US3672150A

US3672150A - Display dial assembly for timepiece

Info

Publication number: US3672150A
Application number: US101668A
Authority: US
Inventors: Tetuya Yasuda; Hidetaka Tutiya; Takeshi Mori
Original assignee: Citizen Watch Co Ltd
Current assignee: Citizen Watch Co Ltd
Priority date: 1969-12-25
Filing date: 1970-12-28
Publication date: 1972-06-27
Anticipated expiration: 1989-06-27
Also published as: GB1284508A

Abstract

The present invention relates to a display dial, such as a day calendar display dial, for a timepiece. The improvement comprises the provision of at least two resilient arms made integral therewith and adapted for easy and positive engagement with a positioning peripheral groove formed on the mounting shaft for the dial.

Description

United States Patent Yasuda et a1.

[451 June 27,1972

DISPLAY DIAL ASSEMBLY FOR TIMEPIECE Tetuya Yasuda; Hidetaka Tutiya; Takeshi Mori, all of Tokyo, Japan Citizen Watch Company Limited, Tokyo, Japan Filed: Dec. 28, 1970 App1.No.: 101,668

Inventors:

Assignee:

Foreign Application Priority Data Dec. 25, 1969 Japan ..44/l04545 June 30, 1970 Japan ..45/65l51 Nov. 12, 1970 Japan ..45/111594 US. Cl. ..58/5, 58/58, 58/152 R Int. Cl. ..G04b 19/24 Field of Search ..58/45, 42.5, 43, 125 B, 126 A,

[56] References Cited UNITED STATES PATENTS 2,976,672 3/1961 Ducommun ..58/5 X 3,452,535 7/1969 Cabantous et al ..58/4 R Primary Examiner-Richard B. Wilkinson Assistant Examiner--Edith C. Simmons Attorney-Sughrue, Rothwell, Mion, Zinn & Macpeak [57] ABSTRACT The present invention relates to a display dial, such as a day calendar display dial, for a timepiece.

The improvement comprises the provision of at least two resilient arms made integral therewith and adapted for easy and positive engagement with a positioning peripheral groove formed on the mounting shaft for the dial.

7 Clains, 13 Drawing Figures PATENTEDJUNN m2 SHEET 10F 4 FIG.

FIG. 2

IOc L I lOc IOb DISPLAY DIAL ASSEMBLY FOR TIMEPIECE The present invention relates to a display dial, such as a day calendar display dial, for a timepiece.

It is the main object of the invention to provide a display dial of the above kind which can be easily attached to and detached from a mounting shaft.

A further object of the invention is to provide a display dial of. the above kind which is highly easy to manufacture and very cheep in its manufacturing cost.

Thesev and further objects, features and advantages of the inventionwill become more apparent when reading the followingdetailed description of several preferred embodiments of the inventionby reference to the accompanying drawings.

In the drawings:

FIG. 1 is aplan view of a first preferred embodiment of the invention, 9

FIG. 2 is a sectional view taken along a section line shown in FIG. 1.

FIG. 3 is'an'axial section of part of a watch to which the pinion-dial assembly is fitted, said dial serving as a day calender display dial for said watch.

FIGS. 4 and 5 are similar views to FIGS. 1 and 2, showing, however, a preferred second embodiment of the invention.

FIGS. 6 and7 are similar views to FIGS. 1 and 2, showing, however, a preferred third embodiment of the invention.

FIGS. 8 and 9 are similar views to FIGS. 1 and 2, showing, however, a preferred fourth embodiment of the invention.

2 FIGS. 10 and 11 are similar views to FIGS. 1 and2, showing, however, a preferred fifth embodiment of the invention.

FIGS. 12 and 13 are similar views to FIGS. 1 and 2, show ing, however, a preferred sixth embodiment of the invention.

- Referring now to FIGS. 1 and 2, the first embodiment will be described hereinbelow in detail.

' In these figures, numeral 10 represents a display dial in its entirety. This diall fl represents a front surface 10a on which a series of radially arranged display marks or symbols such'as names of the calendar days: Monday, Tuesday and the like, when the dialis used as the day calendar display dial in a timepiece.

The dial 104s formed integrally and rigidly with a plurality of radially. arranged pinion teeth 10b which have been produced by a pressing and punching job, said teeth being positioned at a different levelfrom that of the dial proper l0.

Thedial I0 is formedwitha central opening 10f and a pair of substantially concentrically arrangedresilient holder arms lfl'c and 10c' whichare positioned substantially in a rotational symmetry'with-each-other. These arms and the central opening areformed by the said pressing and punching job. These

arms

10 and 10c are formed each with an inside circular are shaped edge 100' or 10c, respectively, adapted for snuglyengaging with the bottom of a circular groove 3a of a mounting shaft 3 the cross-sectional outline of which is shown at 3 is shown in FIGS. 1 and 2 byachain-dottedline, respectively. In practice, however, thisshaft 11 is formed into a tube shaft as most clearly seen from FIG. 3. Each. of these resilient arcshaped armsv 10c and 100' is formed on its inside periphery with a recess 10 or 10:, respectively, which serves for dismantling serviceby receiving a manual tool tip.

The dial 10 is formed with a plurality of radially arranged perforations 103 after the punch-formation of downwardly ofi'set radial pinion teeth 10b.

In FIG. 3, part of a timepiece movement is shown in its axial section. In this movement, the dial. 10 is utilized as day calendar display dial.

Inthis timepiece movement, numeral 12 represents part of a convenu'onal lower plate of the movement; 13 shows a second wheel of the gear train of the movement; 14 represents a cannon pinion. The shaft 11 which has been referred to in the foregoing FIGS. 1 and 2, constitutes practically the hollow shaft part of a cannonwheel.

Further in FIG. 3, numeral 16 represents a guard plate which is rigid with the lower plate 12 and positioned slightly above the cannon wheel 15, so as to prevent any stipping disengagement of the wheel 15 from the position in the timepiece movement.

A day dial drive wheel 17 is rotatably mounted arounda pivot 18 fixedly mounted on the guard plate 16. Numeral 19 represents a conventional time-indicator dial of the timepiece, said dial being shown only partially andsaid drive wheel 17 being in mesh with said pinion teeth 10b.

' Numeral 20 represents a conventional secondhand arbor which is, as conventionally, rotatably mounted in the shaft of center wheel 13. The top end of shaft 11 is chamfered at 1 lb.

The members l2, l3, 14, ll; 15, 16, 17, I8, 19 and 20 are of conventional design and arrangement so that no further description of their 1 and and function would-be necessary for better understanding of the invention.

The gear-dialassembly 10; 10b accordingto thisinvention can be manufactured easily on an industrial production scale at a low cost by relying substantially upon the pressing and stamping job and substantially in a single manufacturing step.

When it is intended to fit the aforementioned pinion-dial as, sembly in position in the timepiece movement as shown in FIG. 3, the assembly shown in FIGS. 1 and 2 is inserted from upper onto the hollow shaft part 11 by utilizing the central opening 10]. At first, the resilient holder arms 10:: and 100' willbeslightly and resiliently expanded outwardly by contact of the respective arc-shaped inner edge parts IOd'and 10d with the chamfered shaft end 111:. By moving slippingly the dial l0 along-the outside surface of shaft part 11, until it comes to the groove 11a, the dial can be snapped into the groove by its resilient arms 10c and 100', thus the dial being firmly positioned at the height of the groove Ila. Therefore, otherwise possible axial shift of the dial [0 relative to the cannon wheel shaft can be positivelyprevented and the dial can be accurately positioned at the specifically destined position in the timepiece movement.

- For removal of the dial 10 from position, it is sufilcient to insert a tool tip from upper througha central dial opening 190 into one of the recesses-10: or 10c and to exert a slight manual bending moment, so as to expand the resiliently gripping arm or 100', and to slide the dial upward.

The second embodiment is shown in FIGS. 4 and 5. In this embodiment, similar parts are denoted with respective same reference numerals, yet each being added with 20 for easier comparison andbetter and quicker understanding of the invention, regardless, however, of occasional minor configurational difference as well as occasional minor functional-difference from those of the foregoing first embodiment. v

The display dial 30 has generally a circular disc shape which is formed at its outer periphery with a plurality of or more specifically seven sector-like radial projections 31 and substantially rectangular recesses 32 arranged alternatively one after another. Each projection 31 may bear a day calendar notification, although not shown.

The dial 30 is formed with a pluralityof radially arranged openings 30 g for providing enough material for the press-fob. mation of downwardly off-set positioned, resilient gripper arms 30c and 300. These arms 30c and 300' are formed and arranged in a perfectly symmetrical way about a section line 5-5.

These resilient gripper arms 30c and 300' are concentrically arranged within the area of a central opening 30f when seen in the plan view shown in FIG. 4, the respective root portions of these gripper arms are integral with an offset inner control disc area 33. The dial 30 so far shown and described has been fabricated into its final shape by a single pressing and punching job.

The

gripper arms

30c and 30c are formed with respective tool-tip reception recesses 30c and 30a in the similar way as before, but, dispensed with the shah-gripping arc-shaped edges 30d and 30d. In this case, these arms 30c and 300' embrace resiliently the mounting shaft, equally shown by chaindotted line 1 l as before. This shaft 11 is embraced in this case at three

points

34, 35 and 36, of which the former two points tip ends, while the remaining contact point 36 is selected at the common root portion of these gripper arms. It should be noted that in the present embodiment, no pinion teeth such as at b in the foregoing first embodiment is provided.

The operation of the present embodiment will be self-explanatory by consideration of the foregoing structural description thereof in combination with the whole detailed description on the first embodiment.

The third embodiment is shown in FIGS. 6 and 7. In this case, similar parts as before are shown by respective same reference numerals, each being, however, attached with 30.

The display dial in this embodiment is shown at 40 in its entirety. Resilient gripper arms 40c and 400' are arranged in the same level to that of main body of the dial 40. These arms 40c and 400' are arranged in a complete circle which is, however, broken at 100. The common root portion at 101 is made integral with the main body of the dial 40 which has a central opening shown at 40f formed substantially into a star.

Gear teeth 40b are formed on the punch-out lower disc portion shown generally at 102 and having naturally a star shape corresponding that of the central opening 405. Projections 40b of this star fonned by the punched-out lower disc 102 form in combination a plurality of pinion teeth similar to those shown at 10b in FIGS. 1-3.

The display dial 40 fitted and formed with several functional parts so far shown and described has been manufactured by a single pressing and cut-out job on a press.

The function of the present embodiment is substantially similar to that of the foregoing first embodiment.

The fourth embodiment is shown in FIGS. 8 and 9. In this embodimennsimilar constituents are shown with respective same references as those of the first embodiment, yet each being added with 40 for clear identification.

The fourth embodiment of the invention is shown in FIGS. 8 and 9, wherein similar parts with those of the first embodiment are denoted with respective same reference numerals, yet each being added with 40 for clear identification.

The display 50 is formed with a plurality of radially arranged cutouts 103-106 and a central opening 50f. A pair of resilient gripper arms 50c and 500' are made integral with the main body of the dial 50, each of these arms covering a central angle of about 150 and the free ends of these arms are extending a common diameter of the dial 50 which diameter coincides in FIG. 8 with the section line 8-8, the inner extremities of these resilient arms having each a slightly concave gripper edges 107 and 108 adapted for resiliently contacting with the shaft 11 so as to establish a tongue-and-groove connection therewith.

Along the inner peripheral edge defining the central opening 50], there is arranged a plurality of radially arranged recesses 50h, each having a semicircular configuration when seen in FIG. 8, for receiving a pin 107a to be described.

Numeral 109 represents a star wheel made of a plastic resin material and having a plurality of radial tooth projections 1090 made integral therewith. This star wheel 109 is formed with a central opening defined a concentric flange 109d neighboring to a concentric circular groove 10%. On the upper surface of the star wheel 109, there is formed a plurality of upwardly projecting pins 109a arranged in a concentric circle, each of these pins being received in said receiving recesses 50h, as was briefly referred to hereinabove, when the star wheel has been assembled together concentrically from below with the display dial 50.

Upon mechanically assembling the star wheel with the dial as shown, the upwardly projecting end of each of these pins 1094 is subjected to heat and pressure, so as to provide a flared heat seal connection, as shown at 109a. The star wheel 109 is formed with a center opening 109i for passing the shaft 1 I with substantial radial idle plays.

As seen from the foregoing, the dial-star wheel assembly provides a highly rigidly united combination by relatively simple and easy manufacturing process. The easy and positive attachment and detachment of the dial-star wheel assembly to and from the shaft 11 can be assured as in the foregoing several embodiments.

The fifth embodiment of the invention is shown in FIGS. 10 and 11 in combination. In this embodiment, similar parts as those of the first embodiment are denoted with respective same reference numerals, each being, however, added with 50 for clearer identification and comparison.

The display dial, generally shown at 60, is formed with a central opening for allowing to pass a mounting shaft 1 I as before. The dial is formed with two pairs of resilient and mutually opposed arms, each having substantially a L-shape when seen in their elevational view shown in FIG. 11. Each of these arms 600 is formed with an arc shaped contacting edges 6011 in close proximity of the free end of the arm substantially in an inclined manner and adapted for contacting with the shaft groove which is similar to that shown at 114 in the first embodiment, although not specifically shown.

The shaft 11 is positioned by contact with arc-shaped concave edges 60g defining substantial part of said center opening 60f. As seen main or working part of each of the resilient arms 600 is positioned in a downwardly off-set position from the main body of the display dial 60. A plurality of gear pins 60b are radially provided in an concentric manner around the center opening 60f, so as to provide practically the function of a pinion. All these constituents, except pinion pins 60b, have been formed by a single pressing and cutting-out step on a press, not shown.

The attaching operation of the present dial 60 can be made in the similar manner as before. In order to detatch the dial from engagement with the shafi, a pari of resilient arms 60c when seen in the lateral direction to the section line 11-11 are forcibly expanded by a pencette or the like tool.

The sixth embodiment of the invention is shown in FIGS. 12 and 13.

In the present embodiment, similar parts to those used in the first embodiment are denoted with respective same reference numerals, each being, however, attached with 60 for easier identification and comparison.

In the present embodiment, three resilient arms 700 are formed and arranged substantially tangentially to a center opening 70f adapted for reception of a shaft denoted again with the same reference numeral 11. There are formed three recesses 70g in close proximity to the tip ends of the resilient arms 70c adapted for reception of a pincette or the like tool used for the disengaging service.

The operation can be easily understood from the foregoing description, especially from that concerning the foregoing fifih embodiment.

In all the foregoing embodiments, the dial can be rotated with slight friction around the shaft when the dial is operated The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A display dial, such as day calendar display dial, for a timepiece having a central bore for detachable reception of a groove shaft, said dial being characterized by the provision of at least two resilient arms made integral with the dial, each of said arm having a concavely curved portion adapted for pressure contact with the bottom of a peripheral groove formed on said shaft.

2. A display dial as claimed in claim 1, wherein a pair of said resilient arms are arranged in a rotary symmetry to each other.

3. A display dial as claimed in claim I, wherein a pair of said resilient arms are arranged in a symmetry to each other.

4 A display dial as claimed in claim 1, wherein said dial is formed with a concentric and integral pinion teeth made from the same material of the dial.

5. A display dial as claimed in claim I, wherein a separate star wheel made of a plastic material is attached firmly to said dial by fusing a plurality of connection pins.

6. A display dial as claimed in claim 1, wherein said resilient arms are arranged substantially tangentially to said central bore.

7. A display dial as claimed in claim 1, wherein two pairs of said resilient arms are provided, each pair being arranged in line to each other and substantially tangentially to said central bore.

Claims

3. A display dial as claimed in claim 1, wherein a pair of said resilient arms are arranged in a symmetry to each other. 4 A display dial as claimed in claim 1, wherein said dial is formed with a concentric and integral pinion teeth made from the same material of the dial.

5. A display dial as claimed in claim 1, wherein a separate star wheel made of a plastic material is attached firmly to said dial by fusing a plurality of connection pins.