JP6091298B2 - Escapement, movement, and watch - Google Patents

Description

  The present invention relates to an escapement, a movement, and a timepiece having the same.

  Conventionally, an escapement having a stone (entry claw, exit claw) that controls the rotation of the escape wheel and receives the rotational force of the escape wheel has been most widely used. The Swiss Lever (Club Tooth) escapement is known. In such a conventional Swiss lever escapement, the claw is configured to receive the rotational force from the escape wheel as follows.

  Such a conventional escapement will be described with reference to FIG. First, during the period in which the balance stone 3102 of the balance is vibrating without coming into contact with the ankle 3105, the sao 3118 of the ankle 3105 is stopped by hitting 3103a, and the escape gear 3122 is in the locking corner of the escape tooth. 3124 is engaged with the stop surface 3111 of the ankle claw 3110 of the ankle and stopped. This state is called a stop period. The escape gear 3122 is biased clockwise by power from a barrel not shown. In addition, when a normal line is drawn at the contact point between the locking corner 3124 of the escape tooth and the stop surface 3111 of the nail, this is the direction of the force transmitted from the escape tooth 3121 to the entry nail 3110 during the stop period. When a straight line connecting the swing axis C1 of the ankle and the rotation axis of the escape gear 3122 is a center line V, the intersection T between the normal 3115 and the center line V is more than the swing axis C1 of the ankle. It is in the place away in the direction of the side where rotation axis C2 of escape wheel 3122 is arranged. This means that the escape gear 3122 applies a counterclockwise rotational force to the ankle 3105 even during the stop period. By the action of this force, the ankle sao 3118 is pressed against the 3103, and even if an impact is applied from the outside during the stop period, the ankle 3105 is prevented from easily coming away from the 3103a, and the ankle 3105 is kept in balance. The free vibration of the balance with hairspring 3101 and gangue 3102 is prevented from being disturbed. The angle of the stop surface 3111 of the nail provided with respect to the plane orthogonal to the line connecting the rocking axis C1 of the ankle and the locking corner 3124 of the escape tooth is called the pulling angle.

  As shown in FIG. 11, when the stoppage period of the claw is started, the balance is separated from the pallet 3102 of the swing seat 3101 from the ankle 3105, rotates clockwise by inertia, and the rotational energy is attached to the balance. It is stored in a hairspring (not shown). When all the rotational energy is stored in the hairspring, the balance stops rotating clockwise and stops for a moment, and immediately after that, the balance starts to rotate counterclockwise by the energy stored in the hairspring. The pendulum 3102 fixed to the balance of the balance with hairspring 3101 approaches the box 3106 of the ankle 3105 and eventually collides with the surface 3108 on the protruding claw side of the inner peripheral surface of the box. The ankle 3105 is rotated in the clockwise direction by the force on the protruding claw side 3108 of the inner peripheral surface of the box receiving a force from the rock stone 3102. At this time, since the nail 3110 also rotates with the rotation of the ankle 3105, when the nail 3110 rotates by a certain angle, the locking corner 3124 of the escape tooth reaches the locking corner 3112 of the nail. Such a period until the rocking corner 3124 reaches the rocking corner 3112 of the claw stone after the pendulum 3102 collides with the box 3106 is referred to as stop release. When the stop release is completed, the locking corner 3124 of the escape tooth collides with the impact surface 3113 of the nail. After the collision, the locking corner 3124 of the hooked tooth slides on the impact surface 3113 of the nail so as to impart a clockwise rotational force to the ankle 3105. The ankle 3105 to which the rotational force is given by the escape teeth 3123 gives the balance to the balance with the face 3107 on the claw side of the inner peripheral surface of the box engaging with the gangue.

  Here, paying attention to the torque ratio of the balance with respect to the escape wheel 3121 during the stop release period in the ingrown claw, the torque of the balance necessary to reverse the escape wheel increases during the stop release period. . The reason is described below. Here, the torque ratio is a ratio of torques applied to the respective rotating objects when the rotating objects (for example, gears) that are rotating with each other while engaging are stationary due to the balance of torque.

  The torque ratio of the balance with respect to the escape wheel 3121 is represented by the product of the torque ratio of the balance with respect to the ankle and the torque ratio of the ankle with respect to the escape wheel. First, when considering the torque ratio of the balance with respect to the ankle, it is as follows.

  Consider the transmission of force from the balance stone 3102 of the balance to the surface 3108 on the protruding claw side of the inner peripheral surface of the box. When viewed statically, the transmission direction of the force from the rock stone 3102 to the protruding claw side 3108 of the inner peripheral surface of the box is from the contact point of the rock stone 3102 and the surface 3108 of the inner peripheral surface of the box to the inner periphery of the box. Although the direction of the normal 3151 is drawn with respect to the surface 3108 on the protruding claw side of the surface, there is friction between the rock stone 3102 and the surface 3108 on the protruding claw side of the inner peripheral surface of the box. The transmission direction of the force from the stone 3102 to the surface 3108 on the protruding claw side of the inner circumferential surface of the box is a direction deviated from the normal 3151 by the friction angle λ1 in the direction of the rotation center C3 of the balance. Here, assuming that the intersection of the force transmission direction 3152 and the center line V is S, the torque ratio between the balance with the balance 3105 is the distance from the balance center C3 to S of the balance with the swing axis C1 to S of the ankle. Is equal to the distance ratio. By the fact that the inner peripheral surface of the box 3106 is a flat surface and the oscillating stone 3102 moves on the circumference, the intersection S moves toward the swing axis C1 of the ankle during the period of release of the stop. Go. Therefore, the torque ratio of the balance with respect to the ankle 3105 increases during the stop cancellation period.

  Next, consider the torque ratio of the ankle to the escape wheel. Consider the direction of force transmission from the locking corner 3124 of the escape tooth to the nail stop surface 3111. When viewed statically, the transmission direction of the force from the locking corner 3124 of the escape tooth to the entry nail stop surface 3111 is the method of pulling from the locking corner 3124 of the escape tooth tooth to the entry nail stop surface 3111. In the direction of the line 3115, there is friction between the locking corner 3124 of the hook teeth and the nail stop surface 3111, so the locking corner 3124 of the hook teeth during the stop release period to the nail stop surface 3111 The direction of force transmission is a direction deviated from the normal 3115 by the friction angle λ2 toward the rotation center C2 of the escape wheel 3121. Here, assuming that the intersection of the force transmission direction 3116 and the center line V is T ′, the torque ratio between the ankle 3105 and the escape wheel 3121 is the distance from C1 to T ′ and the distance from C2 to T ′. Is equal to the ratio of Since the stop surface 3111 of the entering claw is a flat surface, the intersection point T ′ moves toward the rotation axis C2 of the escape wheel during the stop cancellation period. Therefore, the torque ratio of the ankle to the escape wheel increases during the stop release period of the entering claw.

  From the above, the product of the torque ratio of the balance with respect to the escape wheel, that is, the torque ratio of the balance with respect to the ankle and the torque ratio of the ankle with respect to the escape wheel, increases during the period of release of the stop at the entering claw.

  The escape wheel 3121 is urged clockwise from an unillustrated barrel through a not-illustrated train wheel, and the torque can be considered constant during the period of release of the stop. Therefore, the torque of the balance necessary for reversing the escape wheel 3121 increases during the stop release period of the entering claw 3111.

  Accordingly, the energy lost by the starch during the stop cancellation period also increases. An increase in the energy loss of the balance with hairspring leads to a decrease in swing angle. As the balance angle of the balance is larger, the balance is less susceptible to external impacts, and the balance of the balance of the balance can be maintained with high accuracy.

By George Daniels “Watchmaking”, Sotheby Parke Bern Publications, 1982, p. 206-221.

  The present invention has been made in view of such circumstances, and its purpose is to reduce the torque ratio of the ankle to the escape wheel while the torque ratio of the balance with the ankle increases during the stop release period of the entering nail. It is providing the escapement, the movement, and the timepiece which can suppress by this, and can suppress the loss of the energy of a balance with hairspring.

The escapement according to the present invention is provided with a escape gear that can rotate around a rotation axis, an engaging claw that can be engaged with and disengaged from the escape gear, and an oscillation that swings around an oscillation shaft. In the escapement having an ankle, the engagement surface of the engagement claw with the escape gear is an intersection where a straight line passing through the rotation shaft and the swing shaft intersects with a torque transmission direction on the engagement surface. However, the main feature is that it is formed in a shape that is displaced from the rotating shaft so as to approach the swinging shaft as the escape gear rotates.
With this configuration, during the period of release of the stop at the entering claw, an increase in the torque ratio of the balance with respect to the ankle can be suppressed by a decrease in the torque ratio of the ankle with respect to the escape wheel, and a loss of energy of the balance can be suppressed.

The escapement according to the present invention is characterized in that the shape of the engagement surface is formed so that the torque transmission direction is a normal line to the engagement surface.
With this configuration, when the friction between the engagement tooth of the escape tooth and the nail is very small, an increase in the torque ratio of the balance with respect to the ankle during the period of release of the stop at the entry nail, the torque ratio of the ankle to the escape wheel It can be suppressed by reducing the energy loss of the balance with the balance.

In the escapement according to the present invention, the torque transmission direction is deviated from a normal to the engagement surface by a friction angle caused by contact between the engagement claw and the escape gear on the engagement surface. Thus, the shape of the engagement surface is formed.
With this configuration, when there is friction between the engagement surfaces of the escape teeth and the nail, the torque ratio of the balance with respect to the ankle increases during the release of the stop at the entry nail, and the torque ratio of the ankle to the escape wheel decreases. The energy loss of the balance with hairspring can be suppressed.

The escapement according to the present invention is configured so that the intersection point is located within a line segment connecting the rotation shaft and the swing shaft regardless of the rotation angle of the escape gear. A shape is formed.
With this configuration, the force transmitted to the ankle while the ankle and the escape gear are stopped works to rotate the ankle counterclockwise, so that when an impact is applied from the outside. The ankle can be easily prevented from coming back and hindering the vibration of the balance.

The movement according to the present invention is characterized by including the escapement, a balance that adjusts the oscillation cycle of the ankle, and a train wheel that transmits power to the escape gear.
With such a configuration, a highly accurate movement can be provided.

The timepiece according to the present invention is characterized in that it has a hand that rotates at a rotational speed regulated by an escapement speed adjusting mechanism including the movement, the escapement, and the balance.
With this configuration, a highly accurate timepiece can be provided.

  The escapement of the present invention can suppress the increase in the torque ratio of the balance with respect to the ankle by the decrease in the torque ratio of the ankle with respect to the escape wheel during the release period of the stop, thereby suppressing the loss of energy of the balance. There is an advantage that a desired swing angle can be secured.

It is a figure at the time of the stop cancellation | release start of the escapement in 1st Embodiment of this invention. It is a figure at the time of completion | finish of stop cancellation | release of the escapement in 1st Embodiment of this invention. It is a figure at the time of the stop release start of the escapement in 2nd Embodiment of this invention. It is a figure at the time of completion | finish of stop cancellation | release of the escapement in 2nd Embodiment of this invention. (A) It is a figure of the movement provided with the escapement regarding 1st Embodiment of this invention. (B) It is a figure of a timepiece provided with the movement concerning a 1st embodiment of the present invention. It is a torque ratio diagram of a balance with an ankle in the prior art. It is a torque ratio diagram of an ankle to a escape wheel in the prior art. It is a torque ratio diagram of a balance with a escape wheel in the prior art. It is a torque ratio diagram of an ankle with respect to the escape wheel of the present invention. It is a torque ratio diagram of the balance with respect to the escape wheel of the present invention. It is a figure in the stop period of the escapement in a prior art.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. 1, 2, 5, and 6 to 10. FIG. Initially, the structure of the escapement of this embodiment is demonstrated based on FIG. 1, FIG. FIG. 1 is a diagram at the start of stop release of the escapement of the present embodiment, FIG. 5A is a configuration diagram of a movement including the escapement of the present embodiment, and FIG. It is a figure of a timepiece provided with such a movement.

(Explanation of watch)
As shown in FIGS. 5A and 5B, the mechanical timepiece 1 of this embodiment is, for example, a wristwatch, and includes a movement (timepiece movement) 10 and a casing 2 that houses the movement 10. , Is configured.

(Description of the movement)
This movement 10 has a base plate 11 constituting a substrate. A dial (not shown) is arranged on the back side of the main plate 11. A train wheel incorporated on the front side of the movement 10 is referred to as a front train wheel, and a train wheel incorporated on the back side of the movement 10 is referred to as a back train wheel.

  A winding stem guide hole 11a is formed in the base plate 11, and a winding stem 12 is rotatably incorporated therein. The winding stem 12 is positioned in the axial direction by a switching device having a setting lever 13, a yoke 14, a yoke spring 15 and a back presser 16. In addition, a chichi wheel 17 is rotatably provided on the guide shaft portion of the winding stem 12.

  Under such a configuration, the winding stem 12 is rotated in a state where the winding stem 12 is in the first winding stem position (0th stage) closest to the inside of the movement 10 along the rotation axis direction. Then, the hour wheel 17 rotates through the rotation of the spell wheel (not shown). And when this chi-wheel 17 rotates, the round hole wheel 20 which meshes with this rotates. And when this round hole wheel 20 rotates, the square wheel 21 which meshes with this rotates. Further, when the square hole wheel 21 rotates, the mainspring (power source) (not shown) housed in the barrel complete 22 is wound up.

  The front wheel train of the movement 10 includes a second wheel 25, a third wheel 26 and a fourth wheel 27 in addition to the barrel wheel 22, and functions to transmit the rotational force of the barrel wheel 22. Further, an escapement 30 and a speed control mechanism 31 for controlling the rotation of the front wheel train are disposed on the front side of the movement 10. The speed regulating mechanism 31 is a mechanism for regulating the escapement, and includes a balance 40. The center wheel 25 is a gear that meshes with the barrel complete 22. The third wheel 26 is a gear that meshes with the second wheel 25. The fourth wheel 27 is a gear that meshes with the third wheel 26.

(Explanation of escapement)
As shown in FIG. 1, the escapement 30 according to the present embodiment includes a swing seat 101 of a balance 40 that adjusts the swing cycle of the ankle 105, a swing stone 102 fixed to the swing seat 101, and a swing stone 102. An ankle 105 in which a rotational force is transmitted from the swing stone 102 to the inner peripheral surface 106 by moving inside, an input claw 110 and an output claw 114 fixed to the ankle 105 so that the relative position can be adjusted, An escape wheel 121 including an escape wheel 122 having an escape tooth 123 intermittently engaged with the protruding claw 114, an escape wheel 122 and an escape wheel 125, an ankle wheel It has 103a and 103b which engage with the sao 109 and regulate the swing angle of the ankle 105. The escape 125 is meshed with the fourth wheel 27.

  The rotation axis C3 of the balance of the balance with hairspring 101, the oscillation axis C1 of the ankle 105, and the rotation axis C2 of the escape gear 121 are arranged on the center line V. The nail 110 of the ankle 105 includes a stop surface 111 as an engaging surface that engages with the locking corner 124 of the escape tooth, an impact surface 113 that receives an impact by the locking corner 124 of the escape tooth, and a stop surface 111. And a locking corner 112 of the nail where the impact surface 113 intersects.

(Description of operation)
Next, the operation of this embodiment will be described with reference to FIGS. FIG. 1 shows that the nail stop surface 111 of the present embodiment is in contact with the locking corner 124 of the escape tooth, and the ankle 105 rotates clockwise about the swing axis C1, and the nail stop surface 111 is It is a figure of the moment when the operation | movement (stop cancellation | release) which pushes back the locking corner 124 of a toothpick counterclockwise is started. FIG. 2 is a diagram of a moment when the stop release ends.

  First, in FIG. 1 and FIG. 2, the hook 109 of the ankle 105 hits the stop 103 a and stops, and the escape gear 122 has a hooking tooth locking corner 124 on the stop surface 111 of the input claw 110 of the ankle 105. It is engaged and stopped. The escape gear 122 is urged clockwise by the power of the barrel 22 being transmitted to the escape gear 125 via the front train wheel.

  Next, the balance 40 is rotated counterclockwise by the energy stored in the hairspring (not shown), and the pallet stone 102 fixed to the balance of the balance of hairspring 101 approaches the anchor 106 of the ankle, and eventually the ankle. It collides with the surface 108 on the protruding claw side of the inner peripheral surface of the box 106. When the surface 108 on the protruding claw side of the inner peripheral surface of the box is subjected to a force from the swing stone 102, the ankle 105 is swung clockwise, and the ankle sao 109 is moved away from the 103a.

  At this time, as shown in FIG. 2, as the ankle 105 swings, the input claw 110 also swings clockwise. The nail locking corner 112 is reached. As described above, the period from the collision of the swing stone 102 to the protruding claw side 108 on the inner peripheral surface of the box 106 until the locking corner 124 of the escape tooth reaches the locking corner 112 of the claw is referred to as the stop release. Call.

  When the stop release is completed, the locking corner 124 of the escape tooth engages with the impact surface 113 of the nail. After the engagement, the locking corner 124 of the hooked tooth slides on the impact surface 113 of the nail so as to apply a clockwise rotational force to the ankle 105. The ankle 105 given a clockwise rotational force by the escape tooth 123 has a counterclockwise rotational force applied to the balance by engaging the claw stone 102 with the claw-side surface 107 of the inner peripheral surface of the box. give.

(Description of the shape of the stop surface of the nail)
Next, the shape of the stop surface 111 of the nail | claw of this embodiment is demonstrated based on FIGS. 1-2.
Here, a coordinate system is considered in which the ankle swing axis C1 is the origin, the center line V is the Y axis, and the horizontal line H passing through the ankle swing axis C1 and perpendicular to the center line V is the X axis.

  At the start of the release of the stop in FIG. 2, the point engaged with the locking corner 124 of the escape tooth on the stop surface 111 of the nail is defined as a stop point 1 and its coordinates are (x1, y1). A normal line 115 is drawn from the stop point 1 to the stop surface 111 of the nail, and a point where a straight line 116 deviated by the friction angle λ2 intersects the center line V is defined as T. T at the start of stop release is T1, and its coordinates are (0, a1). The coordinates of the center of rotation of the escape wheel 121 are (0, b), and the radius of rotation of the locking corner 124 of the escape tooth from the rotation axis C2 is R. Note that the direction of the straight line 116 from the stop point 1 to the intersection point T1 is the torque transmission direction from the escape tooth to the nail. It is assumed that stop cancellation is started and the ankle 105 is rotated clockwise by Δθ. At this time, the stop point 1 (x1, y1) is also rotated by Δθ and moved to (x1 ′, y1 ′). The engagement point between the locking corner 124 of the escape tooth and the nail stop surface 111 at this time is defined as a stop point 2 and its coordinates are defined as (x2, y2). Further, while the ankle rotates by Δθ, the intersection point T1 moves on the Y axis by ΔT toward the ankle swing axis. A point where T1 (0, a1) has moved by ΔT is defined as T2 (0, a2). When Δθ is very small, the slope of the normal drawn from the stop point 2 to the stop surface 111 is the slope of a straight line perpendicular to the straight line connecting (x1 ′, y1 ′) and (x2, y2). It can be regarded as almost equal. In the present embodiment, a straight line deviated from the normal line at the stop point 2 by the friction angle λ2 passes through T2 (0, a2). In this case, the following equation (1) is established.

  Moreover, since the stop point 2 (x2, y2) is on the circumference drawn by the rocking corner 124 of the escape wheel, the following equation (2) is established.

  Further, when the torque ratio of the balance with respect to the ankle at the start of stop release is α, the torque ratio of the balance with the ankle at the end of stop release is β, and the angle at which the ankle swings during the stop release period is θu, ΔT is large. The length is obtained by the following equation (3).

  By solving these equations by the Newton method, the stop point 2 (x2, y2) is obtained.

  Next, it is assumed that the ankle rotates again by Δθ. At this time, the stop point 2 (x2, y2) is also rotated by Δθ and moved to (x2 ′, y2 ′). At this time, the engagement point with the locking corner 124 of the escape tooth on the nail stop surface 111 is defined as a stop point 3, and the coordinates thereof are defined as (x3, y3). T2 moves on the Y axis by ΔT in the direction of the swing axis of the ankle. A point where T2 (0, a2) has moved by ΔT is defined as T3 (0, a3). Then, (x3, y3) can be obtained in the same manner as (x2, y2). By repeating this calculation with Δθ as close to zero as possible, a curve with continuous (xn, yn) is formed. Assuming that the angle of rocking of the ankle during the stop release period is θu, a curve necessary for constructing the stop surface is obtained by repeating the calculation of θu / Δθ times. The shape of the stop surface 111 is formed as a curved surface having such a curve. Let Tu be the intersection T when the ankle swings by θu from the start of stop cancellation.

  Thus, in the present embodiment, the torque transmission direction in which the locking corner 124 of the hook teeth transmits the torque to the stop surface 111 of the nail, the swing axis C1 of the ankle and the rotation axis C2 of the escape wheel 121. The claw stop surface 111 is formed so that the intersection point T where the straight line V passing through the shaft approaches the swing shaft of the ankle from T1 to Tu during the stop cancellation period.

Further, the intersection T is located within a line segment connecting the rotation axis C2 and the swing axis C1 regardless of the rotation angle of the escape wheel during the escape release period of the escape wheel. A claw stop surface 111 is formed.
In the present embodiment, the escape is made of iron, and the nail is made of artificial ruby made of alumina.

(Explanation of effects)
With the nail 110 having the shape of the stop surface 111 as described above, the present embodiment has the following operational effects.
As described above, the torque ratio of the balance with respect to the escape wheel 121 is represented by the product of the torque ratio of the balance with respect to the ankle and the torque ratio of the ankle with respect to the escape wheel. First, when considering the torque ratio of the balance with respect to the ankle, it is as follows.

  Consider transmission of force from the balance stone 102 of the balance to the surface 108 on the protruding claw side of the inner peripheral surface of the box. When viewed statically, the transmission direction of the force from the oscillating stone 102 to the protruding claw side 108 on the inner peripheral surface of the box is determined from the contact point between the oscillating stone 102 and the surface 108 on the protruding claw side of the inner peripheral surface of the box. The direction of the normal line 151 is drawn with respect to the surface 108 on the protruding claw side of the surface, but in this embodiment, the friction between the rock stone 102 and the surface 108 on the protruding claw side of the inner peripheral surface of the box is taken into consideration. However, the transmission direction of the force from the rock stone 102 to the protruding claw-side surface 108 of the inner peripheral surface of the box during the stop cancellation period is deviated from the normal line 151 toward the center of rotation C3 of the balance by the friction angle λ1. Direction. Here, when the intersection of the force transmission direction 152 and the center line V is an intersection S, the torque ratio between the balance with the balance 105 and the balance between the balance center C3 of the balance with the balance S and the swing axis C1 of the ankle is as follows. It is equal to the ratio of the distance to the intersection S. By the fact that the inner peripheral surface of the box 106 is configured as a plane and the pendulum 102 moves on the circumference, the intersection S moves toward the swing axis C1 of the ankle during the period of release of the stop. Go. Therefore, the torque ratio of the balance with respect to the ankle 105 is increased during the stop cancellation period.

  On the other hand, the torque ratio between the ankle and the escape wheel is as follows. First, consider the direction of force transmission from the locking corner 124 of the escape tooth to the nail stop surface 111. When viewed statically, the force transmission direction from the locking corner 124 of the escape tooth to the nail stop surface 111 is the method of pulling from the locking corner 124 of the escape tooth to the entrance nail stop surface 111. In this embodiment, in consideration of the friction between the locking corner 124 of the escape tooth and the nail stop surface 111, in the present embodiment, from the locking corner 124 of the escape tooth during the stop release period. The transmission direction 116 of the force to the claw stop surface 111 is a direction deviated from the normal line 115 toward the rotation center C2 of the escape wheel 121 by the friction angle λ2. Here, if the intersection point of the force transmission direction 116 and the center line V is an intersection point T, the torque ratio between the ankle 105 and the escape wheel 121 is the distance from the swing axis C1 to the intersection point T and the rotation axis C2. It is equal to the ratio of the distance to the intersection T. As shown in FIGS. 1 and 2, in this embodiment, the claw stop surface 111 moves so that the intersection T moves in the direction of the swing axis C <b> 1 of the ankle from the position at the start of stop release during the stop release. Molded. With this configuration, in the present embodiment, the torque ratio of the ankle 105 to the escape wheel 121 decreases during the period of release of the stop at the entering claw.

  It is assumed that the torque ratio of the balance with respect to the ankle 105 is, for example, 0.22 at the start of the stop release in the entering claw 110 and increases to, for example, 0.25 at the end of the stop release. On the other hand, it is assumed that the torque ratio of the ankle 105 to the escape wheel 121 is 0.25, for example, at the end of the stop release in the entry claw 110 and decreases to, for example, 0.22 at the end of the stop release. In this case, the torque ratio of the balance with respect to the escape wheel & pinion 121 is 0.055 both at the start and end of the stop release. Since the torque ratio changes linearly with respect to the swing angle of the ankle 105, in this case, the torque ratio of the balance with respect to the escape wheel 121 does not change at any point during the stop cancellation period. Therefore, since the energy required for the balance with hairspring 40 to reverse the escape wheel & pinion 121 does not increase during the stop cancellation period, the energy loss of the balance 40 can be suppressed.

(Description of pull angle)
In addition, if the escape wheel 121 is shaped so that it does not reverse during the stop release period and the stop surface shape of the claw is formed, the torque ratio of the ankle to the escape wheel becomes 0, thereby the balance of the balance with respect to the escape wheel Since the torque ratio is also 0, the energy loss of the balance with hairspring is minimized, but the escape wheel 121 is formed with the nail stop surface 111 so as to allow reverse rotation during the stop release period in order to ensure safety. ing. The operation is described below.

  When the ankle 105 moves away from 103a due to an external impact during the period in which the anchor 109 is engaged and stopped, the ankle 105 comes into contact with the swing seat 101 and the balance of the balance 40 The vibration period is disturbed and the accuracy of the watch is reduced. In order to prevent this, in order to attract the ankle sao 109 to the back 103a, the force transmission direction from the locking corner 124 of the escape tooth to the nail stop surface 111 is determined by the swing axis C1 of the ankle. It is necessary to pass between the rotary shaft C2 of the hand wheel. That is, the intersection point T is located within the line segment connecting the rotation axis C2 and the swing axis C1 regardless of the rotation angle of the escape wheel during the escape release period of the escape wheel, A claw stop surface 111 is formed. With this configuration, the force transmission direction from the locking corner of the escape tooth gives a counterclockwise torque to the ankle 105, so that the ankle sao 109 is pressed against 103a. The intersection point T is located on the center line V between the ankle swing axis C1 and the escape wheel rotation axis C2. If the intersection point T coincides with the ankle rocking axis C1, the torque ratio becomes zero, and the escape wheel does not rotate backwards even if the ankle rocks. However, as a safety action, the intersection point T needs to be located between the swing shaft C1 of the ankle and the rotation shaft C2 of the escape wheel, so that the ankle 105 and the escape wheel 121 have torque as described above. When a ratio occurs and the ankle 105 swings clockwise, the escape wheel 121 rotates counterclockwise.

(Explanation based on torque ratio diagram)
Here, FIG. 6 is a torque ratio diagram of the balance with the ankle in the conventional example and this embodiment, the horizontal axis is the swing angle of the ankle, and the vertical axis is the value obtained by dividing the balance torque by the torque of the ankle. . The swing angle of the ankle is 0 ° when the ankle sao is on the center line, minus the direction in which the sao enters the claw side, and minus the direction in which the sao falls on the exit claw side. θ1 represents the start point of stop release, and θ2 represents the end point of stop release. The torque ratio on the vertical axis is positive when torque is transmitted from the balance to the ankle. Thus, the torque ratio of the balance with respect to the ankle increases during the stop release.

  FIG. 7 is a torque ratio diagram of an ankle and a escape wheel according to a conventional example, in which the horizontal axis indicates the swing angle of the ankle and the vertical axis indicates a value obtained by dividing the torque of the ankle by the torque of the escape wheel. θ1 represents the start point of stop release, and θ2 represents the end point of stop release. The torque ratio on the vertical axis is positive when torque is transmitted from the ankle to the escape wheel. As described above, in the conventional ankle and escape wheel, the torque ratio of the anchor to the escape wheel increases while the stop is released.

  FIG. 8 is a torque ratio diagram of a balance with a balance wheel according to a conventional example, where the horizontal axis is the swing angle of the ankle, the vertical axis is a value obtained by dividing the torque of the balance by the torque ratio of the ankle, and the torque of the ankle. Is the product of the value divided by the escape wheel torque. θ1 represents the start point of stop release, and θ2 represents the end point of stop release. The torque ratio on the vertical axis is positive when torque is transmitted from the balance to the escape wheel. Thus, in the conventional ankle and escape wheel, the torque ratio of the balance with respect to the escape wheel increases while the stop is released. Since the escape wheel has a constant torque, the torque of the balance necessary for releasing the stop increases during the release of the stop, and the energy loss of the balance increases.

  On the other hand, FIG. 9 is a torque ratio diagram between the ankle and the escape wheel according to the present embodiment. The horizontal axis represents the swing angle of the ankle, and the vertical axis represents the ankle torque divided by the escape wheel torque. Value. θ1 represents the start point of stop release, and θ2 represents the end point of stop release. Thus, in this embodiment, the torque of the ankle with respect to the escape wheel decreases during the stop cancellation period.

  FIG. 10 is a torque ratio diagram of the balance with the balance wheel according to the present embodiment. The horizontal axis represents the swing angle of the ankle, the vertical axis represents the value obtained by dividing the torque of the balance by the torque ratio of the ankle, It is the product of the torque divided by the escape wheel torque. θ1 represents the start point of stop release, and θ2 represents the end point of stop release. The torque ratio on the vertical axis is positive when torque is transmitted from the balance to the escape wheel. Thus, in the ankle and escape wheel of the present embodiment, the torque ratio of the balance with respect to the escape wheel is not increased or the increase can be suppressed during the release of the stop. Since the escape wheel torque is constant, the balance torque necessary for releasing the stop does not increase during the stop release period, and the energy loss of the balance is suppressed.

  As described above, during the stop release period, the increase in the torque ratio of the balance with respect to the ankle is suppressed by the decrease in the torque ratio of the ankle with respect to the escape wheel, and the energy loss of the balance can be suppressed.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. The difference between this embodiment and the first embodiment is that the friction between the locking corner of the escape tooth and the nail stop surface is minute, and the force from the locking corner of the escape tooth to the stop nail stop surface The transmission direction is substantially the same as the normal drawn from the rocking tooth rocking corner to the nail stop surface.

(Description of the shape of the stop surface of the nail)
First, the shape of the stop surface 211 of this embodiment is demonstrated based on FIGS. 3-4.
Here, a coordinate system is considered in which the ankle swing axis C1 is the origin, the center line V is the Y axis, and the horizontal line H passing through the ankle swing axis C1 and perpendicular to the center line V is the X axis.

  A point where the locking corner 224 of the hook teeth on the nail stop surface 211 is engaged at the start of stop release is set as a stop point 1 and its coordinates are set as (x1, y1). Also, a normal line 215 is drawn from the stop point 1 to the stop surface 211 of the nail, a point where the normal line 215 intersects the center line V is T1, and its coordinates are (0, a1). Further, the coordinates of the rotation center of the escape gear are (0, b), and the rotation radius of the locking corner 224 of the escape tooth is R.

  Now, it is assumed that the stop cancellation is started and the ankle is rotated by Δθ. At this time, the stop point 1 (x1, y1) is also rotated by Δθ and moved to (x1 ′, y1 ′). The engagement point between the tip of the escape gear and the engaging claw stop surface at this point is defined as a stop point 2 and its coordinates are defined as (x2, y2). When Δθ is very small, the slope of the normal of the stop surface at stop point 2 is considered to be almost equal to the slope of a straight line perpendicular to the straight line connecting (x1 ′, y1 ′) and (x2, y2). Can do. Further, while the ankle rotates by Δθ, the intersection point T1 moves on the Y axis by ΔT toward the ankle swing axis. A point where T1 (0, a1) has moved by ΔT is defined as T2 (0, a2). Now, when Δθ is very small, the slope of the normal drawn from the stop point 2 to the stop surface 211 is the slope of a straight line perpendicular to the straight line connecting (x1 ′, y1 ′) and (x2, y2). It can be regarded as almost equal. In the present embodiment, the normal line at the stop point 2 passes through T2 (0, a2). In this case, the following equation (4) is established.

  Moreover, since the stop point 2 (x2, y2) is on the circumference drawn by the rocking corner 124 of the escape wheel, the following equation (2) is established.

  By solving these equations as simultaneous equations, the stop point 2 (x2, y2) is obtained.

  Next, it is assumed that the ankle rotates again by Δθ. At this time, the stop point 2 (x2, y2) is also rotated by Δθ and moved to (x2 ′, y2 ′). If the engagement point between the tip of the escape gear and the engaging claw stop surface at this point is the stop point 3 and its coordinates are (x3, y3), (x3, y3) is also obtained in the same manner as the above equation. Can do. By repeating this calculation with Δθ as close to zero as possible, a curve with continuous (xn, yn) is formed. Assuming that the angle of rocking of the ankle during the stop release period is θu, a curve necessary for constructing the stop surface is obtained by repeating the calculation of θu / Δθ times. The shape of the stop surface 211 is formed as a curved surface having such a curve. Let Tu be the intersection T when the ankle swings by θu from the start of stop cancellation.

  As described above, in this embodiment, the torque transmission direction in which the locking corner 224 of the hook teeth transmits torque to the stop surface 211 of the inching claw is that the swing axis C1 of the ankle and the rotation axis C2 of the escape wheel 221 are the same. A claw stop surface 211 is formed so that the intersection point T intersecting with the passing straight line V moves toward the rocking axis of the ankle during the stop cancellation period.

Further, the intersection T is located within a line segment connecting the rotation axis C2 and the swing axis C1 regardless of the rotation angle of the escape wheel during the escape release period of the escape wheel. A claw stop surface 111 is formed.
In the present embodiment, the struggle and the nail are appropriately selected from silicon, zirconia, silicon carbide, and silicon nitride.

(Explanation of effects)
The present embodiment has the following functions and effects by the nail 210 having the shape of the stop surface 211 as described above. Note that points not described below are the same as in the above-described embodiment. As described above, the torque ratio of the balance with respect to the escape wheel 221 is represented by the product of the torque ratio of the balance with respect to the ankle and the torque ratio of the ankle with respect to the escape wheel. First, the torque ratio of the balance with respect to the ankle 205 is considered as follows.

  Consider the transmission of force from the balance stone 202 of the balance to the surface 208 on the protruding claw side of the inner peripheral surface of the box. When viewed statically, the transmission direction of the force from the swing stone 202 to the protruding claw side 208 on the inner peripheral surface of the box is determined from the contact point between the swing stone 202 and the surface 208 on the protruding claw side of the inner peripheral surface of the box. The direction of the normal line 251 is drawn with respect to the surface 208 on the protruding claw side of the surface, but there is friction between the rock stone 202 and the surface 208 on the protruding claw side of the inner peripheral surface of the box. The transmission direction of the force from the stone 202 to the surface 208 on the protruding claw side of the inner circumferential surface of the box is a direction deviated from the normal line 251 toward the rotation center C3 of the balance by the friction angle λ1. Here, assuming that the intersection of the force transmission direction 252 and the center line V is the intersection S, the ratio of the balance between the balance with the balance 205 and the balance between the balance center C3 to S and the swing axis C1 to S of the ankle is as follows. Is equal to the ratio of the distance to By the fact that the inner peripheral surface of the box 206 is constituted by a plane and the pendulum 202 moves on the circumference, the intersection S moves toward the swing axis C1 of the ankle during the period of release of the stop. Go. Accordingly, the torque ratio of the balance with respect to the ankle 205 increases during the stop cancellation period.

On the other hand, the torque ratio between the ankle and the escape wheel is as follows. First, consider the direction of force transmission from the locking corner 224 of the escape tooth to the nail stop surface 211.
In the present embodiment, since there is almost no friction between the locking corner 224 of the escape tooth and the entry pawl stop surface 211, the direction of force transmission from the offset corner 224 of the escape tooth to the entry pawl stop surface 211 is transmitted. Is the direction of the normal line 215 drawn from the locking corner 224 of the escape tooth with respect to the nail stop surface 211. Here, if the intersection of the normal line 215 and the center line V is the intersection point T, the torque ratio between the ankle 205 and the escape wheel 221 is the distance from the swing axis C1 to the intersection point T and the rotation axis C2 to T. Is equal to the distance ratio. As shown in FIGS. 1 and 2, in this embodiment, the claw stop surface 211 is moved so that the intersection T moves in the direction of the swing axis C <b> 1 of the ankle from the position at the start of the stop release during the release of the stop. Molded. With this configuration, in the present embodiment, the torque ratio of the ankle to the escape wheel decreases during the period of stop release.

  It is assumed that the torque ratio of the balance with respect to the ankle 205 is 0.22, for example, at the start of the stop release in the entering claw 210 and increases to, for example, 0.25 at the end of the stop release. On the other hand, it is assumed that the torque ratio of the ankle 205 to the escape wheel 221 is, for example, 0.25 at the end of the stop release in the entering claw 210 and decreases to, for example, 0.22 at the end of the stop release. In this case, the torque ratio of the balance with respect to the escape wheel 221 is 0.055 both at the start and end of the stop release. Since the torque ratio changes linearly with respect to the swing angle of the ankle 205, in this case, the torque ratio of the balance with respect to the escape wheel 221 does not change at any point during the stop release period. Therefore, the energy required for the balance to reverse the escape wheel 221 does not increase during the stop cancellation period, so that the energy loss of the balance 40 can be suppressed.

  In addition, the shape of the stop surface of the nail | claw of each above-mentioned embodiment is measured with a metal microscope or a 2.5-dimensional measuring machine, and from the measured coordinates, the direction in which force is transmitted from the escape tooth to the stop surface of the nail and The intersection T of the center line connecting the swing axis of the ankle and the rotation shaft of the escape wheel is obtained, and the position of the intersection T does not move during the stop release period, or the movement of the intersection T compared to the prior art is The shape of the nail | claw of this embodiment can also be confirmed by being suppressed.

  According to the present invention, in any mechanical timepiece using a Swiss lever escapement, the energy transmission efficiency of the escapement can be improved, and a more accurate mechanical timepiece can be provided.

1 watch 10 movement 30 escapement 40 balance 105 ankle 110 nail 111 stop surface (engagement surface)
121 escape wheel 122 escape gear 115 normal 116 straight line (torque transmission direction)
C1 Ankle swing axis (oscillation axis)
C2 escape wheel rotation axis (rotation axis)
V center line (straight line passing through rotating shaft and swing shaft)
λ2 Friction angle T, T1, Tu Intersection (intersection) between a straight line passing through the rotation axis and the oscillation axis and the torque transmission direction

Claims (6)

A escape gear that can rotate around the rotation axis;
A claw that can be engaged with and disengaged from the escape gear,
In an escapement having a pallet that swings around a swinging shaft with a balance with an ankle that is provided with the engaging claw,
The engagement surface that engages with the escape gear in the engaging claw is an intersection point where a straight line passing through the rotation shaft and the swing shaft intersects with a torque transmission direction in the engagement surface during a stop release period. The escapement is formed in a shape that is displaced so as to approach the swing shaft from the rotation shaft as the escape gear rotates.   The engagement surface such that the torque transmission direction is deviated from a normal line on the engagement surface by a friction angle caused by contact between the engagement claw and the escape gear on the engagement surface. The escapement according to claim 1, wherein the shape is formed.   The escapement according to claim 1, wherein the shape of the engagement surface is formed such that the torque transmission direction is a normal line to the engagement surface.   The shape of the engagement surface is formed so that the intersection is located within a line segment connecting the rotation shaft and the swing shaft regardless of the rotation angle of the escape gear. The escapement according to claim 2 or 3.   A movement comprising the escapement according to any one of claims 1 to 4, a balance that adjusts a swinging period of the ankle, and a gear train that transmits power to the escape gear.   A timepiece having the movement according to claim 5, and an hour hand rotating at a rotational speed regulated by an escapement speed adjusting mechanism including the escapement and the balance.

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