction of the first indicator hand  51 . Consequently, the rotation of the second indicator hand  81  reduces the spacing to the first indicator hand  51 . At a time point of agreement between the second indicator hand  81  and the first indicator hand  51 , it can be found that there is no remaining amount on the spiral spring. 
     As described above, according to this power reserve mechanism  100 , the first indicator hand  51  and the second indicator hand  81  are rotated in the same direction to have a spacing between the both thereby indicating a remaining amount on the spiral spring. Thus, there is no need to use a planetary mechanism for each train wheel. Due to this, it is possible to reduce the number of parts for the power reserve mechanism  100 . Also, the structure is simple and hence easy to assemble. Furthermore, sectional spacing can be reduced. 
     FIG. 5 shows an explanatory view showing an example of indicating a power storage amount on the spiral spring. As shown in (a) of the figure, a fan-shaped scale plate  201  may be attached to the first power reserve wheel  5  and an indicator hand  202  be on the second power reserve wheel  8 . This makes it possible to indicate a spiral spring power storage amount by a position of the indicator hand  202  over the scale plate  201 . Also, fan-shaped scale plates may be mounted on the first power reserve wheel  5  and the second power reserve wheel  8 . This also can indicate a spiral power storage amount due to a relative change of position between the scale plates. 
     Also, colors may be provided to the scale plate to give indication with change of color. As shown in (b) of the figure, for example scale plates  203 ,  204  are given different colors that are mounted on the first power reserve wheel  5  and second reserve power wheel  8  so that one scale plate  203  covers over the other scale plate  204 . In this case, when one color becomes invisible, it can be judged that there is no amount of spiral spring storage power. Incidentally, regardless of the above example shown in the figure, the member is not limited to the indicator hand or scale plate provided that relative change is to be found. For example, as shown in (c) of the figure, circular indicator plates  205 ,  206  may be attached to the first power reserve wheel  5  and second power reserve wheel  8  to add design elements. 
     As explained above, according to a power reserve mechanism of the invention, respective train wheels for rotating the first indicator member and the second indicator member are provided independently and in parallel so that a spiral spring power storage amount is indicated by a relative change of the first indicator member and the second indicator member. Accordingly, the power reserve mechanism is simple in structure. Due to this, the number of parts can be reduced and assembling is facilitated. Also, indication freedom increases. Furthermore, space efficiency is good due to the planar structure. 
     Also, because the first indicator member and the second indicator member are coaxially structured, a spiral spring power storage amount can be determined from the relative position relationship of both indicator members rotating about the same axis. This indicator unit is adapted for the above power reserve mechanism. 
     According to a next power reserve mechanism, because the indicator members use indicator hands, a remaining amount can be determined by a spacing between the first indicator hand and the second indicator hand. 
     According to a next power reserve mechanism because the indicator member on a ratchet wheel side uses a fan-shaped scale plate and the indicator member on a barrel complete side uses an indicator hand, a remaining amount can be determined by a position of the indicator hand on the scale plate. 
     According to a next power reserve mechanism, because the indicator member on the ratchet wheel side uses an indicator hand and the indicator member on the barrel complete side uses a scale plate, a remaining amount can be determined by a position of the indicator hand on the scale plate. 
     According to a next power reserve mechanism, independently provided are an intermediate first power reserve train wheel for transmitting rotation of a ratchet wheel and a first power reserve wheel and an intermediate second power reserve train wheel for transmitting rotation of a barrel complete and a second power reserve wheel. The first power reserve wheel and the second power reserve wheel of each train wheel are respectively provided with a first indicator member and a second indicator member so that a spiral spring power storage amount is indicated by a relative change between the first indicator member and second indicator member. Due to this, the power reserve mechanism is made simple in structure. Due to this, the number of parts can be educed and assembling is facilitated. Also, indication freedom increases. Furthermore space efficiency is good because of the planar structure. 
     According to a next power reserve mechanism, because a first indicator member and a second indicator member are coaxially structured. Accordingly it is possible to determine a spiral spring power storage amount from a relative position relationship between the both indicator member rotating about a same axis. This indicator unit is adapted for the above power reserve mechanism. 
     According to a next power reserve mechanism (claim  7 ), because the first indicator member is an indicator hand or scale plate, and the second indicator member being a scale plate or indicator hand. Accordingly, it is possible to indicate a spiral spring power storage amount in an intelligibly manner.