Patent Description:
Timepieces including a crown have been available. In such a timepiece, the crown is connected to a movement via a stem. Rotary power generated by rotation of the crown is transmitted to the movement to wind a mainspring of the movement, driving the timepiece. The crown of such a timepiece can be pulled out, and is rotated in a pulled state by a user of the timepiece to perform, for example, an operation for setting the time.

To prevent an operation that a user does not intend from being performed, some of such timepieces lock the crown into an outer case with a screw structure to restrict pulling out the crown. However, a user needs to unlock and then rotate the crown every time the mainspring is wound, and may find it troublesome. Patent Literature <NUM> describes a timepiece that can wind a mainspring by rotating a crown even when the crown is locked by a screw structure.

The <CIT> discloses a device for orientating a threaded watch crown. A ring is designed to adjust the position of knurled screw knob of a watch with respect to the watch casing, whilst retaining the sealing qualities of the watch. The knob can take up a disengaged screw position and an engaged screw position with respect to a knob support tube fixed to the casing. The ring is made from a shape memory Micro-Niti alloy. The ring is placed between the casing and tube supporting the knob.

The <CIT> discloses a watch winder with a crown screwed onto the case and having within an axial tube a device for coupling with the winder stem, arranged and shaped so that said crown can perform, when unscrewed, the functions of reassembly and time setting; wherein said axial tube is permanently fixed to the crown and has, at its end opposite the crown, a part projecting inwards and constituting one of the elements of the coupling, the other elements of the coupling being introduced into said tube before its fixing to the crown.

The <CIT> discloses a crown and fixed tube assembly for a watch. The assembly has a connection unit for connecting a rotary crown on an end of a fixed tube. The connection unit is constituted by an elongated housing formed on an inner periphery of the crown for forming a ramp along a determined inclination angle. The ramp has an end forming a stop, and an open zone emerging on an outer lower surface of the crown for permitting the introduction, rotation and axial displacement of a perpendicular pin for forming a bayonet assembly during the mounting of the crown on the tube. The pin is formed at the end of the tube.

However, the timepiece described in Patent Literature <NUM> includes a guard part for locking the crown and an operation part for rotating the crown, and the operation part is provided closer to an outer case than the guard part, separately from the head of the crown. This increases the number of components, imposing constraints of design on the timepiece described in Patent Literature <NUM>.

A timepiece according to an embodiment enables a crown to be rotated even when it is locked, using a structure that does not cause constraints of design.

The timepiece according to an embodiment includes an outer case having a movement therein, the outer case having a crown hole through a portion thereof; an engagement member connected to the outer case; and a crown. The crown includes a shaft part inserted into the crown hole and connected to the movement; an operation part holding the shaft part movably along an axial direction of the shaft part and enabling the shaft part to rotate in a circumferential direction; and an engagement part disposed between the engagement member and the operation part and restricting movement of the operation part in the axial direction when engaged with the engagement member, the engagement part holding the operation part rotatable relative to the engagement part whether or not engaged with the engagement member.

The engagement member in the timepiece according to an embodiment is preferably formed integrally with the outer case.

The engagement member in the timepiece according to an embodiment is preferably formed separately from the outer case.

The engagement part in the timepiece according to an embodiment preferably engages with the engagement member by screwing.

The engagement part in the timepiece according to an embodiment preferably holds the operation part rotatable relative to the engagement part with a fastening structure formed between an inner circumference of the engagement part and the operation part.

The engagement part in the timepiece according to an embodiment preferably holds the operation part rotatable relative to the engagement part with a barbed structure formed between an outer circumference of the engagement part and the operation part.

The crown in the timepiece according to an embodiment is preferably configured to be capable of winding a mainspring of the movement by rotation when the engagement part is engaged with the engagement member, and configured to be capable of rotating, by rotation, a hand connected to the movement when engagement between the engagement part and the engagement member is released and the crown is pulled out.

The timepiece according to an embodiment enables a crown to be rotated even when it is locked, using a structure that does not cause constraints of design.

The objects and advantageous effects of the present invention will be understood and achieved by means of components and combinations thereof mentioned, in particular, in the claims. Both the foregoing general and the following detailed descriptions are illustrative and explanatory ones, and do not limit the invention described in the claims.

Hereinafter, various embodiments of the present invention will be described with reference to the drawings. However, note that the technical scope of the present invention is not limited to these embodiments and includes the invention described in the claims and equivalents thereof.

<FIG> is a front view of a movement <NUM> of a timepiece according to an embodiment, and <FIG> is a schematic diagram for briefly describing the movement <NUM>. <FIG> schematically shows the relationship between components of the movement <NUM>. In <FIG>, the teeth of gears of the components are omitted from illustration.

First, operation in a state in which a crown is not pulled out (hereafter, a "first state") will be described with reference to <FIG> and <FIG>.

A stem <NUM> is a shaft-like member screwed to a crown, and rotates in the circumferential direction together with rotation of the crown. To the stem <NUM>, a clutch wheel <NUM> is fitted slidably in the axial direction of the stem <NUM>, and a winding pinion <NUM> is fitted rotatably in the circumferential direction of the stem <NUM>. In the first state, when the stem <NUM> rotates together with rotation of the crown, the clutch wheel <NUM> rotates and the winding pinion <NUM>, which meshes with the clutch wheel <NUM>, rotates. Rotation of the winding pinion <NUM> is transmitted to a crown wheel <NUM>, a ratchet wheel <NUM>, and a barrel arbor <NUM> in this order, and a mainspring connected to the barrel arbor <NUM> is wound. In this way, the crown is configured to be capable of winding, by rotation, a mainspring connected to the barrel arbor <NUM> of the movement <NUM>. This enables a first operation on the movement <NUM> for winding the mainspring.

Restoring force of the wound mainspring is transmitted to a barrel wheel <NUM>, a center pinion <NUM>, a center wheel <NUM>, a third pinion <NUM>, a third wheel <NUM>, a fourth pinion <NUM>, a fourth wheel <NUM>, an escape pinion <NUM>, and an escape wheel <NUM> in this order to cause a balance <NUM> to periodically oscillate. The center pinion <NUM> and the center wheel <NUM>, the third pinion <NUM> and the third wheel <NUM>, the fourth pinion <NUM> and the fourth wheel <NUM>, and the escape pinion <NUM> and the escape wheel <NUM> are components of a center wheel and pinion <NUM>, a third wheel and pinion <NUM>, a fourth wheel and pinion <NUM>, and an escape wheel and pinion <NUM>, respectively. In order for the escape wheel <NUM> to oscillate the balance <NUM>, an escapement, such as an anchor escapement, is used.

To the center wheel and pinion <NUM>, a minute hand <NUM> is attached. The center wheel and pinion <NUM> is configured to make one revolution in <NUM> minutes. The fourth wheel and pinion <NUM> is configured to transmit this rotation to a second hand <NUM> (see <FIG>) and to make one revolution in <NUM> seconds. Rotation of the center wheel and pinion <NUM> is transmitted from a cannon pinion (not shown), which operates together with the center wheel <NUM>, via a minute wheel and pinion <NUM> to an hour wheel <NUM>. To the hour wheel <NUM>, an hour hand <NUM> is attached. The hour wheel <NUM> is configured to make one revolution in <NUM> hours.

Next, operation in a state in which the crown is pulled out (hereafter, a "second state") will be described.

In the second state, the clutch wheel <NUM> does not mesh with the winding pinion <NUM> but with a setting wheel <NUM>. In the second state, when the stem <NUM> rotates together with rotation of the crown, rotation of the stem <NUM> is transmitted to the clutch wheel <NUM>, the setting wheel <NUM>, an intermediate setting wheel <NUM>, and a minute wheel <NUM> in this order to rotate the hour wheel <NUM>, to which the hour hand <NUM> is attached, and the cannon pinion. Rotation of the cannon pinion rotates the center wheel and pinion <NUM>, to which the minute hand <NUM> is attached. In this way, the crown is configured to be capable of rotating, by rotation, the hour hand <NUM> and the minute hand <NUM> connected to the movement <NUM>. This enables a second operation on the movement <NUM> for setting the time. The hour hand <NUM> and the minute hand <NUM> are examples of the hand.

<FIG> are schematic diagrams for explaining operation depending on the position of the pull-out crown. <FIG> is a schematic diagram of the first state. In the first state, the clutch wheel <NUM> receives elastic force of a yoke spring <NUM> via a yoke <NUM> to be pushed toward the winding pinion <NUM>, meshing with the winding pinion <NUM>. In the first state, rotary power of the stem <NUM> is transmitted to the winding pinion <NUM>.

<FIG> is a schematic diagram of the second state. In the second state, a head <NUM> of a setting lever <NUM> inserted into a groove <NUM> of the stem <NUM> is pulled out together with the stem <NUM>, and a bottom <NUM> of the setting lever <NUM> pushes the yoke <NUM> toward the setting wheel <NUM>. In the second state, the clutch wheel <NUM> meshes with the setting wheel <NUM>, causing rotary power of the stem <NUM> to be transmitted to the setting wheel <NUM>.

Note that the above brief description of the movement <NUM> is for explaining operation of the crown, and that another movement different from the movement <NUM> may be used for the timepiece according to the embodiment.

<FIG> is a top view of a timepiece <NUM> according to the first embodiment, and <FIG> shows a portion of a cross section taken along line I-I in <FIG>. In <FIG>, the hour hand <NUM>, the minute hand <NUM>, and the second hand <NUM> are omitted from illustration. The timepiece <NUM> includes an outer case <NUM>, a crown <NUM>, a bezel <NUM> and <NUM>, and a protective glass <NUM>. Below the protective glass <NUM>, a dial <NUM>, a first dial ring <NUM>, a second dial ring <NUM>, and a rotating shaft <NUM> are provided. The hour hand <NUM>, the minute hand <NUM>, and the second hand <NUM> are set to the rotating shaft <NUM> and rotates together with the hour wheel <NUM>, the center wheel and pinion <NUM>, and the fourth wheel and pinion <NUM>, respectively. The first dial ring <NUM> and the second dial ring <NUM> are annular members covering the periphery of the dial <NUM>. Below the dial <NUM> is incorporated the movement <NUM> connected to the rotating shaft <NUM> to drive the hands, i.e., the hour hand <NUM>, the minute hand <NUM>, and the second hand <NUM> (regarding the components of the movement <NUM>, see <FIG> and <FIG>). On the underside of the timepiece <NUM>, a case back <NUM> and a case back holder <NUM> are provided. The side surface of the outer case <NUM> has a crown hole <NUM> through a portion thereof. Into the crown hole <NUM>, a cylindrical pipe <NUM> is inserted and attached by fixing. The pipe <NUM> is an example of the engagement member. In the example shown in <FIG>, the pipe <NUM> is formed separately from the outer case <NUM>. As shown in <FIG>, the pipe <NUM> may be formed integrally with the outer case <NUM>. For example, the pipe <NUM> may be formed together with the outer case <NUM> by injection molding. The following description will be given by assuming that the pipe <NUM> is formed separately from the outer case <NUM>.

The crown <NUM> enables operation on the movement <NUM>. For example, the crown <NUM> transmits rotary power to the movement <NUM>. To achieve this, the crown <NUM> includes a shaft part <NUM>, an operation part <NUM>, and an engagement part <NUM>. The shaft part <NUM> is inserted into the pipe <NUM>. The shaft part <NUM> has one end connected to the movement <NUM> via the stem <NUM>, and transmits rotary power. The operation part <NUM> is provided at the other end of the shaft part <NUM> and operated to enable the shaft part <NUM> to move in the axial direction and rotate in the circumferential direction. The engagement part <NUM> is a cylindrical member disposed between the operation part <NUM> and the pipe <NUM>. The engagement part <NUM> restricts movement of the operation part <NUM> in the axial direction when engaged with the pipe <NUM>, and rotatably holds the operation part <NUM> whether or not engaged with the pipe <NUM>. In the following, the state in which the engagement part <NUM> is engaged with the pipe <NUM> and thereby restricts movement of the operation part <NUM> in the axial direction will be referred to as a "locked state.

<FIG> are enlarged views of the crown <NUM> and its vicinity in a cross section of the timepiece <NUM>. The following describes details of the structure of the crown <NUM>, using <FIG>.

<FIG> is a cross-sectional view in the locked state. As shown in <FIG>, the shaft part <NUM> is inserted into the pipe <NUM>, which is inserted into the crown hole <NUM> formed in the outer case <NUM>. The outer circumference of the shaft part <NUM> and the inner circumference of the pipe <NUM> are both circular, and the shaft part <NUM> is rotatable in the circumferential direction when inserted into the pipe <NUM>. The end of the shaft part <NUM> has a recess <NUM> into which the stem <NUM> is inserted. The stem <NUM> is fixed to the recess <NUM>, for example, by screwing and thereby connected to the shaft part <NUM>. The stem <NUM> may be formed integrally with the shaft part <NUM>. Around the shaft part <NUM>, a waterproofing member <NUM>, such as a gasket, may be provided.

The operation part <NUM> includes a head <NUM> and an inner cylinder <NUM>. The head <NUM> is fixed to the inner cylinder <NUM>, into which part of the shaft part <NUM> is inserted. The inner circumference of the inner cylinder <NUM> and the outer circumference of a flange <NUM> of the shaft part <NUM> each have a square shape of substantially the same diameter, and the inner cylinder <NUM> and the shaft part <NUM> rotate in the circumferential direction together. More specifically, rotation of the head <NUM> rotates the inner cylinder <NUM> fixed to the head <NUM> and rotates the shaft part <NUM> together. In this way, the operation part <NUM> enables the shaft part <NUM> to rotate in the circumferential direction.

The engagement part <NUM> includes a body <NUM> and a holder <NUM>. The body <NUM> fixed to the holder <NUM> is coupled to a flange <NUM> of the inner cylinder <NUM> to form a fastening structure <NUM> between the inner circumference of the engagement part <NUM> and the operation part <NUM>. More specifically, the holder <NUM> is fixed to the inner circumference of the body <NUM>, and thereby the engagement part <NUM> has a portion whose inner circumference has a larger diameter. The fastening structure <NUM> is formed by coupling to this larger-diameter portion the flange <NUM>, whose outer circumference has a larger diameter in the inner cylinder <NUM>. With the fastening structure <NUM>, the engagement part <NUM> holds the operation part <NUM> so that it is rotatable relative to the engagement part <NUM>. Further, the body <NUM> and the holder <NUM> are not fixed to the inner cylinder <NUM>, and are rotatable relative to the inner cylinder <NUM>. This makes the engagement part <NUM> operate together with the operation part <NUM> in the axial direction of the shaft part <NUM> and hold it rotatably in the circumferential direction. Additionally, an internal thread structure <NUM> provided on the inner circumference of the body <NUM> is screwed to an external thread structure <NUM> of the pipe <NUM>. This makes the engagement part <NUM> restrict movement of the operation part <NUM> in the axial direction when engaged with the pipe <NUM>. Instead of the external thread structure <NUM> and the internal thread structure <NUM>, any structure that enables engagement may be used. Additionally, waterproofing members <NUM> and <NUM>, such as gaskets, may be provided between the body <NUM> and the inner cylinder <NUM> and between the body <NUM> and the head <NUM>, respectively.

In the locked state, the shaft part <NUM> is at a first position where it is not pulled out, as shown in <FIG>. In the locked state also, the operation part <NUM> is rotatably held by the engagement part <NUM>. Thus the crown <NUM> is configured to be capable of winding, by rotation, the mainspring connected to the barrel arbor <NUM> of the movement <NUM> in the locked state. The mainspring can be wound by a user of the timepiece <NUM> rotating the operation part <NUM>.

<FIG> is a cross-sectional view in the first state. Rotating the engagement part <NUM> in the locked state shown in <FIG> releases screwing between the internal thread structure <NUM> of the engagement part <NUM> and the external thread structure <NUM> of the pipe <NUM>, resulting in the first state shown in <FIG>. In the first state, the engagement part <NUM> operates together with the operation part <NUM> in the axial direction. Release of screwing moves the operation part <NUM> and the engagement part <NUM> in the direction away from the pipe <NUM>, but elastic force of a spring <NUM> embedded in the shaft part <NUM> keeps the shaft part <NUM> in the first position where it is not pulled out, as in the locked state. In other words, the position of the shaft part <NUM> relative to the pipe <NUM> does not change from that in the locked state.

In the first state, a user of the timepiece <NUM> can wind the mainspring by rotating the operation part <NUM>. Since the engagement part <NUM> operates together with the operation part <NUM> in the axial direction, the user of the timepiece <NUM> can pull out the operation part <NUM> and the engagement part <NUM>.

<FIG> is a cross-sectional view in the second state. When the operation part <NUM> and the engagement part <NUM> are pulled out in the first state, the shaft part <NUM> is pulled out by the flange <NUM> of the shaft part <NUM> being caught by the inner circumference <NUM> of the inner cylinder <NUM>. Then, the position of the shaft part <NUM> relative to the pipe <NUM> changes in the direction away from the outer case <NUM>. In other words, the shaft part <NUM> moves to a second position where it is pulled out. This results in the second state and enables the second operation for setting the time.

As described above, the engagement part <NUM> of the timepiece <NUM> is disposed between the pipe <NUM> and the operation part <NUM> and engaged with the pipe <NUM> to restrict movement of the operation part <NUM> in the axial direction of the shaft part <NUM>, and rotatably holds the operation part <NUM> whether or not engaged with the pipe <NUM>. Thus the timepiece <NUM> enables the crown <NUM> to be rotated even when it is in the locked state. Additionally, the engagement part <NUM> disposed between the pipe <NUM> and the operation part <NUM> eliminates the need for including another member outside the crown <NUM>, and does not cause constraints of design.

A timepiece according to a second embodiment differs from the timepiece <NUM> according to the first embodiment in the structure of the operation part <NUM> and the engagement part <NUM> of the crown <NUM>. The following describes a crown 3a of the timepiece according to the second embodiment, using <FIG>.

<FIG> is a cross-sectional view of the crown 3a of the timepiece according to the second embodiment and its vicinity. The crown 3a according to the second embodiment includes a shaft part <NUM>, an operation part <NUM>, and an engagement part <NUM>. The cross section shown in <FIG> is taken along the same line as the cross sections shown in <FIG>, but in <FIG>, the outer case <NUM>, the stem <NUM>, the case back holder <NUM>, and the second dial ring <NUM>, which are shown in <FIG>, are omitted from illustration. The same reference numerals are assigned to components similar to those in the first embodiment, and explanation thereof will be omitted as appropriate.

The operation part <NUM> includes a head <NUM> and an inner cylinder <NUM>. The shaft part <NUM> is inserted into a recess <NUM> of the head <NUM>. The inner circumference of the recess <NUM> and the outer circumference of the flange <NUM> of the shaft part <NUM> each have a square shape of substantially the same diameter, and the head <NUM> and the shaft part <NUM> are configured to rotate in the circumferential direction together. The head <NUM> has a skirt structure <NUM> extending from its outer circumference toward the outer case. The inner cylinder <NUM> is a cylindrical member into which the shaft part <NUM> is inserted, and is fixed to the head <NUM>.

The engagement part <NUM> is a cylindrical member into which part of the operation part <NUM> is inserted, and has an internal thread structure <NUM> on its inner circumference. The engagement part <NUM> has such a shape as to fit in the skirt structure <NUM> of the operation part <NUM>. The internal thread structure <NUM> is a structure that can be screwed to the external thread structure <NUM> of the pipe <NUM>. Between the engagement part <NUM> and the inner cylinder <NUM>, a waterproofing member <NUM>, such as a gasket, may be provided.

Claim 1:
A timepiece (<NUM>) comprising:
an outer case (<NUM>) having a movement therein, the outer case (<NUM>) having a crown hole (<NUM>) through a portion thereof;
an engagement member (<NUM>) connected to the outer case (<NUM>); and
a crown (<NUM>, 3a),
wherein the crown (<NUM>, 3a) comprises:
a shaft part (<NUM>) inserted into the crown hole (<NUM>) and connected to the movement;
an operation part (<NUM>, <NUM>) holding the shaft part (<NUM>) movably along an axial direction of the shaft part (<NUM>) and enabling the shaft part (<NUM>) to rotate in a circumferential direction; and
an engagement part (<NUM>, <NUM>) disposed between the engagement member (<NUM>) and the operation part (<NUM>, <NUM>) and restricting movement of the operation part (<NUM>, <NUM>) in the axial direction when engaged with the engagement member (<NUM>),
characterized in that the engagement part (<NUM>, <NUM>) holds the operation part (<NUM>, <NUM>) rotatable relative to the engagement part (<NUM>, <NUM>) whether or not the engagement part (<NUM>, <NUM>) is engaged with the engagement member (<NUM>).