Fixing device, measuring head and displacement sensor device

Abstract

The invention provides a fixing device, a measuring head and a displacement sensor device. A plurality of optical axes of a plurality of measuring heads may be arranged at a higher density while achieving position adjustments for the optical axis of each of the plurality of measuring heads. The fixture includes a first adjustment screw that moves the head holder supported by the base housing in a first adjustment direction, and a second adjustment screw that moves the head holder in a second adjustment direction different from the first adjustment direction. The plurality of fixtures are configured to align in a common attitude in a predetermined alignment direction (e.g., Y-direction), and the first and second adjustment directions intersect the alignment direction.

Description

Technical Field

[0001] The present invention relates to a fixture configured to attach a measuring head for measuring a physical quantity to a mounting surface, a measuring head attached to the mounting surface using the fixture, and a displacement sensor device including the measuring head. Background Art

[0002] An example of a device for measuring the displacement of the surface of a measurement object by a non-contact method includes a confocal displacement sensor, which includes a white light source, an optical fiber, and a measuring head. In the confocal displacement sensor, light (white light) of a wide wavelength band generated by a white light source is guided to the measuring head through the optical fiber. The measuring head includes an optical system (e.g., a plurality of lenses) and a main housing that accommodates the optical system, and the light guided through the optical fiber is emitted to the measurement object through the optical system. At the same time, chromatic aberration is generated in the light emitted to the measurement object through the plurality of lenses. In addition, the measuring head receives light focused and reflected on the surface of the measurement object. The displacement of the surface of the measurement object is measured based on the light received by the measuring head.

[0003] A method is known in which two measuring heads are arranged so as to face each other with a measuring object interposed therebetween and the thickness of the measuring object is measured. In this method, in order to measure the thickness of the measuring object with high accuracy, it is necessary to accurately match the optical axis of the optical system of one measuring head with the optical axis of the optical system of the other measuring head.

[0004] JP 2019-203866A describes a holding device that holds each measuring head so that the position and posture of the measuring head can be adjusted to accurately measure the thickness of the measuring object. The holding device has a configuration in which a plurality of members that can movably and rotatably support the measuring head in multiple directions are provided on a base. In addition, the holding device is provided with a plurality of knobs for moving or rotating the measuring head in multiple directions.

[0005] Therefore, the user can adjust the position and attitude of each measurement head by attaching the base on a desired mounting surface and operating the plurality of knobs.

[0006] Meanwhile, in the case of measuring the thickness of a plurality of portions of the measurement object, it is preferable to prepare a plurality of measuring head groups corresponding to the plurality of portions of the measurement object, respectively, by using two measuring heads as one set of measuring head groups. In this case, the thickness of the plurality of portions of the measurement object is measured simultaneously using the plurality of measuring head groups. Therefore, the efficiency of the thickness measurement is improved compared to the case of measuring the thickness by sequentially moving one set of measuring head groups to the plurality of portions of the measurement object.

[0007] As described above, it is necessary to appropriately arrange the plurality of measuring head groups at positions corresponding to the plurality of parts of the measuring object so that the thickness of the plurality of parts of the measuring object can be measured simultaneously using the plurality of measuring head groups. In addition, it is preferred to arrange the optical axes of the plurality of measuring heads at a high density so as to measure the thickness of more parts of the measuring object.

[0008] However, each of the multiple measuring heads is held by a holding device. Therefore, the density at which the optical axes of the multiple measuring heads can be arranged is limited to the extent that the multiple holding devices do not interfere with each other. In addition, the holding device for the measuring head described in JP 2019-203866A includes multiple knobs operated by the user. Therefore, a working space is required around the knob for the user to operate each knob. When ensuring such a working space, it is more difficult to densely arrange the optical axes of the multiple measuring heads. Summary of the invention

[0009] An object of the present invention is to provide a fixture that enables multiple optical axes of multiple measuring heads to be arranged at a higher density while achieving position adjustment of the optical axes of the multiple measuring heads respectively, a measuring head attached to a mounting surface using the fixture, and a displacement sensor device including the measuring head.

[0010] According to one embodiment of the present invention, a fixture is a fixture configured to attach a measuring head to a mounting surface, the measuring head having an optical axis extending in one direction and acquiring physical quantities related to a measuring object arranged on the optical axis, and the fixture includes: a head holder that holds the measuring head; a base shell that is configured to be attachable to the mounting surface and to movably support the head holder on a surface that is orthogonal to the optical axis of the measuring head held by the head holder; a first adjustment screw that moves the head holder supported by the base shell on the surface in a first adjustment direction; and a second adjustment screw that moves the head holder supported by the base shell in a first adjustment direction. The head holder supported by the base shell is moved on the one surface in a second adjustment direction different from the first adjustment direction; and a switching part, which switches the state of the head holder supported by the base shell between a fixed state in which the head holder cannot move on the one surface and a released state in which the head holder can move on the one surface, and the base shell is configured in such a manner that a plurality of base shells including the base shell are arranged to be aligned in a predetermined alignment direction in a common posture on the mounting surface, and when the plurality of base shells are aligned in the alignment direction in the common posture on the mounting surface, each of the first adjustment direction and the second adjustment direction intersects with the alignment direction.

[0011] According to another embodiment of the present invention, the measuring head is a measuring head attached to the above-mentioned fixture as the first measuring head or the second measuring head, and includes an optical system holder that holds an optical system corresponding to the optical axis, wherein the optical system and the optical system holder are configured to offset an error in the result of measurement of the thickness of the measuring object caused by a change in the holding position of the measuring head held by the frame body and the fixture during measurement of the thickness of the measuring object using a frame body, when the holding position of the measuring head held by the frame body and the fixture on the optical axis changes with changes in the temperature environment.

[0012] According to another embodiment of the present invention, a displacement sensor device includes the above-mentioned first measuring head; the above-mentioned second measuring head; a matching degree determination unit, which determines the matching degree based on the intensity of light emitted from one of the first measuring head and the second measuring head and incident on the other measuring head when the first measuring head and the second measuring head are arranged to face each other, the matching degree indicating how much the optical axis of the first measuring head matches the optical axis of the second measuring head; and an information communication unit, which sends the matching degree determination result obtained by the matching degree determination unit to a predetermined external device.

[0013] According to the present invention, the position of the optical axis of each of the plurality of measuring heads can be adjusted, and the plurality of optical axes of the plurality of measuring heads can be arranged at a higher density. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic diagram illustrating the configuration of a confocal displacement sensor according to an embodiment of the present invention;

[0015] Figure 2 is a view illustrating an example of a specific configuration for measuring the thickness of a conveyed measurement object using a plurality of sets of measurement heads;

[0016] Figure 3 It is observed along the X direction including Figure 2 A side view of the configuration of the frame body in FIG.

[0017] Figure 4 is used to describe the adjustment attached to Figure 2 A working view of the position of the optical axis of each of the plurality of measuring heads in the frame body;

[0018] Figure 5 is provided in Figure 2 An exploded perspective view of a fixing device in a first beam portion of FIG.

[0019] Figure 6 yes Figure 5 A plan view, a side view of one side, and an end view of one side of the first body;

[0020] Figure 7 yes Figure 5 A bottom view of the first subject in FIG.

[0021] Figure 8 yes Figure 5 A plan view, a side view of one side, and an end view of one side of the second body;

[0022] Fig. 9 yes Figure 5 A bottom view of the second subject in FIG.

[0023] Fig.10 yes Figure 5 A plan view, a side view of one side, and an end view of one side of the head holder in FIG.

[0024] Fig.11 yes Figure 5 A bottom view of the head holder in FIG.

[0025] Fig.12 yes Figure 5 A plan view of a rotation force blocking member in FIG.

[0026] Fig.13 Is used to describe the use Figure 5 The fixture in the Figure 3 a view of the procedure on a lower surface of the first beam portion;

[0027] Fig.14 The picture is close to Figure 3 The first beam portion of the embodiment provides an external perspective view of two fixing devices;

[0028] Fig.15 It is cut along the horizontal virtual plane Fig.14 A horizontal cross-sectional view of two fixtures in FIG.

[0029] Fig.16 is provided in Figure 2 An exploded perspective view of a fixing device in the second beam portion;

[0030] Fig.17 Is used to describe the use Fig.16 The fixture in the Figure 3 a view of the procedure on an upper surface of the second beam portion;

[0031] Fig.18 is a block diagram illustrating a functional configuration implemented in a PC by executing a matching degree communication program; and

[0032] Fig.19 This is a flowchart of the matching degree communication process based on the matching degree communication program. DETAILED DESCRIPTION

[0033] The measuring head according to the present invention is a measuring head having an optical axis extending in one direction and acquiring a physical quantity related to a measuring object arranged on the optical axis. In addition, the fixture according to the present invention is a fixture for attaching the measuring head to, for example, a predetermined mounting surface. Hereinafter, the fixture and the measuring head according to one embodiment of the present invention will be described with reference to the accompanying drawings.

[0034] Hereinafter, as an example of a measuring head, a measuring head for a confocal displacement sensor that acquires a distance from the measuring head to a measurement object arranged on an optical axis thereof as a physical quantity will be described.

[0035] 1. Configuration of the confocal displacement sensor including the measuring head

[0036] First, the configuration of a confocal displacement sensor including a measuring head is described. Figure 1 Schematic diagram illustrating the configuration of a confocal displacement sensor according to an embodiment of the present invention; Figure 1 As shown, the confocal displacement sensor 9 includes measuring heads 1A and 1B, measuring units 100A and 100B, light guide units 300A and 300B, a control unit 2, and a personal computer (PC) 3. The light guide unit 300A includes a plurality of optical fibers and optically connects some constituent elements (a light projection unit 120 and a spectroscope unit 130 to be described later) inside the measuring head 1A and the measuring unit 100A.

[0037] The measuring unit 100A includes a unit housing 110, a light projection unit 120, a spectroscope unit 130, a light receiving unit 140, a measurement control unit 150, and a sub-display unit 190. The unit housing 110 accommodates the light projection unit 120, the spectroscope unit 130, the light receiving unit 140, and the measurement control unit 150. The sub-display unit 190 includes a display such as a seven-segment display or a dot matrix display. The light projection unit 120 includes a white light source that generates light having a wide and continuous wavelength band (e.g., 500nm to 700nm), that is, light having a plurality of continuous wavelengths (white light), and is configured to be able to emit light generated from the white light source. The light emitted by the light projection unit 120 is input to the optical fiber 311 of the light guide unit 300A, which will be described later.

[0038] The spectroscope unit 130 includes a diffraction grating 131 and a plurality of (in this example, two) lenses 132 and 133. As will be described later, a portion of the light emitted by the light projection unit 120 and reflected by the surface of the measuring object S is output from the optical fiber 312 of the light guide unit 300A, which will be described later. The light output from the optical fiber 312 passes through the lens 132 to be substantially collimated and is incident on the diffraction grating 131. The diffraction grating 131 is a reflective diffraction grating. The light incident on the diffraction grating 131 is partitioned so as to be reflected at different angles for each wavelength, and passes through the lens 133 to be focused on different positions in one dimension for each wavelength.

[0039] The light receiving unit 140 includes an imaging element (one-dimensional line sensor) in which a plurality of pixels are arranged one-dimensionally. The imaging element may be a multi-partitioned photodiode (PD), a charge coupled device (CCD) camera, or a complementary metal oxide semiconductor (CMOS) image sensor, or may be another element. The light receiving unit 140 is arranged so that a plurality of pixels of the imaging element receive light at a plurality of focus positions, which are different for each wavelength and are formed by the lens 133 of the spectroscope unit 130. An analog electrical signal (hereinafter referred to as a light receiving signal) corresponding to the amount of received light is output from each pixel of the light receiving unit 140. The light receiving signal indicates the intensity of the light received by each pixel.

[0040] The measurement control unit 150 includes a central processing unit (CPU) and a memory or a microcomputer. The measurement control unit 150 stores a control program and stores various types of data such as measurement conditions for displacement measurement. These data are given from the control unit 2 to be described later. The measurement control unit 150 controls the light projection unit 120 and the light receiving unit 140 based on the stored control program and data, and calculates the displacement of the surface of the measurement object S based on the light reception signal output from the light receiving unit 140. The measurement control unit 150 causes the sub-display unit 190 to display the calculation result of the displacement.

[0041] The measurement control unit 150 is connected to the control unit 2, and the control unit 2 is also connected to the PC 3. The measurement control unit 150 provides the control unit 2 with the calculation result of the displacement and the light reception signal output from the light reception unit 140. The configuration and operation of the control unit 2 and the PC 3 will be described later.

[0042] The measuring head 1A includes a head housing 10, a fiber receptacle 30, and a plurality of (in this example, four) lenses 221, 222, 223, and 224, and has a cylindrical outer circumferential surface. The head housing 10 accommodates the plurality of lenses 221, 222, 223, and 224, and forms the outer shape of the measuring head 1A.

[0043] The fiber receptacle 30 is attached to the head housing 10. A fiber connector 330 (to be described later) of the light guide unit 300A is connected to the fiber receptacle 30. The fiber connector 330 holds one end portion of an optical fiber 319 of the light guide unit 300A, which will be described later.

[0044] Light is guided from the measuring unit 100A to the optical fiber 319 by the light guiding unit 300A. The light guided to the optical fiber 319 is output from the optical fiber 319 in the head housing 10 of the measuring head 1A, and passes through a plurality of lenses 221, 222, 223, and 224 in sequence. In the present embodiment, each of the plurality of lenses 221, 222, 223, and 224 is configured using a single member made of glass. In addition, the lens 221 is a magnifying lens that magnifies the light guided from the optical fiber 319. The lenses 222 and 223 are curved lenses that converge the light magnified by the lens 221 while adding a predetermined function. In addition, the lens 224 is a chromatic aberration lens that generates chromatic aberration in the light guided from the lens 223. The light that generates chromatic aberration when passing through the plurality of lenses 221, 222, 223, and 224 is focused at a position near the surface of the measuring object S.

[0045] The light guide unit 300A includes optical fibers 311, 312, and 319, an optical fiber coupler 320, and an optical fiber connector 330. Figure 1 In the example of FIG. 1 , the fiber coupler 320 is provided in the unit housing 110 of the measuring unit 100A. The fiber connector 330 is connected to the measuring head 1A as described above.

[0046] The optical fiber coupler 320 has a so-called 2×2 type configuration, and includes four ports 321 to 323 and a body 324. Figure 1 , illustration of one of the four ports is omitted. Ports 321 and 322 and port 323 are connected to the body 324 so as to face each other, wherein the body 324 is interposed between the ports 321 and 322 and the port 323. Light input to at least one of the ports 321 and 322 is output from the port 323. Light input to the port 323 is output from each of the ports 321 and 322.

[0047] The optical fibers 311 and 312 are connected to ports 321 and 322 of the optical fiber coupler 320, respectively. The other end portion of the optical fiber 319 is connected to a port 323 of the optical fiber coupler 320.

[0048] According to this configuration, light emitted by the light projection unit 120 of the measuring unit 100A is input to the port 321 of the fiber coupler 320 through the optical fiber 311. The light input to the port 321 is output from the port 323 and is guided to the measuring head 1A through the optical fiber 319. The light guided to the measuring head 1A is emitted to the measuring object S through the plurality of lenses 221, 222, 223, and 224.

[0049] A portion of the light reflected by the surface of the measuring object S is input to one end portion of the optical fiber 319 through the plurality of lenses 224, 223, 222, and 221. The light input to one end portion of the optical fiber 319 is input to the port 323 of the fiber coupler 320. The light input to the port 323 is output from the ports 321 and 322. The light output from the port 322 is guided to the spectroscope unit 130 through the optical fiber 312. Thus, the displacement of the measuring object S is calculated based on the light emitted from the measuring unit 100A to the measuring object S.

[0050] The measuring unit 100A and the measuring unit 100B have the same configuration, the measuring head 1A and the measuring head 1B have the same configuration, and the light guide unit 300A and the light guide unit 300B have the same configuration. Some constituent elements inside the measuring head 1B and the measuring unit 100B are optically connected through the light guide unit 300B, similar to the example of connection between the measuring head 1A and the measuring unit 100A described above. In addition, the measurement control unit 150 (not shown) of the measuring unit 100B is connected to the control unit 2.

[0051] The measuring object S is irradiated with light emitted from the light projection unit 120 (not shown) of the measuring unit 100B through the measuring head 1B. A part of the light reflected by the surface of the measuring object S returns to the measuring unit 100B through the measuring head 1B. Therefore, the displacement of the measuring object S is calculated based on the light emitted from the measuring head 1B to the measuring object S. In this case, the measurement control unit 150 (not shown) provided in the measuring unit 100B gives the calculation result of the displacement and the light reception signal output from the light receiving unit 140 to the control unit 2.

[0052] The control unit 2 includes a CPU and a memory or a microcomputer. For example, the displacement measurement conditions in the measuring units 100A and 100B are input to the control unit 2 from the PC 3. The measurement conditions include, for example, the light emission amount in the light projection unit 120, the light emission timing in the light projection unit 120, the exposure amount in the light receiving unit 140, etc. The control unit 2 gives the input measurement conditions to the measurement control unit 150 of each of the measuring units 100A and 100B. The measurement operation based on the given measurement conditions is performed in each of the measuring units 100A and 100B.

[0053] The PC 3 includes a CPU 3a and a memory 3b. The memory 3b stores various programs related to the thickness measurement of the measuring object S to be described later and various types of data for the thickness measurement, and the CPU 3a executes the programs stored in the memory 3b. The calculation result of the displacement and the light reception signal given from each of the measuring units 100A and 100B to the control unit 2 are given from the control unit 2 to the PC 3.

[0054] A main display unit 4a and an operation unit 4b are connected to the PC 3. The main display unit 4a includes, for example, a display device such as an organic electroluminescent (EL) panel or a liquid crystal display panel. The operation unit 4b includes a keyboard and a pointing device. The pointing device includes a mouse, a joystick, etc. The user can give various instructions related to thickness measurement to the PC 3 by operating the operation unit 4b.

[0055] In the confocal displacement sensor 9, the measuring heads 1A and 1B are arranged so as to face each other with the measuring object S interposed between the measuring heads 1A and 1B. Figure 1 As shown. The measuring object S has a first surface and a second surface opposite to each other. In this state, if the distance between the measuring heads 1A and 1B (head-to-head distance) is known, the thickness measurement of the measuring object S can be performed based on the displacement of the first surface and the second surface of the measuring object S measured by the measuring units 100A and 100B and the head-to-head distance.

[0056] 2. Use Figure 1 Example of Thickness Measurement of a Measurement Object S Using the Confocal Displacement Sensor 9

[0057] The thickness measurement of the measuring object S using two measuring heads 1A and 1B can be effectively used for the inspection of the thickness of sheet-like molded articles at a production site such as a factory (online inspection). For example, it is assumed that the sheet-like molded articles are conveyed on a linearly extending conveying path at the production site. Therefore, a set of measuring heads 1A and 1B are arranged at one measuring position on the conveying path so as to face each other with the molded article interposed therebetween. In this case, the thickness of a portion of the molded article passing through one measuring position of the conveying path can be effectively measured.

[0058] When multiple sets of measuring heads 1A and 1B are respectively arranged at multiple measuring positions on the conveying path, the thickness of multiple parts of the molded article passing through the multiple measuring positions on the conveying path can be measured. In this case, by aligning the multiple measuring positions in a direction intersecting the conveying direction of the molded article, the thickness of many parts of the molded article can be measured.

[0059] Figure 21A and 1B are views illustrating an example of a specific configuration for measuring the thickness of a conveyed measuring object S using a plurality of sets of measuring heads 1A and 1B. Figure 2 As indicated by the dot pattern in FIG. 1 , in this example, the measuring object S whose thickness is to be measured is a sheet-like molded article (strip-like molded article) extending in one direction with a constant width. The molded article is measured along the direction in which the molded article extends in the horizontal plane (see FIG. 1 ). Figure 2 The thick solid arrow in the figure transmits.

[0060] The frame body 900 is used in order to measure the thickness of a plurality of portions of a measuring object S to be conveyed, in other words, in order to arrange a plurality of sets of measuring heads 1A and 1B at a plurality of measuring positions on a conveying path of the measuring object S, respectively. Arrows indicating the X direction, the Y direction, and the Z direction orthogonal to each other are attached to Figure 2 and predetermined views to be described later in order to clarify the positional relationship between the measuring object S, the frame main body 900 and other constituent elements. The X direction is a direction parallel to the conveying direction of the measuring object S, and the Y direction is a direction orthogonal to the X direction in the horizontal plane. In addition, the Z direction corresponds to the vertical direction.

[0061] The frame body 900 is a single member including a metal material such as stainless steel, and includes a first beam portion 910, a second beam portion 920, a third beam portion 920, and two column portions 930. The first beam portion 910 and the second beam portion 920 both extend in the Y direction and are arranged to be aligned at a certain interval in the Z direction. The first beam portion 910 is located above the second beam portion 920. One of the two column portions 930 extends in the Z direction and couples one end portion of the first beam portion 910 and one end portion of the second beam portion 920. The other of the two column portions 930 extends in the Z direction and couples the other end portion of the first beam portion 910 and the other end portion of the second beam portion 920. In addition, the frame body 900 is supported by two frame body support members 950 so that the measurement object S passes through a space surrounded by the first beam portion 910, the second beam portion 920, and the two column portions 930.

[0062] For attachment Figure 1 A plurality of (in this example, seven) attachment portions 919 of the measuring head 1A in the embodiment are provided on the first beam portion 910 of the frame body 900 so as to be aligned to be substantially continuous in the Y direction. The measuring head 1A can be attached to each attachment portion 919 via the fixture 400. The details of the fixture 400 will be described later.

[0063] In addition, for attachment Figure 1A plurality of (in this example, seven) attachment portions 929 of the measuring head 1B in the embodiment are provided on the second beam portion 920 of the frame body 900 so as to be aligned to be substantially continuous in the Y direction. The measuring head 1B can be attached to each attachment portion 929 via the fixture 500. The details of the fixture 500 will be described later.

[0064] The plurality of attachment portions 919 of the first beam portion 910 respectively face the plurality of attachment portions 929 of the second beam portion 920 in the Z direction. The thickness of a portion of the measurement object S located between each set of the measurement heads 1A and 1B can be measured by attaching a set of the measurement heads 1A and 1B to each set of the attachment portions facing each other in the Z direction among the plurality of attachment portions 919 and 929. Figure 2 In the example of FIG. 1 , two sets of measuring heads 1A and 1B are respectively attached to two sets of attachment parts facing each other in the Z direction among the plurality of attachment parts 919 and 929 of the frame body 900. This makes it possible to simultaneously measure the thickness of two portions of the measurement object S located between the two sets of measuring heads 1A and 1B.

[0065] Figure 3 It is observed along the X direction including Figure 2 A side view of the configuration of the frame body 900. Figure 3 , an enlarged view illustrating the attachment state of the plurality of measuring heads 1A in the first beam portion 910 is illustrated in a dotted line balloon-shaped dialog box. In addition, an enlarged view illustrating the attachment state of the plurality of measuring heads 1B in the second beam portion 920 is illustrated in a single-point chain line balloon-shaped dialog box.

[0066] like Figure 3 As shown in the dotted balloon-shaped dialog box in FIG. 1 , the first beam portion 910 has an upper surface 911 and a lower surface 912. In the first beam portion 910, the lower surface 912 is a mounting surface for attaching a plurality of measuring heads 1A. As will be described later, the measuring head 1A is composed of some constituent elements (described later) included in the fixture 400. Figure 5The fixture 400 is arranged on the lower surface 912 of the first beam portion 910 and is screwed to the first beam portion 910 using a plurality of (e.g., three) screws. Therefore, a plurality of attachment portions 919 of the first beam portion 910 are formed with a plurality of through holes 913 for screwing the fixture 400 from the upper surface 911 through the inner side of the first beam portion 910. Each through hole 913 is formed so that the inner diameter near the lower end portion is smaller than the inner diameter of the head of the screw so that the screw inserted from above does not pass downward. In addition, each attachment portion 919 of the first beam portion 910 is formed with a through hole 914 that allows the user to approach the fixture 400 from above in a state where the fixture 400 is attached to the attachment portion 919, as indicated by the double-dotted line in the dotted balloon-shaped dialog box. The through hole 914 also serves as a path for pulling out the optical fiber 319 extending from the measuring head 1A to the outside of the frame main body 900 in a state where the measuring head 1A is attached to the attachment portion 919 .

[0067] like Figure 3 As shown in the single-dot chain line balloon dialog box in FIG. 1 , the second beam portion 920 has an upper surface 921 and a lower surface 922. In the second beam portion 920, the upper surface 921 is a mounting surface for attaching a plurality of measuring heads 1B. As will be described later, the measuring heads 1B are composed of some constituent elements (described later) included in the fixture 500. Fig.16 The base portion 510 and the retaining member 550 in the second beam portion 920 are held. In this state, the fixture 500 is arranged on the upper surface 921 of the second beam portion 920 and is screwed to the second beam portion 920 using multiple (e.g., three) screws. Therefore, the multiple attachment portions 929 of the second beam portion 920 are formed with multiple through holes 923 for screwing the fixture 500 from the lower surface 922 through the inner side of the second beam portion 920. Each through hole 923 is formed so that the inner diameter near the upper end portion is smaller than the inner diameter of the head of the screw, so that the screw inserted from below does not pass upward. In addition, each attachment portion 929 of the second beam portion 920 is formed with a through hole 924, which allows the user to approach the fixture 500 from below in a state where the fixture 500 is attached to the attachment portion 929, as indicated by the double dotted line in the balloon-shaped dialog box of the single dotted line. The through hole 924 also serves as a path for pulling out the optical fiber 319 extending from the measuring head 1B to the outside of the frame main body 900 in a state where the measuring head 1B is attached to the attachment portion 929 .

[0068] Here, when the plurality of lenses 221, 222, 223, and 224 ( Figure 1 ) is regarded as one optical system, the optical axis of the one optical system is referred to as the optical axis of each of the measuring heads 1A and 1B.

[0069] The fixture 400 and the frame body 900 are configured so that the optical axis of the measuring head 1A extends parallel to the Z direction when the measuring head 1A is attached to the frame body 900. In addition, the fixture 500 and the frame body 900 are configured so that the optical axis of the measuring head 1B extends parallel to the Z direction when the measuring head 1B is attached to the frame body 900.

[0070] As described in the background art, in order to measure the thickness of the measuring object S with high accuracy using two measuring heads 1A and 1B, it is necessary to accurately match the optical axis of one measuring head 1A with the optical axis of the other measuring head 1B. Therefore, the fixture 400 according to the present embodiment is configured so that the position of the optical axis of the measuring head 1A can be adjusted in a plane orthogonal to the optical axis in a state where the measuring head 1A is attached to the frame body 900.

[0071] Figure 4 is used to describe the adjustment attached to Figure 2 A working view of the position of the optical axis of each of the multiple measuring heads 1A in the frame main body 900. Figure 4 A plan view of two fixtures 400 and two measuring heads 1A viewed through the frame body 900 is illustrated.

[0072] In this example, the plurality of measuring heads 1A are attached to the plurality of attachment portions 919 of the first beam portion 910 via the plurality of fixtures 400. Therefore, the plurality of fixtures 400 are aligned in the Y direction on the lower surface 912 of the first beam portion 910. In this state, as shown by Figure 4 As indicated by arrows AA1 and AA2 in FIG. 1 , each fixture 400 is configured so that a user can operate the device described later by tilting from two directions in the X direction and the Y direction relative to the horizontal plane. Figure 5 The position of the optical axis LA of the measuring head 1A is adjusted by using the two adjustment screws S2.

[0073] In this case, for example, when the user follows the Figure 4 When the user performs adjustment work in the direction indicated by the white arrow AA1 shown in the balloon-shaped dialog box in FIG. 1 , the position of the optical axis LA is adjusted in the first adjustment direction D1 along the arrow AA1. In addition, for example, when the user performs adjustment work in the direction indicated by the white arrow AA2, the position of the optical axis LA is adjusted in the second adjustment direction D2 along the arrow AA2.

[0074] As described above, each fixture 400 can adjust the position of the optical axis LA of the measuring head 1A from a direction inclined relative to the alignment direction (Y direction) of the plurality of fixtures 400 and a direction (X direction) orthogonal thereto in the horizontal plane. Therefore, there is no need to provide a work space for adjusting the position of the optical axis LA between the plurality of fixtures 400. Figure 4 As indicated by the single-point dashed line in FIG. 4 , the user can stand in the areas AR1 and AR2 adjacent to the conveying path of the measuring object S in the plan view and adjacent to the frame body 900. In this case, the direction in which the user is facing is easily matched with the direction of the position adjustment work of the optical axis LA by causing the user to face each fixture 400. Therefore, the position adjustment work of the optical axis LA becomes easy.

[0075] 3. Details of the Fixing Device 400

[0076] (a) Overview of the configuration of the fixing device 400

[0077] Figure 5 is provided in Figure 2 910 in FIG. 1 is an exploded perspective view of the fixture 400 on the first beam portion 910 in FIG. Arrows indicating the x-direction, the y-direction, and the z-direction orthogonal to each other are attached to Figure 5 and predetermined views described later in order to clarify the positional relationship between the plurality of component elements of the fixture 400. In addition, in the x direction, the direction in which the arrow x is oriented in the drawings is appropriately referred to as the +x direction, and the opposite direction thereof is appropriately referred to as the -x direction in the following description. In addition, in the y direction, the direction in which the arrow y is oriented in the drawings is appropriately referred to as the +y direction, and the opposite direction thereof is appropriately referred to as the -y direction. In addition, in the z direction, the direction in which the arrow z is oriented in the drawings is appropriately referred to as the +z direction, and the opposite direction thereof is appropriately referred to as the -z direction.

[0078] like Figure 5 As shown, the fixing device 400 mainly includes a base housing 410, a head holder 460 and a rotational force blocking member 480, and is manufactured by connecting a plurality of these members. The base housing 410 also includes a first body 420 and a second body 440. First, the structure of each of the first body 420, the second body 440, the head holder 460 and the rotational force blocking member 480 will be described.

[0079] (b) First body 420

[0080] Figure 6 yes Figure 5 A plan view, a side view of one side, and an end view of one side of the first body 420 in FIG. Figure 7 yes Figure 5 A bottom view of the first body 420 in FIG. Figure 6 and 7 In the plan view, the plane view is viewed in the -z direction. Figure 5 The side view of the first body 420 is viewed in the -y direction. Figure 5 In addition, the end view of one side is observed in the -x direction. Figure 5 The bottom view is viewed in the +z direction. Figure 5 4. A view of the first body 420 in FIG.

[0081] The first body 420 is a single member including a metal material such as stainless steel, and includes a plate-shaped portion 421, a first end surface forming portion 431, and a second end surface forming portion 432. Figure 6 As shown. The plate-like portion 421 has a generally rectangular shape that is slightly long in the x direction in a plan view, and has a constant thickness in the z direction. The first end surface forming portion 431 and the second end surface forming portion 432 are formed so as to extend a certain distance in the +z direction from both end portions of the plate-like portion 421 in the x direction.

[0082] The plate-like portion 421 has a first surface 422 facing the +z direction and a second surface 423 facing the -z direction. The first surface 422 of the plate-like portion 421 is located between the first end surface forming portion 431 and the second end surface forming portion 432 in the x direction. The first surface 422 is processed to be flat so that unevenness is reduced as much as possible. A circular head opening 424 into which the measuring head 1A can be inserted is formed in the central portion of the plate-like portion 421. In addition, two threaded holes 425 are formed in the plate-like portion 421 to sandwich the head opening 424 in the longitudinal direction of the plate-like portion 421. The two threaded holes 425 open in the +z direction.

[0083] The first end surface forming portion 431 is formed in a plate shape having a constant thickness in the x direction. Two through holes 431h are formed in a substantially central portion of the first end surface forming portion 431 in the z direction. In a plan view, the through holes 431h extend in directions inclined relative to the x direction and the y direction, respectively. In addition, a protrusion 431p is formed in a central portion in the y direction of a distal portion in the z direction of the first end surface forming portion 431. In a plan view, a threaded hole sha is formed in a central portion of the protrusion 431p. Two threaded holes shb are formed in a portion (two end portions) of the distal portion of the first end surface forming portion 431 other than the protrusion 431p.

[0084] The second end surface forming portion 432 is formed in a plate shape having a constant thickness in the x direction, similar to the first end surface forming portion 431. In addition, two through holes 432h are also formed in the approximate center portion of the second end surface forming portion 432 in the z direction, similar to the first end surface forming portion 431. In a plan view, the through holes 432h extend in directions inclined relative to the x direction and the y direction, respectively. In addition, two protrusions 432p are formed at two end portions in the y direction of the distal portion of the second end surface forming portion 432 in the z direction. In a plan view, a threaded hole sha is formed in the center portion of each protrusion 432p. A threaded hole shb is formed in a portion (center portion) of the distal portion of the second end surface forming portion 432 except the two protrusions 432p.

[0085] (c) Second body 440

[0086] Figure 8 yes Figure 5 A plan view, a side view of one side, and an end view of one side of the second body 440 in FIG. Fig. 9 yes Figure 5 A bottom view of the second body 440 in FIG. Figure 8 and Fig. 9 In the plan view, the plane view is viewed in the -z direction. Figure 5 The side view of the second body 440 is viewed in the -y direction. Figure 5 In addition, the end view of one side is observed in the -x direction. Figure 5 The bottom view is viewed in the +z direction. Figure 5 4. A view of the second body 440 in FIG.

[0087] The second body 440 is a single member including a metal material such as stainless steel, and includes a plate-shaped portion 441, a first side surface forming portion 451, and a second side surface forming portion 452. Figure 8 As shown. The plate-like portion 441 has a generally rectangular shape that is slightly long in the x direction in a plan view, and has a constant thickness in the z direction. The first side surface forming portion 451 and the second side surface forming portion 452 are formed so as to extend a certain distance in the -z direction from two side portions of the plate-like portion 441 in the generally y direction.

[0088] The plate-like portion 441 has a first surface 442 facing the +z direction and a second surface 443 facing the -z direction. A holder opening 444 having a substantially regular hexagonal shape is formed in the center portion of the plate-like portion 441, and a tubular portion 461 ( Fig.10) can be inserted into the holder opening 444. In addition, in the plate-like portion 441, two through holes 445 are formed so as to sandwich the holder opening 444 in the longitudinal direction of the plate-like portion 441.

[0089] In addition, the protruding portion 431p ( Figure 6 A notch 446a into which the plate-like portion 441 can be fitted is formed in the center portion in the y direction of the end portion in the +x direction of the plate-like portion 441. Two through holes nh are formed in portions (two end portions) other than the notch 446a of the end portion in the +x direction of the plate-like portion 441.

[0090] In addition, the two protruding portions 432p ( Figure 6 Two recesses 446b into which the plate-like portion 441 can be fitted are formed at both end portions in the y direction of the end portion in the x direction of the plate-like portion 441. One through hole nh is formed in a portion (central portion) other than the two recesses 446b of the end portion in the x direction of the plate-like portion 441.

[0091] The first side surface forming portion 451 and the second side surface forming portion 452 are formed so as to accommodate a part of a head holder 460 to be described later in a space in the -z direction from the plate-like portion 441. Therefore, a region between the first side surface forming portion 451 and the second side surface forming portion 452 in a plan view is larger than the outer shape of the head holder 460 in a plan view to a certain extent.

[0092] The first side surface forming portion 451 substantially forms a side surface portion in the +y direction facing the second body 440. The center portion of the first side surface forming portion 451 in the x direction includes a first wall portion w1 and a third wall portion w3, which are bent so as to protrude in the +y direction along a portion of the inner edge of the holder opening 444 in a plan view and are inclined relative to the x direction and the y direction. A screw hole shc is substantially formed in a center portion of each of the first wall portion w1 and the third wall portion w3.

[0093] The second side surface forming portion 452 basically forms a side surface portion facing the -y direction of the second body 440, and extends in the x direction. The center portion of the second side surface forming portion 452 in the x direction is bent so that the other portion along the inner edge of the holder opening 444 in a plan view protrudes in the -y direction, and includes a second wall portion w2 and a fourth wall portion w4 inclined with respect to the x direction and the y direction. A spring accommodating portion sf capable of accommodating a spring is formed in a substantially central portion of each of the second wall portion w2 and the fourth wall portion w4.

[0094] In a plan view, the first wall portion w1 of the first side surface forming portion 451 and the second wall portion w2 of the second side surface forming portion 452 face each other with the retainer opening 444 interposed therebetween. In addition, the third wall portion w3 of the first side surface forming portion 451 and the fourth wall portion w4 of the second side surface forming portion 452 face each other with the retainer opening 444 interposed therebetween.

[0095] If through Fig. 9 As indicated by the dotted lines in FIG. 4 , in the process of assembling the fixture 400, the adjustment screw s2 is screwed into two threaded holes shc formed in the first wall portion w1 and the third wall portion w3 of the first side surface forming portion 451, respectively. In the process of assembling the fixture 400, the spring sp is accommodated in two spring accommodation portions sf formed in the third wall portion w3 and the fourth wall portion w4 of the second side surface forming portion 452, respectively.

[0096] (d) Head holder 460

[0097] Fig.10 yes Figure 5 A plan view, a side view of one side, and an end view of one side of the head holder 460 in FIG. Fig.11 yes Figure 5 A bottom view of the head holder 460 in FIG. Fig.10 and Fig.11 In the plan view, the plane view is viewed in the -z direction. Figure 5 The side view of the head holder 460 is viewed in the -y direction. Figure 5 In addition, the end view of one side is viewed in the -x direction. Figure 5 The bottom view is viewed in the +z direction. Figure 5 View of the head holder 460 in FIG.

[0098] The head holder 460 is a single member including a metal material such as stainless steel, and includes a tubular portion 461 and a plurality of supported portions 464a, 464b, 464c, and 464d, as shown in FIG. Fig.10 The tubular portion 461 is formed to extend a predetermined distance in the z direction, and has one end portion 461a facing the +z direction and the other end portion 461b facing the -z direction. In addition, the tubular portion 461 has a cylindrical inner circumferential surface slightly larger than the outer circumferential surface of the measuring head 1A, and has a tubular outer circumferential surface whose cross section orthogonal to the axial direction is a regular hexagon or a substantially regular hexagon.

[0099] Here, the tubular portion 461 has a first tubular portion 462 and a second tubular portion 463 which are aligned in sequence from one end portion 461a toward the other end portion 461b. A linear notch cc extending a certain distance in the circumferential direction of the tubular portion 461 is formed in a portion between the first tubular portion 462 and the second tubular portion 463 in the tubular portion 461. Fig.10 In the plan view of FIG. 4 , the range in which the notch cc is formed in the circumferential direction of the tubular portion 461 is indicated by the arrow ARC in the single-dot chain line. As indicated by the arrow ARC, the notch cc of this example is formed in the range of about ¾ of the entire circumference of the tubular portion 461.

[0100] The first tubular portion 462 is configured to be able to Figure 1 The measuring head 1A is held by tightening the outer circumferential surface of the measuring head 1A in a state where the measuring head 1A is inserted into the tubular portion 461. Specifically, the first tubular portion 462 has a clamping portion 462b. Fig.10 In the plan view and the end view of one side, the clamping portion 462b is indicated by a thick dashed frame. The clamping portion 462b is formed to separate a portion of the first tubular portion 462 at a certain interval in the circumferential direction. In addition, the distance between the two separated portions can be adjusted using a screw s5 (described later). Fig.13 ) to adjust.

[0101] The second tubular portion 463 is formed so that the length (height) in the z direction is equal to or greater than the length (height) of the second body 440 in the z direction. Figure 8 The length (height) in the z direction in FIG. Four supported portions 464a, 464d, 464b, and 464c are provided on the outer circumferential surface of the second tubular portion 463 so as to be aligned sequentially in the clockwise direction in a plan view. The four supported portions 464a, 464d, 464b, and 464c are formed to extend a predetermined distance in the +z direction from the other end portion 461b of the tubular portion 461.

[0102] like Fig.10 As shown in the plan view of , four supported portions 464a, 464d, 464b and 464c are arranged at intervals of 90° relative to the axis of the tubular portion 461. Therefore, the supported portion 464a and the supported portion 464b face each other with the tubular portion 461 interposed therebetween in the x-direction. In addition, the supported portion 464c and the supported portion 464d face each other in the y-direction with the tubular portion 461 interposed therebetween.

[0103] An end surface including a tubular portion 461 and four supported portions 464a, 464d, 464b, and 464c is formed at the other end portion 461b of the tubular portion 461. The end surface contacts the first surface 422 of the first body 420 when assembling the fixture 400. Therefore, the end surface is processed to be flat so that unevenness is reduced as much as possible.

[0104] A through hole 465 is formed in the center portion of each of the two supported portions 464a and 464b aligned in the x direction in a plan view. The two through holes 465 of the head holder 460 correspond to Figure 6 The inner diameter of each through hole 465 is substantially larger than the inner diameter of each threaded hole 425 of the first body 420.

[0105] (e) Rotational force blocking member 480

[0106] Fig.12 yes Figure 5 480 is a plan view of the rotational force blocking member 480. Fig.12 The plan view is viewed in the -z direction. Figure 5 4 is a view of a rotational force blocking member 480 in FIG. The rotational force blocking member 480 is a plate-like single member made of a metal material such as stainless steel, and is manufactured, for example, by cutting a plate-like member (metal plate, etc.) having a constant thickness.

[0107] like Fig.12 As shown, the rotational force blocking member 480 includes two screw receiving portions 481 and a coupling portion 482. The two screw receiving portions 481 are arranged at a certain interval in the x direction. The coupling portion 482 is formed into a polygonal shape extending in the x direction, and is bent so as to protrude in the -y direction in a plan view, and couples the two screw receiving portions 481.

[0108] Here, two screw receiving portions 481 are formed so as to be mountable Fig.10 The coupling portion 4821 is formed so that the two screw receiving portions 481 are placed on the two supported portions 464a and 464b of the head holder 460. Fig.10 The head holder 460 is in a state of being on the two supported portions 464a and 464b so as to be able to bypass a portion of the outer circumferential portion of the tubular portion 461.

[0109] In addition, a through hole 481h is formed in a substantially central portion of each of the two screw receiving portions 481. The two through holes 481h are formed so that the two screw receiving portions 481 are placed Fig.10In a state where the head is on the two supported portions 464a and 464b of the head holder 460, the two through holes 465 of the supported portions 464a and 464b are overlapped respectively.

[0110] In addition, the rotation force blocking member 480 is configured to be able to be assembled in Figure 8 The rotational force blocking member 480 is formed so that each screw receiving portion 481 is close to or in contact with the first side surface forming portion 451 and the second side surface forming portion 452 when the rotational force blocking member 480 is assembled into the second body 440.

[0111] (f) Assembly of the Fixing Device 400

[0112] When assembling the fixture 400, first, the head holder 460 is placed on the first surface 422 of the first body 420, as shown in FIG. Figure 5 In addition, the rotational force blocking member 480 is placed on a portion of the head holder 460 so that the two screw receiving portions 481 ( Fig.12 ) is located at the supported portions 464a and 464b of the head holder 460 ( Fig.10 )superior.

[0113] In this state, if Figure 5 As indicated by the thick dot-dash arrows, the two fixing screws s1 pass through the two through holes 481h ( Fig.12 ) and two through holes 465 ( Fig.10 ) are screwed and temporarily fastened to the two threaded holes 425 ( Figure 6 ). Each fixing screw s1 is a screw in which a washer is pre-incorporated. Therefore, in a state where the fixing screw s1 is screwed into the threaded hole 425, the washer is inevitably arranged between the head of the fixing screw s1 and the rotation force blocking member 480. Note that a screw that does not contain a washer may also be used as the fixing screw s1. In this case, it is preferred that the washer is separately attached to the fixing screw s1.

[0114] Here, as described above, the inner diameter of each through hole 465 of the head holder 460 is larger than the inner diameter of each threaded hole 425 of the first body 420, and therefore, in a state where each fixing screw s1 is temporarily fastened in the corresponding threaded hole 425, the head holder 460 can float within a slight range relative to the first body 420. That is, the head holder 460 is in a released state in which it can float relative to the first body 420.

[0115] Next, if through Figure 5 As indicated by the thick solid arrow in FIG. 1 , a spring sp made of metal is attached to two spring receiving portions sf ( Figure 8 ). In addition, if Figure 5 As indicated by the thick dashed arrows in FIG. 1 , the adjustment screws s2 are attached to the two threaded holes shc ( Figure 8 ). Note that a retaining ring (eg, an E-ring) (not shown) for retaining is attached to the adjusting screw s2.

[0116] Thereafter, the second body 440 is placed on the first body 420 so as to cover the head holder 460 and the rotational force blocking member 480. At this time, the rotational force blocking member 480 is accommodated in the first side surface forming portion 451 and the second side surface forming portion 452 ( Figure 8 ) in a space surrounded by the head holder 460. In addition, a portion of the second tubular portion 463 of the head holder 460 and the supported portions 464a to 464d ( Fig.10 ) is accommodated in the first side surface forming portion 451 and the second side surface forming portion 452 of the second body 440 ( Figure 8 ) is surrounded by a space. In addition, the protruding portions 431p and 432p ( Figure 6 ) is assembled into the recesses 446a and 446b of the second body 440 ( Figure 8 )middle.

[0117] In this state, the first tubular portion 462 of the head holder 460 is located on the first surface 442 of the second body 440. In addition, the heads of the two fixing screws s1 are inserted through the two through holes 445 ( Figure 8 ) are exposed on the second body 440. In addition, the three through holes nh ( Figure 8 ) and the three threaded holes shb ( Figure 6 ) overlap. In addition, the protruding portions 431p and 432p ( Figure 6 ) is slightly located in the +z direction from the first surface 442 of the second body 440 and is located in a common plane parallel to the first surface 442 and orthogonal to the z direction. That is, the protrusions 431p and 432p ( Figure 6 ) has a distal end portion that protrudes slightly from the first surface 442 of the second body 440.

[0118] Then, if through Figure 5 As indicated by the arrows of the thick double-dashed lines, the three screws s3 are screwed through the three through holes nh of the second body 440 and are completely fastened into the three threaded holes shb of the first body 420. Thus, the fixing device 400 is completed.

[0119] (g) Use of the fixing device 400

[0120] Fig.13 Is used to describe the use Figure 5 The fixture 400 in the embodiment of the present invention attaches the measuring head 1A to the Figure 3 912 of the first beam portion 910. When the measuring head 1A is attached to the frame body 900, first, the fixture 400 is attached to the attachment portion 919 of the first beam portion 910. Fig.13 , illustration of the first beam portion 910 is omitted.

[0121] When the fixture 400 is attached to the first beam portion 910, the distal end surfaces of the three protruding portions 431p and 432p of the first body 420 are pressed against the lower surface 912 ( Figure 3 ) on. In addition, the threaded hole sha formed in each of the protruding portions 431p and 432p is positioned so as to be aligned with the plurality of through holes 913 ( Figure 3 ) overlaps any one of the above. Then, the fixture 400 is screwed onto the lower surface 912.

[0122] Then, if Fig.13 As shown in the upper part of FIG. 1 , the ring member RB1 is attached to the portion near the rear end portion of the measuring head 1A (the portion near the optical fiber receptacle 30 or the portion near the optical fiber receptacle 30). The ring member RB1 includes a metal material such as stainless steel, and includes two semicircular arcuate members r1 and r2. Therefore, by sandwiching the portion near the rear end portion of the measuring head 1A with the two members r1 and r2 and connecting the two end portions of the members r1 and r2 with two screws s4 (see FIG. 1 ). Fig.13 The outer diameter of the ring member RB1 is larger than the maximum outer diameter of the head housing 10 of the measuring head 1A. Therefore, the ring member RB1 attached to the measuring head 1A serves as a flange of the measuring head 1A.

[0123] Then, if through Fig.13 As indicated by the thick solid arrow in FIG. 1 , in a state where the distal end portion FE of the measuring head 1A faces downward, the through hole 914 ( Figure 3 ) The measuring head 1A is inserted into the tubular portion 461 of the head holder 460. At this time, the lower surface of the ring member RB1 contacts one end portion 461a of the tubular portion 461 of the head holder 460. Thus, the measuring head 1A is supported by the head holder 460.

[0124] Next, if through Fig.13As indicated by the thick single-dot chain arrow in FIG. 4 , the screw s5 is attached to the clamping portion 462 b of the first tubular portion 462 and a portion of the outer circumferential surface of the measuring head 1A is fastened. Thus, the measuring head 1A is fastened by the first tubular portion 462 and held by the head holder 460 .

[0125] As described above, when the fixture 400 is assembled, Figure 5 None of the two fixing screws s1 in the first body 420 is completely tightened. Therefore, the head holder 460 is in a released state in the initial state. Therefore, the user can Figure 6 ) to adjust the position of the optical axis LA of the measuring head 1A.

[0126] Specifically, the user adjusts the two adjustment screws s2 ( Figure 5 ) in each of the first adjustment direction D1 and the second adjustment direction D2. Figure 4 as described.

[0127] In addition, after the position adjustment of the optical axis LA is completed, the user passes through the two through holes 445 ( Figure 8 ) Fully tighten (retighten) Figure 5 Thus, the head holder 460 is firmly screwed to the first body 420. That is, the head holder 460 is switched from the released state to the fixed state in which the head holder cannot move relative to the first body 420.

[0128] Here, in the fixing device 400, the rotation force blocking member 480 is located between the head of the fixing screw s1 and the head holder 460. In addition, as described above, in the state where the rotation force blocking member 480 is assembled into the second body 440, the corresponding screw receiving portion 481 is close to the first side forming portion 451 and the second side forming portion 452 or contacts the first side forming portion 451 and the second side forming portion 452. Therefore, the rotation force blocking member 480 is restricted to move or rotate in the horizontal plane by the first side forming portion 451 and the second side forming portion 452, and hardly moves and rotates relative to the second body 440. Therefore, when the fixing screw s1 is tightened, even if the head of the fixing screw s1 rotates in the state of contact with the rotation force blocking member 480, the rotation force blocking member 480 does not rotate. That is, the head of the fixing screw s1 slides on the rotation force blocking member 480 in the rotation direction of the fixing screw s1. Therefore, the rotational force generated at the head of the fixing screw s1 is not transmitted to the head holder 460 through the rotation force blocking member 480. In this manner, when the head holder 460 is switched from the released state to the fixed state, the rotational force of the fixing screw s1 does not act on the head holder 460. Therefore, when the fixing screw s1 is tightened, the head holder 460 is prevented from being displaced in an unintended direction relative to the first body 420.

[0129] Note that when it is desired to adjust the position of the optical axis LA again, the user loosens the tightening degree of each fixing screw s1. Therefore, the user can easily switch the head holder 460 from the fixed state to the released state.

[0130] (h) Proximity Arrangement of Multiple Fixing Devices 400 and Position Adjustment of Optical Axis LA

[0131] In the first beam portion 910 of the frame body 900, the plurality of attachment portions 919 are aligned to be substantially continuous. Therefore, in the case where the plurality of measuring heads 1A are attached to the plurality of attachment portions 919 so as to be continuously aligned, two adjacent fixtures 400 are in contact or close to each other. In the present embodiment, the interval between the two adjacent fixtures 400 is, for example, greater than 0 mm and less than or equal to 20 mm.

[0132] In this way, even when two fixtures 400 are aligned to be in contact or close to each other, the working efficiency of adjusting the position of the optical axis LA relative to each fixture 400 can be achieved using the configuration of the fixture 400 according to the present embodiment. This will be described.

[0133] Fig.14 The picture is close to Figure 3 The first beam portion 910 provides an external perspective view of the two fixtures 400, and Fig.15 It is a diagram showing the state of being cut by the horizontal virtual plane VS Fig.14 A horizontal cross-sectional view of two fixtures 400 in FIG. Fig.14 In the figure, the first beam portion 910 is omitted. Fig.14 and Fig.15 In the related description, in the case of distinguishing two fixtures 400 provided adjacent to each other, one fixture 400 is referred to as a first fixture 400A, and the other fixture 400 is referred to as a second fixture 400B.

[0134] In the fixing device 400 according to the present embodiment, two through holes 431h and 432h are respectively formed in the first end surface forming portion 431 and the second end surface forming portion 432 of the first body 420, as shown in FIG. Figure 6 and 7 These through holes 431h and 432h serve as passages for adjustment screws s2 provided in one fixture 400 by internal operation of the other fixture 400 when the two fixtures 400 are aligned close to each other in the y direction.

[0135] For example, in Fig.14 and Fig.15 In the example of FIG. 4 , one of the two through holes 432h formed in the second end surface forming portion 432 of the second fixture 400B extends from the end surface of the second end surface forming portion 432 facing the −x direction toward the first wall portion w1 of the first fixture 400A. Fig.14 and Fig.15 As indicated by arrow a01 in FIG. 4 , the user may insert a tool such as a screwdriver or a wrench into a through hole 432h of the second fixture 400B to operate an adjustment screw s2 of the first fixture 400A.

[0136] In addition, one of the two through holes 431h formed in the first end surface forming portion 431 of the second fixture 400B extends from the end surface of the first end surface forming portion 431 facing the +x direction toward the third wall portion w3 of the first fixture 400A. Fig.14 and Fig.15 As indicated by arrow A02 in FIG. 4 , the user may insert a tool such as a screwdriver or a wrench into one through hole 431h of the second fixture 400B to operate another adjustment screw s2 of the first fixture 400A.

[0137] Note that, in each fixture 400, the two through holes 431h formed in the first end surface forming portion 431 are formed so as to be symmetrical with respect to a straight line passing through the center of the fixture 400 along the longitudinal direction of the fixture 400 in a plan view. In addition, the two through holes 432h formed in the second end surface forming portion 432 are also formed so as to be symmetrical with respect to a straight line passing through the center of the fixture 400 along the longitudinal direction of the fixture 400 in a plan view.

[0138] Therefore, in Fig.14 and Fig.15 In the example, even in a case where the new fixture 400 is provided in the +y direction of the second fixture 400B and the two adjustment screws s2 of the fixture 400 face in the -y direction, the user can operate the two adjustment screws s2 of the new fixture 400 by inserting a tool into another through hole 431h and another through hole 432h of the second fixture 400B.

[0139] 4. Details of the Fixing Device 500

[0140] Will describe Figure 2 Details of the fixing device 500 in FIG. Fig.16 is provided in Figure 2 An exploded perspective view of the fixing device 500 on the second beam portion 920 in FIG. Fig.16 In the figure, arrows indicating the x-direction, y-direction, and z-direction orthogonal to each other are attached to clarify the following. Figure 5 The positional relationship between the multiple component elements of the fixture 500 in the example of . In addition, in the x direction, the direction in which the arrow x is oriented in the drawings is appropriately referred to as the +x direction, and its opposite direction is appropriately referred to as the -x direction in the following description. In addition, in the y direction, the direction in which the arrow y is oriented in the drawings is appropriately referred to as the +y direction, and its opposite direction is appropriately referred to as the -y direction. In addition, in the z direction, the direction in which the arrow z is oriented in the drawings is appropriately referred to as the +z direction, and its opposite direction is appropriately referred to as the -z direction.

[0141] like Fig.16As shown, the fixture 500 mainly includes a base portion 510 and a retaining member 550. The base portion 510 is a single member including a metal material such as stainless steel, and has a generally rectangular parallelepiped shape that is slightly longer in the x direction. A head opening 519 that runs through the center portion of the base portion 510 in the z direction is formed in the base portion 510. The head opening 519 is formed in a generally elliptical shape with a major axis in the x direction to such an extent that the measuring head 1B can be inserted and the inserted measuring head 1B can move a small distance in the x direction. In addition, the portion of the inner circumferential surface of the head opening 519 that faces the +x direction is formed in a semi-cylindrical shape extending in the z direction. In the following description, the portion of the inner circumferential surface of the head opening 519 that faces the +x direction is referred to as a head contact surface 519s.

[0142] In addition, the base portion 510 includes a supporting surface 511 and a supported surface 513 facing opposite directions to each other in the z direction. The supporting surface 511 includes a first supporting surface 511a and a second supporting surface 511b facing the +z direction and aligned in the x direction. Both the first supporting surface 511a and the second supporting surface 511b are flat surfaces orthogonal to the z direction, but at different height positions in the z direction. The first supporting surface 511a is located in the +z direction relative to the second supporting surface 511b. Therefore, between the first supporting surface 511a and the second supporting surface 511b, two step portions 512 are formed at the two end portions in the y direction. The threaded holes for connecting the retaining member 550 to be described later are formed in these step portions 512.

[0143] Three attachment portions 515 are formed on the supported surface 513 facing the -z direction, the three attachment portions 515 are separated from each other, and slightly protrude from another portion of the supported surface 513 in the -z direction. Each attachment portion 515 is formed with an attachment portion 929 (see Figure 3 The distal end surfaces of the three attachment portions 515 are formed so as to be located in a common plane orthogonal to the z-direction.

[0144] The retainer 550 is a generally rectangular plate-shaped member having a thickness corresponding to the step portion 512 of the base portion 510 and formed to extend in one direction. In addition, the retainer 550 is configured to be placed on the second support surface 511b of the base portion 510. The center of the side portion constituting one long side of the retainer 550 is cut into an arc shape. Therefore, the retainer 550 has a concave surface 550s corresponding to the head contact surface 519s of the head opening 519. When the retainer 550 is observed in the z direction, the concave surface 550s is bent in an arc shape and has a curvature radius that is the same or approximately the same as the head contact surface 519s. In addition, in the retainer 550, two through holes extending in the lateral direction are formed near the two end portions of the retainer 550 in the longitudinal direction. These through holes correspond to two threaded holes formed in the two step portions 512 of the base portion 510.

[0145] When assembling the fixture 500, the holder 550 is placed on the second supporting surface 511b of the base portion 510 so that the concave surface 550s of the holder 550 faces the head contact surface 519s of the base portion 510. In this state, the first surface of the holder 550 matches the height position of the first supporting surface 511a of the base portion 510 in the z direction.

[0146] In addition, two screws s10 are screwed through the two through holes of the holder 550 and temporarily fastened into the threaded holes of the two step portions 512 of the base portion 510. Thus, the fixing device 500 is completed.

[0147] Fig.17 Is used to describe the use Fig.16 The fixture 500 in the embodiment attaches the measuring head 1B to the Figure 3 921 of the second beam portion 920. When the measuring head 1B is attached to the frame body 900, first, the fixture 500 is attached to the attachment portion 929 of the second beam portion 920. Fig.17 , illustration of the second beam portion 920 is omitted.

[0148] When the fixture 500 is attached to the second beam portion 920, the distal end surfaces of the three attachment portions 515 of the supported surface 513 of the base portion 510 are pressed against the upper surface 921 ( Figure 3 ). In addition, the threaded hole formed in each of the three attachment portions 515 is positioned so as to be aligned with the plurality of through holes 923 ( Figure 3 ) overlaps any one of the above. Then, the fixture 500 is screwed onto the upper surface 921.

[0149] Then, if Fig.17The annular member RB2 is prepared as shown in the upper part of . The annular member RB2 includes a metal material such as stainless steel and has a slit in a portion in the circumferential direction. In addition, the annular member RB2 is formed with a dimensional tolerance relative to the assembly level of the measuring head 1B so that the measuring head 1B can be attached (assembled) to the annular member RB2.

[0150] Next, if through Fig.17 As indicated by the thick dashed arrow in FIG. 1 , the prepared annular member RB2 is attached to the portion near the distal end portion FE of the measuring head 1B. This attachment work is performed by temporarily elastically deforming the annular member RB2. The outer diameter of the annular member RB2 is larger than the maximum outer diameter of the head housing 10 of the measuring head 1B. Therefore, the annular member RB2 attached to the measuring head 1B serves as a flange of the measuring head 1B.

[0151] Next, if through Fig.17 As indicated by the thick solid arrow in FIG. 5 , the measuring head 1B is inserted into the head opening 519 of the base portion 510 with the distal end portion FE of the measuring head 1B facing upward. At this time, the lower surface of the annular member RB2 abuts against the first support surface 511a of the base portion 510 and the first surface of the holder 550. Therefore, the measuring head 1B is supported by the fixture 500.

[0152] Next, two screws s10 screwed into the threaded holes of the two step portions 512 of the base portion 510 through the two through holes of the holder 550 are completely tightened. As a result, a portion of the outer circumferential surface of the measuring head 1B is clamped on the head contact surface 519s ( Fig.16 ) and the concave surface 550s ( Fig.16 Note that the fixture 400 does not have a function of adjusting the optical axis position of the measuring head 1B, unlike the fixture 500.

[0153] 5. Preferred configuration for measuring the thickness of the measurement object S

[0154] (a) When the temperature environment changes while measuring the thickness of the measurement object S using the confocal displacement sensor 9, the measurement accuracy is likely to decrease due to expansion or contraction of each of the constituent elements (frame body 900, fixture 400, fixture 500, etc.).

[0155] In order to suppress the reduction of measurement accuracy, it is conceivable to use a material that does not expand or contract due to temperature changes to form each component element. However, such a material does not exist, or if it does, such a material is expensive and is hardly considered to be used in the above-mentioned component elements. In addition, in order to suppress the reduction of measurement accuracy, it is conceivable to form multiple component elements with multiple types of materials having different linear expansion coefficients, and offset the shape changes between the multiple component elements when the temperature environment changes. However, it is very difficult to set the shapes and sizes of multiple component elements and select the materials of multiple component elements when such an effect is desired.

[0156] In addition to the above, in order to suppress the reduction of measurement accuracy, it is conceivable to perform a correction process on the measurement data according to the expansion or contraction of each component element caused by the change of the temperature environment. In this case, the appropriate conditions for the correction process can be determined, for example, based on the estimation result obtained by estimating the change of the holding state (holding position, etc.) of the measuring heads 1A and 1B caused by the change of the temperature environment. However, when the materials used are different between a plurality of component elements, it is necessary to consider the difference in the amount of expansion or contraction that occurs between the plurality of component elements. Therefore, it is difficult to grasp the change of the holding state (holding position, etc.) of the measuring heads 1A and 1B caused by the change of the temperature environment. Therefore, when a method for performing a correction process on the measurement data is adopted, it is preferred that the various components used for the thickness measurement of the measuring object S include the same metal material as much as possible.

[0157] Specifically, the base housing 410, the head holder 460, the rotational force blocking member 480, the spring sp and the plurality of screws (s1, s2 and s3) constituting the fixture 400 preferably include a common metal material (e.g., stainless steel). In addition, the base portion 510, the retainer 550 and the plurality of screws s10 constituting the fixture 500 also preferably include a common metal material (e.g., stainless steel). In addition, the annular members RB1 and Rb2 and the screws s10 attached to the measuring heads 1A and 1B also preferably include a common metal material (e.g., stainless steel). In addition, it is preferred that the frame body 900 and the screws attached to the frame body 900 also include a common metal material (e.g., stainless steel).

[0158] In these cases, since a large number of constituent elements used for thickness measurement of the measuring object S include a common metal material, it is easy to grasp changes in the holding state (holding position, etc.) of the measuring heads 1A and 1B due to changes in the temperature environment. Therefore, appropriate correction processing can be performed on the measurement data based on errors predicted to occur in advance by simulation, etc.

[0159] (b) The measuring heads 1A and 1B have a configuration in which a plurality of lenses 221, 222, 223, and 224 are accommodated in a head housing 10. Here, the head housing 10 of each of the measuring heads 1A and 1B expands or contracts according to changes in the temperature environment. In addition, the optical characteristics (focal length, etc.) of each of the plurality of lenses 221, 222, 223, and 224 change according to changes in the temperature environment. Therefore, in the case where the temperature characteristics of the head housing 10 and the temperature characteristics of the plurality of lenses 221, 222, 223, and 224 are known in advance, the measuring heads 1A and 1B can be designed so that an expected measurement error occurs according to changes in the temperature environment based on the known information.

[0160] So, for example, in Figure 4 During thickness measurement of the measuring object S in FIG. 1 , when the holding positions of the measuring heads 1A and 1B by the frame body 900 and the fixtures 400 and 500 change as the temperature environment changes, the measuring heads 1A and 1B are preferably configured so that the measurement error caused by the change in the holding position is offset.

[0161] That is, it is preferable to design the head housing 10 and the optical system (221 to 224) of each of the measuring heads 1A and 1B so that the measurement error occurring due to the temperature characteristics thereof cancels the measurement error caused by the temperature characteristics of the frame body 900 for thickness measurement and the fixtures 400 and 500. In this case, even when the temperature environment changes during the thickness measurement of the measuring object S, the thickness of the measuring object S can be measured with high accuracy without requiring correction processing that takes into account the change in the temperature environment.

[0162] 6. Matching degree communication function

[0163] The confocal displacement sensor 9 according to the present embodiment has a matching degree communication function. The matching degree communication function includes determining a matching degree indicating how much the optical axes of the two measuring heads 1A and 1B used for thickness measurement of the measuring object S match in response to a user's operation of the operating unit 4b or a request from an external device. In addition, the matching degree communication function includes sending a matching degree determination result to a predetermined external device.

[0164] In this case, for example, the user can display the matching degree determination result received by the external device on a display device other than the main display unit 4a and the sub-display unit 190. Examples of the external device include a programmable logic controller (PLC), a control panel, and a tablet terminal that can be carried by the user. Therefore, the user can arrange another display device near the measuring heads 1A and 1B, and adjust the position of the optical axis LA of the measuring head 1A relative to the measuring head 1B while visually recognizing the matching degree displayed on the display device.

[0165] Figure 1 The memory 3b in the memory stores a matching degree communication program corresponding to the matching degree communication function. Figure 1 The CPU 3a in the processor executes the matching degree communication program stored in the memory 3b to implement a plurality of functional units for the matching degree communication function.

[0166] Fig.18 is a block diagram illustrating a functional configuration implemented in the PC 3 by executing the matching degree communication program. Fig.18 As shown, the PC 3 includes a command receiving unit fb1, a matching degree determining unit fb2, and an information communication unit fb3 as functional units corresponding to the matching degree communication function. Note that some or all of these functional units may be configured by hardware such as electronic circuits.

[0167] The command receiving unit fb1 receives a command signal indicating the use of the matching degree communication function. When the user operates the operation unit 4b, the command signal is supplied to the command receiving unit fb1. Alternatively, the command signal is supplied to the command receiving unit fb1 from the external device 600 of the confocal displacement sensor 9.

[0168] When receiving a command signal instructing to use the matching degree communication function, the command receiving unit fb1 gives the control unit 2 a measurement condition for determining the matching degree between the optical axes of the two measuring heads 1A and 1B. In this case, the control unit 2 gives the measurement control unit 150 ( Figure 1 ) given the given measurement conditions.

[0169] Therefore, the confocal displacement sensor 9 is transformed into a state in which, for example, light is emitted from one measuring head 1A (or measuring head 1B) and light is not emitted from the other measuring head 1B (or measuring head 1A). In this case, when the degree of matching of the optical axes is high, the intensity of light emitted from the measuring head 1A (or measuring head 1B) and incident on the measuring unit 100B (or measuring unit 100A) through the measuring head 1B (or measuring head 1A) increases. Therefore, the light receiving signal output from the measuring unit 100B (or measuring unit 100A) is provided to the control unit 2. The control unit 2 gives a given light receiving signal to the PC 3.

[0170] In the PC 3, the matching degree determination unit fb2 determines the matching degree of the optical axes of the measuring heads 1A and 1B based on the light reception signal given from the control unit 2. The information communication unit fb3 transmits the matching degree determination result to a predetermined external device 600. Note that when a command signal instructing to use the matching degree communication function is given to the command receiving unit fb1, the transmission destination of the matching degree determination result may be given to the command receiving unit fb1 as accompanying information of the command signal. In this case, the information communication unit fb3 transmits the matching degree determination result only to the external device 600 designated as the transmission destination based on the accompanying information given to the command receiving unit fb1.

[0171] Fig.19 1 is a flow chart of the matching degree communication process based on the matching degree communication program. For example, when the confocal displacement sensor 9 is powered on, the matching degree communication process is repeated at a predetermined cycle. Fig.19 As shown, first, Fig.18 The command receiving unit fb1 in the control unit 2 determines whether a command signal instructing to use the matching degree communication function has been received by the user's operation of the operation unit 4b or the communication from the external device 600 (step S101). When the command signal is not received, the command receiving unit fb1 repeats the processing of step S101. On the other hand, when the command signal is received, the command receiving unit fb1 gives the control unit 2 a measurement condition for determining the matching degree of the optical axis (step S102).

[0172] Next, the matching degree determination unit fb2 determines whether a light receiving signal is given from one of the measuring units 100A and 100B (step S103). When no light receiving signal is given, the matching degree determination unit fb2 repeats the process of step S103. On the other hand, when a light receiving signal is given, the matching degree determination unit fb2 determines the matching degree based on the light receiving signal (step S104). The matching degree determination can be performed based on whether the intensity of a given light receiving signal exceeds a predetermined threshold value, or can be performed based on any one of a plurality of intensity ranges pre-divided into levels to which the intensity of a given light receiving signal belongs. Thereafter, the information communication unit fb3 sends the matching degree determination result to a predetermined external device 600 (step S105). Therefore, the matching degree communication process ends.

[0173] According to the matching degree communication function, the user can perform alignment work of the optical axis between the two measuring heads 1A and 1B while displaying the matching degree determination result sent to the external device 600 on the display device. This makes it possible to align the optical axis with high accuracy while improving work efficiency.

[0174] According to the matching degree communication function, the following operation is also possible. For example, it is assumed that a plurality of sheet-like measuring objects S are intermittently measured. Specifically, it is assumed that one measuring object S is arranged between the measuring heads 1A and 1B and undergoes thickness measurement, and then, the one measuring object S is removed from between the measuring heads 1A and 1B. It is assumed that the next measuring object S is then arranged between the measuring heads 1A and 1B and undergoes thickness measurement.

[0175] When such an operation is repeated, there is a moment when the measuring object S does not exist between the measuring heads 1A and 1B. Therefore, the matching degree communication function is used at the moment when the measuring object S does not exist between the measuring heads 1A and 1B. In this case, the matching degree is transmitted to the external device 600 whenever the thickness measurement of the measuring object S is performed. Therefore, the transmitted matching degree is displayed on a desired display device, and therefore, whenever the thickness measurement of the measuring object S is performed, the user can confirm the misalignment of the optical axis between the measuring heads 1A and 1B.

[0176] 7. Effect

[0177] (a) The fixture 400 according to the present embodiment may be arranged to be aligned in a predetermined alignment direction (in the above example, the y direction) together with a plurality of other fixtures 400 having the same configuration as the fixture 400. Here, the directions (the first adjustment direction D1 and the second adjustment direction D2) of position adjustment of the optical axis LA of the measuring head 1A attached to the frame body 900 using the fixture 400 intersect with the alignment direction and do not coincide with the alignment direction.

[0178] Therefore, when it is desired to adjust the position of the optical axis LA of the measuring head 1A for each of the plurality of aligned fixtures 400, the user does not need to approach the fixture 400 along the alignment direction. Therefore, it is not necessary to provide a work space for position adjustment of the optical axis LA of the measuring head 1A performed by the user between the plurality of fixtures 400 in the alignment direction. Therefore, it is possible to arrange the plurality of optical axes LA of the plurality of measuring heads 1A at a higher density while achieving position adjustment of the optical axis LA for each of the plurality of measuring heads 1A.

[0179] (b) Two threaded holes shc for screwing two adjustment screws s2 into the first side surface forming portion 451 of the plate-like portion 441 are formed in the above-mentioned fixture 400. On the other hand, two spring accommodating portions sf for accommodating two springs sp are formed in the second side surface forming portion 452 of the plate-like portion 441. That is, in the fixture 400, the two adjustment screws s2 are provided on one side surface portion formed by the first side surface forming portion 451. Therefore, in the fixture 400, it is possible to adjust the two adjustment screws s2 from a position in a direction oriented by one side surface portion formed by the first side surface forming portion 451 (in Figure 4 In the example, two adjustment screws s2 are operated in the position in the +y direction).

[0180] (c) In the fixture 400, the head holder 460 in the released state is biased toward the first wall portion w1 by the spring sp provided on the second wall portion w2. When the position of the optical axis LA is adjusted in this state, for example, the adjustment screw s2 is screwed from the threaded hole shc formed in the first wall portion w1. Therefore, the head holder 460 is pressed by the distal end portion of the screwed adjustment screw s2 and moves in the first adjustment direction D1 against the biasing force of the spring sp of the second wall portion w2.

[0181] In addition, the head holder 460 in the released state is biased toward the third wall portion w3 by the spring sp provided on the fourth wall portion w4. When the position of the optical axis LA is adjusted in this state, for example, the adjustment screw s2 is screwed from the threaded hole shc formed in the third wall portion w3. Therefore, the head holder 460 is pressed by the distal end portion of the screwed adjustment screw s2 and moves in the second adjustment direction D2 against the biasing force of the spring sp of the fourth wall portion w4.

[0182] As described above, the biasing force by the two springs sp provided on the second wall portion w2 and the fourth wall portion w4 always acts on the head holder 460 in the released state. This facilitates the positioning work of the optical axis LA when adjusting the position of the optical axis LA of the measuring head 1A.

[0183] (d) As described above, the tubular portion 461 of the head holder 460 has the first tubular portion 462 and the second tubular portion 463, and the notch cc extending in the circumferential direction by a predetermined distance is formed between the first tubular portion 462 and the second tubular portion 463. With such a configuration, when the measuring head 1A is fastened by the first tubular portion 462, even if a twisting deformation caused by the fastening occurs in the first tubular portion 462, due to the notch cc, the twisting deformation is less likely to be transmitted to the second tubular portion 463. Therefore, the first tubular portion 462 is prevented from being supported by the base housing 410 in a posture deviating from a predetermined posture due to the twisting deformation occurring in the first tubular portion 462.

[0184] (e) The first body 420 of the fixing device 400 is configured using a single member. In addition, the first body 420 has the distal end surfaces of the three protruding portions 431 p as an attachment surface to be attached to the lower surface 912 of the first beam portion 910 .

[0185] In this case, since the first body 420 is configured using a single member, the distal end surfaces of the three protruding portions 431p are attached to the lower surface 912 of the first beam portion 910, whereby the first surface 422 of the first body 420 is in a constant positional relationship with the lower surface 912 of the first beam portion 910. Therefore, since the head holder 460 maintains a constant positional relationship with respect to the lower surface 912 of the first beam portion 910, the measurement accuracy of the physical quantity by the measuring head 1A is improved.

[0186] 8. Other embodiments

[0187] (a) In the fixing device 400 of the above-mentioned embodiment, the threaded holes shc are respectively formed in the first wall portion w1 and the third wall portion w3, and the spring receiving portions sf are respectively formed in the second wall portion w2 and the fourth wall portion w4, but the present invention is not limited thereto. The threaded holes shc may be formed in each of the first wall portion w1 and the fourth wall portion w4, and the spring receiving portions sf may be formed in each of the third wall portion w3 and the fourth wall portion w4.

[0188] (b) In the fixing device 400 according to the above embodiment, the metal spring sp is used to bias the head holder 460 toward the first wall portion w1 and the head holder 460 toward the third wall portion w3, but the present invention is not limited thereto. As a configuration for biasing the head holder 460 toward the first wall portion w1 and the third wall portion w3, a spring made of resin may be used instead of the spring sp made of metal, or other elastic bodies such as rubber may be used.

[0189] (c) Although in the above-described embodiment, only one of the two measuring heads 1A and 1B for measuring the thickness of the measuring object S may be attached to the frame body 900 by the fixture 400 so as to adjust the position of the optical axis LA, the present invention is not limited thereto. Both of the two measuring heads 1A and 1B for measuring the thickness of the measuring object S may be attached to the frame body 900 by the fixture 400. In this case, the measuring head 1A is attached to the attachment portion 919 of the first beam portion 910 by the fixture 400, and the measuring head 1B is attached to the attachment portion 929 of the second beam portion 920 by the fixture 400.

[0190] (d) Although the measuring heads 1A and 1B according to the above embodiments are measuring heads for confocal displacement sensors, the present invention is not limited thereto. The measuring head attached to the mounting surface by the fixture 400 may be a measuring head for a laser displacement sensor or a non-contact optical thermometer.

[0191] (e) Although the frame body 900 according to the above-described embodiment is configured using a single member, the present invention is not limited thereto. The frame body 900 may have a configuration in which a plurality of members are coupled. Note that in this case, the plurality of members constituting the frame body 900 preferably include a common material. In addition, the frame body 900 according to the above-described embodiment has a shape (square or rectangular) formed by the first to fourth sides when the first beam portion 910 is the first side, the second beam portion 920 is the second side, and the two column portions 930 are the third side and the fourth side, respectively, but the present invention is not limited thereto. The frame body 900 may have a shape (C-shaped or U-shaped) including a first beam portion 910, a second beam portion 920, and a column portion 930.

[0192] (f) In the above-described embodiment, the plurality of fixtures 400 attached to the first beam portion 910 of the frame body 900 are aligned in the y direction in a state where the first side surface forming portion 451 of the corresponding fixture 400 faces the +y direction and the second side surface forming portion 452 faces the -y direction. The plurality of fixtures 400 may be aligned in the y direction in a state where the first side surface forming portion 451 faces the -y direction and the second side surface forming portion 452 faces the +y direction in at least some of the plurality of fixtures 400.

[0193] 9. Correspondence between each component element of the claims and each unit of the embodiments

[0194] Hereinafter, an example of the correspondence relationship between each constituent element of the claims and each unit of the embodiment will be described, but the present invention is not limited to the following examples. Various other elements having the configuration or function described in the claims may be used as the corresponding constituent elements of the claims.

[0195] In the above-mentioned embodiment, the optical axis LA is an example of an optical axis, the measuring heads 1A and 1B are examples of measuring heads, the lower surface 912 of the frame body 900 is an example of a mounting surface, the fixture 400 is an example of a fixture, the head holder 460 is an example of a head holder, the first surface 422 of the first body 420 of the base shell 410 is an example of a first surface and a support surface, and the base shell 410 is an example of a base shell.

[0196] In addition, the posture of the fixture 400 arranged on the lower surface 912 of the first beam portion 910 such that the first side surface forming portion 451 and the second side surface forming portion 452 are aligned along the Y direction is an example of a common posture.

[0197] In addition, the first adjustment direction D1 is an example of a first adjustment direction, the second adjustment direction D2 is an example of a second adjustment direction, the two adjustment screws S2 are examples of a first adjustment screw and a second adjustment screw, the fixing screw S1 is an example of a switching part and a fixing screw, and the Y direction in which the first beam part 910 of the frame body 900 extends is an example of an alignment direction.

[0198] In addition, the side surface formed by the first side surface forming portion 451 is an example of a first side surface, the side surface formed by the second side surface forming portion 452 is an example of a second side surface, the first wall portion w1 is an example of a first wall portion, the second wall portion w2 is an example of a second wall portion, the third wall portion w3 is an example of a third wall portion, and the fourth wall portion w4 is an example of a fourth wall portion.

[0199] In addition, the threaded hole shc formed in the first wall portion w1 is an example of a first threaded hole, the spring sp provided in the second wall portion w2 is an example of a first elastomer, the threaded hole shc formed in the third wall portion w3 is an example of a second threaded hole, and the spring sp provided in the fourth wall portion w4 is an example of a second elastomer.

[0200] In addition, the end surface formed by the second end surface forming portion 432 is an example of a first end surface, the end surface formed by the first end surface forming portion 431 is an example of a second end surface, the through hole 432h is an example of a first screw channel, the through hole 431h is an example of a second screw channel, the first body 420 is an example of a first body, the threaded hole 425 is an example of a fixed threaded hole, and the through hole 465 is an example of a through hole formed in the head holder.

[0201] In addition, the second body 440 is an example of a second body, the rotational force blocking member 480 is an example of a rotational force blocking member, the distal end surfaces of the protruding portions 431p and 432p are examples of attachment surfaces, the tubular portion 461 is an example of a tubular portion, the supported portions 464a to 464d are examples of supported portions, one end portion 461a is an example of a first end portion, the other end portion 461b is an example of a second end portion, the first tubular portion 462 is an example of a first tubular portion, and the second tubular portion 463 is an example of a second tubular portion.

[0202] In addition, the notch cc is an example of a notch, the measuring head 1A is an example of a first measuring head, the measuring head 1B is an example of a second measuring head, the first beam portion 910 is an example of a first beam portion, the second beam portion 920 is an example of a second beam portion, the column portion 930 is an example of a column portion, the frame body 900 is an example of a frame body, the lenses 221 to 224 are examples of an optical system, and the head case 10 is an example of an optical system holder. In addition, the matching degree determination unit fb2 is an example of a matching degree determination unit, the information communication unit fb3 is an example of an information communication unit, the external device 600 is an example of an external device, and the confocal displacement sensor 9 is an example of a displacement sensor device.

[0203] 10. Overview of Embodiments

[0204] (Item 1) The fixture according to Item 1 is a fixture configured to attach a measuring head to a mounting surface, the measuring head having an optical axis extending in one direction and acquiring a physical quantity related to a measurement object arranged on the optical axis, and the fixture includes:

[0205] a head holder, the head holder holding the measuring head;

[0206] a base housing configured to be attachable to the mounting surface and to movably support the head holder on a surface orthogonal to the optical axis of the measuring head held by the head holder;

[0207] a first adjustment screw that moves the head holder supported by the base housing on the one surface in a first adjustment direction;

[0208] a second adjustment screw that moves the head holder supported by the base housing on the one surface in a second adjustment direction different from the first adjustment direction; and

[0209] a switching portion that switches the state of the head holder supported by the base housing between a fixed state in which the head holder cannot move on the one surface and a released state in which the head holder can move on the one surface,

[0210] wherein the base housing is configured in such a manner that a plurality of base housings including the base housing are arranged to be aligned in a predetermined alignment direction in a common posture on the mounting surface, and

[0211] When the plurality of base housings are aligned in the alignment direction in the common posture on the mounting surface, each of the first adjustment direction and the second adjustment direction intersects the alignment direction.

[0212] In the fixture, the base shell enables a plurality of base shells including the base shell to be arranged to be aligned in a common posture in the predetermined alignment direction on the mounting surface. That is, the fixture can be arranged to be aligned in the alignment direction together with a plurality of other fixtures having the same configuration as the fixture. Here, each of the first adjustment direction and the second adjustment direction intersects with the alignment direction and does not coincide with the alignment direction.

[0213] In this case, when it is desired to adjust the position of the optical axis of the measuring head for each of the plurality of fixtures, the user does not need to approach the fixture along the alignment direction. Therefore, it is not necessary to provide a work space for position adjustment of the optical axis of the measuring head performed by the user between the plurality of fixtures in the alignment direction. Therefore, it is possible to arrange the plurality of optical axes of the plurality of measuring heads at a higher density while achieving position adjustment of the optical axis for each of the plurality of measuring heads.

[0214] (Item 2) In the fixing device according to Item 1, the base shell has a first side surface and a second side surface, and when the base shell is attached to the mounting surface, when viewed from a position facing the mounting surface, the first side surface and the second side surface are opposite to each other in the alignment direction, and the base shell can be configured in such a way that from either side surface of the first side surface and the second side surface, the first adjustment screw can be screwed in the first adjustment direction, and the second adjustment screw can be screwed in the second adjustment direction.

[0215] In this case, the first and second adjusting screws may be screwed into the base housing from positions in a direction in which one of the first and second side surfaces of the base housing is oriented.

[0216] (Item 3) In the fixing device according to item 1 or 2,

[0217] The base housing may include

[0218] a first wall portion and a second wall portion, the first wall portion and the second wall portion facing each other across the head holder in the first adjustment direction in a state where the head holder is supported by the base housing, and

[0219] a third wall portion and a fourth wall portion, which face each other across the head holder in the second adjustment direction in a state where the head holder is supported by the base housing,

[0220] A first threaded hole may be formed in the first wall portion, the first threaded hole extending in the first adjustment direction, and the first adjustment screw can be screwed into the first threaded hole,

[0221] The second wall portion may be provided with a first elastic body, the first elastic body biasing the head holder towards the first wall portion,

[0222] A second threaded hole may be formed in the third wall portion, the second threaded hole extending in the second adjustment direction, and the second adjustment screw can be screwed into the second threaded hole, and

[0223] The fourth wall portion may be provided with a second elastic body which biases the head holder toward the third wall portion.

[0224] In this case, the head holder in the released state is biased by the first elastic body from the second wall portion toward the first wall portion. In this state, when the first adjustment screw is screwed into the first threaded hole, the base body is pressed by the distal end portion of the first adjustment screw to overcome the biasing force of the first elastic body and move in the first adjustment direction.

[0225] In addition, the head holder in the released state is biased by the second elastic body from the fourth wall portion toward the third wall portion. In this state, when the second adjustment screw is screwed into the second threaded hole, the base body is pressed by the distal end portion of the second adjustment screw to overcome the biasing force of the second elastic body and move in the second adjustment direction.

[0226] As described above, the biasing force of the first elastic body and the second elastic body always acts on the base body in the released state, which helps the positioning work of the optical axis when adjusting the optical axis position of the measuring head.

[0227] (Item 4) In the fixture according to Item 3,

[0228] The base housing may have a first end surface and a second end surface, and the first end surface and the second end surface are opposite to each other in a direction orthogonal to the alignment direction when viewed from a position facing the mounting surface in a state where the base housing is attached to the mounting surface, and

[0229] A first screw channel and a second screw channel can be formed in the base shell, and when the multiple base shells are aligned close to each other in the alignment direction in the common posture on the mounting surface, the first screw channel extends from the first end surface toward the first wall portion of the base shell adjacent to the base shell, and the second screw channel extends from the second end surface toward the third wall portion of the base shell adjacent to the base shell.

[0230] According to the above configuration, when it is desired to adjust the position of the optical axis of the measuring head for each of a plurality of fixtures aligned close to each other in the alignment direction, the first adjustment screw can be operated through the first screw passage of the fixture adjacent to the fixture. In addition, the second adjustment screw can be operated through the second screw passage of the fixture adjacent to the fixture.

[0231] (Item 5) In the fixing device according to any one of Items 1 to 4,

[0232] The base housing may include a first body having a flat support surface forming the one surface and configured to be capable of supporting the head holder on the support surface,

[0233] A fixing threaded hole may be formed in the support surface, the fixing threaded hole opening toward the space on the support surface,

[0234] A through hole having an inner diameter larger than that of the fixing threaded hole may be formed in the head holder, and

[0235] The switching portion may include a fixing screw screwed into the fixing threaded hole through the through hole in a state where the head holder is supported on the supporting surface.

[0236] According to the above configuration, the head holder is put into a fixed state by tightening the fixing screw. On the other hand, the head holder is put into a released state by loosening the tightening degree of the fixing screw. In this way, the state of the head holder can be easily switched by operating the fixing screw.

[0237] (Item 6) The fixing device according to Item 5 further includes a rotation force blocking member provided between the head of the fixing screw and the head holder in a state in which the fixing screw is screwed into the fixing threaded hole of the first body through the through hole of the head holder,

[0238] wherein the base housing may include a second body attached to a support surface of the first body in a predetermined positional relationship across at least a portion of the head holder, and

[0239] The rotation force blocking member may be configured to be non-rotatable around an axis of the fixing screw by being in contact with the second body.

[0240] According to the above configuration, since the rotational force blocking member cannot rotate around the axis of the fixing screw, the rotational force generated at the head of the fixing screw when the fixing screw is tightened is not transmitted to the rotational force blocking member. Therefore, when the head holder is switched from the released state to the fixed state, the rotational force of the fixing screw does not act on the head holder. Therefore, when the fixing screw is tightened, the head holder is prevented from shifting in an unexpected direction relative to the first body.

[0241] (Item 7) In the fixing device according to Item 5 or 6, the first body may be configured using a single member, and have an attachment surface attached to the mounting surface.

[0242] In this case, since the first body is configured using a single member, the support surface is in a certain positional relationship with the mounting surface by attaching the attachment surface to the mounting surface. Therefore, since the head holder is maintained in a constant positional relationship with respect to the mounting surface, the measurement accuracy of the physical quantity by the measuring head is improved.

[0243] (Item 8) In the fixing device according to any one of Items 1 to 7,

[0244] The measuring head may have a tubular shape extending along the optical axis,

[0245] The head holder may include

[0246] a tubular portion into which the measuring head can be inserted, and

[0247] a supported portion, the supported portion being supported by the base housing,

[0248] The tubular portion may have a first end portion and a second end portion, and have the first tubular portion and the second tubular portion aligned in sequence from the first end portion toward the second end portion,

[0249] A notch extending a certain distance in the circumferential direction of the tubular portion may be formed between the first tubular member and the second tubular member in the tubular portion,

[0250] The first tubular portion may be configured to be capable of holding the measuring head by tightening an outer circumferential portion of the measuring head in a state where the measuring head is inserted, and

[0251] The supported portion may be provided on an outer circumferential portion of the second tubular portion in such a manner that the head holder is supported by the base housing in a predetermined posture.

[0252] In this case, when the first tubular part tightens the outer circumference of the measuring head, the measuring head is held by the head holder in a state where the measuring head is inserted into the tubular part. In this state, distortion caused by tightening the outer circumference of the measuring head is likely to occur in the first tubular part of the tubular part.

[0253] Even in this case, since the notch is formed between the first tubular portion and the second tubular portion in the tubular portion according to the above configuration, the twisting deformation occurring in the first tubular portion is less likely to be transmitted to the second tubular portion. Therefore, the head holder is prevented from being supported by the base housing in a posture deviating from a predetermined posture due to the deformation occurring in the first tubular portion.

[0254] (Item 9) In the fixing device according to any one of Items 1 to 8, the head holder, the base housing, the first adjustment screw, the second adjustment screw, and the switching portion may include a common metal material.

[0255] In this case, since the respective constituent elements of the fixture include a common metal material, it is easy to grasp the change in the holding state of the measuring head due to the change in the temperature environment.

[0256] (Item 10) In the fixing device according to any one of Items 1 to 9,

[0257] The measuring head may be a displacement sensor, which acquires the distance from the measuring head to the measuring object arranged on the optical axis as the physical quantity.

[0258] By arranging a pair of measuring heads as a first measuring head and a second measuring head to face each other on one axis across the measuring object, the thickness of the measuring object can be measured.

[0259] A frame body can be used to measure the thickness of the measurement object, the frame body including a first beam portion to which the first measurement head is attached, a second beam portion to which the second measurement head is attached, and a column portion coupling the first beam portion and the second beam portion, and

[0260] The fixture is used for at least one of attaching the first measuring head to the mounting surface of the first beam portion and attaching the second measuring head to the mounting surface of the second beam portion, and comprises the same material as the frame body.

[0261] According to the above configuration, the fixing means for attaching at least one of the first measuring head and the second measuring head to the frame body includes the same material as the frame body. This makes it easy to grasp the change in the distance between the first measuring head and the second measuring head due to the change in the temperature environment. Therefore, when measuring the thickness of the measurement object, arithmetic processing such as correction according to the change in the temperature environment becomes easy.

[0262] (Item 11) The measuring head according to Item 11 is a measuring head attached to the fixture according to Item 10 as the first measuring head or the second measuring head, and includes an optical system holder that holds an optical system corresponding to the optical axis,

[0263] The optical system and the optical system holder are configured to offset errors in the result of the thickness measurement of the measuring object caused by changes in the holding position of the measuring head held by the frame body and the fixing device during measurement of the thickness of the measuring object using the frame body, when the holding position of the measuring head held by the frame body and the fixing device on the optical axis changes with changes in the temperature environment.

[0264] According to the above configuration, even when the temperature environment changes, the thickness of the measurement object can be measured with high accuracy without requiring correction processing or the like that takes into account the change in the temperature environment.

[0265] (Item 12) The displacement sensor device according to Item 12 comprises:

[0266] The first measuring head according to item 10;

[0267] A second measuring head according to item 10;

[0268] a matching degree determining unit that determines a matching degree indicating how much an optical axis of the first measuring head matches an optical axis of the second measuring head based on an intensity of light emitted from one of the first measuring head and the second measuring head and incident on the other measuring head in a state where the first measuring head and the second measuring head are arranged to face each other; and

[0269] An information communication unit transmits the matching degree determination result obtained by the matching degree determination unit to a predetermined external device.

[0270] In this case, the user can cause the display device to display the matching degree determination result transmitted to the external device. Therefore, the user can perform the alignment work of the optical axis between the first measuring head and the second measuring head in the preparation stage of measuring the thickness of the measurement object using the first measuring head and the second measuring head, while visually recognizing the matching degree determination result. Therefore, the efficiency of the optical axis alignment work is improved. In addition, the optical axis alignment can be performed with high accuracy.

Claims

1. A fixture configured to attach a measuring head to a mounting surface, the measuring head having an optical axis extending in one direction and the measuring head acquiring a physical quantity related to a measurement object arranged on the optical axis, the fixture comprising: a head holder, the head holder holding the measuring head; a base housing configured to be attachable to the mounting surface and to movably support the head holder on a surface that is orthogonal to the optical axis of the measuring head held by the head holder; a first adjustment screw that moves the head holder supported by the base housing on the one surface in a first adjustment direction; a second adjustment screw that moves the head holder supported by the base housing on the one surface in a second adjustment direction different from the first adjustment direction; as well as a switching portion that switches the state of the head holder supported by the base housing between a fixed state in which the head holder cannot move on the one surface and a released state in which the head holder can move on the one surface, wherein the base housing is configured in such a manner that a plurality of base housings including the base housing are arranged to be aligned in a predetermined alignment direction in a common posture on the mounting surface, and When the plurality of base housings are aligned in the alignment direction in the common posture on the mounting surface, each of the first adjustment direction and the second adjustment direction intersects the alignment direction.

2. The fixing device according to claim 1, wherein the base shell has a first side surface and a second side surface, and when the base shell is attached to the mounting surface, when viewed from a position facing the mounting surface, the first side surface and the second side surface are opposite to each other in the alignment direction, and the base shell is configured in such a way that from either side surface of the first side surface and the second side surface, the first adjustment screw can be screwed in the first adjustment direction, and the second adjustment screw can be screwed in the second adjustment direction.

3. The fixing device according to claim 1 or 2, wherein the base housing includes a first wall portion and a second wall portion, the first wall portion and the second wall portion facing each other across the head holder in the first adjustment direction in a state where the head holder is supported by the base housing, and the base housing including a third wall portion and a fourth wall portion, the third wall portion and the fourth wall portion facing each other across the head holder in the second adjustment direction in a state where the head holder is supported by the base housing, A first threaded hole is formed in the first wall portion, the first threaded hole extending in the first adjustment direction, and the first adjustment screw can be screwed into the first threaded hole, The second wall portion is provided with a first elastic body, which biases the head holder toward the first wall portion, A second threaded hole is formed in the third wall portion, the second threaded hole extending in the second adjustment direction, and the second adjustment screw can be screwed into the second threaded hole, and The fourth wall portion is provided with a second elastic body which biases the head holder toward the third wall portion.

4. The fixing device according to claim 3, wherein The base housing has a first end surface and a second end surface, and when viewed from a position facing the mounting surface in a state where the base housing is attached to the mounting surface, the first end surface and the second end surface are opposed to each other in a direction orthogonal to the alignment direction, and A first screw channel and a second screw channel are formed in the base shell, and when the multiple base shells are aligned close to each other in the alignment direction in the common posture on the mounting surface, the first screw channel extends from the first end surface toward the first wall portion of the base shell adjacent to the base shell, and the second screw channel extends from the second end surface toward the third wall portion of the base shell adjacent to the base shell.

5. The fixing device according to claim 1 or 2, wherein The base housing includes a first body having a flat support surface forming the one surface and configured to be capable of supporting the head holder on the support surface, a fixing threaded hole formed in the support surface, the fixing threaded hole opening toward the space on the support surface, A through hole having an inner diameter larger than that of the fixing threaded hole is formed in the head holder, and The switching portion includes a fixing screw that is screwed into the fixing threaded hole through the through hole in a state in which the head holder is supported on the supporting surface.

6. The fixing device according to claim 5, further comprising a rotation force blocking member, which is provided between the head of the fixing screw and the head holder in a state where the fixing screw is screwed into the fixing threaded hole of the first body through the through hole of the head holder, wherein the base housing includes a second body attached to a support surface of the first body across at least a portion of the head holder in a predetermined positional relationship, and The rotation force blocking member is configured not to rotate around an axis of the fixing screw by being in contact with the second body. 7 . The fixing device according to claim 5 , wherein the first body is configured using a single member and has an attachment surface attached to the mounting surface.

8. The fixing device according to claim 1 or 2, wherein The measuring head has a tubular shape extending along the optical axis, The head holder comprises a tubular portion into which the measuring head can be inserted, and The head holder includes a supported portion supported by the base housing, The tubular portion has a first end portion and a second end portion, and the tubular portion has the first tubular portion and the second tubular portion aligned in sequence from the first end portion toward the second end portion, a notch extending a certain distance in the circumferential direction of the tubular portion, formed between the first tubular member and the second tubular member in the tubular portion, The first tubular portion is configured to be capable of holding the measuring head by tightening an outer circumferential portion of the measuring head in a state where the measuring head is inserted, and The supported portion is provided on an outer circumferential portion of the second tubular portion in such a manner that the head holder is supported by the base casing in a predetermined posture.

9. The fixing device according to claim 1 or 2, wherein the head holder, the base housing, the first adjustment screw, the second adjustment screw, and the switching portion include a common metal material.

10. The fixing device according to claim 1 or 2, wherein The measuring head is a displacement sensor, and the displacement sensor acquires the distance from the measuring head to the measuring object arranged on the optical axis as the physical quantity, By arranging a pair of measuring heads, namely, a first measuring head and a second measuring head, to face each other on one axis across the measuring object, the thickness of the measuring object can be measured. a frame body for measuring the thickness of the measurement object, the frame body comprising a first beam portion to which the first measurement head is attached, a second beam portion to which the second measurement head is attached, and a column portion coupling the first beam portion and the second beam portion, and The fixture is used for at least one of attaching the first measuring head to the mounting surface of the first beam portion and attaching the second measuring head to the mounting surface of the second beam portion, and comprises the same material as the frame body.

11. A measuring head attached to the fixture according to claim 10 as the first measuring head or the second measuring head, the measuring head comprising an optical system holder that holds an optical system corresponding to the optical axis, The optical system and the optical system holder are configured to offset errors in the result of the thickness measurement of the measuring object caused by changes in the holding position of the measuring head held by the frame body and the fixing device during measurement of the thickness of the measuring object using the frame body, when the holding position of the measuring head held by the frame body and the fixing device on the optical axis changes with changes in the temperature environment.

12. A displacement sensor device, comprising: The first measuring head according to claim 10; The second measuring head according to claim 10; a matching degree determination unit that determines a matching degree based on an intensity of light emitted from one of the first and second measuring heads and incident on the other measuring head in a state where the first and second measuring heads are arranged to face each other, the matching degree indicating how much an optical axis of the first measuring head matches an optical axis of the second measuring head; as well as An information communication unit transmits the matching degree determination result obtained by the matching degree determination unit to a predetermined external device.

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