Waterproof closure device for watch case

Abstract

The invention relates to a waterproof closing device for a watch case, comprising an annular gasket (1) arranged to be placed between a middle piece (2) and a back cover (3), a bezel or a watch crystal (4), or between a bezel and a watch crystal, or between a back cover and a watch crystal, said gasket (1) having on its intermediate portion a protrusion (10) projecting on its outer side (11) arranged to engage against the middle piece (3) and to be compressed after mounting the back cover or the watch crystal on the middle piece, said protrusion being delimited in its uncompressed state of the gasket (1) by an upper material removal (12) and a lower material removal (13) located on either side of the protrusion (10) in order to facilitate its mounting and deformation.

Description

Technical Field

[0001] This invention relates to a waterproof sealing device for a watch case. It also relates to a watch case including such a device / system. Furthermore, it relates to a timepiece including such a device / system or such a watch case. Finally, this invention relates to a method for mounting such a timepiece or such a watch case. Background Technology

[0002] In the world of watchmaking, there is a constant pursuit of making watch cases as waterproof as possible and protecting their interiors from moisture that could generate steam and interfere with accurate timekeeping. In the long term, it is also necessary to protect all the internal metal parts that make up the movement from premature aging due to oxidation. This need for water resistance has proven particularly important for watches intended for immersion in water, such as dive watches.

[0003] A waterproofing device is known for a case back on a watch crystal, bezel, case back glass, or middle part, wherein the watch crystal, bezel, and / or case back are pushed and held in place on the middle part by means of a gasket made of a compressible material that achieves waterproofing.

[0004] Gaskets that have both waterproof and retaining functions are generally I-ring gaskets made of elastomer and are circular in shape.

[0005] A known problem associated with annular gaskets involves their susceptibility to compression when subjected to axial frictional or compressive forces during the pressing of the case back, bezel, or centerpiece and / or the glass on the case back. This can lead to partial or even complete breakage, and in all cases, significantly reduce the sought-after water resistance. To reduce the risk of such gaskets failing under deformational stress while improving their water resistance, gaskets with chamfered portions have been introduced. The bevel created by the chamfer increases the reliability of water resistance, while the reduced friction minimizes shear stress, thereby improving durability and lifespan.

[0006] However, when the compression ratio of the washer is high, there is still a risk of extrusion. Increased deformation of the washer causes material to accumulate at the bottom of the washer and form a foot, which makes the pressing operation difficult, or even impossible, and poses a challenge to the operator.

[0007] In addition, variations in the compression ratio inherent in machining tolerances can produce multiple levels of plastic deformation, which may compromise the quality of the process (a noticeable defect when closing, poor back cover closure visible during the day, and the risk of reduced water resistance).

[0008] Therefore, one objective of the present invention is to provide a gasket that improves sealing quality, is more robust and durable, and requires less force during pressing. Summary of the Invention

[0009] The present invention solves the above-mentioned disadvantages by proposing a gasket having a protrusion on one of its sides in its middle portion, which ensures both water resistance and retention / positioning between watch components.

[0010] Therefore, the present invention relates to a waterproof sealing device for a watch case, the waterproof sealing device comprising a gasket having an upper surface, a lower surface, an inner surface, and an outer surface, the gasket being arranged between a first element and a second element intended to be pressed against the first element, the gasket having material removal portions at opposite ends of one of its sides at a height h', thereby defining a protrusion of thickness e' on one of the sides of the gasket in the middle portion of the gasket, the protrusion being arranged to be compressed after the second element is mounted on the first element.

[0011] According to the present invention, the material removal part has a surface inscribed in a rectangle, the length of which corresponds to the height h', the width of which corresponds to the thickness e' of the protrusion, and the area of ​​which is Ar. The area As of the cross section of the material removal part is less than the area Ar of the rectangle and greater than half the area Ar / 2 of the rectangle.

[0012] Other advantageous variations according to the invention:

[0013] - The material removal section includes a first upper material removal section that can guide the first element onto the second element, and a second lower material removal section that can absorb plastic deformation of the protrusion at opposite ends of one side of the washer.

[0014] - The protrusion may be symmetrical or asymmetrical;

[0015] - The height of the washer is between 0.5mm and 2.0mm;

[0016] - The thickness of the gasket is between 0.3mm and 0.8mm;

[0017] - The height of the material removal section is between 0.1mm and 0.4mm;

[0018] - The thickness of the protrusion is between 0.05mm and 0.25mm;

[0019] - The washer has a radial cross section, the upper area S0 and the lower area S2 of which are both smaller than the middle area S1. These areas are determined in the undeformed state of the washer.

[0020] - The protrusion has a trapezoidal cross section, a raised cross section, or a sloping cross section.

[0021] The present invention also relates to a watch case comprising a middle component, a bezel, a back cover, a crystal, and a waterproof sealing device according to the present invention.

[0022] The present invention also relates to a watch comprising a waterproof sealing device and / or a housing according to the present invention. Attached Figure Description

[0023] Other features and advantages of the invention will become apparent upon reading the following detailed description, given by way of non-limiting example, with reference to the accompanying drawings, in which:

[0024] - Figure 1 A cross-sectional view of a device according to a preferred embodiment of the present invention is shown;

[0025] - Figure 2 The assembly to Figure 1 A cross-sectional view of the washer of the device;

[0026] - Figures 3a to 3c Cross-sectional views of various embodiments of gaskets equipped with the device according to the invention are shown. Detailed Implementation

[0027] The following is for reference. Figure 1 , Figure 2 and Figures 3a to 3c A first embodiment of a watch equipped with a device according to the present invention is described.

[0028] This invention relates to a waterproof sealing device for a watch case, the waterproof sealing device comprising a gasket 1 arranged between a first element and a second element intended to press against the first element. The first and second elements are selected from: a middle part, a case back, a bezel, and a watch crystal.

[0029] For ease of reading and understanding of the invention, only the description of the case back being pressed against the middle piece will follow. The description of the crystal being pressed against the middle piece, the crystal being pressed against the bezel, the crystal being pressed against the case back, or the bezel being pressed against the middle piece will obviously be similar.

[0030] The watch includes a watch case 100 and a watch movement designed to be housed within the watch case to protect it from external environmental influences. The watch movement can be an electronic or mechanical movement, especially an automatic movement.

[0031] The watch case 100 includes a middle part 2, a back cover 3, and a sealing gasket 1. The watch case may also include a rotating or non-rotating crystal and a bezel (not shown in the figure).

[0032] The back cover 3 is pushed against the middle component until it comes into contact with the middle component 2. The watch crystal itself is also pushed against the middle component, especially by the action of the sealing gasket.

[0033] The sealing gasket 1 is annular and has an upper surface, a lower surface, an inner surface, and an outer surface 11.

[0034] The gasket 1 includes a protrusion 10 protruding on one of its sides in its middle portion. The protrusion 10 is arranged to engage with the intermediate member 3 and is compressed between the back cover 2 and the intermediate member after the back cover 2 or the watch face is mounted on the intermediate member 3.

[0035] In the illustrated example, when the case back is pressed onto the center piece, the protrusion 10 protrudes from the outer surface. The protrusion 10 can protrude noticeably from the inner side of the gasket, a layout that is useful, for example, when the watch crystal is pressed onto the center piece, bezel, or case back.

[0036] The sealing gasket 1 is made of a deformable material, which allows it to be compressed.

[0037] Materials used for producing gaskets are selected from: asutane, TPU polyether PU or polyester PU, Pearlthane type polycaprolactone copolyester TPU, Isotane type polyadipate TPU, Pebax type polyether block amide TPU, Hytrel type polyester or Arnitel type polyether ester TPE, Grilamid type polyamide and copolyimide, Zytel, Rilsan; and Tefzel or Neoflon type fluoropolymers.

[0038] As in Figure 2 As can be observed, the material removal sections provided on both sides of the protrusion 10 form an upper free volume 12 and a lower free volume 13 in the uncompressed state of the washer 1. The upper free volume 12 and the lower free volume 13 each have different functions: the upper free volume facilitates the mounting of components, while the lower free volume absorbs deformation of the protrusion 10. Therefore, the upper free volume 12 and the lower free volume 13 prevent the washer 1 from being squeezed during the mutual pressing of components.

[0039] Advantageously, the gasket 1 has a radial cross section, the upper area S0 and the lower area S2 of which are both smaller than the middle area S1. These areas are determined in the undeformed state of the gasket. The middle part of the gasket ensures that the components retain / position each other and provides water resistance.

[0040] The material removal section includes a first upper material removal section 12, which allows the first element to be guided onto the second element, and a second lower material removal section 13, which allows the absorption of plastic deformation of the protrusion 10 at opposite ends on one side of the washer. Clearly, depending on the washer's mounting orientation, individual and identical free volume shapes can provide one function and another.

[0041] Each material removal section 12, 13 extends at a height h' and a thickness e' corresponding to the thickness of the protrusion 10, thereby defining a protrusion 10 protruding on one of its sides in its middle portion.

[0042] Advantageously, the material removal section has a surface inscribed in a rectangle whose length corresponds to the height h' and whose width corresponds to the thickness e' of the protrusion, has an area Ar, and the area As of the cross-section of the material removal section is less than the area Ar of the rectangle and greater than half the area Ar / 2 of the rectangle.

[0043] In other words, a right triangle is inscribed in the surface of the remaining material at the material removal section, with the vertex of the upper or lower surface of the washer and the vertex of the protrusion 10 as vertices. The two sides of the right triangle are parallel to the lateral edge and parallel to the upper and lower edges, and have a length corresponding to the height h' and a width corresponding to the thickness e'.

[0044] According to a preferred embodiment of the present invention, the protrusion 10 of the washer 1 is symmetrical about the mid-plane of the washer 1 (the plane that divides the washer at its center), such as... Figure 2 As shown. The protrusion can also be asymmetrical, such as... Figure 3c As shown. This also applies to the upper material removal section 12 and the lower material removal section 13.

[0045] As shown in the accompanying drawings illustrating multiple embodiments, the protrusion 10 has a trapezoidal cross section, a raised cross section, or even a sloping cross section.

[0046] exist Figure 2 In the preferred embodiment shown, the protrusion 10 has a trapezoidal shape, thereby forming a flat surface and then an inclined surface.

[0047] Washer 1 has a height h between 0.5 mm and 2.0 mm and a thickness e between 0.3 mm and 0.8 mm.

[0048] The material removal sections 12 and 13 include a height h between 0.1 mm and 0.4 mm and a thickness e between 0.05 mm and 0.25 mm.

[0049] The free volume at the bottom of the gasket can resolve issues related to machining tolerances, which may cause varying degrees of plastic deformation, thereby compromising the quality of the method of mounting the back cover 3 onto the intermediate piece 2 (a sense of defect when closing, poor closure of the back cover visible in sunlight, and the risk of reduced water resistance).

[0050] Similarly, the free volume on the upper part of the gasket allows for the formation of a free volume on its upper portion for guiding or pre-engaging, thereby preventing the gasket from being squeezed or damaged. In practice, depending on batch variations / possible situations (centering, positioning, etc.), gasket engagement may be performed with coplanarity and / or concentricity defects. Pressure concentration occurs on the constrained portion of the gasket, and the gasket is damaged, for example, by being caught in the middle.

[0051] The following describes a method for installing an apparatus comprising a rear cover 3, a middle component 2, and a gasket 1 according to the present invention.

[0052] In the first step, the washer 1 is pushed / pushed onto the back cover 3, abutting against the shoulder 30 of the back cover 3.

[0053] In the second step, the back cover 3 is positioned opposite the middle piece 2.

[0054] In the third step, the assembly of the back cover 3 and the gasket 1 is pushed into the middle part 2 until the back cover 3 abuts against the shoulder 20 of the middle part 2, and then the gasket 1 is compressed between the middle part 2 and the back cover 3.

[0055] Once the entire assembly is complete, the device 10 forms the waterproof system of the watch case 100 at the interface between the intermediate part 2 and the back cover 3.

[0056] Clearly, a similar installation method can be implemented to mount the watch face onto the intermediate piece.

[0057] The present invention also relates to a watch case 100, which includes a middle part 2, a back cover 3, a watch crystal, and a waterproof closure device according to the present invention.

[0058] The present invention also relates to watches including a waterproof closure and / or a case according to the present invention.

Claims

1. A waterproof sealing device for a watch, the waterproof sealing device comprising a gasket (1) having an upper surface, a lower surface, an inner surface, and an outer surface (11), the gasket (1) being arranged between a first element (2) and a second element (3), the second element being intended to be pressed against the first element, the gasket (1) having material removal portions (12, 13) at a height (h') at opposite ends of one of its sides, thereby defining a protrusion (10) of thickness (e') projecting from the side of the gasket (1) at the middle portion of the side, the protrusion (10) being arranged to be compressed after the second element (3) is mounted on the first element (2), Its features are, The material removal section (12, 13) has a surface inscribed within a rectangle, the length of which corresponds to the height (h'), the width of which corresponds to the thickness (e') of the protrusion, and the rectangle has an area A. r And the area A of the cross-section of the material removal section (12, 13) s Smaller than the area A of the rectangle r And greater than half the area A of the rectangle r / 2.

2. The waterproof sealing device according to claim 1, characterized in that, The material removal portions (12, 13) form a first upper material removal portion (12) and a second lower material removal portion (13), the first upper material removal portion enabling the first element to be guided on the second element, and the second lower material removal portion enabling the absorption of plastic deformation of the protrusion (10).

3. The waterproof sealing device according to claim 1 or 2, characterized in that, The protrusion (10) and / or the material removal portion (12, 13) are symmetrical or asymmetrical.

4. The waterproof sealing device according to claim 1 or 2, characterized in that, The height (h) of the washer (1) is between 0.5 mm and 2.0 mm.

5. The waterproof sealing device according to claim 1 or 2, characterized in that, The thickness (e) of the gasket (1) is between 0.3 mm and 0.8 mm.

6. The waterproof sealing device according to claim 1 or 2, characterized in that, The height (h') of the material removal section (12, 13) is between 0.1 mm and 0.4 mm.

7. The waterproof sealing device according to claim 1 or 2, characterized in that, The thickness (e') of the protrusion (10) is between 0.05 mm and 0.25 mm.

8. The waterproof sealing device according to claim 1 or 2, characterized in that, The washer (1) has a radial cross section, the upper area (S0) and the lower area (S2) of which are both smaller than the middle area (S1), and the upper area, the lower area and the middle area are determined in the undeformed state of the washer (1).

9. The waterproof sealing device according to claim 1 or 2, characterized in that, The protrusion (10) has a trapezoidal cross section, a raised cross section, or a sloping cross section.

10. A watch case (100) comprising a middle part, a back cover, a watch crystal, and a waterproof sealing device according to any one of the preceding claims.

11. A watch comprising a waterproof sealing device according to any one of claims 1 to 9 and / or a watch case according to claim 10.

Images