EP2224294A1 - Mechanism for setting the minute hand of a timepiece with automatic return-to-zero of the seconds hand - Google Patents

Abstract

The clock has an adjusting shaft (16) coupled with a center-wheel group (40) of a clockwork mechanism such that rotation of the shaft adjusts a minute indicator. The shaft co-operates with an arm (18), intermediate element (20), and zero resetting arm (22) for driving second indicator in a zero position when moving the shaft in an adjusting position. The wheel group includes resting mechanisms that enable 60 resting positions, so that the minute indicator is adjusted between 60 positions of the minute indicator in a minute index by the rotation of the shaft in the adjusting position.

Description

The present invention relates to a timepiece with at least one minute hand and a second hand and a movement, which has a mechanism for setting the minute hand. This mechanism comprises a control shaft, which is adjustable by pulling or pressing a crown in the axial direction between a normal position and a parking position. The control shaft is coupled in its parking position in such a way with a minute gear group of the movement that a rotation of the actuating shaft causes an adjustment of the minute hand. In addition, the actuating shaft cooperates with a zeroing mechanism, which drives the second hand in its zero position upon movement of the actuating shaft in the parking position, blocking it in this zero position, while the actuating shaft is in the parking position, and him in a movement of the actuating shaft back in releases its normal position again.

Watches with such mechanisms are already known from the prior art. For example, the CH 18774/71 a watch provided with such a zeroing mechanism. If you pull the crown to set the time, the second hand will be set to zero and held in that position until the crown is pressed again.

A disadvantage of the known mechanisms is that the interaction between the second and minute hands is lost during the adjustment process. If the user rotates the crown and thus the actuating shaft with the crown pulled (adjusting shaft in the setting position), the minute tube on which the minute hand is seated is rotated via a corresponding gear train. The minute hand may be in an arbitrary position after the adjustment process, for example in the middle between two minute indices. If the movement runs after pressing When the crown comes up again, the second hand starts from zero while the minute hand starts from any position. Minute hand and second hand thus run asynchronously.

The present invention has for its object to overcome this disadvantage.

This object is achieved on the basis of the preamble of claim 1 by the characterizing features of claim 1.

The locking mechanism according to the invention, with which the minute wheel group of the movement is provided, allows 60 locking positions. Turning the control shaft in its position causes the minute tube and thus the minute hand to move step by step so that the minute hand can only be moved from one minute index to the next. So the minute hand never comes to lie between two minute indices. If you press the crown so that the movement starts again, the minute hand starts from a minute index, and the second hand from zero, and the two hands are in sync with it.

Advantageous embodiments of the invention are described in the subclaims and in the description which follows.

According to a particularly advantageous embodiment of the invention, the locking mechanism comprises a concentric with a minute wheel arranged and provided with 60 locking lugs on its inner circumference locking ring and at least one arranged within the locking ring, pivotally mounted latch. This latch is acted upon by a spring element radially outward and locked with the locking lugs of the locking ring. If the adjusting shaft is turned when the crown is pulled, then the locking ring is rotated in relation to the locking pawl. The latch is pressed by the shape of the latching lugs formed on the inside of the latching ring against the force of the spring element which pushes it outwards, in each case radially inward, and then locks again with the next latching lug. You get so on simple and reliable way of gradually adjusting the minute hand.

Preferably, the latching mechanism comprises two symmetrically arranged latching pawls, which are each acted upon by an arm of the spring element radially outward. The spring element is otherwise preferably formed in two parts to facilitate its installation.

According to a particularly advantageous embodiment of the invention, the zeroing mechanism comprises a pivotable by an axial movement of the actuating lever, which pivots a zeroing lever on a movement of the actuating shaft in the adjusting position via an intermediate member, which in turn actuates a zeroing drive, which drives the second hand in its zero position.

The pivotable lever is preferably an angle lever and has a toothing. This toothing can interact with a corresponding toothing of the intermediate member.

Preferably, the intermediate member on a cam-like footprint and / or a toothing, which cooperates with the zeroing lever. The pivotal movement of the angle lever is then first transmitted to the intermediate member via the interlocking teeth, which performs a rotational movement. About the footprint and / or the second toothing of the intermediate member of the zero lever is pivoted.

The zeroing lever then actuates the zeroing drive, which preferably comprises a heart-shaped control curve. Such heart-shaped control curves, also referred to as second-seconds, for zeroing the second hand are well known from the prior art.

According to a preferred embodiment of the invention, the zeroing lever is formed with two arms, wherein a first arm actuates the zeroing drive, and a second arm actuates a stopping mechanism for stopping a balance of the clock. Here is the two-armed lever preferably designed so that when pulling the crown of the stop mechanism is already operated shortly before the zeroing drive. The zero position of the second hand is therefore only when the second hand is no longer moved by the movement.

According to a particularly advantageous embodiment of the invention, the zeroing lever has a spring-trained area. In the case of a two-armed zeroing lever, it is particularly advantageous if the first arm, i. the one arm which actuates the zeroing drive, is resilient. Due to the suspension, the force acting on the zeroing drive can be dosed appropriately, namely in such a way that a zero position is reliably achieved, but the secondary gear group is not damaged.

In order to decouple the adjustment of the minute hand from the power flow, the small ground gear group and the second wheel group of the movement are preferably carried out in duplicate. In each case, one part lies in the power flow between the barrel and balance, while the other part is directly or indirectly coupled with the minute wheel in.

More specifically, for example, the minor wheel group of the movement comprise two superimposed and coupled via a friction clutch low floor wheels, with a first Kleinbodenrad with the minutes group is in communication, and a second Kleinbodenrad sitting in the power flow between a barrel and a balance. Similarly, the second wheel group of the movement can comprise two superimposed and coupled to each other via a friction clutch second wheels, with a first second wheel with the zero drive and the Kleinödenradgruppe with the minutes wheel group in conjunction, and a second second wheel in the power flow between the barrel and balance sits. When the actuating shaft is in its normal position, the two low-floor wheels coupled via the friction clutch and the two second wheels each move together. When the control shaft is in its position, is Turn the first second wheel over the zero setting drive to set the second hand to zero. At the same time, the stop mechanism blocks the balance and thus the power flow. The two halves of the second wheel group and the low-wheel gear group, which are in operative connection with the zero-setting drive, now move in relation to their respective other halves located in the power flow.

When the crown is pressed again, the zeroing drive and the balance are released again. The friction clutches ensure a play-free starting of the seconds and minute hands synchronized thanks to the mechanism according to the invention.

Hereinafter, a preferred embodiment of the invention will be described with reference to the accompanying drawings.

• Fig. 1: eine perspektivische Ansicht eines Teils eines Uhrwerks einer Uhr, wobei eine Stellwelle sich in ihrer Normalposition befindet;
• Fig. 2A: eine seitliche Ansicht des gleichen Uhrwerkteils, wobei die Stellwelle sich in ihrer Normalposition befindet;
• Fig. 2B: eine Draufsicht des gleichen Uhrwerkteils, wobei die Stellwelle sich in ihrer Normalposition befindet;
• Fig. 3A: die gleiche Ansicht wie Fig. 2A, wobei die Stellwelle sich nun in ihrer Stellposition befindet;
• Fig. 3B: die gleiche Ansicht wie Fig. 2B, wobei die Stellwelle sich nun in ihrer Stellposition befindet;
• Fig. 4A: eine Draufsicht auf eine Minutenradgruppe des Uhrwerkteils aus den Fig. 1 bis 3;
• Fig. 4B: einen Schnitt entlang der Linie B-B in Fig. 4A;
• Fig. 4C: eine Explosionsdarstellung der Minutenradgruppe aus den Fig. 4A und 4B.

The figures show in detail:

• Fig. 1 a perspective view of a part of a clockwork of a clock, wherein a control shaft is in its normal position;
• Fig. 2A a side view of the same clockwork part, wherein the actuating shaft is in its normal position;
• Fig. 2B a plan view of the same movement part, wherein the control shaft is in its normal position;
• Fig. 3A : the same view as Fig. 2A , wherein the control shaft is now in its parking position;
• Fig. 3B : the same view as Fig. 2B , wherein the control shaft is now in its parking position;
• Fig. 4A : A plan view of a minute wheel group of the clockwork part from the Fig. 1 to 3 ;
• Fig. 4B : a section along the line BB in Fig. 4A ;
• Fig. 4C : An exploded view of the minute wheel group from the FIGS. 4A and 4B ,

Fig. 1A shows a perspective view of a part of a clockwork of a clock according to the invention. The same clockwork part is in the Fig. 2A and 3A in top view and in the Fig. 2B and 3B shown in a side view. The adjusting shaft 16 is in FIGS. 2A and 2B as in Fig. 1 in their normal position while in FIGS. 3A and 3B axially displaced outwards into its parking position. When the control shaft 16, as in the Fig. 1 . 2A and 2B , in its normal position, the movement runs normally. The details of the function of the movement are well known to the skilled person and not the subject of the present invention, so that they will not be described here. For the meaning of the reference numerals not explained in detail below, reference is made to the list of reference numerals following the description of the figures.

As in particular in the lateral views of the Fig. 2A and 3A detects, a Kleinbodenradgruppe 34 of the movement comprises two superposed and over a plate spring 35 coupled to each other small ground wheels 34a, 34b. The upper Kleinbodenrad 34a communicates with a minutes wheel group 40 in connection, while the lower Kleinbodenrad 34b sits in the power flow between a barrel 10 and a balance wheel 26.

A second wheel group 32 of the movement is also made in two parts. Here, too, is a lower part with a second wheel 32a in the power flow between the barrel 10 and the balance 26. This lower second wheel 32 is also coupled via a friction clutch, such as a plate spring or a spreading spring with an upper second wheel 32b, which with a zeroing heart 32c and a second axis 32d is rotatably connected. The upper part of the second wheel group, ie the upper second wheel 32b, the zeroing heart 32c and the second axle 32d, communicate with the minute wheel group 40 via the minor ground gear group 34.

When depressed crown an angle lever 18 holds with an 18a toothing an intermediate member 20 with an engaging in the toothing 18a of the angle lever 18 teeth 20a. The intermediate member 20 in turn holds on a second toothing 20b a zeroing lever 22. In this case, a toothing 22a of the zeroing lever 22 with the second toothing 20b of the intermediate member into engagement. The zeroing lever 22 is divided into a zeroing 22b and a stop arm 22c, whose function in consideration of the Fig. 3B will become clear. If the actuating shaft 16 is in its normal position, both arms 22b, 22c are each held in a neutral position.

When pulling the crown is, ie when adjusting the control shaft 16 in its parking position (see. FIGS. 3A and 3B The intermediate lever 20 pivots the zeroing lever 22 via the second toothing 20c and the footprint 20b. The zeroing arm 22b of the zeroing lever 22 is thereby counter to that of the second wheel group 32 corresponding Nullstellherz 32 c pressed, and the second axis 32 d with the second hand is moved to the zero position and fixed there.

At the same time, a stop arm 22c of the zeroing lever 22 releases a brake lever 23 shortly before reaching the effective range of the zeroing heart 32c, which in turn releases a brake spring 24 which then stops the balance 26 and thus the movement.

The zeroing arm 22b of the zeroing lever 22 is comparatively thin and thus resilient. The force with which the nulling arm 22b acts on the nulling heart 32c is metered by this suspension, and the exact shape of the nulling arm 22b and thus the spring force is chosen so that the zero position of the second hand, not shown in the figures, works reliably, the second wheel group 32 but not damaged. Due to the specially arranged toothing 20b, 22a between the intermediate member 20 and the Zeroing lever 22, the torque that builds up by the spring force of the zeroing arm 22 b, not transmitted to the angle lever 18 on. The actuator shaft 16 and thus the crown can thus be easily rotated to set the time without the actuator automatically moves back to its normal position.

When turning the control shaft 16, the minute hand, not shown, is rotated over a minute tube 43. The rotation of the control shaft 16 is transmitted in a known manner via a corresponding gear train (inter alia change wheel 36) to the minute tube 43. By in the Figs. 4A, 4B and 4C more precisely detectable locking mechanism of the minute wheel group 40, this movement is gradual from one minute index to the next. How to get into the Figs. 4A, 4B and 4C sees, a locking ring 44 is provided, which is concentric with the minute wheel 42, wherein the outer diameter of the locking ring 44 is slightly smaller than that of the externally toothed minute wheel 42. The locking ring is rotatably connected to the minute tube 43 (see FIG. Fig. 4B ) and is provided on its inner circumference with 60 locking lugs 45. These locking lugs 45 define in cooperation with two latches 46 the 60 possible positions of the minute tube 43 and thus the minute hand. The two detents 46 are each pivotally mounted on a journal 47 on the minute wheel 42. A simplified to simplify the assembly in two parts spreading spring 48, which sits centrally on the minutes wheel 42, pushes the bearing pin 47 opposite end of the two locking blades 46 to the outside, so that the two locking blades 46 each with a contact surface 46a on a locking lug 45 of the locking ring 44 come to the plant.

If the adjusting shaft 16 is turned when the crown is pulled, then the minute tube 43 is rotated with the locking ring 44 via the change gear 36 and the gear train connecting it with the control shaft 16 with respect to the minute wheel 42 with its latching pawls 46. Since the Nullstellherz 32c is blocked, the minute wheel 42 is thereby from the Kleinbodenradgruppe 34th blocked (cf. FIGS. 3A and 3B ). The latches 46 are thereby pressed by the locking lugs 45 against the force of the outwardly urging spring element 48 radially inward, and slide with the contact surfaces 46 a along the respective latch 45, so that the minute tube is rotated by 1/60 before they Latch 46 latch again with the next latch 45. The minute hand can thus be adjusted only gradually from one minute index to the next.

Pressing the crown and thus the control shaft 16 back to its normal position (see. Fig. 1 . 2A and 2B By engaging the teeth 20b, 22a between the intermediate member 20 and the reset lever 22, the reset lever 22 is again guided back to its neutral starting position. The zeroing arm 22b of the zeroing lever 22 releases the zeroing heart 32c on the second wheel group 32 again. At the same time, the brake lever 23 is also returned to its neutral position by the stop arm 22c of the zeroing lever 22, and the brake spring 24 is deflected away from the balance wheel 26 so that the balance wheel 26 is released again and the movement starts again.

The friction clutches, which couple the two low-end wheels 34a, 34b and the lower (32a) to the upper part (32b, 32c, 32d) of the second wheel group, ensure a play-free starting of the minute and second displays. Thanks to the zeroing mechanism, the second hand starts from zero, while the minute hand starts from a minute index thanks to the locking mechanism. The two hands are thus synchronized.

LIST OF REFERENCE NUMBERS

10

barrel

12

Clutch lever spring

14

clutch lever

16

actuating shaft

18

bell crank

18a

gearing

20

intermediary

20a

gearing

20b

gearing

20c

footprint

22

Reset lever

22a

gearing

22b

Nullstellarm

22c

stopping arm

23

brake lever

24

brake spring

26

balance

28

anchor

30

escape wheel

32

Sekundenradgruppe

32a

lower second wheel

32b

upper second wheel

32c

Zeroing heart

32d

second axis

34

Kleinbodenradgruppe

34a

Third wheel

34b

Third wheel

35

Belleville spring

36

change gear

40

Minutenradgruppe

42

minute wheel

43

cannon

44

locking ring

45

locking lug

46

latch

46a

contact surface

47

pivot

48

spring element

Claims (13)

Clock with at least one minute hand and a second hand and a movement, which has a mechanism for adjusting the minute hand, this mechanism comprising a control shaft (16) which is adjustable in the axial direction between a normal position and a setting position, wherein the actuating shaft (16) is coupled in its parking position with a minute wheel group (40) of the movement such that a rotation of the actuating shaft (16) causes an adjustment of the minute hand, and further with a zeroing mechanism (18, 20, 22) cooperates, which upon movement of the actuating shaft (16) drives the second hand to its neutral position in the parking position, blocks it in this zero position while the actuating shaft (16) is in the actuating position and releases it back to its normal position upon movement of the actuating shaft (16), characterized .
that the Minutenradgruppe (40) of the movement with a latching mechanism (44, 45, 46) is provided which 60 detent positions allowed, so that the minute hand by rotating the control shaft situated in its locking position (16) between 60 positions of the minute hand on a respective Minute index is adjustable. Clock according to claim 1, characterized
in that the latching mechanism comprises a latching ring (44) arranged concentrically with a minute wheel and provided with 60 latching lugs (45) on its inner circumference, and at least one latching pawl (46) arranged within the latching ring (44), the latter being supported by a spring element (48 ) is acted upon radially outwards, and with the latching lugs (45) of the locking ring (44) locked. Clock according to claim 2, characterized
in that the latching mechanism comprises two symmetrically arranged latching pawls (46), which are each acted upon radially outwards by one arm of the spring element (48). Clock according to one of the preceding claims, characterized
in that the zeroing mechanism comprises a lever (18) pivotable by an axial movement of the actuating shaft, which pivots a zeroing lever (22) which actuates a zeroing drive (32c) when the adjusting shaft (16) moves into the adjusting position via an intermediate member (20). which drives the second hand to its zero position. Clock according to claim 4, characterized
that the pivotable lever is an angle lever (18) and has a toothing (18a). Clock according to claim 4 or 5, characterized
in that the intermediate member (20) has a toothing (20a) which cooperates with a toothing of the pivotable lever (18a). Clock according to one of claims 4 to 6, characterized
in that the intermediate member (20) has a footprint (20c) and / or a toothing (20b) which cooperates with the zeroing lever (22). Clock according to one of claims 4 to 7, characterized
that the zero actuator comprises a heart-shaped actuating cam (32c). Clock according to one of claims 4 to 8, characterized
in that the zeroing lever (22) has two arms, a first arm (22b) actuating the zero setting drive (32c), and a second arm (22c) a stopper mechanism (23, 24) for stopping a balance (26) of the watch is operated. Clock according to one of claims 4 to 9, characterized
that the zeroing lever (22) has a resiliently formed area. Clock according to claim 9, characterized
that the first arm (22b) of the zero setting lever (22) is resilient. Clock according to one of the preceding claims, characterized
in that a small-diameter wheel group (34) of the movement comprises two small-base wheels (34a, 34b) arranged one above the other and coupled to one another via a friction clutch (35), wherein a first small-plate wheel (34a) is connected to the minute-wheel group (40), and a second small-plate wheel ( 34b) in the power flow between a barrel (10) and a balance (26) sits. Clock according to one of the preceding claims, characterized
that a Sekundenradgruppe (32) of the movement of two superposed and coupled to one another via a friction clutch seconds wheels (32a, 32b), wherein a first second wheel (32b) with a zero actuator (32c) and a Kleinbodenradgruppe (34) with the Minutenradgruppe (40 ) is in communication, and a second second wheel (32a) in the power flow between a barrel (10) and a balance (26) sits.

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