US3335562A

US3335562A - Anchor escapement for timepieces

Info

Publication number: US3335562A
Application number: US436777A
Authority: US
Inventors: Schneider Jean-Claude
Original assignee: Fabrique dHorlogerie CHS Tissot et Fils SA
Current assignee: Tissot SA
Priority date: 1965-03-03
Filing date: 1965-03-03
Publication date: 1967-08-15
Anticipated expiration: 1984-08-15

Description

g- 1967 JEAN-CLAUDE SCHNEIDER 3,335,562

ANCHOR ESCAPEMENT FOR TIMEPIECES Filed March 3, 1965 2 Sheets-Sheet 1 INVEN TOR 1 TEAN-CLnuJc SJINHJEIZ @zgmzimwmw Wis {M g 1957 JEAN-CLAUDE SCHNEIDER 3,335,552

ANCHOR ESCAPEMENT FOR TIMEPIECES Filed March 5, 1965 2 Sheets-Sheet 3 &

M 7/ m V5 III: w m /m 1 2 n 0/ n) w y N n y) f m Z INVENTOR IEAN- CLHLIJE Schweidan 22.2mm Mum His United States Patent 3,335,562 ANCHOR ESCAPEMENT FOR TIMEPIECES Jean-Claude Schneider, La-Chaux-de-Fonds Neuenburg,

Switzerland, assignor to Fabrique dHorlogerie Chs.

Tissot et Fils S.A., Le Locle, Neuenburg, Switzerland,

a corporation of Switzerland Filed Mar. 3, 1965, Ser. No. 436,777 Claims. (Cl. 58122) The present invention has reference to an improved anchor or lever escapement for timepieces, specially clockworks, wherein the anchor body is equipped with shoulder means and limit stops, the limit stops cooperating with an escape wheel in order to limit the amplitude of vibration or oscillation of the aforesaid anchor body.

Escapements of this type have been developed with the intention of simplifying assembly of the escapement in that there was avoided the use of reversing or turning pegs which generally are arranged to both sides of the anchor staff and are embedded in a plate. The known anchors which are equipped with limit stops cooperable with the escapement wheel possess adjustable shoulders, this being the case with most conventional anchors. These shoulders are secured by means of suitable adhesive material in recesses inset in the anchor body. Since the limit stops function to act upon the drive surface of one of the teeth of the escapement wheel at the moment that the appropriate shoulder interrupts rotational movement of the escapement wheel at the desired position, it is necessary that the limit stops are adjusted in accordance with the momentary position of the corresponding shoulder.

In some cases the function of the limit stop is taken up itself by the shoulder. This shoulder then abuts against the base of the tooth, before the surface or plane of rest of the tooth impacts against the plane of rest of the shoulder. This means that in this case the base portion of the tooth must be differently constructed than is otherwise usual. However, if the limit stops differ from the shoulder elements then they cannot be formed by appropriate portions of the anchor body. This is so because the adjustment of the impact position in correlation with the temporary position of the shoulder would then no longer be possible. In order to circumvent this difliculty it has been attempted to equip the anchor with two adjustable elements. Each of both of the anchor claws therefore possesses two recesses which are arranged in the direct neighborhood of one another and in which always one element engages, such element generally being formed of ruby stone or glass. In so doing, one of both of these elements partakes the function of a shoulder, the other the function of the limit stop. Each limit stop is disposed in the region of the corresponding shoulder at the side opposite the direction of rotation of the escapement wheel. Due to such arrangement the construction of the anchor is more difiicult and complicated. Consequently, the discussed physical construction can hardly be embodied in smaller timepieces, such as for instance used in wrist watches.

Accordingly, it is a primary object of the present invention to provide an improved construction of anchor escapement of the previously mentioned type, the technical construction and assembly of which are simpler than with conventional constructions, however without impairing the precision of the entire assembly with regard to faultless operation.

Another important object of the present invention is concerned with an improved construction of anchor escapement for timepieces which is highly reliable in operation, easy to assemble, economical to manufacture as well as quite robust.

' Still a further extremely important object of this in- 3,335,562 Patented Aug. 15, 1967 vention has reference to an improved anchor escapement of the type described wherein the anchor member incorporates drive shoulder means and limit stops, wherein the anchor member, the shoulder means and limit stops are integral with one another, thereby considerably simplifying manufacture and assembly of the escapement.

In order to implement these and still further objects of the invention, the anchor escapement designed according to the teachings of the present invention is generally characterized by the features that the shoulders and limit stops are formed from one piece together with the anchor body, and further, that the momentary contact or working surfaces of the anchor body are defined by peripheral surface elements of the aforementioned piece which are substantially axially parallely disposed to the axis of rotation of the anchor body.

Other features, objects and advantages of the present invention will become apparent by reference to the following detailed description and drawings in which:

FIGURE 1 is an elevational view of a preferred embodiment of inventive anchor escapement; and

FIGURE 2 is a cross-sectional view of the device of FIGURE 1 substantially taken along the line IIII thereof, and wherein certain elements are particularly illustrated in detail.

Describing now the drawings and, in particular, directing attention to FIGURE 1 there is shown therein an anchor member or body 1 which is a single piece worked by a punching and planing operation from a metal plate. This anchor body 1 cooperates with an escape or escapement wheel 2 of conventional construction. This escape ment wheel 2 is provided with a plurality of spaced teeth 3, each tooth possessing a drive surface 4. Moreover, this anchor body 1 possesses two claws or pallets 5. In the neighborhood of the free end portions 5a of each of these claws 5 there is located a respective shoulder 6 bounded by a linear face or edge 7. Each shoulder 6 is directed such that the face or edge 7 providing a working surface abuts against the drive surface 4 of a tooth 3 of the escapement wheel 2 at the moment when the anchor body 1 is just located in one of its outermost or terminal oscillating positions. It will be appreciated that each shoulder 6 provides limit stop means for the anchor body 1. Apart from the physical structure just described, each claw 5 possesses a further shoulder 8 having the function of a drive shoulder and which according to the illustration of FIGURE 1 for the claw 5 at the right side is pressed upwardly to the right. Each shoulder 8 is disposed at the right of its associated shoulder 6, however at the same claw 5. Furthermore, each of the shoulders 8 possesses a flat planed or trued drive or rear working surface 9 possessing the function of a drive surface for the drive shoulder 8. Additionally, each such shoulder 8 has a lateral surface 10 which, with respect to the rear. drive surface 9, forms an exactly defined angle. This lateral or side surface 10 provides a rest or stop surface for its associated drive shoulder 8.

The anchor body 1 has an elongated portion which is designated as the anchor rod or staff 11. At the outermost end of the anchor rod 11 there is located a widened terminal piece 12 possessing an opening 13. This opening 13 forms an inlet for the entrainment means 24 of the spring pin or lug and which is advantageously manufactured in the same punching and truing operation where also the shoulders 8 and 6 are produced. The widened end or terminal piece 12 of the anchor rod 11 is furthermore worked into such a configuration that its forward face or edge 14 at the highest location possesses a projection 15 constructed in the form of a nose member. Due to milling out a circular-shaped edge 16 there remains only a thin wall 17 at the widened terminal piece 12 in front of the opening 13. The nose member 15 is located substantially centrally of the forward face 14 of this thin wall 17. Moreover, the lower face or wall 17a of the thin wall 17 aligns with the lower boundary surface 1a of the anchor body 1.

By further referring to FIGURE 1 it will be apparent that two symmetrically arranged elements forming horns 18 are bounded by the circular-shaped edges 16 between the opening 13 and the forward face 14 of the widened terminal piece 12. The described escapement has the function of controlling the vibrations or oscillations of a balance wheel 19, partially visible in FIGURE 2. This figure shows that a shaft 20 of the balance wheel 19 supports a ring element 21 incorporating two collars 21a and 21b providing a large cam disk 22 and smaller cam disk 23 respectively. The upper circular-shaped cam disk 22, constructed as the large cam disk, possesses a laterally protruding entrainment member 24 engageable with the opening 13 of the terminalpiece 12. This entrainment member 24 can be obtained by punching and planing or truing operations. A recess 25 formed at the marginal zone of the small cam disk 23 enables entry of the nose member 15.

The oscillatory or rocking movement of the anchor body 1 is ensured by a support member 26 produced at an automatic lathe for instance. This support member 26 incorporates two support arms 39, and a pin or peg stub 27, preferably integral therewith, which is arranged at the central region thereof and which engages in a bore 28 of the anchor body 1. Support member 26 is connected to a plate 29 of the timepiece by means of screws 30 or equivalent fastening expedients. By means of these screws 30 a small plate 31 extending above the anchor body 1 is connected to the support member 26. Furthermore, the support member 26 is provided at its upper surface with an annular or ring rib 32 which extends substan-' tially concentric to the pin stub or shaft 27 about which the anchor body 1 oscillates. Anchor body 1 bears by means of its anchor staff or rod 11 upon this annular rib 32. As should be apparent by inspecting FIGURE 2, the clearance or play of the anchor body 1 towards the top is formed by the spacing between the upper plane surface 33 of the annular or ring rib 32 and the likewise fiat constructed surface 34 of the small plate 31. Additionally, the support member 26 has a preferably integral cylindrical-shaped pin or peg stub 35, the function of which will be considered shortly.

Both the arrangement as well as also the alignment of the support member 26 upon or with respect to the plate 29 is eifected by the cylindrical-shaped pin 35 extending out of the support member 26 and by a cylindrical head bolt 36. The plate 29 is provided with two bores 37 and 38, bore 37 receiving the pin 35 and the other bore 38 the bolt 36. The first bore 37 of both bores 37 and 38 is accommodated without play to the diameter of the pin 35, whereas the second bore 38 is accommodated by frictional contact to the diameter of the pin 36. The bolt 36 is pressed into the bore 38, whereas the widened cylinder head 43 of bolt 36 engaging between the support arms 39 ensures for an exact orientation or alignment of the support member 26.

As will be recalled the described anchor body 1 is advantageously manufactured from a single piece. The operative steps necessary for the manufacture of this member can be reduced to a minimum. This anchor body or member 1 can be completely manufactured within the framework of a punching and milling operation. All of the working portions of the anchor 1, the nose member 15, the entrainment opening 13, the shoulders 8, the limit,

stops 6 and the pivot recess are thereupon simultaneously trued (subsequently punched). As a result, the anchor body or member 1 for example can be formed from a light metal or alloy plate, such as anticordal. In order to impart to the working surfaces of the anchor body 1 a hardness and durability which is substantially wear resistant it is possible to expose the anchor to an appropriate treatment. To this end, in the, first instance reference is made to an anodic oxidation process (eloxation process) which does not in any way change the dimensions of the parts of the anchor.

Due to the fact that all of the working surfaces of the anchor and above all the working surfaces of the limit stops as well as the shoulders and the inner surface of the central bore of the anchor provide peripheral or marginal surface portions of the same piece which are disposed substantially axially parallel to the axis of to tation of the anchor, such can also be conjointly planed in the same working operation. This takes place with the aid of a punch press and a single tool by means of which the necessary precision can be achieved, so that no additional adjustment is necessary.

The herein described anchor can also be manufactured by means of an injection molding process from plastic material. The same holds true for manufacturing by sintering with self-lubricating materials. Finally, the nose member at the forward face of the thin wall, depending upon the conditions of installation of the balance wheel, can also extend up to the height of the upper surface of the anchor body, whereby the horns 19 must extend lower than the nose member 15.

While there is shown and described present preferred embodiment of the invention it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practised within the scope of the following claims.

What is claimed is:

1. Anchor escapement for timepieces comprising an anchor body mounted for oscillatory movement about an axis of rotation, an escape wheel positioned to cooperate with said anchor body, said anchor body including drive shoulder means and limit stop means, said limit stop means cooperating with said escape wheel to limit the amplitude of oscillation of said anchor body, said drive shoulder means and said limit stop means being integral with said anchor body, both said drive shoulder means and said limit stop means possessing working surfaces defined by peripheral surface elements which are arranged substantially axially parallel to said axis of rotation of said anchor body, said escape wheel including a plurality of spaced teeth, each of said teeth having a drive surface, said anchor body incorporating a pair of claw members, each of said claw members including a shoulder bounded by a linear edge portion and defining said limit stop means, said shoulder forming a flat surface portion bearing against a drive surface of a given one of said teeth of said escape wheel at the moment said anchor body is located in one of its terminal oscillatory positions, each claw member further incorporating a shoulder defining said drive shoulder means, said drive shoulder means cooperating with said respective drive surfaces of said teeth of said escape wheel in order to impart oscil- .latory motion to said anchor body, said drive shoulder .means of each claw member possessing a flat surface portion providing a drive surface for said associated drive shoulder means, a lateral surface portion located at said driveshoulder means at a predetermined angle with respect to its associated flat surface portion, said lateral surface portion providing a rest surface for the correspending drive shoulder means, with a tooth of said escape wheel contacting said lateral surface portion of one of said claw members in each one of said terminal oscillatory positions.

2. Anchor escapement for timepieces comprising an anchor body mounted for oscillatory movement about an axis of rotation, an escape wheel positioned to cooperate with said anchor body, said anchor body including drive shoulder means and limit stop means, said limit stop means cooperating with said escape Wheel to limit the amplitude of oscillation of said anchor body, said dri Shou der means and said limit stop m ns ing integral with said anchor body, both said drive shoulder means and said limit stop means possessing working surfaces defined by peripheral surface elements which are arranged substantially axially parallel to said axis of rotation of said anchor body, a support member serving as guide means for the oscillatory movement of said anchor body, said support member having a pair of spaced, symmetrically disposed support arms between which there is provided a recess, a pin stub carried by said support member and projecting out of the latter to one side, said anchor body being provided with a bore, said pin stub engaging with said bore.

3. Anchor escapement for timepieces as defined in claim 1 including a support member serving as guide means for the oscillatory movement of said anchor body, said support member having a pair of spaced, symmetrically disposed support arms between which there is provided a recess, a pin stub carried by said support member and projecting out of the latter to one side, said anchor body being provided with a bore, said pin stub engaging with said bore.

4. Anchor escapement for timepieces as defined in claim 3 further including a plate, fastening means for connecting said support member with said plate.

5. Anchor escapement for timepieces as defined in claim 4 wherein a further plate is connected to one side of said anchor body by said fastening means.

6. Anchor escapement for timepieces as defined in claim 5 wherein said support member is provided with a substantially ring-shaped rib concentrically arranged with respect to said pin stub, said anchor body bearing via its anchor rod against said ring-shaped rib, said anchor body being located with a certain play between said ring-shaped rib and said further plate.

7. Anchor escapement for timepieces as defined in claim 6, further including bolt means carried by said plate, said pin stub and said bolt means being positioned so as to insure for the arrangement and orientation of said support member with resnect to said plate.

8. Anchor escapement for timepieces comprising an anchor body mounted for oscillatory movement about an axis of rotation, an escape wheel positioned to cooperate with said anchor body, said anchor body including drive shoulder means and limit stop means, said limit stop means cooperating with said escape wheel to limit the amplitude of oscillation of said anchor body, said drive shoulder means and said limit stop means being integral with said anchor body, both said drive shoulder means and said limit stop means possessing working surfaces defined by peripheral surface elements which are arranged substantially axially parallel to said axis of rotation of said anchor body, said anchor body further including a relatively thin wall, a nose member provided at said relatively thin wall, said relatively thin wall being aligned with a surface of said anchor body, said anchor body additionally including a pair of horn members between which said relatively thin wall extends, each side of said thin wall being integrally connected with the associated horn member, said anchor body having an anchor rod provided with a widened terminal piece at the end thereof remote from said drive shoulder means and limit stop means, said widened terminal piece having an opening, an entrainment member entering said opening, said widened terminal piece including a face portion, a projection constructed to define said nose member located atthe highest point of said face portion, said widened terminal piece being provided at its upper end with a circular-shaped edge formed such that said relatively thin wall only remains above said opening which merges with a surface of said anchor body, said pair of spaced horn members being arranged substantially symmetrical to the lengthwise aXis of said anchor rod, said pair of horn members being disposed between said opening and said face portion of said widened terminal piece.

9. Anchor escapement for timepieces, comprising an anchor body mounted for oscillatory movement about an axis of rotation, an escape wheel positioned to cooperate with said anchor body, said escape wheel comprising a plurality of teeth each having a flat drive surface and a linear edge portion extending at the forward end of said drive surface substantially parallel to the axis of the escape wheel, said anchor body comprising a pair of drive shoulder means and limit stop means, said drive shoulder means each comprising a flat drive surface and a stop surface, said teeth and drive shoulder means being arranged in such a manner that each tilting movement imparted to the anchor body is provided by the flat drive surface of one of said teeth and one of said drive shoulder means acting successively, said limit stop means each comprising a plane surface portion arranged to abut when the anchor body is in a given one of its terminal positions, the flat drive surface of that tooth wherein the linear edge thereof engages with the corresponding stop surface of the anchor body thus limiting the amplitude of oscillation of said anchor body, said limit stop means and drive shoulder means being integral With said anchor body.

10. Anchor escapement according to claim 9, wherein said anchor body is formed of a substantially plane plate member, said limit stop means each extending on the same side of a corresponding one of said drive shoulder means, said plate member being provided along its periphery with a pair of recesses, each of said recesses being located between one of said limit stop means and the corresponding one of said drive shoulder means.

References Cited UNITED STATES PATENTS 256,708 4/1882 Lane 58-421 348,980 9/1886 Lane 58-121 RICHARD B. WILKINSON, Primary Examiner.

GERALD F. BAKER, Examiner. MICHAEL L. LORCH, Assistant Examiner,

Claims

1. ANCHOR ESCAPEMENT FOR TIMEPIECES COMPRISING AN ANCHOR BODY MOUNTED FOR OSCILLATORY MOVEMENT ABOUT AN AXIS OF ROTATION, AN ESCAPE WHEEL POSITIONED TO COOPERATE WITH SAID ANCHOR BODY, SAID ANCHOR BODY INCLUDING DRIVE SHOULDER MEANS AND LIMIT STOP MEANS, SAID LIMIT STOP MEANS COOPERATING WITH SAID ESCAPE WHEEL TO LIMIT THE AMPLITUDE OF OSCILLATION OF SAID ANCHOR BODY, SAID DRIVE SHOULDER MEANS AND SAID LIMIT STOP MEANS BEING INTEGRAL WITH SAID ANCHOR BODY, BOTH SAID DRIVE SHOULDER MEANS AND SAID LIMIT STOP MEANS POSSESSING WORKING SURFACES DEFINED BY PERIPHERAL SURFACE ELEMENTS WHICH ARE ARRANGED SUBSTANTIALLY AXIALLY PARALLEL TO SAID AXIS OF ROTATION OF SAID ANCHOR BODY, SAID ESCAPE WHEEL INCLUDING A PLURALITY OF SPACED TEETH, EACH OF SAID TEETH HAVING A DRIVE SURFACE, SAID ANCHOR BODY INCORPORATING A PAIR OF CLAW MEMBERS, EACH OF SAID CLAW MEMBERS INCLUDING A SHOULDER BOUNDED BY A LINEAR EDGE PORTION AND DEFINING SAID LIMIT STOP MEANS, SAID SHOULDER FORMING A FLAT SURFACE PORTION BEARING AGAINST A DRIVE SURFACE OF A GIVEN ONE OF SAID