JP2014160001A - Hair spring, movement, clock, and method for manufacturing hair spring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a large bent portion in an outer end curve region R of a hair spring 1 used for the balance 19 of a clock 15 and reduce thickness.SOLUTION: A hair spring 1 is wound to be cup-shaped while a linear spring material 2 expands a diameter upward and outward from the inside. Thereby, eccentricity following expansion and contraction of the hair spring 1 is reduced, and the same rate accuracy and isochrony as a Breguet hair spring 103 are obtained. A large bent portion in a surface direction and vertical direction of a spiral in an outer end curve region R of the hair spring 1 is eliminated to reduce temporal deformation.

Description

  The present invention relates to a hairspring used for a balance of a mechanical timepiece, a movement including a hairspring, a timepiece including a hairspring, and a method for manufacturing the hairspring.

  Conventionally, a balance spring in which a belt-like spring made of an elastic body is wound in a spiral shape is used for a balance of a mechanical timepiece. For example, Patent Document 1 describes a mechanical timepiece. In the mechanical timepiece, the barrel is rotated by the power of the mainspring, and the rotation of the barrel is transmitted from the second gear to the wheel train constituted by the fourth gear and the like. The rotational speed of the train wheel is regulated by an escapement unit composed of a balance with balance, ankle and escape wheel, and is configured to keep time at a constant rate.

  FIG. 10 is a schematic diagram of the balance with hairspring 110. The balance with hairspring 110 includes a hairspring 100, a hairball 113 connected to the inner end of the hairspring 100, a beard 114 connected to the outer end of the hairspring 100, and a balance stem 112 serving as the axial center of the hairspring 113. A balance wheel 111 is connected to the balance stem 112 and performs reciprocating rotational vibration with the balance stem 112 as a rotation axis. The rate accuracy of the mechanical timepiece is determined by the vibration period of this reciprocating rotational vibration. The vibration cycle of the balance wheel 111 is determined by the rotational biasing force of the balance spring 100 that biases the rotation of the balance stem 112 and the rotational moment of the balance wheel 111. The hairspring 100 needs to be formed so that the rotational urging force is not affected by a temperature change or a posture difference. The hairspring 100 expands and contracts with the rotation of the spring 112, but it is desirable to form the spiral so as to concentrically expand and contract so that the center of gravity of the spiral is always at the position of the axis of the rotation shaft.

  FIG. 11 is a schematic diagram of a hairspring 100 generally used in a mechanical timepiece. 11 (a), (b), and (c) are explanatory diagrams of the flat hairspring 101, the Breguet hairspring 103, and the lantern hairspring 105, respectively, and the upper diagram is a schematic diagram viewed from above the spiral. The following figure is a schematic view seen from the lateral direction of the spiral.

  As shown in FIG. 11 (a), the flat hair spring 101 is made of a thin band of copper or an Elinvar alloy, and has a spiral shape wound in one plane. An outer end curve 102 is formed on the outer periphery of the spiral, and is bent outward from the pitch distance in the radial direction of the spiral. A whisker for fixing the flat hairspring 101 is installed on the outer end curve 102 so that the inner hairspring and the whisker are not in contact with each other.

  As shown in FIG. 11B, the Breguet hairspring 103 is formed by winding the outer end curve 102 inwardly and upwardly from the outer periphery of the hairspring 100. Since the outer end curve 102 is wound upward, it does not come into contact with the hairspring 100 even if a whisker is installed. The outer end curve 102 of the Breguet hairspring 103 is bent inside the spiral so as to satisfy the Phillips condition, and is formed so that the center of rotation does not decenter when the hairspring 100 is expanded or contracted.

  As shown in FIG. 11C, the lantern balance spring 105 has a lantern shape as a whole, and the balance spring expands and contracts on a concentric circle as the balance wheel rotates. For this reason, it is used for high-accuracy watches with high accuracy.

JP 2006-214822 A

  In the flat hairspring 101 shown in FIG. 11A, the outermost hairspring 100 is largely bent to form the outer end curve 102. However, the greatly bent portion is easily deformed with time. Further, in the Breguet hairspring 103 shown in FIG. 11B, the outer end curve 102 of the hairspring 100 is wound up inside the spiral so as to satisfy the Philips condition. Therefore, it is necessary to bend the hairspring 100 with a large stress above the spiral, and it is difficult to form the outer end curve 102. Moreover, it is easy to deform over time due to residual stress. When the outer end curve 102 of the hairspring 100 is deformed with time, the vibration period is changed to reduce the accuracy of the rate, or the isochronism of the vibration period is changed according to the magnitude of the rotation touch angle. Further, the lantern balance spring 105 shown in FIG. 11C is not suitable for a small timepiece such as a wristwatch because the thickness in the vertical direction is increased.

  The present invention has been made in view of the above problems, and provides a small and highly accurate hairspring and a method for manufacturing the same.

  The hairspring of the present invention has a cup shape in which a linear spring material is wound while expanding the diameter from the inside to the outside and upward.

  In addition, the first spring and the second roll of the spring material, as counted from the outer end, intersect with each other in a plan view when the cup shape is viewed from above. The spring material and the second roll of spring material were separated from each other.

  Further, a whisker ball connected to an inner end of the spring material, the whisker ball includes a fitting groove into which the spring material is fitted, and the fitting groove is perpendicular to the cup-shaped vertical direction. It was decided to incline.

  Further, the cup shape has a U-shaped vertical cross-sectional shape.

  The movement of the present invention is provided with any of the hairsprings described above.

  The timepiece of the present invention includes any one of the above-described hairsprings.

  The method of manufacturing a hairspring of the present invention includes a flat hairspring forming step of forming a flat flat spring on which a spring material is wound, a deformation step of deforming the flat hairspring into a cup shape, and the flat hairspring A heat treatment step of heat-treating the mainspring and brazing it into the cup shape.

  Further, the deformation step is a step of pressing the convex mold relative to the concave mold with the flat spring between the convex mold and the concave mold, and removing the convex mold and the concave mold after the heat treatment process. Thus, a removal process for taking out the cup-shaped hairspring is provided.

  Further, the deformation step is a step of sandwiching the flat hair spring between the convex mold and a plurality of pressing pins with the upper ends aligned, and relatively pressing the convex mold against the plurality of pressing pins, After the heat treatment step, the convex shape and the plurality of pressing pins are removed, and an extraction step of taking out the cup-shaped hairspring is provided.

  Further, the deformation step is a step in which the pressing pin is inserted between the wound spring materials.

  The hairspring of the present invention has a cup shape in which a linear spring material is wound while expanding from the inside to the outside and upward. Thereby, the eccentricity accompanying the expansion and contraction of the hairspring is reduced, and the rate accuracy and isochronism equivalent to the Breguet hairspring are ensured. In addition, a large bent portion is eliminated in the surface direction of the spiral or in the vertical direction of the spiral in the outer end curve region of the hairspring to reduce deformation with time.

It is explanatory drawing of the hairspring based on 1st embodiment of this invention. It is explanatory drawing of the hairspring based on 1st embodiment of this invention. It is explanatory drawing of the hairspring based on 1st embodiment of this invention. It is a cross-sectional schematic diagram of the hairspring according to the second embodiment of the present invention. It is a side surface schematic diagram of the hairspring which concerns on 3rd embodiment of this invention. It is process drawing of the manufacturing method of the hairspring based on 4th embodiment of this invention. It is a cross-sectional schematic diagram for demonstrating each process of the manufacturing method of the hairspring which concerns on 4th embodiment of this invention. It is explanatory drawing of the manufacturing method of the hairspring based on 5th embodiment of this invention. It is a schematic diagram of the timepiece according to the sixth embodiment of the present invention. It is a schematic diagram of the balance of a timepiece conventionally known. It is a schematic diagram of a hairspring used in a conventionally known general mechanical timepiece.

(First embodiment)
1-3 is explanatory drawing of the hairspring 1 which concerns on 1st embodiment of this invention. FIG. 1 is a schematic perspective view of the hairspring 1, FIG. 2 is a schematic plan view seen from above the cup shape of the hairspring 1, and FIG. 3 is a schematic side view seen from the side of the cup shape.

  As shown in FIG. 1, the hairspring 1 has a cup shape in which a linear spring material 2 is wound while expanding in diameter from the inside toward the outside and upward. More specifically, the spring material 2 is composed of a wide band in the vertical direction of a cup shape (that is, a spiral), and the band of the spring material 2 is wound in a divergent shape from the inside to the outside and upward. As shown in FIG. 2, the spring material 2 has an outer end E2 bent to the inside of the spiral, and intersects with the lower spring material in a plan view as viewed from above the spiral (upper cup shape). Here, at the intersection K where the first spring material 21 and the second spring material 22 intersect from the outer end E2, the first spring material 21 and the second spring material 22 Are separated. That is, the lower end of the first roll spring material 21 and the upper end of the second roll spring material 22 are separated from each other.

  This will be specifically described with reference to FIG. The hairspring 1 has a cup shape, and the vertical cross-sectional shape of the cup shape has a V shape. FIG. 3 shows a member connected to the hairspring 1. First, the whisker ball 3 is connected to the inner end E1 which is the bottom of the cup shape. The whiskers 4 are connected to the outer end E2 which is the upper part of the cup shape. The balance wheel 6 is locked to the upper part of the balance 5. The whisker 4 is fixed to, for example, a watch movement. The balance stem 5 serves as a rotational axis of the reciprocating rotational vibration between the balance wheel 6 and the hairspring 1. The reciprocating rotational vibration of the balance wheel 6 is transmitted to the hairspring 1 through the balance 5 and the hairball 3, and the hairspring 1 repeats expansion and contraction. The balance wheel 6 may be locked to the balance 5 at the lower part of the hairspring 1.

  Thus, when the hairspring 1 is cup-shaped, the thickness in the vertical direction can be made thinner than that of the lantern spring. Therefore, it can be used for a small timepiece such as a wristwatch. Further, at the intersection K, there is a gap between the first roll spring material 21 and the second roll spring material 22. Therefore, the expansion / contraction motion of the second-roll spring material 22 is not hindered by the first-roll spring material 21. That is, since the spring members 2 are not in contact with each other at the intersection K, it is possible to prevent the center of gravity from moving from the rotation axis of the balance spring 1 (the axis of the spring 5) and changing the vibration cycle.

  A region where the spring material 2 is bent inward from the vicinity of the intersection K to the outer end E2 is defined as an outer end curve region R. In the outer end curve region R, the spring material 2 is smoothly bent inside the spiral. The outer end E2 of the spring material 2 is brought closer to the center axis side of the spiral (the balance 5 side in FIG. 3), and a space is secured below the outer end E2. Therefore, the beard 4 can be attached to the outer end E2 of the spring material 2 without lifting the end of the spring material upward (in the vertical direction of the spiral) like a Breguet hairspring. Moreover, since the outer end curve region R is bent inward, the hairspring 1 can be easily grasped with tweezers or the like.

  In the present embodiment, the spring material 2 in the outer curve region R of the first spring material 21 and the spring material 2 in the other region including the second spring material 22 are in the vertical direction of the spiral (spring The inclination angle is equal to the axial direction of 5). Therefore, even when the spring material 2 composed of a wide band in the vertical direction of the spiral is used, it is not necessary to bend the spring material 2 in the outer end curved region R with a large stress in the wide direction of the band. Becomes easy. Moreover, the residual stress in the outer end curve region R is reduced, and the mainspring 1 with little deformation with time can be formed. Thereby, the hairspring 1 excellent in rate accuracy and isochronism can be formed.

  The spring material 2 can be made of plastic, metal, alloy, or other material. For example, if Elinvar, Terimbar, Nivalox, Coelinbar or the like is used as an alloy, a highly accurate timepiece having a stable vibration cycle with respect to temperature changes and attitude differences can be formed. In addition, the spring material 2 may be formed in a circular shape, an elliptical shape, or a rectangular shape, instead of being formed by a band whose cross-sectional shape is rectangular in the vertical direction of the spiral. It may be. If the band is wide in the vertical direction of the spiral as in this embodiment, the spiral and the outer end curve region R can be easily brazed.

(Second embodiment)
FIG. 4 is a schematic cross-sectional view of the hairspring 1 according to the second embodiment of the present invention. The difference from the first embodiment is a cup-shaped cross-sectional shape, and the other configurations are the same as those of the first embodiment. The same portions or portions having the same function are denoted by the same reference numerals.

  The hairspring 1 has a cup shape in which a linear spring material 2 is wound while increasing in diameter from the inside toward the outside and upward. The cup shape is U-shaped so that the cross-sectional shape in the vertical direction of the spiral is indicated by a one-dot chain line. As in the first embodiment, the spring material 2 is counted from the outer end, and the first and second spring materials 21 and 22 intersect each other in a plan view as viewed from the vertical direction of the spiral. The first spring material 21 and the second spring material 22 are separated from each other at the intersection K where the two intersect. Thereby, the expansion / contraction motion of the second-roll spring material 22 is not hindered by the first-roll spring material 21, and the accuracy and isochronism of the period in the reciprocating rotational vibration can be ensured.

  Furthermore, since the spring material 2 is smoothly bent inward in the outer end curve region R, a space can be secured below the outer end E2 of the spring material 2, and the outer end E2 is lifted upward. The whiskers 4 can be connected without any problems. That is, it is not necessary to bend the spring material 2 in the outer end curve region R by applying a large stress, it is easy to braze the curve, the residual stress in the outer end curve region R is reduced, and deformation with time is small. The hairspring 1 can be formed.

In the present invention, the cross-sectional shape of the hairspring 1 is not limited to a V-shape or a U-shape, and can be a cross-sectional shape represented by the following mathematical formula. Even if it forms so that the cross-sectional shape of the spring material 2 may satisfy | fill a following formula, the effect of the said this invention is realizable.
(1) Quadratic function, y = ax ² + bx + c
(2) The geometric series, a = x _{n + 1} / x _n
(3) Equality series, a = x _{n + 1} −x _n
(4) Trigonometric function, y = asin (θ) + c, (θ = π / 2n)
In Equation (1), the center position of the cup-shaped spiral is the origin, the height of the spring material 2 is represented by y, and the radial position is represented by x. a, b, and c are constants. In Expressions (2) and (3), the center position of the cup-shaped spiral is the origin, and the radial position and the height position of the _n-th spring material 2 counted from the inside of the spiral are x _n. The position in the radial direction and the position in the height direction of the spring material 2 of the (n + 1) th winding counted from the inside of the spiral is represented by _{xn + 1} . a is a constant. In the equation (4), the center position of the cup-shaped spiral is the origin of the polar coordinates, the radius of the spring material 2 of the n-th winding counted from the inside of the spiral is represented by y, and the angle from the horizontal plane of the spiral is θ Represent. Let a and c be constants.

(Third embodiment)
FIG. 5 is an explanatory diagram of the hairspring 1 according to the third embodiment of the present invention. FIG. 5A is a schematic side view of the hairspring 1, FIG. 5B is a perspective view of the hairball 3, and FIG. 5C is a schematic cross-sectional view of the hairball 3. The difference from the first embodiment is that the hairspring 1 includes a hairball 3 connected to the hairspring 1, and the other configurations are the same as those of the first embodiment. The same portions or portions having the same function are denoted by the same reference numerals.

  The hairspring 1 has a cup shape in which a linear spring material 2 is wound while the diameter is increased from the inside to the outside and upward. In the spring material 2, the first spring material 21 and the second spring material 22, which are counted from the outer end, intersect each other in a plan view as viewed from above the cup shape. The spring material 21 of the eye and the spring material 22 of the second roll are separated from each other. The hairspring 1 includes a whisker ball connected to the inner end E1 of the spring material 2. The whisker ball 3 includes a fitting groove 7 into which the spring material 2 is fitted. The groove direction of the fitting groove 7 is inclined with respect to the vertical direction of the spiral. More specifically, the side wall S of the fitting groove 7 is inclined with respect to the vertical direction of the spiral.

  This will be specifically described. The whisker ball 3 has a cylindrical shape, and a through hole 8 into which the balance stem 5 is fitted is formed at the center of the cylinder. A fitting groove 7 is formed on the outer surface of the whistle ball 3. The groove direction of the fitting groove 7 (direction of the side wall S of the fitting groove 7) is inclined at the same inclination angle α as that of the spring material 2 in the inner end region H with respect to the vertical direction of the spiral of the spring material 2. Therefore, when connecting the inner end region H of the spring material 2 to the whistle ball 3, it is not necessary to bend the spring material 2 in the direction perpendicular to the spiral (cup shape). In this embodiment, the wide strip-shaped spring material 2 is used in the vertical direction of the spiral, but has the same inclination angle α as the groove direction of the fitting groove 7 of the whistle ball 3 and the longitudinal direction of the spring material 2. Therefore, the spring material 2 and the whisker ball 3 can be connected very easily. Further, since the spiral shape of the spring material 2 is not deformed after the connection, the rate accuracy and isochronism of the vibration period of the reciprocating rotational vibration of the mainspring 1 can be ensured.

  In the present embodiment, the connection between the whistle ball 3 and the spring material 2 is made by forming a fitting groove 7 on the surface of the whistle ball 3 and fitting the inner end region H of the spring material 2 into the fitting groove 7. However, the present invention is not limited to this connection method. A fitting hole may be formed in the whistle ball 3, and the inner end region H of the spring material 2 may be fitted and connected to the fitting hole. In this case, the center axis of the fitting hole may be formed at an inclination angle α with respect to the vertical direction of the spiral.

(Fourth embodiment)
FIG.6 and FIG.7 is explanatory drawing of the manufacturing method of the hairspring 1 which concerns on 4th embodiment of this invention. FIG. 6 is a process diagram of the method for manufacturing the hairspring 1. FIG. 7 is a schematic cross-sectional view for explaining each process. FIG. 7A shows a state in which the flat hairspring 9 is installed between the concave mold 10 and the convex mold 11, and FIG. FIG. 7C is a schematic cross-sectional view of the hairspring 1 brazed in a cup shape, and FIG. 7D shows the outer end curve region R. FIG. 1 is a schematic cross-sectional view of a hairspring 1 that has been cut. The same portions or portions having the same function are denoted by the same reference numerals.

  As shown in FIG. 6, the method for manufacturing the hairspring 1 according to the present embodiment includes a flat hairspring forming step S <b> 1 for forming a flat flat hairspring 9 around which the spring material 2 is wound, and a flat hairspring 9. A deformation step S2 for deforming into a cup shape and a heat treatment step S3 for brazing the flat hairspring 9 into a cup shape are provided. Furthermore, it includes an extraction step S4 for removing the mold to remove the cup-shaped hairspring 1, and an outer end curve forming step S5 for bending the outer end E2 of the spring material 2 to the inside of the spiral. This will be specifically described with reference to FIG.

  First, in the flat-spring mainspring forming step S1, a flat-plate flat-hairspring 9 that is spirally wound is formed. The flat hairspring 9 connects a plurality of spring materials made of a belt to a winding rod, rotates the winding rod to wind the spring material in a spiral shape, and stores it in a barrel. The barrel that houses the spring material is heated to braze the spring material in a spiral shape. FIG. 7 (a) shows the flat hairspring 9 formed in this manner, with a concave shape 10 having a U-shaped cross-sectional shape and an inner surface recessed in a cup shape, and a U-shaped cross-sectional shape and an outer surface having a cup shape. It is sandwiched between the protruding mold 11.

  Next, in the deformation step S2, as shown in FIG. 7B, the convex mold 11 is pressed against the concave mold 10 to deform the flat hairspring 9 into a cup shape. Next, in the heat treatment step S3, the flat hairspring 9 in which both the concave mold 10 and the convex mold 11 are transformed into a cup shape is heat treated. As a result, the flat hairspring 9 is brazed into a cup shape. Next, in the extraction step S4, as shown in FIG. 7 (c), the hairspring 1 brazed in a cup shape is extracted from the concave mold 10 and the convex mold 11. Next, in the outer end curve forming step S5, as shown in FIG. 7D, the outer end E2 of the spring material 2 is smoothly bent inside the spiral. The outer end curve region R does not need to be bent upward in the cup shape. For this reason, the outer end curve region R can be formed very easily even when the spring material 2 wide in the vertical direction of the spiral is used.

  In addition, the cross-sectional shape of the hairspring 1 having the cup shape is not limited to the U shape, and can be formed so as to satisfy the V shape or the expressions (1) to (4). Further, the spring material 2 of the hairspring 1 is not limited to the belt-shaped spring material 2 that is wide in the vertical direction of the spiral, and the cross-sectional shape may be a circle, an ellipse, a quadrangle, or the like.

(Fifth embodiment)
FIG. 8 is an explanatory diagram of a method for manufacturing the hairspring 1 according to the fifth embodiment of the present invention. 8A shows a state in which the flat hairspring 9 is installed between the convex mold 11 and the pressing pin 12, and FIG. 8B shows a state in which the convex mold 11 is pressed against the pressing pin 12 relatively. FIG. 8C is a schematic cross-sectional view of the hairspring 1 brazed in a cup shape, and FIG. 8D is a schematic cross-sectional view of the hairspring 1 in which the outer end curve region R is formed. The manufacturing process of the hairspring 1 of this embodiment is the same as that of 4th embodiment shown in FIG. The same portions or portions having the same function are denoted by the same reference numerals.

  First, in the flat-spring mainspring forming step S1, a flat-plate flat-hairspring 9 that is spirally wound is formed. The method for forming the flat hairspring 9 is the same as in the fourth embodiment. 8A, the flat hairspring 9 formed in this way is shallow between the plurality of pressing pins 12 and the convex mold 11 whose cross-sectional shape is U-shaped and whose outer surface protrudes into a cup shape. Here, the plurality of pressing pins 12 are bundled inside the frame 13 and are bound to the frame 13 with their upper end surfaces aligned. Each pressing pin 12 is constrained to be movable independently in the vertical direction. For the convex mold 11, the frame 13, and the pressing pin 12, a material made of metal or ceramics can be used according to the heat treatment temperature of the spring material 2.

  Next, in the deformation step S2, as shown in FIG. 8 (b), a plurality of push-down molds 11 are pushed by sandwiching the flat hairspring 9 between the bump 11 and the plurality of pressing pins 12 having the upper ends aligned. It presses relatively to the contact pin 12. Accordingly, the flat hairspring 9 is deformed into a protruding cup shape of the convex mold 11, and the pressing pin 12 is inserted between the wound spring material 2. Therefore, for example, even when the strip-shaped spring material 2 wide in the vertical direction of the spiral is deformed, the pressing pin 12 is inserted into the gap between the spring material 2 and the spring material 2, and the spring material 2 falls down in the horizontal direction to form a spiral shape. Can be prevented from collapsing.

  Next, in the heat treatment step S3, the flat hairspring 9 deformed into a cup shape together with the convex mold 11 and the pressing pin 12 is heat treated. As a result, the flat hairspring 9 is brazed into a cup shape. Next, as shown in FIG.8 (c), the convex type | mold 11 and the some pressing pin 12 are removed, and the cup-shaped hairspring 1 is taken out. Next, as shown in FIG. 8D, the outer end E2 of the spring material 2 is smoothly bent inside the spiral. There is no need to bend the outer end curve region R upward in the cup shape. For this reason, the outer end curve region R can be formed very easily even when the spring material 2 wide in the vertical direction of the spiral is used.

  In addition, the cross-sectional shape of the hairspring 1 having the cup shape is not limited to the U shape, and can be formed so as to satisfy the V shape or the expressions (1) to (4). Further, the spring material 2 of the hairspring 1 is not limited to the belt-shaped spring material 2 that is wide in the vertical direction of the spiral, and the cross-sectional shape may be a circle, an ellipse, a quadrangle, or the like.

(Sixth embodiment)
FIG. 9 is a schematic view of a timepiece including a movement including the hairspring 1 according to the sixth embodiment of the present invention. The same portions or portions having the same function are denoted by the same reference numerals.

  The timepiece 15 includes a barrel 16 that houses the mainspring 23, a train wheel 17 that transmits power accumulated in the mainspring 23, and an escapement unit 18 that restricts rotation of the train wheel 17. Other configurations such as a dial and a mainspring winding mechanism are omitted. The wheel train 17 is connected to a gear 17a, a second gear 17b, and a second gear 17b that are attached to the barrel 16, and is connected to a second pinion 17c, a third gear 17d, and a third gear 17d that engage with the gear 17a. A movement (not shown) including a third pinion 17e, a fourth gear 17f, a fourth gear 17f, and a fourth pinion 17g that engages with the third gear 17d and the like is incorporated. Is done.

  An example of the movement is a portion obtained by removing a so-called exterior portion (case, hour hand (not shown), etc.) from the watch 15, and the above-described mainspring 23 of the power source, the barrel 16 for storing the mainspring 23, It is configured to include a moving wheel train 17 and the like, an ankle escapement (regulator / escape mechanism) that controls the rotational speed of the gear, or a manual winding mechanism (not shown). is there.

  The escapement unit 18 includes an escape wheel 20 that receives power from the wheel train 17, an ankle 24 that restricts the rotation of the escape wheel 20, and a balance 19 that restricts the vibration period of the ankle 24. The balance with hairspring 19 is the cup-shaped hairspring 1 described in the first to fifth embodiments, the hair ball connected to the inner end E1 (not shown) of the hairspring 1, and the outer end E2 (not shown). And a balance wheel 5 connected to the balance spring 1 and serving as a rotary shaft of the reciprocating rotational movement by the hairspring 1, and a balance wheel 6 connected to the balance 5 and performing reciprocating rotational vibration.

  Thus, by using the cup-shaped hairspring 1 for the balance 19, it is possible to reduce the thickness of the timepiece and to configure a timepiece that displays time with high accuracy.

DESCRIPTION OF SYMBOLS 1 Balance spring 2 Spring material, 21 1st spring material, 22 2nd spring material 3 Whistle ball 4 Whistle 5 Spring stem 6 Balance wheel 7 Fitting groove 8 Through-hole 9 Flat hairspring 10 Concave type, 11 Convex Mold 12 Pushing pin 13 Frame 15 Timepiece, 17 Wheel train, 18 Escapement part, 19 End of balance E1 End of E2 End of outer K K Intersection R Outer end curve area H Inner end area

Claims (10)

  A hairspring having a cup shape in which a linear spring material is wound while expanding from the inside to the outside and upward. The spring material, counting from the outer end, the first and second rolls intersect in a plan view when viewing the cup shape from above,
The hairspring according to claim 1, wherein the spring material of the first volume and the spring material of the second volume are separated from each other at an intersecting portion where the spring materials intersect in plan view. Comprising a whisker ball connected to the inner end of the spring material;
The hairspring according to claim 1 or 2, wherein the whisker ball includes a fitting groove into which the spring material is fitted, and the fitting groove is inclined with respect to a vertical direction of the cup shape.   The hairspring according to any one of claims 1 to 3, wherein the cup shape has a U-shaped vertical cross-sectional shape.   A movement comprising the hairspring according to any one of claims 1 to 4.   A timepiece comprising the hairspring according to claim 1. A flat-spring mainspring forming process for forming a flat-plate flat-spring mainspring around which a spring material is wound;
A deformation step of deforming the flat hairspring into a cup shape;
And a heat treatment step of heat-treating the flat hairspring and brazing it into the cup shape. The deformation step is a step of pressing the convex mold relative to the concave mold by sandwiching the flat hair spring between the convex mold and the concave mold.
The method for manufacturing a hairspring according to claim 7, further comprising a removal step of removing the convex shape and the concave shape and taking out the cup-shaped hairspring after the heat treatment step. The deformation step is a step of sandwiching the flat balance spring between the convex mold and a plurality of pressing pins with the upper ends aligned, and pressing the convex mold relatively to the plurality of pressing pins,
The method for manufacturing a hairspring according to claim 7, further comprising a removing step of removing the convex mold and the plurality of pressing pins and taking out the cup-shaped hairspring after the heat treatment step.   The method of manufacturing a hairspring according to claim 9, wherein the deformation step is a step in which the pressing pin is inserted between the wound spring materials.

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