Fastening structure, optical device, molding device, and method for manufacturing article

Abstract

To provide a fastening structure that can reduce the problem of loosening and damage due to a change in temperature.SOLUTION: A fastening structure is composed of a fastening member 31 that can be screwed with a member to be fastened 1 and is formed of second material, and a second member 32 that is fastened to the member to be fastened 1 together with a first member 2 and includes a first material component part 321 and a second material component part 322 different from the first material. The difference between a length B322 effective for fastening of the second material component part 322 and a length B31 effective for fastening of the fastening member 31 when a fastener 3 is fastened to the member to be fastened 1 is equal to or less than a predetermined threshold. The difference between a length A2 effective for fastening of the first member 2 and a length A321 effective for fastening of the first material component part 321 when the fastener 3 is fastened to the member to be fastened 1 is equal to or less than the predetermined threshold.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a fastening structure, an optical device, a molding device, and a method for manufacturing an article. [Background technology]

[0002] Bolted fastening is widely used to fasten components together due to its advantages, such as ease of fastening, high fastening strength, manageability of fastening strength, ability to attach / detach and fine-adjust, and compact size. Unlike welding or adhesive bonding, bolted fastening does not place many restrictions on the materials of the components, and it is easy to fasten dissimilar materials such as aluminum and steel, or ceramics and metals.

[0003] The high fastening force of bolts (fastening components) is effective for fastening heavy objects and structures that are subjected to high forces. Another advantage of bolt fastening is that it is possible to control the axial force. Because of this advantage, bolt fastening is useful for precision optical equipment, and bolt fastening is superior as a fastening method that can satisfy the high installation accuracy of the parts that make up the optical system.

[0004] On the other hand, even in bolted joints, if the bolt and the fastened parts are made of different materials, the axial force will change due to temperature differences, creating the risk of loosening the joint or damage to the parts. Depending on the equipment used, the temperature of some parts may rise to several hundred degrees Celsius during operation. In order to minimize deterioration of the shape and positional relationship of parts under such high temperatures, the materials and arrangement of various parts are carefully designed, but fastening parts made of different materials is unavoidable, and there are concerns about minute deformation and damage to the parts.

[0005] In response to this issue, Patent Document 1 proposes a structure that keeps the axial force constant by compensating for the thermal expansion of dissimilar materials. Figure 8 is a diagram illustrating the configuration of Patent Document 1. In the structure of Patent Document 1, a steel member (fastened member) 802, which has a small linear expansion coefficient, is fastened to a base material 801 using a bolt 803, which has a large expansion coefficient. The steel member 802 is then fastened via a sleeve washer 804, which has a larger linear expansion coefficient than the bolt. With this structure, the difference in expansion between the bolt 803 and the steel member 802 when the temperature rises is compensated for by the large expansion of the sleeve washer 804, thereby keeping the bolt axial force constant. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 61-200311 Summary of the Invention [Problem to be solved by the invention]

[0007] However, Patent Document 1 has a problem in that it cannot avoid the temperature dependency of the linear expansion coefficient of the material. For example, it is known that materials such as aluminum exhibit temperature dependency where the linear expansion coefficient varies depending on the temperature. Because the temperature dependency characteristics of the linear expansion coefficient differ depending on the type of metal, the method of Patent Document 1 makes it difficult to maintain a relationship that compensates for expansion over a wide temperature range.

[0008] Furthermore, in Patent Document 1, it is necessary to accurately determine the dimensions and linear expansion coefficient of each material, but the measurement order of the linear expansion coefficient is one order of magnitude higher than the order of dimensional control (measurement and processing), as shown in the following example, making strict control difficult. Linear expansion coefficient: 20 ppm / K Measurement accuracy: ±0.2 ppm Dimensions: 20mm Control accuracy ±0.02mm

[0009] Furthermore, the configuration of Patent Document 1 requires that the materials used for each component have a linear expansion coefficient other than that of the bolt 803 and the steel component 802, which places restrictions on material selection. As a result, due to the temperature dependency of the linear expansion coefficient of the material, it is difficult to achieve a relationship that compensates for expansion over a wide temperature range, which can lead to the problem of loosening or damage to the components used for fastening, such as bolts.

[0010] Therefore, an object of the present invention is to provide a fastening structure that can reduce the problems of loosening and breakage due to temperature changes, for example. [Means for solving the problem]

[0011] In order to achieve the above object, a fastening structure according to one aspect of the present invention is a fastening structure for fastening a first member placed on a predetermined surface of a fastened member to the fastened member using a fastener, the fastener including a fastening member configured to be able to be threadedly engaged with the fastened member, and a second member fastened to the fastened member together with the first member when the fastening member is threadedly engaged with the fastened member, the second member including a portion made of a first material and a portion made of a second material different from the first material, the fastening member being made of the second material, a difference between the effective fastening length of the portion of the second member made of the second material in the direction in which the fastening member is screwed onto the fastened members and the effective fastening length of the portion of the fastening member made of the second material when the fastener is fastened to the fastened members is equal to or less than a predetermined threshold value; and a difference between the effective fastening length of the first member in the direction in which the fastening member is screwed onto the fastened members and the effective fastening length of the portion of the second member made of the first material when the fastener is fastened to the fastened members is equal to or less than the predetermined threshold value. the law of nature , The threshold is an error tolerance. It is characterized by: [Effects of the Invention]

[0012] According to the present invention, for example, it is possible to provide a fastening structure that can reduce the problem of loosening or breakage due to temperature changes. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a cross-sectional view illustrating a fastening structure according to a first embodiment. [Figure 2] 4 is a cross-sectional view illustrating a temperature change in the fastening structure of the first embodiment. FIG. [Figure 3] FIG. 10 is a cross-sectional view illustrating a fastening structure according to a second embodiment. [Figure 4] FIG. 10 is a cross-sectional view illustrating a fastening structure according to a third embodiment. [Figure 5] FIG. 10 is a cross-sectional view illustrating a fastening structure according to a fourth embodiment. [Figure 6] FIG. 10 is a cross-sectional view illustrating a fastening structure according to a fifth embodiment. [Figure 7] FIG. 10 is a cross-sectional view illustrating a fastening structure according to a sixth embodiment. [Figure 8] FIG. 1 is a diagram showing an example of a conventional fastening structure that keeps a constant bolt axial force. [Figure 9] FIG. 13 is a cross-sectional view illustrating a fastening structure according to a seventh embodiment. [Figure 10] FIG. 1 is a conceptual diagram of a satellite optical system. [Figure 11] FIG. 1 is a schematic diagram illustrating a method for manufacturing an article. DETAILED DESCRIPTION OF THE INVENTION

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. In the following examples and drawings, redundant explanations will be omitted or simplified.

[0015] Example 1 A fastening structure according to a first embodiment, which prevents the fastening force of a bolt from increasing or decreasing with temperature changes and reduces the risk of loosening or breakage, will be described below with reference to FIG. 1. FIG. 1 is a cross-sectional view illustrating the fastening structure according to the first embodiment, taken along a line parallel to the central axis of a bolt 31. Note that the materials described in the first embodiment are merely examples, and any common structural material, such as iron, aluminum, copper, stainless steel, other metals or alloys, ceramics, or composite materials, may be used. Similar effects can also be achieved by substituting other materials. Hereinafter, the axial direction of a bolt 31 (described later) is referred to as the Z-axis direction (Z-direction), and two directions perpendicular to each other in a plane perpendicular to the Z-axis direction are referred to as the X-axis direction (X-direction) and the Y-axis direction (Y-direction). Furthermore, the direction in which the bolt 31 is threaded into the base material 1 or the nut 11 is referred to as the −Z direction, and the opposite direction is referred to as the +Z direction.

[0016] In the fastening structure of Example 1, components are fastened together using bolts, which are widely used due to their advantages such as ease of fastening, high fastening force, manageability of fastening force, ability to attach / detach and fine-adjust, and compact size. Unlike welding or adhesive bonding, bolt fastening does not limit the materials of the components, and it is easy to fasten dissimilar materials such as aluminum and steel, or ceramics and metals. In addition, the high fastening force of bolts is effective for fastening heavy objects and structures that are subjected to high forces. Bolted fastening is performed by the axial force generated by tightening the bolt threads, and under typical conditions, for example, a single M10 bolt generates an axial force of approximately 12 kN.

[0017] Another advantage of bolt tightening is that it is possible to control the axial force. One well-known method for controlling the axial force is to use a torque wrench. Another method is to determine the axial force from the elongation of the bolt when it is tightened, and there are also axial force meters that determine the axial force by measuring the change in length of the bolt when it is tightened using ultrasound.

[0018] The advantage of being able to control the axial force in fastening is that it enables highly accurate positioning and adjustment of parts, and it can prevent breakage due to excessive axial force when fastening brittle materials such as glass and ceramics. Bolt fastening, which allows for control of axial force, is an extremely useful fastening method for optical precision equipment that uses brittle materials such as glass.

[0019] Next, we will discuss the issues with fastening structures made of dissimilar materials, such as fastening aluminum materials with steel bolts or fastening ceramic materials with steel bolts. For example, aluminum is widely used in optical systems, various devices, and machinery to reduce weight. When fastening aluminum plates to frames, steel bolts are generally used, as they have high tensile strength and are easy to process and highly reliable in the threaded parts. However, when the temperature drops after the bolts are fastened, the aluminum plate, which has a higher linear expansion coefficient than steel, shrinks more, reducing the axial force of the bolts, which can cause changes in the highly accurate positional relationship or the bolts to loosen.

[0020] Like the aluminum material mentioned above, lightweight, highly rigid ceramics can be used in, for example, optical systems, various devices, machines, etc. When ceramics are fastened to a base material with iron bolts, if the temperature drops after fastening the bolts, the iron bolts, which have a higher linear expansion coefficient than the ceramics, will shrink more, increasing the axial force of the bolts and creating a risk of damaging the ceramics.

[0021] Consider, for example, the use of M10 bolts when fastening aluminum material to a frame or similar. In this case, if the initial axial force of the M10 bolt is 12 kN, a temperature drop of 20°C will reduce the axial force of the bolt to 9.5 kN. As such, the axial force of the bolt will decrease to approximately 79% with a temperature change of -20°C, and to approximately 58% with a temperature change of -40°C. Conversely, with an increase in temperature, the axial force will increase to approximately 121% with a temperature change of +20°C, and to approximately 142% with a temperature change of +40°C. In other words, even with bolt fastening, when connecting dissimilar materials and in an environment where there are temperature changes, there is a risk that precision cannot be maintained or that the bolt may break.

[0022] The fastening structure of Example 1 is a structure in which a fastened member (first member) 2, which is placed on a predetermined surface of a base material (fastened member) 1, is fastened to the base material 1 using a fastener 3 composed of multiple members. The fastener 3 of Example 1 is composed of a bolt (fastening member) 31 and an auxiliary member (second member) 32. Note that in Example 1, the fastened member 2 may also be included in the fastener 3. The auxiliary member 32 is further composed of a stepped washer 321 and a washer 322.

[0023] The fastened member 2 is a member to be fastened to the base material 1 by the fastener 3, and the fastened member 2 in Example 1 is made of an aluminum material (first material).

[0024] The bolt 31 is integrally formed with the head and male threaded portion connected in that order in the axial direction. In Example 1, the base material 1 is provided with a hole portion having a female threaded portion that can be threaded with the male threaded portion of the bolt 31. Then, by threading the male threaded portion of the bolt 31 into the female threaded portion of the base material 1, the fastened member 2 and the auxiliary member 32 can be fastened to the base material 1. The bolt 31 in Example 1 is made of an iron material (second material).

[0025] The stepped washer 321 has two flanges, one above the other. As shown in FIG. 1, the stepped washer 321 is formed in a so-called hat shape, with one end of one flange and the other end of the other flange joined to a connecting member formed with a predetermined length in the Z direction. When the workpiece 2 is fastened to the base material 1 using a fastener, the lower surface of one flange abuts against the upper surface of the washer 322, and the upper surface of the other flange abuts against the lower surface of the head of the bolt 31, and the lower surface of the flange abuts against a predetermined surface of the base material 1. The stepped washer 321 in Example 1 is made of aluminum.

[0026] The stepped washer 321 has at least one through hole at a position where the male thread portion of the bolt 31 is inserted. The through hole is formed with a diameter larger than the diameter of the male thread portion of the bolt 31. Alternatively, the through hole may have the same diameter as the male thread portion and may be threaded so as to be able to be screwed onto the male thread portion.

[0027] Washer 322 is formed in a circular or polygonal shape with a predetermined thickness, and a through-hole is formed in the center of washer 322. The through-hole is formed with a diameter larger than the outer diameter of the connecting member of stepped washer 321. Washer 322 in Example 1 is made of an iron material.

[0028] In Example 1, as described above, the fastened members 2 are made of aluminum, which is the first material. Furthermore, the stepped washer 321 is also made of aluminum, which is the first material, like the fastened members 2. Furthermore, in Example 1, the bolt 31 is made of iron, which is the second material. Furthermore, the washer 322 is also made of iron, which is the second material, like the bolt 31. Furthermore, the stepped washer 321 and the washer 322 are each made separately, but the auxiliary member 32 may be configured to include an integral portion having a portion made of aluminum and a portion made of iron. Note that even in this configuration, the stepped washer 321 and the washer 322 may each be configured to be separable.

[0029] In Example 1, the material of the base material 1 may be any of general structural materials such as iron, aluminum, copper, stainless steel, other metals or alloys, ceramics, composite materials, etc. This is because the material of the base material 1 does not affect the effect of Example 1.

[0030] The fastened member 2 is fastened to the base material 1 by the bolt 31 via the washer 322 and the stepped washer 321. The direction of the central axis (Z direction) of the bolt 31, that is, the direction in which the bolt 31 is screwed into the base material 1, is defined as the fastening direction of the bolt 31. The relationship of the dimensions of each part in the fastening structure of Example 1 with respect to this fastening direction will be explained below. Hereinafter, the dimensions of the part where the fastening axial force of the bolt 31 acts in the fastening direction of the bolt 31 of Example 1 are defined as the effective fastening dimensions.

[0031] In addition, in this structure, expansion and contraction due to temperature changes in directions perpendicular to the bolt fastening axis (X direction, Y direction) can be ignored because it has almost no effect on the tightening force (fastening force) of the bolt 31. Therefore, in Example 1, the following temperature change assumptions are based only on expansion and contraction of the bolt 31 in the fastening axis direction (Z direction).

[0032] The dimensions effective for fastening the workpieces 2 are the area indicated by A2 in Fig. 1. The dimensions effective for fastening the bolt 31 are the area indicated by B31 in Fig. 1. The dimensions effective for fastening the stepped washer 321 are the area indicated by A321 in Fig. 1. The dimensions effective for fastening the washer 322 are the area indicated by B322 in Fig. 1.

[0033] The relationship between the dimensions of each member is expressed by the following formulas (1) and (2). (Number 1) A2=A321 (1) B322=B31 (2) That is, the length A2 that is effective for fastening the workpiece 2 in the direction in which the bolt 31 is screwed into the base material 1 matches the length A321 that is effective for fastening the stepped washer 321 when the fastener 3 is fastened to the base material 1. Note that these lengths do not have to match, as long as the difference in length between A2 and A321 is equal to or less than a predetermined threshold value.

[0034] Furthermore, the length B322 effective for fastening the washer 322 in the direction in which the bolt 31 is screwed into the base material 1 matches the length B31 effective for fastening the bolt 31 when the fastener 3 is fastened to the base material 1. Note that these lengths do not have to match, as long as the difference between the lengths B322 and B31 is equal to or less than a predetermined threshold. Note that the predetermined threshold is the allowable value for processing errors (tolerances) in the manufacture of each member used in the fastening structure of Example 1.

[0035] The relationship between the temperature changes of the fastened members 2 and the fastener 3 shown in Example 1 when a temperature change occurs in each of them will be described below with reference to Figure 2. Figure 2 is a cross-sectional view illustrating temperature changes in the fastening structure of Example 1. In Figure 2, the amount of temperature change is ΔT, the linear expansion coefficient of the aluminum material of the fastened members 2 is α2, and the linear expansion coefficient of the iron material of the bolt 31 is α31. Here, the dimensional change (change in distance) in the direction effective for fastening the fastened members 2 is expressed by the following equation (3). (Number 2) A2×α2×ΔT=A2' (3)

[0036] The dimensional change in the direction effective for fastening the bolt 31 is expressed by the following formula (4). (Number 3) B31×α31×ΔT=B31' (4)

[0037] The dimensional change in the direction effective for fastening the stepped washer 321 is expressed by the following formula (5) because the linear expansion coefficient of the stepped washer 321 is the same as the linear expansion coefficient for fastening the fastened members 2. (Number 4) A321×α2×ΔT=A321' (5) Then, the following equation (6) can be derived from the relationship in equation (1) above. (Number 5) A2'= A321' (6) According to the above formula (6), when a temperature change of ΔT occurs, the dimensional change of the fastened workpiece 2 and the dimensional change of the stepped washer 321 coincide with each other.

[0038] The dimensional change in the direction effective for fastening the washer 322 is expressed by the following formula (7) because the linear expansion coefficient of the washer 322 is the same as the linear expansion coefficient for fastening the bolt 31. (Number 6) B322×α31×ΔT=B322' (7) Then, from the relationship in the above formula (2), the following formula (8) can be derived.

[0039] (Number 7) B322'=B31' (8) According to the above formula (8), when a temperature change of ΔT occurs, the dimensional change of bolt 31 and the dimensional change of washer 322 coincide with each other.

[0040] Next, by adding up the dimensional relationships of each component based on the contact surface between the fastened component 2 and the base material 1, the following formula (9) can be derived. (Number 8) A2+B322-A321-B31=0 (9) Furthermore, from the relationship between the above formulas (6) and (8), the following formula (10) can be derived by modifying the above formula (9).

[0041] (Number 9) A2'+B322'-A321'-B31'=0 (10) According to the above formula (10), even if a temperature change of ΔT occurs, the dimensional changes of each part are offset, so the fastening force of the fastener 3 does not change.

[0042] As described above, in the fastening structure of Example 1, the expansion and contraction of the fastened members 2 and the fastener 3 due to temperature changes are offset by the corresponding members, so the fastening force does not change even when temperature changes occur. Furthermore, because the expansion and contraction offsetting action is performed on the same material, it is not affected by the magnitude of the material's linear expansion coefficient or temperature dependency. Therefore, this effect can be maintained from absolute zero to the melting point of the material. Therefore, it is possible to provide a fastening structure that can reduce the problems of loosening and breakage of the fastened members and fasteners due to temperature changes.

[0043] <Example 2> In the fastening structure of Example 2, a fastened member (first member) 2 placed on a predetermined surface of a fastened member 21 is fastened using a fastener 3 and a nut 11. The fastener 3 is composed of a bolt (fastening member) 31 made of an iron-based material and an auxiliary member (second member) 32, and may include the fastened member 2. The auxiliary member 32 is composed of a stepped washer 321 made of an aluminum material and a washer 322 made of an iron material. The fastening structure of Example 2 will be described below with reference to FIG. 3. FIG. 3 is a cross-sectional view illustrating the fastening structure of Example 2, taken parallel to the central axis of the bolt 31.

[0044] In Example 2, the material of the nut 11 can be any of general structural materials such as iron, aluminum, copper, other metals or alloys, ceramics, composite materials, etc., without affecting the effect. Therefore, no particular mention will be made here of the material of the nut 11. In addition, the nut 11 has a female thread portion that can be threaded onto the male thread portion of the bolt 31.

[0045] In Example 2, fastened members 2 placed on a predetermined surface of fastened members 21 are fastened using a bolt 31 and a nut 11 via a washer 322 and a stepped washer 321. Note that the configuration and materials of the fastener 3 are the same as those in Example 1, and therefore overlapping descriptions will be omitted. In Example 2, as shown in FIG. 3 , fastened members 21 are placed on the surface opposite the predetermined surface of fastened members 2. The predetermined surface of fastened members 2 and the predetermined surface of fastened members 21 abut against each other. In Example 2, fastened members 2 and an auxiliary member 32 can be fastened to fastened members 21 by threading bolt 31 of fastener 3 into nut 11. When fastened, the predetermined surface of nut 11 abuts against the surface of fastened members 21 opposite the predetermined surface.

[0046] The dimensional relationships effective for fastening in Example 2 are described below. Fastened members 2 and 21 are made of the same aluminum material. The dimension effective for fastening fastened members 2 and 21 is dimension A21 when the two fastened members 2 and 21 are stacked together, as shown in Figure 3. The dimension effective for fastening bolt 31 is the portion indicated by B31 in Figure 3. The dimension effective for fastening stepped washer 321 is the portion indicated by A321 in Figure 3. The dimension effective for fastening washer 322 is the portion indicated by B322 in Figure 3.

[0047] The relationship between the dimensions of each member is shown in the following formulas (11) and (12). (Number 10) A21=A321 (11) B322=B31 (12) That is, the length A21 that is effective for fastening the workpieces 2 and 21 in the direction in which the bolt 31 is screwed into the nut 11 matches the length A321 that is effective for fastening the stepped washer 321 when the fastener 3 is fastened to the workpieces 21. Note that these lengths do not have to match, as long as the difference between the lengths A21 and A321 is equal to or less than a predetermined threshold.

[0048] Furthermore, the length B322 effective for fastening the washer 322 in the direction in which the bolt 31 is threaded onto the nut 11 is the same as the length B31 effective for fastening the bolt 31 when the fastener 3 is fastened to the fastened member 21. Note that these lengths do not have to be the same, as long as the difference between the lengths B322 and B31 is equal to or less than a predetermined threshold. Note that the predetermined threshold is the allowable value for the processing error of each member used in the fastening structure of Example 2. Furthermore, when the bolt 31 is threaded onto the nut 11, the fastened member 21 is interposed therebetween.

[0049] Here, by substituting the dimension A2 in the first embodiment with A21 and modifying the above equation (9), the following equation (13) can be derived. A21+B322-A321-B31=0 (13) In the above formula (13), as in the above formula (10), even if a temperature change of ΔT occurs, the dimensional changes of the components are offset, so the fastening force of the fastener 3 does not change.

[0050] As described above, the fastening structure of the second embodiment can provide a fastening structure that can reduce the problems of loosening and breakage of fastened members and fasteners due to temperature changes, similar to the first embodiment.

[0051] Example 3 In the fastening structure of Example 3, the two fastened members, fastened member 22 and fastened member 23, are made of different materials. The fastening structure of Example 3 will be described below with reference to Fig. 4. Fig. 4 is a cross-sectional view illustrating the fastening structure of Example 3, taken along a line parallel to the central axis of bolt 31. Note that descriptions of parts and configurations that are the same as those in the above examples will be omitted.

[0052] The fastening structure in Example 3 is a structure in which a fastened member 22 made of an aluminum material, which is placed on a predetermined surface of a fastened member 23 made of a copper material, is fastened using a fastener 3 and a nut 11. The fastener 3 is composed of a bolt (fastening member) 31 made of an iron-based material and an auxiliary member (second member) 32. The auxiliary member 32 is composed of a stepped washer 321 made of an aluminum material, a stepped washer 321 made of copper material, and washers 322 and 324 made of iron. In Example 3, the fastened member 22 and the fastened member 23 abut on their predetermined surfaces. The abutting surface between the fastened member 22 and the fastened member 23 is defined as an interface, with a predetermined direction relative to the interface defined as the upper direction and the opposite direction defined as the lower direction. The upper direction and the lower direction can each be considered to be independently similar to the configuration of Example 1. In this case, the upper side is the +Z direction side from the interface of the workpiece 22, and the lower side is the −Z direction side when viewed from a predetermined surface of the workpiece 22.

[0053] The relationship between the dimensions of each part and the parts effective for fastening will be described below with reference to Example 1. Because fastened members 22 are made of aluminum, the dimensions effective for fastening fastened members 22 are the portion shown by A22 in FIG. 4, which corresponds to A2 in Example 1. For bolt 31, the dimensions effective for fastening the upper side from the interface between two fastened members 22, 23 are the portion shown by B311 in FIG. 4, which corresponds to B31 in Example 1. Because stepped washer 321 is made of the same aluminum material as fastened members 22, the dimensions effective for fastening stepped washer 321 are the portion shown by A321 in FIG. 4, which corresponds to A321 in Example 1. Because washer 322 is made of the same iron material as bolt 31, the dimensions effective for fastening washer 322 are the portion shown by B322 in FIG. 4, which corresponds to B322 in Example 1.

[0054] Furthermore, because fastened members 23 are made of copper, the dimensions effective for fastening fastened members 23 are the portion shown by A23 in FIG. 4, which corresponds to A2 in Example 1. Because bolt 31 is made of iron, the dimensions effective for fastening bolt 31 below the interface between two fastened members 22, 23 are the portion shown by B312 in FIG. 4, which corresponds to B31 in Example 1. Because stepped washer 323 is made of the same copper material as fastened members 23, the dimensions effective for fastening stepped washer 323 are the portion shown by A323 in FIG. 4, which corresponds to A321 in Example 1. Because washer 324 is made of the same iron material as bolt 31, the dimensions effective for fastening washer 324 are the portion shown by B324 in FIG. 4, which corresponds to B322 in Example 1.

[0055] The relationship between the dimensions of each member above the interface between the two fastened members is expressed by the following formulas (14) and (15). (Number 11) A22=A321 (14) B322=B311 (15) That is, the length A22 effective for fastening the workpiece 22 in the direction in which the bolt 31 is screwed into the nut 11 matches the length A321 effective for fastening the stepped washer 321 when the fastener 3 is fastened to the workpiece 23. Note that these lengths do not have to match, as long as the difference between the lengths A22 and A321 is equal to or less than a predetermined threshold.

[0056] Furthermore, the length B322 effective for fastening the washer 322 in the direction in which the bolt 31 is threaded into the nut 11 matches the length B311 effective for fastening the upper side from the interface between the two fastened members 22, 23 when the fastener 3 is fastened to the fastened members 23. Note that these lengths do not have to match, as long as the difference in length between B322 and B311 is equal to or less than a predetermined threshold. Note that the predetermined threshold is the allowable value for processing error of each member used in the fastening structure of Example 3.

[0057] Furthermore, below the interface between the two fastened members, the following equations (16) and (17) are given: (Number 12) A23=A323 (16) B324=B312 (17) That is, the length A23 effective for fastening the workpiece 23 in the direction in which the bolt 31 is screwed into the nut 11 matches the length A323 effective for fastening the stepped washer 323 when the fastener 3 is fastened to the workpiece 23. Note that these lengths do not have to match, and it is sufficient that the difference between the lengths A23 and A323 is equal to or less than a predetermined threshold.

[0058] Furthermore, the length B324 effective for fastening the washer 324 in the direction in which the bolt 31 is threaded into the nut 11 is the same as the length B312 effective for fastening the lower side of the interface between the two fastened members 22, 23 when the fastener 3 is fastened to the fastened members 23. Note that these lengths do not have to be the same, as long as the difference between the lengths B324 and B312 is equal to or less than a predetermined threshold. Note that the predetermined threshold is the allowable value for processing error of each member used in the fastening structure of Example 3. Furthermore, when the bolt 31 is threaded into the nut 11, the fastened member 23 is interposed therebetween.

[0059] In this way, the relationships of the above formulas (9) and (10) shown in Example 1 can be satisfied on the upper and lower sides of the interface between the two fastened members 22 and 23. Therefore, even if a temperature change of ΔT occurs, the dimensional changes of each part are offset, so the fastening force of the fastener 3 does not change.

[0060] As described above, the fastening structure of the third embodiment can provide a fastening structure that can reduce the problems of loosening and breakage of fastened members and fasteners due to temperature changes, similar to the first embodiment.

[0061] Example 4 In the configuration of Example 2, the dimensions of washer 322 are large, which imposes dimensional constraints on implementation. To solve this problem, in the fastening structure of Example 4, washer 322 of the fastening structure of Example 2 is divided into two while maintaining the dimensions effective for fastening. This allows the larger dimension on one side to be allocated between a predetermined direction when viewed from the interface between the two fastened members 2 and 21 and a direction opposite to the predetermined direction (up and down). The fastening structure of Example 4 will be described below with reference to FIG. 5. FIG. 5 is a cross-sectional view illustrating the fastening structure of Example 4, which is parallel to the central axis of bolt 31. Note that Example 4 will be described with reference to the configuration of Example 2. Furthermore, descriptions of parts and configurations similar to those of the above-mentioned examples will be omitted.

[0062] In the fastening structure of Example 4, similarly to Example 2, a fastened member (first member) 2 placed on a predetermined surface of a fastened member 21 is fastened using a fastener 3 and a nut 11. The fastener 3 is composed of a bolt (fastening member) 31 made of an iron-based material and an auxiliary member (second member) 32, and may include the fastened member 2. The auxiliary member 32 is composed of a stepped washer 321 made of an aluminum material and washers 3221 and 3222 made of iron. The fastened members 2 and 21 are made of aluminum.

[0063] In Example 4, fastening of fastened members 2 placed on a predetermined surface of fastened members 21 is performed by bolt 31 via washer 3221 and stepped washer 321, and nut 11 via washer 3222. Then, by threading bolt 31 of fastener 3 into nut 11, fastened members 2 and auxiliary member 32 can be fastened to fastened members 21. When fastened, a predetermined surface of washer 3222 abuts against a surface of fastened members 21 opposite the predetermined surface, and a predetermined surface of nut 11 abuts against a surface of washer 3222 opposite the predetermined surface.

[0064] The dimensional relationships effective for fastening are described below. Because fastened members 2 and 21 are made of the same aluminum material, the effective dimension for fastening fastened members 2 and 21 is dimension A2 when the two fastened members 2 and 21 are stacked together, as shown in Figure 5. Because bolt 31 is made of iron, the effective dimension for fastening bolt 31 is the portion shown by B31 in Figure 5. Because stepped washer 321 is made of the same aluminum material as fastened members 2, the effective dimension for fastening stepped washer 321 is the portion shown by A321 in Figure 5. Because washer 3221 is made of the same iron material as bolt 31, the effective dimension for fastening washer 3221 is the portion shown by B3221 in Figure 5. Because washer 3222 is made of the same iron material as bolt 31, the effective dimension for fastening washer 3222 is the portion shown by B3222 in Figure 5.

[0065] The relationship between the dimensions of each member is expressed by the following formulas (18) and (19). (Number 13) A2=A321 (18) B3221+B3222=B31 (19) That is, the length A2 that is effective for fastening the workpiece 2 in the direction in which the bolt 31 is screwed into the nut 11 matches the length A321 that is effective for fastening the stepped washer 321 when the fastener 3 is fastened to the workpiece 21. Note that these lengths do not have to match, as long as the difference between A2 and A321 is equal to or less than a predetermined threshold value.

[0066] Furthermore, the total length B3211 and B3222, which are the lengths effective for fastening washers 3211 and 3222 in the direction in which bolt 31 is threaded onto nut 11, is the same as length B31, which is the length effective for fastening bolt 31 when fastener 3 is fastened to fastened member 21. Note that these lengths do not have to be the same, as long as the difference between the total length of B3211 and B3222 and B31 is equal to or less than a predetermined threshold. Note that the predetermined threshold is the allowable value for processing error of each member used in the fastening structure of Example 4. Furthermore, when bolt 31 is threaded onto nut 11, fastened member 21 is interposed therebetween.

[0067] Then, by adding up the dimensional relationships of each member based on the contact surface between the washer 3222 and the nut 11, the following formula (20) can be derived. (Number 14) A2+B3221+B3222-A321-B31=0 (20) According to the above formula (20), even if a temperature change of ΔT occurs, the dimensional changes of each part are offset from the above formula (18) and formula (19), just as in the above formula (10), and therefore the fastening force of the fastener 3 does not change.

[0068] As described above, the fastening structure of the fourth embodiment can provide a fastening structure that can reduce the problems of loosening and breakage of fastened members and fasteners due to temperature changes, similar to the first embodiment.

[0069] <Example 5> The fastening structure of Example 5 uses an integral bolt 311 formed by joining metals different from those of the bolt 31. The fastening structure of Example 5 will be described below with reference to Fig. 6. Fig. 6 is a cross-sectional view illustrating the fastening structure of Example 5, taken along a line parallel to the central axis of the integral bolt 311. Descriptions of parts and configurations that are the same as those in the above-described examples will be omitted.

[0070] The fastening structure of Example 5 is a structure in which a fastened member (first member) 2, which is placed on a predetermined surface of a base material (fastened member) 1, is fastened to the base material 1 using a fastener 3. The fastener 3 of Example 5 is composed of an integral bolt 311 formed by joining together different metals, and an auxiliary member (second member) 32. Note that in Example 5, the fastened member 2 may also be included in the fastener 3. The auxiliary member 32 of Example 5 is a washer 322 made of iron. The fastened member 2 is made of aluminum.

[0071] Here, the integral bolt 311 is composed of an integral bolt aluminum portion 3111 made of the same aluminum material as the fastened members 2, and an integral bolt iron portion 3112 made of iron material, and the integral bolt aluminum portion 3111 and the integral bolt iron portion 3112 are joined by fusion. The above joining method may also use other joining means such as adhesion or mechanical bonding.

[0072] The dimensional relationships effective for fastening each part are explained below. The dimensions are determined based on the joint surface between the integral bolt aluminum part 3111 and the integral bolt iron part 3112. The dimensions effective for fastening the fastened members 2 are located at the area indicated by A2 in Figure 6. The dimensions effective for fastening the integral bolt aluminum part 3111 are located at the area indicated by A3111 in Figure 6. The dimensions effective for fastening the integral bolt iron part 3112 are located at the area indicated by B3112 in Figure 6. The dimensions effective for fastening the washer 322 are located at the area indicated by B322 in Figure 6.

[0073] The relationship between the dimensions of each member is shown in the following equations (21) and (22). (Number 15) A2=A3111 (21) B322=B3112 (22) That is, the length A2 that is effective for fastening the workpieces 2 in the direction in which the integrated bolt 311 is screwed into the base material 1 matches the length A3111 that is effective for fastening the aluminum portion 3111 of the integrated bolt when the fastener 3 is fastened to the base material 1. Note that these lengths do not have to match, and it is sufficient if the difference in length between A2 and A3111 is equal to or less than a predetermined threshold value.

[0074] Furthermore, the length B322 effective for fastening the washer 322 in the direction in which the integrated bolt 311 is screwed into the base material 1 is the same as the length B3112 effective for fastening the integrated bolt / iron part 3112 when the fastener 3 is fastened to the base material 1. Note that these lengths do not have to be the same, as long as the difference in length between B322 and B3112 is equal to or less than a predetermined threshold value. Note that the predetermined threshold value is the allowable value for processing error of each member used in the fastening structure of Example 5.

[0075] According to the above formulas (21) and (22), as with formula (10) shown in the first embodiment, even if a temperature change of ΔT occurs, the dimensional changes of the components are offset, and therefore the fastening force of the integral bolt 311 does not change.

[0076] As described above, the fastening structure of the fifth embodiment can provide a fastening structure that can reduce the problems of loosening and breakage of fastened members and fasteners due to temperature changes, similar to the first embodiment.

[0077] Example 6 In the fastening structure of Example 6, a fastened member (first member) 2 placed on a predetermined surface of a fastened member 21 is fastened using a fastener 3 and a nut 11. The fastening structure of Example 6 will be described below with reference to FIG. 7. FIG. 7 is a cross-sectional view illustrating the fastening structure of Example 6, which is a cross-sectional view parallel to the central axis of an integrated bolt 311. Furthermore, descriptions of parts and configurations that are the same as those in the above-mentioned examples will be omitted.

[0078] The fastener 3 of Example 6 is composed of an integral bolt 311 formed by joining together dissimilar metals similar to Example 5, and an auxiliary member (second member) 32. In Example 6, the fastened members 2 may also be included in the fastener 3. The auxiliary member 32 of Example 6 is a washer 322 made of iron. The fastened members 2 and 21 are each made of aluminum.

[0079] As in Example 5, the integral bolt 311 comprises an integral-bolt aluminum portion 3111 made of the same aluminum material as the fastened members 2, and an integral-bolt iron portion 3112 made of iron material. The integral-bolt aluminum portion 3111 and the integral-bolt iron portion 3112 are joined by fusion.

[0080] The dimensional relationships effective for fastening each part are explained below. Since fastened members 2 and 21 are made of the same aluminum material, the dimension effective for fastening fastened members 2 and 21 is dimension A21 when fastened members 2 and 21 are stacked as shown in Figure 7. As with Example 5, the dimensions are determined based on the joint surface between integral bolt-aluminum portion 3111 and integral bolt-iron portion 3112. The dimension effective for fastening integral bolt-aluminum portion 3111 is the portion indicated by A3111 in Figure 6. The dimension effective for fastening integral bolt-iron portion 3112 is the portion indicated by B3112 in Figure 6. The dimension effective for fastening washer 322 is the portion indicated by B322 in Figure 6.

[0081] The relationship between the dimensions of each member is shown in the following equations (23) and (24). (Number 16) A21=A3111 (23) B322=B3112 (24) That is, the length A21 that is effective for fastening the workpieces 2 and 21 in the direction in which the integrated bolt 311 is screwed into the nut 11 matches the length A3111 that is effective for fastening the integrated bolt aluminum portion 3111 when the fastener 3 is fastened to the workpieces 21. Note that these lengths do not have to match, as long as the difference in length between A21 and A3111 is equal to or less than a predetermined threshold value.

[0082] Furthermore, the length B322 effective for fastening the washer 322 in the direction in which the integral bolt 311 is screwed into the nut 11 is the same as the length B3112 effective for fastening the integral bolt iron portion 3112 when the fastener 3 is fastened to the fastened member 21. Note that these lengths do not have to be the same, as long as the difference in length between B322 and B3112 is equal to or less than a predetermined threshold value. Note that the predetermined threshold value is the allowable value for the processing error of each member used in the fastening structure of Example 6. Furthermore, when the integral bolt 311 is screwed into the nut 11, a fastened member 23 is interposed therebetween.

[0083] According to the above formulas (23) and (24), even if a temperature change of ΔT occurs, the dimensional changes of the components are offset, as in the case of formula (10) shown in the first embodiment, and therefore the fastening force of the integral bolt 311 does not change.

[0084] As described above, the fastening structure of the sixth embodiment can provide a fastening structure that can reduce the problems of loosening and breakage of fastened members and fasteners due to temperature changes, similar to the first embodiment.

[0085] Example 7 In Example 7, the fastening structure of Example 1 is applied to a molding apparatus, such as an imprinting apparatus (lithography apparatus) or a planarization processing apparatus, for molding a composition on a substrate. The imprinting apparatus is an apparatus that forms a pattern of a composition on a substrate by irradiating (exposing) light to a composition (imprinting material) supplied onto a substrate using a mold (die) having a concave-convex pattern, and curing the composition. The planarization apparatus is an apparatus that flattens the surface of the composition by contacting a mold (template) having a planar shape with the composition on the substrate. The fastening structure of Example 7 will be described below with reference to FIG. 9. FIG. 9 is a cross-sectional view illustrating the fastening structure of Example 7. Furthermore, FIG. 9 shows a cross section connecting the centers of two bolts 31 that fasten a lens holding flange 24. Furthermore, descriptions of parts and configurations that are the same as those in the above examples will be omitted.

[0086] Similar to Example 1, bolt fastening is also used in molding devices that are exposed to high temperatures and require highly accurate positioning of components and suppression of component deformation. For example, in an imprinting device, to cure a composition on a substrate, high-intensity light such as ultraviolet light (e.g., laser light) is irradiated from an irradiation unit (illumination unit) (not shown) onto the composition through a mold having a concave-convex pattern. The irradiation unit (not shown) includes, for example, a light source and an optical system (illumination optical system) for adjusting the light emitted from the light source to an optimal light intensity for curing the composition to a desired hardness. The optical system may include optical elements such as lenses, an aperture (opening), a shutter for switching between irradiation and blocking, and the like.

[0087] The optical system heats up due to the energy of the irradiated light. In particular, components such as illumination optical systems can heat up to several hundred degrees Celsius. To minimize deterioration of the shape and positional relationship of the optical system and optical elements at such high temperatures, various component parts and their arrangement methods have been devised. However, fastening components made of different materials is unavoidable, and the temperature changes described above can cause minute deformations and component damage. Furthermore, the fastening structure of Example 1 can be applied not only to the molding device described above, but also to an interchangeable lens (optical device) having an optical system equipped with a lens, which is an optical element. In this case, the fastening structure of Example 1 can be applied when fastening the optical system to other components. It can also be applied to various devices that use bolt fastening, such as semiconductor exposure devices and transport devices.

[0088] In the fastening structure of Example 7, a lens holding flange 24 that is disposed on a predetermined surface of a base material (base) 1 and holds an optical element is fastened to the base material 1 using a fastener 3. The configuration of the fastener 3 of Example 7 is the same as that of Example 1.

[0089] A lens (optical element) is inserted into the center of the lens holding flange 24 and is held in an optical positional relationship with another lens (not shown). The lens holding flange 24 heats up as it focuses high-power light. This temperature rise can cause the lens holding flange 24, its surroundings, and components such as the fastener 3 to reach temperatures of approximately 200°C. As an example, the bolt 31 shown in FIG. 9 is an M5 hexagon socket head bolt (chromium molybdenum steel: SCM435). The bolt 31 is initially fastened at room temperature with an axial force of 10,000 N. The lens holding flange 24 is made of aluminum (5000 series aluminum: A5052). Various physical properties are shown in Table 1 below.

[0090] [Table 1]

[0091] According to Table 1 above, similar to Example 1, the material and dimensions of the stepped washer 321 are the same as those of the lens holding flange 24, and the material and dimensions of the washer 322 are also the same as those of the bolt 31.

[0092] Assume that the lens holding flange 24 is heated by the light irradiated from the irradiation unit of the molding device in Example 7, and the temperature rises to, for example, 200° C. Even in this case, as in Example 1, the expansion and contraction of the lens holding flange 24 and the fastener 3 due to temperature changes can be offset by the corresponding members, so the initial axial force of 10,000 [N] of the bolt 31 remains unchanged.

[0093] As described above, in the fastening structure of Example 7, by using the fastening structure of Example 1 to fasten an optical system or other components in a device such as a molding device, it is possible to reduce the problem of loosening or breakage of the fastened components or fasteners due to temperature changes, as in Example 1.

[0094] As in Example 1, each member used in the fastening structure should have a tolerance for processing error, but in reality, there may be errors in the dimensions effective for fastening the lens holding flange 24, bolt 31, stepped washer dimension A321, and washer A322. An example of a change in axial force caused by such dimensional errors is shown below.

[0095] As an example, consider a case where the effective fastening dimension of stepped washer 321 was assumed to be a maximum of 4 mm due to the tolerance for processing error, but was 1 mm longer, or 5 mm, due to processing during manufacturing. In this case, when bolt 31 is tightened, the effective fastening dimension shortens from 6 mm to 5 mm. If the temperature rises from this state (initial state) to 200°C as described above, for example, the bolt axial force will decrease by approximately 2000 N. Therefore, when the initial axial force is 100,000 N, the bolt axial force will decrease by 20%.

[0096] A decrease in the fastening force of the lens holding flange 24 by approximately 10% raises concerns about misalignment of the lens holding flange 24 or any of the fastening members. Furthermore, misalignment or deformation of the lens holding flange 24 may also cause deformation or misalignment of the optical element, degrading the performance of the device in Example 7. For this reason, taking into consideration cases where the allowable values ​​for temperature changes and processing errors are exceeded, it is preferable to keep the fluctuation in the bolt axial force to 1% or less.

[0097] For example, assume an environment with a temperature change of 200°C, as in the example above. In this case, if the variation in bolt axial tension is to be kept to 1% or less, it is desirable that the error in the dimensions effective for fastening the lens holding flange 24, bolt 31, stepped washer 321, and washer 322 be 0.05 mm or less. In this case, processing errors (tolerances) should be taken into consideration. Note that the variation in bolt axial tension described above is not limited to Example 7, and applies similarly to each of the above examples.

[0098] Additionally, because differences (errors) in the linear expansion coefficients of materials can also cause axial force fluctuations, it is preferable to match the linear expansion coefficients of corresponding components. However, due to design constraints, it is possible to use SMC440 for the bolt material strength classification, even though it is made of the same carbon steel as washer 322. For example, if the bolt 31 is made of SCM440 (linear expansion coefficient: 12.5 ppm) with the dimensions shown in Table 1 above, the axial force will increase by 1,208 N at 200°C, a 12% increase from the initial axial force of 100,000 N. Therefore, to keep the bolt axial force fluctuations to 1% or less, it is desirable for the difference in the linear expansion coefficients of the lens retaining flange 24 and stepped washer 321, or bolt 31 and washer 322, which are made of the same material, to be 0.12 ppm or less. In other words, as long as the difference in linear expansion coefficients is within the desired value, the material type, steel grade number (JIS standard, etc.), or composition may be different.

[0099] Example 8 In Example 8, the fastening structure of Example 1 is applied to a satellite optical system. Fig. 10 is a conceptual diagram of a satellite optical system 6 that focuses light rays incident from the right side when viewed from the front of Fig. 10. Furthermore, explanations of parts and configurations that are the same as those in the above examples will be omitted.

[0100] Bolted fastening is useful for precision optical equipment mounted on satellites, and is an advantageous fastening method that can withstand the large vibrations and accelerations that occur during satellite launch and satisfy the high mounting precision of the components that make up the optical system. However, even in bolted fastening, if the bolt and the fastened parts are made of different materials, the axial force will change due to the large temperature difference in space, creating the risk of loosening the fastener or damaging the parts. The range of temperature changes in space is large, with a temperature difference of more than 100°C occurring between when exposed to sunlight and when in the shade.

[0101] Therefore, similarly to Example 7, by using the fastening structure of Example 1 to fasten optical elements of a satellite optical system, it is possible to suppress performance degradation of the optical system, which is affected by temperature changes from high to extremely low temperatures, and reduce the risk of damage.

[0102] The optical element 61 is precisely positioned with respect to the incident light and is arranged to minimize the effect of changes in the mirror shape due to temperature changes. As with the example described above, with typical bolt fastening, a temperature change of 100°C causes a 10% change in axial force, and minute deformations in the flange due to a 100°C drop in temperature result in misalignment and deformation of the optical element, which is a factor in degrading optical performance. Therefore, by using the fastening structure of Example 1, the axial force does not change, making it possible to reduce the effects of stress on the optical element and minute misalignment in the optical element position, which are factors in degrading optical performance.

[0103] As described above, in the fastening structure of Example 8, by using the fastening structure of Example 1 to fasten the optical system of the satellite optical system or other components, it is possible to provide a fastening structure that can reduce the risk of loosening or breakage of fasteners due to temperature changes from high temperatures to extremely low temperatures.

[0104] <Example of article manufacturing method> The pattern of the cured product formed using the molding device is used permanently on at least a portion of various articles, or temporarily when manufacturing various articles. Examples of articles include electrical circuit elements, optical elements, MEMS, recording elements, sensors, and molds. Examples of electrical circuit elements include volatile or nonvolatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, and semiconductor elements such as LSI, CCD, image sensors, and FPGA. Examples of molds include molds for imprinting.

[0105] The pattern of the cured product may be used as it is as at least a part of a component of the article, or may be used temporarily as a resist mask, which is removed after etching or ion implantation in a substrate processing step.

[0106] Next, a specific method for manufacturing an article will be described with reference to FIG. 11. The molding apparatus shown in FIG. 11 is an imprinting apparatus, which is one type of molding apparatus, and the molding apparatus has the fastening structure shown in the above-described embodiment for fastening an optical system to other components. As shown in FIG. 11(A), a substrate 1z such as a silicon wafer having a workpiece 2z such as an insulator molded on its surface is prepared, and then an imprinting material (photocurable material) 3z is applied to the surface of the workpiece 2z by an inkjet method or the like. Here, the imprinting material 3z in the form of multiple droplets is shown applied to the substrate.

[0107] As shown in Figure 11(B), the imprinting mold 4z is placed facing the imprinting material 3z on the substrate, with the side on which the concave-convex pattern is formed. As shown in Figure 11(C), the substrate 1z to which the imprinting material 3z has been applied is brought into contact with the mold 4z, and pressure is applied (contact process). The imprinting material 3z fills the gap between the mold 4z and the workpiece 2z. In this state, light is irradiated through the mold 4z as hardening energy, causing the imprinting material 3z to harden (hardening process).

[0108] 11(D), after the imprint material 3z is cured, the mold 4z and the substrate 1z are separated, and a pattern of the cured imprint material 3z is formed on the substrate 1z (pattern forming process). In this cured material pattern, the recesses of the mold correspond to the protrusions of the cured material, and vice versa. In other words, the recessed and protrusion pattern of the mold 4z is transferred to the imprint material 3z.

[0109] As shown in Figure 11(E), etching is performed using the cured material pattern as an etching-resistant mask, and the portions of the surface of the workpiece 2z where no cured material or only a thin layer remains are removed, forming grooves 5z (processing step). As shown in Figure 11(F), removing the cured material pattern results in an article with grooves 5z formed in the surface of the workpiece 2z. Here, the cured material pattern is removed, but it may also be used as an interlayer insulating film included in a semiconductor device or the like, i.e., a component of an article, without being removed after processing.

[0110] <Other Examples> The present invention has been described in detail above based on its preferred embodiments, but the present invention is not limited to the above embodiments, and various modifications are possible based on the gist of the present invention, and these modifications are not excluded from the scope of the present invention. [Explanation of symbols]

[0111] 1 Base material 2 Parts to be fastened 3 Fasteners 31 volts 32 Auxiliary parts 321 stepped washer 322 Washer

Claims

1. A fastening structure for fastening a first member, which is placed on a predetermined surface of a fastened member, to the fastened member using a fastener, the fastener includes a fastening member configured to be able to be threadedly engaged with the fastened member, and a second member that is fastened to the fastened member together with the first member when the fastening member is threadedly engaged with the fastened member, the second member includes a portion made of a first material and a portion made of a second material different from the first material; the fastening member is made of the second material, a difference between a length effective for fastening of a portion of the second member made of the second material in a direction in which the fastening member is screwed into the fastened member and a length effective for fastening of a portion of the fastening member made of the second material when the fastener is fastened to the fastened member is equal to or less than a predetermined threshold value, a difference between an effective length for fastening the first member in a direction in which the fastening member is screwed into the fastened member and an effective length for fastening a portion of the second member made of the first material when the fastener is fastened to the fastened member is equal to or less than the predetermined threshold value; The threshold is an error tolerance. A fastening structure characterized by:

2. The fastening member has a male thread portion, The fastening structure according to claim 1, wherein the first member and the second member are fastened to the fastened members by threading the male thread portion of the fastening member into a female thread portion formed in the fastened members.

3. The fastening structure according to claim 1 or 2, wherein the fastening member fastens the fastened members, the first member, and the second member together by threading the fastening member onto a nut.

4. The fastening structure according to any one of claims 1 to 3, wherein the fastening member integrally includes a portion made of the first material and a portion made of the second material.

5. The fastening structure according to claim 1 , wherein the fastened member and the first member are made of different materials.

6. 2. The fastening structure according to claim 1, wherein the first member is also disposed on a surface of the fastened member opposite to the predetermined surface.

7. An optical system; a fastening structure according to any one of claims 1 to 6 for fastening the optical system to another member; An optical device comprising:

8. 1. A molding apparatus for molding a composition on a substrate, comprising: an optical system that exposes the composition on the substrate; A molding device comprising the fastening structure according to any one of claims 1 to 6 for fastening the optical system to another member.

9. a molding step of molding the composition on the substrate using the molding apparatus according to claim 8; a processing step of processing the substrate that has undergone the molding step; manufacturing an article from the substrate processed in the processing step; A method for manufacturing an article, comprising:

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