JPH01182787A - Pointer correction mechanism for wrist watch - Google Patents

Abstract

PURPOSE:To contrive to reduce cost by forming a clearance necessary for the removal of a third wheel from the meshing with a minute hand wheel in the correction of a pointer between an engaging section of a third wheel support level and an engaging section of an adjusting member. CONSTITUTION:In a pointer correction state with a winding stem 8 pulled out, an adjusting member 9 is positioned at a point shifted parallel to the direction of a winding stem shaft with engagement between a main plate ridge part 7a and an adjusting member convex part 9b along a slot 7b of the main plate. Under such a condition a clearance B between an outer part 10b of a third wheel support level 10 and a third wheel support lever engaging section 9e of the member 9 is secured in such a manner that the lever 10 can turn to a position where mutual meshing is released completely between a third pinion 14a and a minute hand gear 15b thereby achieving a lowered cost.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a pointer adjustment mechanism for a wristwatch.

[Conventional technology]

As wristwatches mature, costs are rapidly decreasing. A new guideline correction mechanism was required because the cost reduction factors for this cost reduction include reducing the number of parts in the reverse mechanism and using plastic.

The pointer adjustment mechanism of a conventional wristwatch is of a type in which the gear portion of the minute hand wheel and the minute pinion slip, and a cross-sectional view of the mechanism is shown in FIG. During normal movement, from the motor (not shown) to the 5th wheel (not shown), the second wheel 1, the 3rd wheel 2, the minute wheel 6, and the day wheel 4.
The rotation is transmitted to the hour wheel 5 in this order, and the time is displayed. In addition, when adjusting the time, by pulling out the winding stem 6, the pinion 6a formed integrally with the winding stem 6 and the crown gear 4a formed integrally with the day wheel 4 engage with each other, and by turning the winding stem 6, the crown gear 4b is engaged with the crown gear 4a formed integrally with the day wheel 4. to Minkana 6a, and from Hinokana 4C to hour wheel 5.
The rotation is transmitted to the hour and minute hands, and the hour and minute hands are corrected.

At this time, the minute hand gear 6b and the minute pinion 6a are in a slip state due to a slip mechanism based on frictional fitting, and the minute hand gear 6b,
Rotation is not transmitted to the third wheel 2 and second hand wheel 10 wheel train series.

In the case of a structure in which the minute wheel is equipped with a slip mechanism like this, the magnitude of the slip torque must be set at a torque value that will not cause the minute hand to jump when an impact is caused by the unbalanced weight of the minute hand. If it is too large, there will be problems such as needle rotation during pointer correction and wear and tear of the pointer correction wheel train, and management of the slip torque value has been a major factor in increasing costs. In addition, if an attempt was made to make the entire gear train of a three-hand watch from plastic, the minute hand wheel would be put into a slip state to correct the pointers, which would make the teeth of the pointer correction gear train not strong enough, making it difficult to put it to practical use.

As a method to eliminate the slip structure of the minute hand wheel and simplify it, a structure has been proposed in which the engagement between the No. 3 pinion and the minute hand teeth is disengaged by some method when the pointer is adjusted. For example, Japanese Utility Model Publication No. 56-19742 describes a configuration in which the No. 3 pinion is pressed by spring pressure, and when a large torque is applied, the No. 3 pinion escapes against the spring pressure.
No. 8-49281 describes a structure in which the No. 3 pinion escapes via a lever in conjunction with the push and pull of the winding stem.

[Problem to be solved by the invention]

However, in Utility Model Publication No. 56-19742, considering the case of a wristwatch, the module l of each gear is
m / m or less, and if the material is made of plastic, etc., increase the disengagement force from the center gear of the No. 3 pinion (this may cause tooth wear or damage, etc., and conversely, if the disengagement force is reduced, , Normally, a slight impact when carrying the watch can cause the No. 3 pinion to disengage, causing problems such as the minute hand jumping and misaligning the indication.

In addition, in Japanese Utility Model Application Publication No. 58-49281, since the engagement between the No. 3 pinion and the minute hand gear is forcibly completely disengaged when the pointer is being corrected, the amount of rotation of the No. 3 release lever becomes large, and therefore the winding It is necessary to ensure the spring force and displacement of the elastic part that is integrally formed with the No. 3 release lever, which is installed to follow the true operation, so it is necessary to use a metal material for the operating lever. (As a result, it is necessary to strictly control the shape accuracy and surface quality of the operating lever that pivotally supports the lower handle of the third wheel, which affects the life of the mold.

Furthermore, considering the durability of the wheel train, it is necessary to refuel the third wheel on top, which increases costs.

Furthermore, if the mesh is completely disengaged, even a slight impact may cause the minute hand to jump and cause the indication to shift.

The present invention eliminates the above drawbacks and provides a low-cost pointer correction mechanism suitable for wristwatches.

[Means to solve the problem]

The structure of the present invention consists of a plastic-molded third wheel support lever that pivotally supports the lower handle of the third wheel, and a moderation member that positions the winding stem in the axial direction. By regulating the operation of the wheel support lever and setting the winding stem to the pointer correction position, the number 3 wheel support lever can be operated, and the pointer correction can be made by disengaging the minute hand gear and number 3 pinion when correcting the pointer. Similarly, the gap between the moderation member that regulates the third wheel support lever and the third wheel support lever is increased.

〔Example〕

Figures 1 and 3 are a plan view and a sectional view of the main parts of the embodiment of the present invention in the normal hand movement state (when carried), and Figures 2 and 4 are the main parts of the embodiment of the invention in the pointer correction state. Plan view and sectional view, Figure 5,
FIG. 6 shows a sectional view of the operating state of the third wheel and the third wheel support lever and a sectional view of the operating state of the moderation member when the pointer is corrected according to the present invention. 7 is a main plate, 8 is a winding stem, and a moderation member 9 engages with a winding stem engaging portion 9a that engages with a groove portion 8a of the winding stem 8 and a chevron-shaped portion 7a integrally formed on the main plate 7, It has a convex part 9b as a moderation part for positioning, and a dowel 9C that can slide along an elongated hole 7b provided in the main plate 7 parallel to the winding stem axis direction, and when pushing and pulling the winding stem 8, Moderation member 90 elastic part 9d
The convex portion 9b slides along the main plate chevron portion 7a while the winding stem 8 is bent, thereby performing a plurality of positions of the winding stem 8 in the axial direction.

Also, 10 is the third wheel support lever, and the lower handle of the third wheel is connected to the hole 10.
a (shown in FIG. 5), and an integrally formed spring 10b supports a rotating shaft 7C provided on the base plate 7.
The rotational force is applied to the minute wheel in the direction of the minute wheel. At that time, 3
The tip part 10C of the third wheel support lever 10 is in half contact with the stopper wall 7d of the main plate 7, and positioning in the rotational direction is performed. In this state, the third pinion and the second gear are engaged. ing. As shown in FIGS. 1 and 3 (when the watch is carried, the rotation of the rotor 11 is the fifth wheel 12, the seconds wheel 13, the third wheel 14, the minute wheel 15, the date), the hour wheel 16, and the hour wheel 17. Rotation is transmitted to. At that time, the outer shape part 10 as an engaging part with the moderation member 9 of the third wheel support lever 10
d and the third wheel support lever engaging portion 9e of the moderation member 9, the third wheel support lever 10 receives an external impact stronger than the rotational force of the spring 10b, and the third wheel support lever 10 moves in the opposite direction to the minute wheel 15. When it moves, the minute hand gear 15a and the 3rd pinion 14a (5th
(shown in the figure) should be set to such an extent that it will not become disengaged. As shown in FIGS. 2 and 4 (in the pointer correction state where the winding stem 8 is pulled, the moderation member 9 is moved parallel to the winding stem axis direction along the elongated hole 7b of the main plate at the chevron-shaped part of the main plate. 7a and the moderation member convex portion 9b, and in this state, the gap B between the external portion 10d of the third wheel support lever 10 and the third wheel support lever engaging portion 9e of the moderation member 90 is A gap is provided so that the third wheel support lever 10 can be rotated to a position where the pinion 14a and the minute hand gear 15a are completely disengaged from each other.

On the other hand, the winding stem 8 has a winding stem pinion 8C press-fitted into its tip 8b, and the winding stem pinion 8C meshes with a crown gear 16H integrally formed with the rear gear. By turning the winding stem, the winding stem (kana) 8C1 crown gear 16a, and the hinoura wheel 1
Rotation is transmitted from the hour hand 6b to the minute hand 15a and from the hour hand 16C to the hour wheel 17, and the hour and minute hands are corrected.

At that time, the pinion 12a of the fifth wheel 12 and the gear 1 of the second hand wheel 13
3a has a tooth profile that prevents reverse transmission, and the rotation from the fifth wheel 12 to the second wheel 16 during normal hand movement is transmitted, but the rotation from the second wheel 13 to the fifth wheel 12 is prevented by tension engagement. state, and rotation is no longer transmitted.

Further, since the minute hand gear 15b is integrated with the minute pinion 15a, the third pinion 14a receives force from the minute hand gear 15b and moves away from the minute hand gear 15b (arrow C) by the spring 10b.
The third wheel support lever 10 rotates around the rotating shaft 7C against the force, and as shown by the two-dot chain line in FIG. There is no rotation of the gear train.

FIG. 5 is a cross section DD in FIG.
4 is tilted and the No. 3 pinion 14a is disengaged from the minute hand gear 15b, as shown by the two-dot chain line.

FIG. 6 is a cross section EE in FIG. 2, and shows the cross-sectional operating state of the moderation member 9 due to the pushing and pulling of the winding stem 8, and the position of the moderation member 9 when the winding stem is pushed in. is shown by a two-dot chain line, and the position when the winding stem is pulled is shown by a solid line. By using a conductive plastic material for the moderation member 9,
The distal end 9g of the L-shaped portion 9f of the moderation member 9 is slid on the circuit board 18 which has been patterned (not shown), and also serves as a contact member.

As described above, in the simple pointer correction mechanism that eliminates the slip structure between the gear part and pinion part of the minute hand wheel and disengages the third pinion 14a and the minute hand gear 15b, when normally carried, the moderation member 9 This restricts the rotational movement of the third wheel support lever 10, and since the minute hand gear 15b and the third pinion 14a never come out of engagement, there is no fear of misalignment of the instructions.

Therefore, even if the spring 10b of the third wheel support lever is weakened, there is no problem with the function of the stopper.In addition, in the pointer correction state, the moderation spring 9 that regulates the third wheel support lever 10 and the third wheel support The gap between the engagement part of the lever 10 is increased, and the third wheel support lever 10
becomes rotatable around the rotating shaft 7C, and when the minute hand gear 15b and the third pinion 14a disengage from each other due to the rotational force of the minute hand gear 3b during pointer correction, the third wheel support lever 10
Since the spring force is set weak, the needle turning torque is small, so there is no need to worry about the strength of the teeth in the pointer correction gear train and the gear train from the third pinion 14a to the rotor 11. The gear train can easily be made entirely of plastic.

Further, since the third wheel support lever 10 requires only the minimum amount of rotation required to disengage the minute hand gear 15b and the third pinion 14a, the amount of deflection of the spring 10b integrally formed with the third wheel support lever 10 is small. (And, since the spring force can be weakened as described above, the third wheel support lever 10 can be easily made of plastic, and by making the third wheel support lever 10 and the third wheel 14 plastic, the third wheel support lever 10 and the third wheel 14 can be made of plastic. The bearing of the lower handle of the number wheel 14 is made of plastic, making lubrication unnecessary.

In other words, the third wheel support lever 10 that constitutes the pointer correction mechanism
, and by making the entire gear train all plastic, significant cost reductions can be achieved.

Furthermore, by using a conductive plastic material for the moderation member 9, the moderation member 9 which also serves as a contact point can be made of plastic. In addition, a bar (1ab) integrally formed with the third wheel support lever 10, in the normal winding stem position (hand movement state),
It may be eliminated by minimizing or eliminating the gap between the engagement portion between the moderation member 9 and the third wheel support lever 10.

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, it is possible to use highly productive plastic materials for the third wheel support lever that makes up the pointer correction mechanism and all the wheel trains.
In the wheel train, the number of parts can be reduced by integrally molding the gears and pinions for other train wheels, including the minute wheel, which has no slip mechanism, and a significant cost reduction can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the main parts of a watch according to an embodiment of the present invention when it is carried, FIG. FIG. 4 is a partial sectional view of FIG. 2, FIG. 5 is a sectional view taken along line DD in FIG. 2, FIG. 6 is a sectional view taken along line E-E in FIG. FIG. 2 is a sectional view of a main part of a pointer adjustment mechanism of a timepiece. 2.14...3rd car. 6.15...2nd car, 3a, isa...minute kana, ! lb, 15b...Minute hand gear, 4.16...
...Hinoura wheel, 6.8... Winding stem, 9... Moderation member, 10... Third wheel support lever, 14a... Number 3 kana. Figure 6

Claims (1)

[Claims] In a pointer adjustment mechanism of a wristwatch that displays the time using hour and minute hands, at least a winding stem as an external operating member, a moderation member positioned at a plurality of positions in the axial direction of the winding stem, and a minute wheel to which a minute hand is mounted; It consists of a third wheel that engages with the minute wheel, and a third wheel support lever that supports the third wheel and makes it possible to disengage the minute wheel and the third wheel when correcting the pointer. The third wheel support lever includes a rotation center portion serving as a rotation center, a spring portion that acts on the third wheel in the direction of the minute wheel, and an engaging portion that engages with the moderation member. It is formed of a moderation part that positions the winding stem and an engagement part that engages with the third wheel support lever, and when the pointer is corrected, there is a gap between the engagement part of the third wheel support lever and the engagement part of the moderation member. A pointer adjustment mechanism for a wristwatch, characterized in that the mechanism is configured to form a gap necessary for disengaging the third wheel from engagement with the minute hand wheel.