Patent Application
20110045249
The present invention relates to a sliding component used as a timepiece component such as a cogwheel or a bearing.
As a method of manufacturing a sliding component of high dimensional precision such as a small cogwheel, there is employed a technique combining photolithography and electroforming (See, for example, Patent Document 1). A sliding component involves generation of friction due to a mutual action between itself and a component held in contact therewith. If the regions of these components in contact with each other lack wear resistance, these components will be worn early. The efficiency of a mechanism using the sliding component is markedly affected by wear. In view of this, in order to achieve an increase in wear resistance, a lubricating oil is used. However, being a liquid, the lubricating oil does not remain at the sliding portion but there is danger of its being dispersed over the entire sliding component or to other components. In view of this, some sliding components adopt a structure which retains the lubricating oil at the sliding portion (See, for example, Patent Document 2).
In the structure disclosed in Patent Document 1, the sliding portion is smooth, so that any lubricating oil used does not remain at the sliding portion but is quite likely to be dispersed.
The structure disclosed in Patent Document 2 adopts a lubricating oil retaining structure, so that the possibility of the lubricating oil being dispersed is low.
The escape tooth 501 retains a lubricating oil 410 at a lubricating oil retaining portion 521, so that the lubricating oil 410 is not dispersed but remains at the sliding portion. As shown in
Also in a case in which the escape tooth 501 and the pallet 210 are held in contact with each other while inclined as shown in
It is an object of the present invention to provide a sliding component of high wear resistance having a lubricating oil retaining structure for supplying a lubricating oil independently of the angle between itself and the mating component, and a timepiece.
According to the present invention, there is provided a sliding component in which at least three layers are stacked together and which has a sliding portion sliding on another component on an outer peripheral surface substantially parallel to the direction in which the layers are stacked, characterized in that there is formed a recess in a sliding portion of at least one internally situated layer between an uppermost layer and a lowermost layer of the at least three layers stacked together. According to this invention, the recess constituting a lubricating oil retaining portion is not situated on one side of the stacking direction, so that it is possible to reliably supply the lubricating oil without being much affected by the contact angle between the sliding component and the mating component, making it possible to obtain a sliding component of high wear resistance.
In the sliding component of the present invention, the recess may be formed by causing at least one internally situated layer between the uppermost and the lowermost layers of the at least three layers stacked together to recede.
The sliding component of the present invention is characterized in that there are provided a plurality of recesses as mentioned above in the stacking direction. According to this invention, the sliding component is less subject to the influence of the contact angle between itself and the mating component, making it possible to supply the lubricating oil more reliably.
The sliding component of the present invention is characterized in that the recess is formed over the entire periphery of the outer peripheral surface. According to this invention, it is possible to augment the amount of lubricating oil retained in the recess.
The sliding component of the present invention may be of a structure in which at least three layers formed of at least two different kinds of materials are stacked together. In this connection, the material of one layer of the layers may be of higher heat conductivity than the material of the other layers.
The sliding component of the present invention is characterized in that at least one of protrusion layers protruding with respect to the layer forming the recess has a curved surface at a crossing portion between a surface substantially perpendicular to the stacking direction and a surface substantially parallel thereto.
The sliding component of the present invention is characterized in that the at least three layers comprise a predetermined layer, and a first opposing layer and a second opposing layer which are opposed to the predetermined layer in the thickness direction of the predetermined layer, that the recess is formed by causing the predetermined layer to recede from the outer peripheral surface of the first opposing layer or the second opposing layer, and that at least one of the first opposing layer and the second opposing layer has a curved surface at a crossing portion between a surface substantially perpendicular to the stacking direction and a surface substantially parallel thereto.
The sliding component of the present invention is characterized in that at least one of the first opposing layer and the second opposing layer has the curved surface on the former of a predetermined layer side where the predetermined layer is formed and aside opposite to the predetermined layer side.
The sliding component of the present invention is characterized in that at least one of the first opposing layer and the second opposing layer has the curved surface on the latter of a predetermined layer side where the predetermined layer is formed and a side opposite to the predetermined layer side.
The sliding component of the present invention is characterized in that at least one of the first opposing layer and the second opposing layer has the curved surface on both of a predetermined layer side where the predetermined layer is formed and a side opposite to the predetermined layer side.
The sliding component of the present invention is characterized in that it is used as a timepiece component.
A timepiece according to the present invention is characterized in that it is equipped with a sliding component according to the present invention.
According to the present invention, there is provided a sliding component manufacturing method comprising the steps of: forming a photosensitive material layer on an upper surface of a conductive substrate; exposing the photosensitive material via a mask pattern arranged above the photosensitive material; developing the photosensitive material to form a cavity consisting of the photosensitive material and an exposed surface of the conductive substrate; depositing at least two or more kinds of material layers on the exposed surface of the conductive substrate in the cavity by electroforming; extracting the deposited Material layers from the cavity; and selectively removing a part of the surfaces of the material layers.
According to the present invention, it is possible to provide a sliding component of superior wear resistance having a lubricating oil retaining structure, and a timepiece employing this sliding component as a timepiece component to thereby achieve an increase in maintenance period. Further, according to the manufacturing method of the present invention, it is possible to easily manufacture a sliding component of superior wear resistance having a lubricating oil retaining structure.
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In the following, a first embodiment of the present invention will be described with reference to the drawings.
Here, the timepiece 1 is a two-hand type mechanical timepiece. However, the timepiece may also be an electronic control type mechanical timepiece, a quartz type timepiece, etc.
The timepiece 1 is equipped with a movement barrel 2 equipped with a mainspring 2B, a barrel cogwheel 2A, a barrel arbor 2C, and a barrel cover 2D. An external end of the mainspring 2B is fixed to the barrel cogwheel 2A, and an internal end thereof is fixed to the barrel arbor 2C. The barrel arbor 2C is supported by a main plate 3 and a train wheel bridge 4, and is fixed in position by a ratchet wheel screw so as to rotate integrally with a ratchet wheel 5. The ratchet 5 is in mesh with a click 7 so as to rotate clockwise but not to rotate counterclockwise. The method of winding the mainspring 2B is the same as the self-winding and the manual winding of an ordinary mechanical timepiece, so that a description thereof will be omitted.
The rotation of the barrel cogwheel 2A is increased in speed via a speed increasing train wheel 11 composed of a center wheel & pinion 12, a third wheel & pinion 13, and a second wheel & pinion 14, and is then transmitted to the balance with hairspring 10 via an escape wheel & pinion 100 and a pallet fork 200.
A cannon pinion 15 is fixed to the second wheel & pinion 12 of the speed increasing train wheel 11, and a minute hand 8 is fixed to the cannon pinion 15. Based on the rotation of the cannon pinion 15, an hour wheel 16 is rotated via the rotation of a minute wheel (not shown). An hour hand 9 is fixed to the hour wheel 16. That is, the indicator hands 8, 9 are connected to the speed increasing train wheel 11, and the barrel cogwheel 2A and the cogwheels of the wheels & pinions 12 through 14 used in the speed increasing train wheel 11 are used as cogwheels driving the indicator hands 8, 9 of the timepiece 1. Thus, high dimensional precision and wear resistance are required of each timepiece component.
The timepiece 1 has various train wheels; in the following description, for the sake of simplicity, the escape wheel & pinion 100 will be taken as an example. It should be noted, however, that the escape wheel & pinion is only taken as an example to facilitate the understanding of the present invention.
a) shows the escape wheel & pinion (sliding component) 100 having a structure according to the present invention. The escape wheel & pinion 100 has a plurality of escape teeth 101 in the outer periphery thereof, and an axial hole 102 extending in the thickness direction at the center thereof. The escape wheel & pinion 100 is a component used as a timepiece component of the mechanical timepiece shown in
b) is an enlarged view of the portion of an escape tooth 101 enclosed by a circle C in
Examples of the material of the first and third metal layers 121, 123 include metals such as nickel (Ni), cobalt (Co), platinum (Pt), rhodium (Rh), chromium (Cr), and palladium (Pd), alloys such as Ni-tungsten (W) and Ni-boron (B), and composites obtained as eutectoid, in the matrix of one of the above-mentioned metals, of particles or fibers of ceramics such as alumina (Al2O3) or silicon carbide (SiC), or a resin such as polytetrafluoroethylene (PTFE), or some other organic or inorganic substance. Examples of the material of the second metal layer 122 include metals such as copper (Cu), gold (Au), zinc (Zn), silver (Ag), iron (Fe), and tin (Sn), alloys such as Cu—Au and Cu—Ag, or a composite obtained as eutectoid of the particles or fibers as mentioned above in the matrix of one of the above metals. In the manufacturing process described below, in order to form a recess 150 in the second metal layer 122 through etching, there is adopted a combination of materials allowing selective etching of the second metal layer 122 only, or a combination of materials involving a difference in etching rate. Since the escape wheel & pinion 100 is a sliding component, it is desirable for the first and third metal layers 121, 123 which come into contact with the mating component to be formed of a hard material.
c) is a sectional view of the escape wheel & pinion 100 taken along the line X-X of
In this embodiment, the thickness T0 of the escape wheel & pinion 100 is 100 μm. The thickness T0 is set to 10 μm to 1 mm according to the component to be manufactured. The thickness T1 of the first metal layer 121 and the thickness T3 of the third metal layer 123 range from 1 μm to 900 μm. It is not necessary for the thickness T1 and the thickness T3 to be of the same value. The thickness T2 of the second metal layer 122 is set to 500 nm to 500 μm. The depth W1 of the recess 150 is set to 1 μm to 1 mm. The thickness T2 and the depth W1 determining the size of the recess 150 are determined as appropriate according to the viscosity and surface tension of the lubricating oil.
The escape wheel & pinion 100 slides on a pallet fork 200. More specifically, escape teeth 101 of the escape wheel & pinion 100 slide on pallets 210 of the pallet fork 200.
The process in which the escape tooth 101 slides on the pallet 210 will be described with reference to
When the pallet fork moves in the direction of the arrow, a state is attained in which the rocking corner 114 of the escape tooth 101 and the rocking corner 214 of the pallet 210 are held in contact with each other as shown in
And, a state is attained in which the rocking corner 114 of the escape tooth 101 and the let-off corner 215 of the pallet 210 are held in contact with each other as shown in
When the let-off corner 115 of the escape tooth 101 and the let-off corner 215 of the pallet 210 are brought into contact with each other as shown in
In the sliding process shown in
The recess 150 is provided over the entire periphery of the escape wheel & pinion 100, so that, in all of the states of the sliding process illustrated with reference to
In the escape wheel & pinion 100, the lubricating oil 410 is supplied from the recess 150 to the sliding portion more reliably, whereby an improvement in terms of sliding property is achieved. As a result, the escape wheel & pinion 100 is improved in terms of wear resistance, and the service life of the components becomes longer than that in the prior art.
Further, the recess 150 is provided in the entire periphery of the escape wheel & pinion 100, so that the oil retaining amount is larger than that of an escape wheel & pinion of a conventional structure. A mechanical timepiece requires maintenance for oiling the sliding components every several years; by using a sliding component of the structure of the present invention, it is possible to elongate the inter-maintenance period as compared with the prior art.
In the following, a method of manufacturing an escape wheel & pinion 100 of the structure of the present invention will be described with reference to
a) is a diagram illustrating a process for forming a conductive substrate. An electrode material 602 is formed on a substrate 601. The substrate 601 is formed of silicon, quartz, sapphire or the like. The electrode material 602 consists of Cu, Au, Cr, Ti or the like. It is also possible to form the substrate 601 of a metal such as stainless steel or Ti. In the case in which the substrate 601 is formed of a metal, there is no need to form the electrode material 602. The thickness of the substrate 601 is set to 100 μm to 1 mm so that it can support itself in the processes described below. The thickness of the electrode material 602 is set to 10 nm to 10 μm.
b) is a diagram illustrating a resist forming process. A photo resist 603 is deposited on the electrode material 602. The photo resist 603 may be of either the negative type or the positive type. The photo resist 603 is formed by spin coating, dip coating or the like. When using a dry film resist as the photo resist 603, it is formed on the electrode material 602 by a laminating method. The thickness of the photo resist 603 is not less than the thickness T0 of the escape wheel & pinion 100. In the following, the case will be described in which the photo resist 603 is of the negative type.
c) is a diagram illustrating a developing process. Using a photo mask with a contour pattern of the escape wheel & pinion 100, the photo resist 603 is irradiated with ultraviolet rays, thereby curing the portion of the resist other than that used for electroforming of the escape wheel & pinion 100. The uncured resist portion is removed, whereby the electroforming mold is completed. A side surface 631 of a photo resist 603K has a configuration corresponding to the contour of the escape wheel & pinion 100. A side surface 632 of a photo resist 603L has a configuration corresponding to that of the axial hole 102.
d) through 9(a) are diagrams illustrating an electroforming process. The first metal layer 121, the second metal layer 122, and the third metal layer 123 are stacked together in that order such that the second metal layer 122 is between the first and third metal layers 121, 123. The electroformed product grows solely from the bottom surface.
d) is a diagram illustrating a metal layer electroforming process. The first metal layer 121 is deposited on the mold portion on the electrode material 602 other than the photo resists 603K, 603L to a thickness of T1.
e) is a diagram illustrating a metal electroforming process. The second metal layer 122 is deposited on the second metal layer 122 to a thickness of T2. The sum total of the thickness T1 and the thickness T2 is smaller than the thickness T0.
a) is a diagram illustrating a metal electroforming process. The third metal layer 123 is deposited on the second metal layer 122 to a thickness of not less than T3 so that the thickness of the electroformed product may be not less than the thickness T0 of the escape wheel & pinion. However, in the case in which the grinding/polishing process shown in
b) is a diagram illustrating the grinding/polishing process. Through grinding, the third metal layer 123 and the photo resists 603K, 603L are cut such that the thickness of the escape wheel & pinion 100 becomes T0, thereby effecting flattening. Polishing is further performed to form the surface of the third metal layer 123 as a mirror surface.
c) is a diagram illustrating a resist removal process. The photo resists 603K, 603L are removed by etching, physical force or the like.
d) is a diagram illustrating a recess forming process. An electroformed product is immersed in an etching liquid which effects etching on the second metal layer 122 but which does not effect etching on the first and third metal layers 121, 123. Etching is effected only on the second metal layer 122 to form the recess 150 having a depth W1. For example, in the case in which Ni is deposited on the first and third metal layers 121, 123 and in which Cu is deposited on the second metal layer 122, it is possible to effect etching solely on the Cu by using an ammonium persulfate solution as the etching liquid.
e) is a diagram illustrating an electroformed product separating process. The substrate 601 and the electrode 602 are removed by etching, physical force or the like.
The processes shown in
a) is a diagram illustrating a substrate/electrode removal process. The substrate 601 and the electrode 602 are removed by etching or the like.
b) is a diagram illustrating a resist removal process. The photo resists 603K, 603L are removed by etching, physical force or the like.
c) is a diagram illustrating a recess forming process. An electroformed product is immersed in an etching liquid which effects etching on the second metal layer 122 but which does not effect etching on the first and third metal layers 121, 123. Etching is effected only on the second metal layer 122 to form the recess 150 of the depth W1.
When an improvement in functions such as corrosion resistance, lubrication property, and heat resistance is to be achieved, and when the oil retaining property is to be improved by increasing wettability, there is added a plating process shown in
As described above, according to the manufacturing method of the present invention, it is possible to easily manufacture the sliding component shown in
In the case in which there is used, as the material of the second metal layer 122, a composite obtained through eutectoid reaction of particles of PTFE, acrylic resin or the like in the metal matrix of Ni, Cu or the like, the recess can also be formed by the process shown in
In some cases, the escape wheel & pinion 100 involves generation of friction heat during sliding, and the temperature of the sliding portion increases to reduce the hardness of the material forming the escape wheel & pinion 100, making it subject to wear. However, in the present invention, by using a material of high heat conductivity for the second metal layer 122, it is possible to improve the heat conductivity of the entire escape wheel 6 pinion 100, and it becomes hard for the temperature of the first and third metal layers 121, 123 to rise, so that the layers become resistant to wear. In an example of such combination of metals, Ni is used for the first and third metal layers 121, 123, and Cu is used for the second metal layer 122.
Further, by adopting the configuration shown in
A method of manufacturing the escape wheel & pinion 100 having the structure shown in
a) and 15(c) are diagrams illustrating a barrel polishing process. After the process of
b) and 15(d) are diagrams illustrating a recess forming process. An electroformed product is immersed in an etching liquid which effects etching on the second metal layer 122 but does not effect etching on the first and third metal layers 121, 123. Etching is effected only on the second metal layer 122 to form the recess 150 of the depth W1.
The process illustrated in
a) is a diagram illustrating a wet etching process. An electroformed product is immersed in an etching liquid which effects etching on the first and third metal layers 121 and 123 but does not effect etching on the second metal layer 122. Etching is effected only on the first and third metal layers 121 and 123 to form curved surfaces 161A, 161B, 163A, and 163B. For example, in the case in which Cr is deposited on the first and third metal layers 121, 123 and in which Cu is deposited on the second metal layer, it is possible to effect etching solely on the Cr by using a potassium ferricyanide solution as the etching liquid.
b) is a diagram illustrating a recess forming process. An electroformed product is immersed in an etching liquid which effects etching on the second metal layer 122 but does not effect etching on the first and third metal layers 121, 123. Etching is effected solely on the second metal layer 122 to form the recess 150 of the depth W1.
In the case in which the escape wheel & pinion 100 has the curved surfaces 161B, 163B, it is possible to mitigate the stress when a shaft is driven into the axial hole 102, thereby preventing breakage.
Further, also by adopting the configuration shown in
A method of manufacturing the escape wheel & pinion 100 of the structure shown in
a) is a diagram illustrating a sacrifice layer electroforming process. After the step of
b) is a diagram illustrating a metal layer electroforming process. The first metal layer 121 is deposited on the first sacrifice layer 141 to a thickness T1. The second metal layer 122 is deposited thereon to a thickness T2. The third metal layer 123 is deposited thereon to a thickness of not less than T3 so that the thickness of the electroformed product may exceed the thickness T0 of the escape wheel & pinion 100.
c) is a diagram illustrating a grinding/polishing process. Through grinding, the third metal layer 123 and the photo resists 603K, 603L are cut so that the escape wheel & pinion 100 may attain the thickness T0 to thereby effecting flattening. Further, polishing is performed to finish the surface of the third metal layer 123 as a mirror surface.
d) is a diagram illustrating a sacrifice layer electroforming process. The second metal layer 142 is deposited on the third metal layer 123. The second sacrifice layer 142 is formed of Au, Cr, Ni, Cu or the like. The thickness of the second sacrifice layer 142 is set to 10 nm to 10 μm.
e) is a diagram illustrating a substrate/electrode removal process. The substrate 601 and the electrode 602 are removed by etching or the like.
f) is a diagram illustrating a resist removal process. The photo resists 603K, 603L are removed by etching, physical force or the like.
g) is a diagram illustrating a recess forming process. An electroformed product is immersed in an etching liquid which effects etching on the second metal layer 122 but does not effect etching on the first and third metal layers 121, 123 and the first and second sacrifice layers 141, 142. Etching is effected only on the second metal layer 122 to form the recess 150 of the depth W1. For example, in the case in which Ni is deposited on the first and third metal layers 121, 123, in which Cu is deposited on the second metal layer 122, and in which Cr is deposited on the first and second sacrifice layers 141, 142, it is possible to effect etching solely on the Cu by using an ammonium persulfate solution as the etching liquid.
h) and 18(j) are diagrams illustrating a barrel polishing process. The electroformed product is polished with a barrel to form the curved surfaces 161C, 163C. The radius of the curved surfaces 161C, 163C can be adjusted according to the barrel polishing condition. As shown in
i) and 18(k) are diagrams illustrating a sacrifice layer removal process. An electroformed product is immersed in an etching liquid which effects etching on the first and second sacrifice layers 141, 142 but does not effect etching on the first and third metal layers 121, 123, and the second metal layer 122. Etching is effected only on the first and second sacrifice layers 141, 142 to remove the sacrifice layers. For example, in the case in which Ni is deposited on the first and third metal layers 121, 123, in which Cu is deposited on the second metal layer 122, and in which Cr is deposited on the first and second sacrifice layers 141, 142, it is possible to effect etching solely on the Cr by using a potassium ferricyanide solution as the etching liquid.
The process shown in
a) is a diagram illustrating a metal layer electroforming process. The first metal layer 121 is deposited on the first sacrifice layer 141 to a thickness T1. The second metal layer 122 is deposited thereon to a thickness T2. The third metal layer 123 is deposited thereon to a thickness T3. The sum total of the thickness of the first sacrifice layer and the thickness T1, the thickness T2, and the thickness T3 is smaller than the thickness of the photo resists 603K, 603L.
b) is a diagram illustrating a sacrifice layer electroforming process. The second metal layer 142 is deposited on the third metal layer 123.
The process shown in
a) is a diagram illustrating a wet etching process. An electroformed product is immersed in an etching liquid which effects etching on the first and third metal layers 121 and 123 but does not effect etching on the second metal layer 122 and the first and second sacrifice layers 141, 142. Etching is effected only on the first and third metal layers 121 and 123 to thereby form the curved surfaces 161C, 161D, 163C, and 163D. For example, in the case in which Ni is deposited on the first and third metal layers 121, 123, in which Cr is deposited on the second metal layer, and in which Cu is deposited on the first and second sacrifice layers 141, 142, it is possible to effect etching solely on the Ni by using a nickel selective etching liquid —NC (manufactured by Nippon Chemical Industry Kabushiki Kaisha) as the etching liquid.
The process shown in
a) is a diagram illustrating a resist removal process. The photo resists 603K, 603L are removed by etching, physical force or the like.
b) is a diagram illustrating a recess forming process. An electroformed product is immersed in an etching liquid which effects on the second metal layer 122 but does not effect etching on the first and third metal layers 121, 123 and the first and second sacrifice layers 141, 142. Etching is effected only on the second metal layer 122 to form the recess 150 of the depth W1.
c) is a diagram illustrating a wet etching process. An electroformed product is immersed in an etching liquid which effects etching on the first and third metal layers 121 and 123 but does not effect etching on the second metal layer 122 and the first and second sacrifice layers 141, 142. Etching is effected only on the first and third metal layers 121 and 123 to thereby form the curved surfaces 161C, 161D, 163C, and 163D.
d) is a diagram illustrating an electroformed product separating process. The substrate 601 and the electrode 602 are removed by etching, physical force or the like.
e) is a diagram illustrating a sacrifice layer removal process. An electroformed product is immersed in an etching liquid which effects on the first and second sacrifice layers 141, 142 but does not effect etching on the first and third metal layers 121, 123 and the second metal layer 122. Etching is effected only on the first and second sacrifice layers 141, 142 to remove the sacrifice layers.
By using the configuration as shown in
Further, due to the provision of the configuration shown in
Further, in the case in which the curved surfaces 161A and 161C, and 163A and 163C, are connected with each other and in which the entire outer peripheral surface of the escape wheel & pinion 100 is a curved surface, it slides on the pallet 210 while in point contact therewith, so that an improvement is achieved in terms of lubrication property and wear resistance.
A method of manufacturing the escape wheel & pinion 100 of the structure shown in
a) and 23(b) are diagrams illustrating a barrel polishing process. After the process of
The process shown in
a) is a diagram illustrating a wet etching process. An electroformed product is immersed in an etching liquid which effects etching on the first and third metal layers 121 and 123 but does not effect etching on the second metal layer 122. Etching is effected only on the first and third metal layers 121 and 123 to thereby form the curved surfaces 161A, 161B, 161C, 161D, 163A, 163B, 163C, and 163D.
In the case in which the escape wheel & pinion 100 has the curved surfaces 161B, 161D, 163B, and 163D, it is possible to mitigate the stress when driving a shaft into the axial hole 102, thereby preventing breakage.
In the second embodiment described above, the effect of the first embodiment is further enhanced. In the following, a case will be described in which n is an odd number and in which the uppermost layer and the lowermost layer are metal layers of a larger outer dimension. In this case, the uppermost layer and the lowermost layer are metal layers that do not undergo etching, so that even when etching is effected on the metal layers to reduce the outer dimension in order to form a recess, there is advantageously no variation in the thickness TO of the escape wheel & pinion 700.
Here, suppose n=2 m+1 (m is an integer of 2 or more). The sliding component 700 has (m+1) first, third, . . . metal layers of a larger outer dimension and m second, fourth, . . . metal layers of a smaller outer dimension, with these metal layers being alternately stacked together in the thickness direction.
In the escape wheel & pinion 700, the outer dimension of the second, fourth, . . . metal layers 712, 714, . . . is smaller than the outer dimension of the first, third, . . . metal layers 711, 713, . . . ). The outer peripheral surfaces of the second, fourth, . . . metal layers 712, 714, . . . are recessed from the outer peripheral surface of the escape wheel & pinion 700 (the outer peripheral surfaces of the first, third, . . . metal layers 711, 713, . . . ). Thus, in this embodiment, the escape wheel & pinion 700 has, dispersed in the thickness direction, m recesses 750 that are not open in the thickness direction of the escape wheel & pinion 100, at least in a part of the sliding portion, over the entire periphery of the outer peripheral surface of the escape wheel & pinion 700. The recesses 750 serve to retain the lubricating oil.
As shown in
Further, when the pallet 210 has surface irregularities as shown in
Further, as shown in
As shown in
Further, when, as shown in
Further, since the escape wheel & pinion 700 has a plurality of recesses 750 for retaining the lubricating oil, so that the amount of lubricating oil 410 retained is large. Thus, the inter-maintenance period of can be made longer than that in the first embodiment.
The thickness T0 of the escape wheel & pinion 700 is the same as the thickness T0 in the first embodiment. The thicknesses T1 through T2m+1 of the metal layers are the same as the thicknesses T1, T3 in the first embodiment. It is not necessary for the thicknesses T1 through T2m+1 to be of the same value. The thicknesses T2 through T2m are the same as the thickness T2 in the first embodiment. It is not necessary for the thicknesses T2 through T2m to be of the same value. The depth W1 of the recess W1 is the same as the depth W1 in the first embodiment.
The method of manufacturing the escape wheel & pinion 700 is the same as that in the first embodiment. However, the electroforming process shown in
While in the above embodiments described above an escape wheel & pinion is taken as an example of the sliding component, this should not be construed restrictively; the present invention is also applicable to timepiece components such as a center, third, and second wheel & pinion, a ratchet wheel, a movement barrel, a click, and a crown wheel of a mechanical timepiece.
Further, the present invention is applicable not only to timepiece components but also to sliding components such as a cogwheel of an endoscope advancing/retreating apparatus, and a gear of a drive apparatus of a toy vehicle.
According to the present invention, it is possible to provide a sliding component having a lubricating oil retaining structure and superior in wear resistance, and a timepiece whose inter-maintenance period is elongated by using this sliding component as a timepiece component. Further, according to the manufacturing method of the present invention, it is possible to easily manufacture a sliding component having a lubricating oil retaining structure and superior in wear resistance.
100, 700 escape wheel & pinion
101, 701 escape tooth
102 axial hole
121, 711 first metal layer (first opposing layer)
122, 712 second metal layer
123, 713 third metal layer (second opposing layer)
150, 750 recess
210 pallet
410 lubricating oil
| Number | Date | Country | Kind |
|---|---|---|---|
| 2008-039863 | Feb 2008 | JP | national |
| 2008-232941 | Sep 2008 | JP | national |
| 2009-003612 | Jan 2009 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2009/052732 | 2/18/2009 | WO | 00 | 10/12/2010 |
