JPH11174169A - Start-stop structure of hour chronograph and spring for slip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To thin a movement. SOLUTION: Around a movement barrel 1, a first hour chronograph wheel 2 is provided, which is connected with friction force of a friction spring 3 to a second hour chronograph intermediate wheel 4 arranged face to face. When stopping the chronograph, a hart cam 63 is fixed to the hammer 64 and so a wheel train to the second hour chronograph intermediate wheel 4 becomes fixed state. The rotation of the movement barrel 1 is transmitted to the first hour chronograph intermediate wheel 2 and so the rotation force conquer the friction force and the friction spring 3 slips. In this manner, by providing a slip mechanism such as the first hour chronograph intermediate wheel around the movement barrel 1, the movement can be made thin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a start / stop structure for a time chronograph, and more particularly, to a start / stop structure for a time chronograph capable of suppressing the loss of barrel movement torque and reducing the movement.

[0002]

2. Description of the Related Art FIG. 6 is a sectional view showing a slip structure of a conventional hour chronograph wheel. The other parts of the chronograph timepiece are well known to those skilled in the art, and thus description and illustration thereof are omitted here. Reference numeral 501 denotes an intermediate hour chronograph wheel. This chronograph intermediate wheel 501
Is rotatably supported by a base plate 550. The rotation from a barrel barrel (not shown) is transmitted to the hour chronograph intermediate wheel 501. Hour chronograph intermediate wheel 501
Is the chronograph gear 502 of the hour chronograph wheel 502
1 is engaged. At this time, the chronograph gear 5021
Is the hour chronograph shaft 502 of the hour chronograph wheel 502
It is rotatably attached to 2.

[0003] A dish-shaped friction spring 503 is fixed to the hour chronograph shaft 5022 (slip structure). Since the friction spring 503 is pressed against the hour chronograph gear 5021, a friction force is generated between the friction spring 503 and the hour spring 503. Further, the hour chronograph axis 502
A heart cam 5023 is attached to one end of 2.
Reference numeral 5024 denotes a hammer that contacts the heart cam 5023. The hammer 5024 is provided at an end of a hammer (not shown). A chronograph hour hand 5025 is attached to the other end of the hour chronograph shaft 5022.

When the chronograph is operated, the hammer 5024 at the end of the hammer is released and the heart cam 5023 is opened. Therefore, the rotation of the barrel wheel is reduced in the intermediate wheel train including the intermediate hour chronograph wheel 501 and transmitted to the hour chronograph gear 5021. The rotation of the hour chronograph gear 5021 is transmitted to the hour chronograph shaft 5022 by the frictional force of the friction spring 503. When the hour chronograph shaft 5022 rotates, the chronograph hour hand 5025 rotates accordingly.

On the other hand, when the chronograph is stopped, the hammer 5024 hits the heart cam 5023 by operating the hammer 5024. Then, a rotational force is applied to the heart cam 5023. The heart cam 5023 and the hour chronograph shaft 5022 are integrated. At this time, the chronograph shaft 5022 and the hour chronograph gear 5021 are connected by a frictional force of a friction spring 503. For this reason, Heartcam 5
When the rotational force of the time chronograph 023 exceeds the frictional force, only the hour chronograph shaft 5022 rotates and the hour chronograph gear 502
1 does not rotate (correctly, it only rotates slowly with the torque from the barrel car). The heart cam 502
3 rotates until the hammer 5024 contacts the double hills above the heart cam. By this rotation, the chronograph hour hand 5025 returns to the zero point.

As described above, when the chronograph is stopped, the heart cam 5023 is forcibly fixed by the hammer 5024. Therefore, even if the rotating force of the barrel wheel is transmitted to the hour chronograph gear 5021, the heart mechanism 5023 slips in the above-mentioned slip mechanism. I will. For this reason, since the rotation of the barrel wheel is not transmitted to the hour chronograph shaft 5022, the chronograph hour hand 5025 does not rotate.

[0007]

However, in the above-described conventional slip structure of a time chronograph wheel, the friction spring 5
Since the hour chronograph shaft 5022 and the hour chronograph gear 5021 are connected to each other by the frictional force of No. 03, when a large inertial force acts on the chronograph hour hand 5025 (for example, when a clock is dropped), There is a problem that the graph hour hand 5025 rotates.

To solve such a problem, the friction spring 503
It is conceivable to increase the urging force. However, increasing the pressing force by the friction spring 503 causes a problem that torque loss of the barrel barrel increases. It is also conceivable to provide a balancer that balances with the chronograph hour hand 5025. However, there is a problem that the movement becomes thick when the balancer is incorporated.

In the conventional slip structure of an hour chronograph wheel, the friction spring is formed in a dish-like shape as shown in FIG. 7A or in a radial direction as shown in FIG. He used multiple legs. However,
The dish-shaped friction spring 703 has a problem that it is difficult to adjust the pressing force and cannot perform a stable slip. Further, in the friction spring 803 having a plurality of feet extending in the radial direction, the length of the feet is short, so that the frictional force becomes too strong and the adjustment thereof is difficult.

Accordingly, the present invention has been made in view of the above, and firstly, it is an object of the present invention to provide a start / stop structure for a chronograph when the torque loss of a barrel car can be suppressed and the movement can be thinned. With the goal. Second, it is another object of the present invention to provide a slip spring that can perform stable slip and easily adjust a frictional force.

[0011]

In order to achieve the above-mentioned object, according to a first aspect of the present invention, a start / stop structure for a time chronograph includes a barrel car for accommodating a mainspring serving as a power source, and a chronograph hour hand. The chronograph wheel and the rotation of the barrel wheel are transmitted to the hour chronograph wheel, and the first temporary chronograph intermediate wheel provided around the barrel wheel and the first temporary chronograph intermediate wheel are coaxial and independent. A second intermediate chronograph wheel train including a second hour chronograph intermediate wheel rotating, and the first temporary chronograph intermediate wheel and the second hour chronograph intermediate wheel are connected by a frictional force of a spring member when the chronograph operates. And a slip mechanism in which when the chronograph is stopped, the spring member slips and rotation transmission between the first temporary intermediate chronograph wheel and the second intermediate chronograph wheel is interrupted. It is intended.

The rotation from the barrel wheel is transmitted to the hour chronograph wheel by the hour chronograph intermediate wheel train. At this time, the chronograph intermediate wheel train, in particular, the first temporary chronograph intermediate wheel provided around the barrel wheel and the second intermediate wheel. If a slip mechanism is provided between the temporary intermediate chronograph wheel and the second hour chronograph intermediate wheel that rotates coaxially and independently, the rotation of the barrel wheel is transmitted when the chronograph is activated and slips when the chronograph is stopped. The transmission of rotation from the barrel car can be cut off. Thus, if the slip mechanism is provided around the barrel car, it is possible to suppress an increase in the thickness of the movement.

[0013] Further, according to a second aspect of the present invention, there is provided a time chronograph starting / stopping structure, comprising a barrel car for accommodating a mainspring serving as a power source;
A time chronograph wheel to which a chronograph hour hand is attached, a rotation of the barrel wheel transmitted to the hour chronograph wheel, a first temporary chronograph intermediate wheel provided around the barrel wheel and the first temporary chronograph An hour chronograph intermediate wheel train that includes a second hour chronograph intermediate wheel that rotates coaxially and independently with the intermediate wheel, and a spring member fixed to the second hour chronograph intermediate wheel to attach the spring member to the first temporary When the chronograph is in operation, the first temporary chronograph intermediate wheel and the second hour chronograph intermediate wheel are connected by the frictional force of the spring member when the chronograph is operating, and the spring member and the second hour chronograph intermediate wheel are stopped when the chronograph stops. And a slip mechanism for interrupting the rotation transmission by causing a slip with the intermediate hour chronograph wheel.

In this slip mechanism, a spring member is fixed to the second hour intermediate chronograph wheel, and this spring member is urged to a first temporary intermediate chronograph wheel provided around the barrel car, and its frictional force causes rotation. I try to communicate. When a rotational force exceeding the frictional force is applied, the spring member and the first temporary chronograph intermediate wheel slip, so that the rotation transmission is interrupted. Thus, if the slip mechanism is provided around the barrel car, it is possible to suppress an increase in the thickness of the movement.

Further, the slip spring according to claim 3 is
A plurality of feet having at least a sled portion are provided radially from the center of rotation, and the feet are bent substantially in the direction of the rotation axis.

Since the foot has at least the sled, the foot can be extended to the outer periphery of the spring. For this reason, an appropriate frictional force can be obtained, and the adjustment can be simplified. As a result, a stable slip can be obtained.

The slip spring according to claim 4 is
A plurality of feet are provided radially from a center part which is fixed to the first rotating member and becomes a center of rotation, and an inverted bowl-shaped part is formed near the end of the foot, and this foot is moved substantially in the axial direction. The bent portion presses the inverted bowl-shaped portion against the second rotating member facing the first rotating member, and transmits the rotation from the first rotating member to the second rotating member by the frictional force. Is added to cause a slip between the first rotating member and the second rotating member.

First, by providing the feet in a rotating radial manner,
The foot can be lengthened before reaching the outer periphery of the spring. Next, by forming the inverted bowl-shaped portion near the end of the foot portion, it is possible to maintain good contact with the second rotating member. For this reason, an appropriate frictional force can be obtained, and the adjustment can be simplified. Also, since the contact state with the second rotating member is good,
A stable slip can be obtained.

The slip spring according to claim 5 is
A plurality of feet are provided in a radial direction from a center portion which is fixed to the first rotating member and becomes a center of rotation, and branch feet are respectively provided in a circumferential direction from the plurality of feet, and end portions of the branch feet An inverted bowl-shaped portion is formed in the vicinity, and the branch leg is bent substantially in the axial direction to press the inverted bowl-shaped portion against a second rotating member opposed to the first rotating member, and the frictional force causes the second bowl to rotate. The rotation is transmitted from the one rotating member to the second rotating member, and a slip is generated between the first rotating member and the second rotating member by applying a rotating force equal to or more than the frictional force.

By providing the feet in the radial direction and providing the branch feet in the circumferential direction from substantially the ends of the feet, the length of the feet can be increased even if the diameter is small. Further, by forming the inverted bowl-shaped portion near the end of the branch leg, the contact state with the second rotating member can be favorably maintained. For this reason, an appropriate frictional force can be obtained, and the adjustment can be simplified. In addition, since the inverted bowl-shaped portion improves the contact state with the second rotating member, a stable slip can be obtained.

According to a sixth aspect of the present invention, there is provided the hour chronograph starting / stopping structure, wherein the slipping spring is used as the spring member in the hour chronograph starting / stopping structure.
5).

If the above-mentioned slipping spring is used as the spring member, fine adjustment of the frictional force becomes possible and variation in the slip torque is reduced, so that the torque loss from the barrel wheel to the hour chronograph wheel can be suppressed.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. The present invention is not limited by the embodiment. FIG. 1 is a sectional view showing a start / stop structure of a time chronograph according to the present invention. FIG.
FIG. 2 is a top view showing the start / stop structure of the chronograph shown in FIG.

At this time, in the chronograph start / stop structure 100, reference numeral 1 denotes a barrel car containing a mainspring serving as power. The barrel gear 11 of the barrel wheel 1 meshes with the first temporary chronograph intermediate wheel 2. The first temporary chronograph intermediate wheel 2 is located around the barrel wheel 1 and is rotatably attached to the first pin 21. The friction spring 3 is pinched by screwing the first pin 21 to the second pin 41. The friction spring 3 is pressed against the first chronograph intermediate wheel 2. The second hour intermediate chronograph wheel 4 is fixed to a second pin 41. The second pin 41 is rotatably supported by the main plate 101. The second hour intermediate chronograph wheel 4 meshes with the third hour intermediate chronograph wheel 5. The third hour intermediate chronograph wheel 5 rotates about the third pin 51 as an axis. The third pin 51 is fixed to the main plate 101.

Reference numeral 6 denotes an hour chronograph wheel. The hour chronograph wheel 6 includes a main plate 101 and a chronograph receiver 10.
2 so as to be rotatably supported. The chronograph gear 61 of the hour chronograph wheel 6 meshes with the third hour chronograph intermediate wheel 5. A heart cam 63 is attached to one end of a shaft 62 of the hour chronograph wheel 6. Reference numeral 64 denotes a hammer that contacts the heart cam 63. The hammer 64 corresponds to an end of the hammer 65. A chronograph hour hand 66 is attached to the other end of the shaft 62 of the hour chronograph wheel 6. Note that a dial and a case are omitted for convenience of description.

FIG. 3 is a top view showing the friction spring 3.
FIG. 4 is a perspective view showing the friction spring 3 shown in FIG.
The center part 31 of the friction spring 3 is provided with a hole 32 through which the screw part 22 of the first pin 21 is inserted.
, Three feet 33 extend in the radial direction. Each leg 33 is provided with a branch leg 34 in the circumferential direction. The forked part 34 is subjected to bending in the direction of the rotation axis in the middle thereof. An inverted bowl-shaped portion 35 is formed at an end of the branch leg portion 34. The friction spring 3 is formed by pressing a thin plate.

The friction spring 3 passes the screw portion 22 of the first pin 21 through the hole 32 of the center portion 31 and screwes the first pin 21 to the second pin 41 to pinch and fix the peripheral edge of the hole 32. .
In this fixed state, the inverted bowl-shaped portion 35 contacts the lower surface of the first temporary chronograph intermediate wheel 2. Since the branch leg 34 is bent, a pressing force is generated by the elasticity of the branch leg 34. Further, the friction spring 3 is not limited to the shapes shown in FIGS. For example, as shown in FIG. 5A, three legs 36 are provided in a rotating radial manner, and the inverted bowl-shaped portion 3 is provided at the end thereof.
5 may be provided. The foot portion 36 of the friction spring is bent substantially in the axial direction from the middle or from the base. Further, as shown in FIG. 3B, three feet 37 curved at two places are provided.
And an inverted bowl-shaped portion 35 may be provided at the end. Also in this case, it is bent substantially in the axial direction from the middle of the foot 37 or from the base.

Next, the start / stop structure 10 of this chronograph
The operation of 0 will be described. [During chronograph operation] As shown in FIG. 2 and FIG.
During operation of the chronograph, the hammer 65 is separated from the heart cam 63, so that the heart cam 63 is released from the forcibly fixed state. On the other hand, the rotation of the barrel wheel 1 is transmitted to the first temporary chronograph intermediate wheel 2. The first intermediate chronograph wheel 2 and the second hour chronograph intermediate wheel 4 are connected by a friction spring 3. That is, since the top of the inverted bowl-shaped portion 35 provided on the friction spring 3 is pressed against the lower surface of the first temporary chronograph intermediate wheel 2 by the elasticity of the branch leg portion 34, the frictional force generated by this causes the first force. The middle hour chronograph wheel 2 and the second hour chronograph intermediate wheel 4 are connected. Therefore, the rotation of the first temporary chronograph intermediate wheel 2 is transmitted to the second hour chronograph intermediate wheel 4.

When the second hour intermediate chronograph wheel 4 rotates, it is transmitted to the third hour intermediate chronograph wheel 5 which meshes therewith. The third hour chronograph intermediate wheel 5 is an hour chronograph wheel 6
, The rotation of the third hour chronograph intermediate wheel 5 is transmitted to the hour chronograph wheel 6. Since the heart cam 63 attached to the shaft 62 of the hour chronograph wheel 6 is open as described above, the hour chronograph wheel 6 can be rotated. When the hour chronograph wheel 6 rotates, the chronograph hour hand 66 attached to this shaft rotates.

[When the chronograph is stopped] When the chronograph is stopped, the hammer 64 contacts the heart cam 63 with the hammer 64 operating in the direction of the arrow in FIG. As a result, a rotational force is applied to the heart cam 63. Since the heart cam 63 and the shaft 62 of the hour chronograph wheel 6 are integral, when the heart cam 63 rotates, the hour chronograph wheel 6 also rotates.
The rotation direction is determined by the relative positional relationship between the heart cam 63 and the hammer 64. By forcibly rotating the heart cam 63, the rotation of the hour chronograph wheel 6 is changed to the second hour chronograph intermediate wheel 4 via the third hour chronograph intermediate wheel 5.
It is transmitted to. On the other hand, rotation from the barrel car 1 is transmitted to the intermediate chronograph intermediate wheel 2.

The second intermediate chronograph wheel 4 and the first intermediate chronograph wheel 2 are connected by a friction spring 3. Since the force for rotating the heart cam 63 is larger than the frictional force, a slip occurs between the friction spring 3 and the first temporary chronograph intermediate wheel 2. For this reason, the second hour intermediate chronograph wheel 4 rotates independently without being restrained by the first temporary intermediate chronograph wheel 2. The heart cam 63 rotates until the hammer 64 comes into contact with the double hills above the heart cam. As a result, the chronograph hour hand 66 returns to the zero point.

When the chronograph is stopped, the hammer 64 of the hammer 65 is in contact with the heart cam 63.
For this reason, since the heart cam 63 is fixed, the chronograph wheel 6 is also fixed and does not rotate when it becomes coaxial. The hour chronograph wheel 61 meshes with the third hour chronograph intermediate wheel 5, and the third hour chronograph intermediate wheel 5 meshes with the second hour chronograph intermediate wheel 4, so that the hour chronograph wheel 6 rotates. If not, the intermediate chronograph wheel 4 does not rotate.

On the other hand, the rotation of the barrel wheel 1 is transmitted to the first intermediate chronograph wheel 2 which is in mesh with the barrel gear 11. However, as described above, since the second hour chronograph intermediate wheel 4 connected by the friction spring 3 is fixed, when the rotational force of the first temporary chronograph intermediate wheel 2 exceeds the frictional force, the friction spring Slip between 3 When the chronograph is stopped, the slip is continued.

As described above, according to the time chronograph start / stop structure 100 of the present invention, the first temporary chronograph intermediate wheel 2 is disposed around the barrel barrel 1, and the first temporary chronograph intermediate wheel 2 is provided.
The friction spring 3 was provided between the second hour chronograph intermediate wheel 4 and the second hour chronograph intermediate wheel 4. That is, since the slip mechanism is provided around the barrel car 1, the movement can be made thinner as compared with the case where the hour chronograph wheel 6 is provided with the slip mechanism.

Further, the elasticity of the forefoot part 34 causes the inverted bowl-shaped part 3
5 is brought into contact with the lower side of the first temporary chronograph intermediate wheel 2 so as to obtain a frictional force, so that the contact state with the first temporary chronograph intermediate wheel 2 is improved, and there is a small variation. A friction force is obtained. Further, the adjustment of the frictional force is simplified.

[0036]

As described above, according to the time chronograph starting / stopping structure of the present invention (claim 1), the first temporary chronograph intermediate wheel and the first temporary chronograph arranged around the barrel box. Since the slip mechanism is provided between the intermediate wheel and the second hour chronograph intermediate wheel that rotates independently and coaxially, the movement can be made thinner.

[0037] In the hour chronograph start / stop structure (claim 2) of the present invention, a slip mechanism is provided on the hour chronograph intermediate wheel train provided around the barrel barrel, and a spring member is provided on the second hour chronograph intermediate wheel. The spring member is fixed, and the spring member is urged to the first intermediate chronograph wheel to transmit rotation by the frictional force. By providing the slip mechanism around the barrel car, the movement can be made thinner.

A slip spring according to the following invention (claim 3)
According to the above, at least a plurality of feet having a sled portion are provided radially from the center of rotation, and the feet are bent substantially in the direction of the rotation axis, so that the feet are extended to the outer periphery of the spring. Can be. For this reason, an appropriate friction force can be obtained and the adjustment thereof can be easily performed, and a stable slip can be obtained.

A slipping spring according to the next invention (claim 4)
In Japanese Patent Application Laid-Open No. H11-229, the feet are provided in a rotating radial manner, and the feet are long before reaching the outer periphery of the spring. In addition, an inverted bowl-shaped portion is formed near the end of the foot to maintain good contact with the second rotating member. In this way, an appropriate frictional force can be obtained and the adjustment can be simplified. Further, since the contact state with the second rotating member is improved, a stable slip can be obtained.

A slip spring according to the next invention (claim 5)
According to the method, a foot portion is provided in a radial direction, a branch foot portion is provided in a circumferential direction from a substantially end portion of the foot portion, and an inverted bowl-shaped portion is formed near an end portion of the branch foot portion. However, the foot length can be increased, and the state of contact with the second rotating member can be kept good. For this reason, an appropriate frictional force can be obtained, and the adjustment can be simplified.
In addition, the state of contact with the second rotating member is improved by the inverted bowl-shaped portion, so that a stable slip can be obtained.

According to the time chronograph starting / stopping structure of the invention (claim 6), since the above-mentioned slipping spring is used as the spring member, fine adjustment of the frictional force becomes possible, and variation in the slip torque is reduced. it can. Therefore, torque loss from the barrel wheel to the hour chronograph wheel can be suppressed.

[0042]

[Brief description of the drawings]

FIG. 1 is a sectional view showing a start / stop structure of a time chronograph according to the present invention.

FIG. 2 is a top view showing a start / stop structure of the chronograph shown in FIG.

FIG. 3 is a top view showing the friction spring shown in FIG. 1;

FIG. 4 is a perspective view showing the friction spring shown in FIG. 3;

FIG. 5 is a perspective view showing a modification of the friction spring.

FIG. 6 is a sectional view showing a slip structure of a conventional hour chronograph wheel.

FIG. 7 is a perspective view showing an example of a conventional friction spring.

[Explanation of symbols]

 100 hour chronograph starting / stopping structure 1 barrel wheel 2 first temporary chronograph intermediate wheel 3 friction spring 33 foot 34 branch foot 35 inverted bowl-shaped portion 4 2nd hour chronograph intermediate wheel 5 3rd hour chronograph intermediate wheel 6 o'clock chronograph wheel 63 heart cam 64 hammer 65 hammer hammer 66 hour hand for chronograph

Claims (6)

[Claims] 1. A barrel wheel for accommodating a mainspring serving as a power source, a hour chronograph wheel to which a chronograph hour hand is attached, and transmitting rotation of the barrel wheel to the hour chronograph wheel and surrounding the barrel wheel. A chronograph intermediate wheel train including a first temporary chronograph intermediate wheel and a second hour chronograph intermediate wheel that rotates coaxially and independently of the first temporary chronograph intermediate wheel; and A temporary intermediate chronograph wheel and a second hour chronograph intermediate wheel are connected by a frictional force of a spring member, and when the chronograph stops, the spring member slips and the first temporary chronograph intermediate wheel and the second hour chronograph intermediate wheel. A start / stop structure for a time chronograph, comprising: a slip mechanism for interrupting rotation transmission with a vehicle. 2. A barrel wheel for accommodating a mainspring serving as a power source, a hour chronograph wheel to which a chronograph hour hand is attached, and transmitting rotation of the barrel wheel to the hour chronograph wheel and surrounding the barrel wheel. A second intermediate chronograph wheel train including a first intermediate chronograph intermediate wheel and a second intermediate chronograph intermediate wheel rotating independently and coaxially with the first intermediate chronograph intermediate wheel; and the second hour chronograph. A spring member is fixed to the intermediate wheel and the spring member is pressed against the first temporary chronograph intermediate wheel. When the chronograph is operated, the first temporary chronograph intermediate wheel and the second hour chronograph are driven by frictional force of the spring member. And a slip mechanism for interrupting rotation transmission by causing a slip between the spring member and the second hour chronograph intermediate wheel when the chronograph is stopped. The starting and stopping structure of the chronograph. 3. A slipping spring, wherein a plurality of legs having at least a sled portion are provided radially from a rotation center portion, and the legs are bent substantially in a rotation axis direction. 4. A plurality of feet are radially provided from a center portion fixed to the first rotating member and serving as a center of rotation, and an inverted bowl-shaped portion is formed near an end of the feet, and the feet are formed. Is bent substantially in the axial direction, and the inverted bowl-shaped portion is pressed against the second rotating member facing the first rotating member, and the frictional force transmits rotation from the first rotating member to the second rotating member, whereby the friction A slip spring, wherein a slip is generated between the first rotating member and the second rotating member by applying a rotating force equal to or greater than a force. 5. A plurality of feet are provided in a radial direction from a central portion fixed to a first rotating member and serving as a center of rotation, and a plurality of branches are provided in a circumferential direction from the plurality of feet, respectively. An inverted bowl-shaped part is formed near the end of the foot, and the branch leg is bent substantially in the axial direction to press the inverted bowl-shaped part against the second rotating member facing the first rotating member. By transmitting rotation from the first rotating member to the second rotating member by frictional force, a slip is generated between the first rotating member and the second rotating member by applying a rotating force greater than the frictional force. And a spring for slip. 6. The method according to claim 3, wherein the spring member is used.
3. The time chronograph starting / stopping structure according to claim 1 or 2, wherein the slipping spring according to any one of the above is used.