Optical displacement meter

Abstract

Provided is an optical displacement meter capable of obtaining cross-sectional profiles at different positions of a workpiece without providing a conveyor or a linear motion mechanism, while solving the problems of dust prevention, safety, and the like during use. An optical displacement meter (1) is provided with: a motor (20) that integrally rotates a light projection / reception module (10); a housing (40) that accommodates the light projection / reception module (10) and the motor (20); and a control unit that controls the motor (20). The housing (40) has: a first space (R1) in which the light-projecting / light-receiving module (10) is housed; and a second space (R2) for accommodating the motor (20), the second space (R2) being arranged side by side with the first space (R1) in the direction of the central axis of the light projection / reception module (10). The control unit rotates the light projection / reception module (10) by driving a motor (20) housed in the second space (R2), thereby scanning the slit light in a direction orthogonal to the X direction.

Description

Technical Field

[0001] The present disclosure relates to an optical displacement meter that measures the displacement of a workpiece using light. Background Art

[0002] As an optical displacement meter, an optical displacement meter configured as follows is known: for example, a slit light extending in the X direction is irradiated to a workpiece, and reflected light reflected by the surface of the workpiece is received, thereby obtaining an XZ cross-sectional profile. By obtaining a plurality of XZ cross-sectional profiles at different positions in the Y direction of the workpiece, data of the three-dimensional shape of the workpiece can be generated. However, in this case, a conveyor for transporting the workpiece in the Y direction, a direct-acting mechanism for moving the displacement meter body relative to the workpiece in the Y direction, and the like are required, which is sometimes difficult to introduce.

[0003] In contrast, there is known a structure in which a light-projecting system for projecting slit light and a light-receiving system for receiving reflected light (collectively referred to as a light-projecting and light-receiving system) are rotatably constructed, such as in Patent Documents 1 and 2, and the light-projecting and light-receiving system is rotated so that the slit light can scan the workpiece in the Y direction.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: European Patent Publication No. 3232152

[0007] Patent Document 2: China Utility Model Registration No. 210664364 Utility Model Content

[0008] Problems to be solved by utility models

[0009] In addition, by rotating the light projecting and receiving system as in Patent Documents 1 and 2, a plurality of cross-sectional profiles at different positions of the workpiece can be obtained without providing equipment such as a conveyor or a linear motion mechanism, which has the advantage of being easy to introduce.

[0010] However, if actual use is considered, in terms of dust prevention and dealing with interference light, it is conceivable to accommodate the light-projecting and light-receiving system in a housing. Not only is it necessary to prevent dust and deal with interference light, but if there is no housing, the rotating light-projecting and light-receiving system will be exposed, which is visually annoying. In addition, safety considerations need to be taken to prevent contact with the rotating light-projecting and light-receiving system. However, neither patent document 1 nor patent document 2 discloses a housing that can accommodate the light-projecting and light-receiving system, so it is believed that various problems such as dust prevention, dealing with interference light, visual annoyance, and safety may arise.

[0011] In addition, in the case of an optical displacement meter that uses the principle of triangulation during measurement, there is the following situation: the setting distance varies depending on the size of the workpiece, and the longer the setting distance, the larger the interval between the light-emitting unit and the light-receiving lens, and conversely, the shorter the setting distance, the smaller the interval between the light-emitting unit and the light-receiving lens. Therefore, in the case of a relatively short setting distance, it is necessary to consider the device structure in order to not make the interval between the light-emitting unit and the light-receiving lens too large.

[0012] The present disclosure is completed in view of the above-mentioned problems, and its purpose is to provide an optical displacement meter that can obtain the cross-sectional profile at different positions of the workpiece without setting up a conveyor or a direct-acting mechanism while solving problems such as dust prevention and safety during operation.

[0013] Solutions for solving problems

[0014] In order to achieve the above-mentioned purpose, in this method, an optical displacement meter that uses light to measure the displacement of a workpiece can be used as a premise. The optical displacement meter includes: a light-projecting and light-receiving module, which has a light-projecting part, a light-collecting part, and a camera part, the light-projecting part irradiates a slit light extending in the X direction, the light-collecting part has a light-receiving lens that collects the reflected light obtained by the workpiece, and the camera part receives the light collected by the light-collecting part; a motor that rotates the light-projecting and light-receiving module as a whole; a housing that accommodates the light-projecting and light-receiving module and the motor; and a control unit that controls the motor. The housing has: a first space that accommodates the light-projecting and light-receiving module; and a second space that is configured to be parallel to the first space in the direction of the rotation axis of the light-projecting and light-receiving module, the second space accommodates the motor, and the control unit can rotate the light-projecting and light-receiving module by driving the motor accommodated in the second space, so that the slit light is scanned in a direction orthogonal to the X direction.

[0015] According to this structure, when the light-emitting and light-receiving module is rotated while the housing is fixed, the slit light extending in the X direction scans the workpiece in a direction orthogonal to the X direction. As a result, there is no need for a conveyor for transporting the workpiece in the Y direction, a direct-acting mechanism for moving the displacement meter body relative to the workpiece in the Y direction, and other equipment, and it is possible to obtain multiple cross-sectional profiles at different positions of the workpiece to generate data on the three-dimensional shape of the workpiece. In addition, the light-emitting and light-receiving module rotates in a state of being accommodated in the housing, so that dust prevention and interference light can be achieved, and since the light-emitting and light-receiving module and the motor are accommodated in the housing, it is not visually annoying, and the safety of the light-emitting and light-receiving module when rotating is improved.

[0016] In addition, the light-projecting and light-receiving module is arranged side by side with the motor in the direction of the central axis thereof, so when setting the positional relationship between the light-projecting part and the light-receiving lens of the light-projecting and light-receiving module, it is not easily affected by the motor. Therefore, it is also possible to design the light-projecting part and the light-receiving lens so as not to make the distance between them larger, such as when the setting distance is relatively short.

[0017] Preferably, the rotation axis of the light projecting and light receiving module is arranged to be substantially consistent with the center of gravity of the light projecting and light receiving module on a YZ plane orthogonal to the X direction.

[0018] Preferably, the light projecting part and the light focusing part of the light projecting and light receiving module are arranged at intervals from each other in the radial direction of the rotation axis of the light projecting and light receiving module, and the light focusing part is constructed to be heavier than the light projecting part, and a counterweight is provided at a position in the light projecting and light receiving module that is closer to the light projecting part than to the light focusing part, so as to suppress the deviation of the center of gravity position of the light projecting and light receiving module from the rotation axis on the YZ plane orthogonal to the X direction due to the difference in weight of the light projecting part and the light focusing part.

[0019] Preferably, the light-projecting portion includes a light source and a light source housing for accommodating the light source, the light-focusing portion further includes a lens housing for accommodating the light-receiving lens, the light-projecting portion and the light-focusing portion of the light-projecting and light-receiving module are arranged to be spaced apart from each other in the radial direction of the rotation axis of the light-projecting and light-receiving module, and the volume of the light source housing is configured to be smaller than the volume of the lens housing, and the light source housing is composed of a material having a higher density than that of the lens housing, so as to suppress the deviation of the center of gravity position of the light-projecting and light-receiving module from the rotation axis on a YZ plane orthogonal to the X direction caused by the difference in weight between the light-projecting portion and the light-focusing portion.

[0020] Preferably, the light-projecting and light-receiving module also has a reflecting component, which is arranged on the optical path of the light concentrated by the focusing unit, and reflects the concentrated light toward the camera unit, so that the distance from the rotation axis of the light-projecting and light-receiving module to the camera unit is shortened, and the reflecting component is held integrally together with the light-projecting unit, the focusing unit and the camera unit.

[0021] Preferably, the light-projecting and light-receiving module also has a reflecting component, which is arranged on the optical path of the reflected light obtained by the workpiece, and reflects the reflected light toward the focusing part, so that the distance from the rotation axis of the light-projecting and light-receiving module to the focusing part is shortened, and the reflecting component is held integrally together with the light-projecting part, the focusing part and the camera part.

[0022] Preferably, the rotation axis of the light projecting and receiving module is arranged at a position overlapping with the light focusing unit when viewed along the rotation axis.

[0023] Preferably, the rotation axis of the light projecting and receiving module is arranged at a position overlapping with the light focusing unit when viewed along the rotation axis, or is arranged between the light projecting unit and the light focusing unit.

[0024] Preferably, there is also a bearing, which supports the rotating shaft of the light projecting and receiving module, and the moment load generated by the difference between the part of the rotating shaft supported by the bearing and the center of gravity position of the light projecting and receiving module configured to be parallel to the motor in the direction of the rotating shaft is supported by the bearing.

[0025] Preferably, an optical encoder is further provided, the optical encoder being used to detect the rotation angle of the rotation axis of the light projecting and receiving module, and the optical encoder being accommodated in the second space so as to prevent foreign matter from intruding from outside the housing and preventing foreign matter from intruding from the first space.

[0026] Preferably, assuming that the light projection and light receiving module is rotated to a first rotation angle, on a YZ plane orthogonal to the X direction, the light projection and light receiving module has a size that contacts the inner wall of the shell, and the rotation angle range of the light projection and light receiving module rotated during measurement is set to a specified angle range smaller than the first rotation angle to avoid contact between the light projection and light receiving module and the inner wall of the shell.

[0027] Preferably, the control unit controls the motor so as to avoid contact between the light projecting and light receiving module and the inner wall of the housing by rotating the light projecting and light receiving module within the predetermined angle range during measurement.

[0028] Preferably, a stopper is provided inside the housing, and the stopper is used to prevent the light projecting and receiving module from rotating to the first rotation angle outside the prescribed angle range and contacting the inner wall of the housing during measurement.

[0029] Preferably, the control unit is accommodated in a third space in the shell that is different from the first space and the second space. In the direction of the rotation axis of the light projecting and light receiving module, the third space is configured at a position different from the first space that accommodates the light projecting and light receiving module. On the other hand, the third space is configured at the same position as the second space that accommodates the motor. When observed along the rotation axis of the light projecting and light receiving module, the first space and the second space are configured at positions overlapping with the rotation axis. On the other hand, the third space is configured at a position that does not overlap with the rotation axis.

[0030] Preferably, when observed along the rotation axis of the light projecting and light receiving module, the width of the first space accommodating the light projecting and light receiving module is larger than the width of the second space accommodating the motor, and a recess into which an operator can insert his fingers to hold is formed on the outer wall of the shell due to the height difference between the first space and the second space.

[0031] Effect of utility model

[0032] As described above, by rotating the light-projecting and light-receiving module arranged parallel to the central axis of the motor while being housed in the housing, the slit light can be scanned in a direction orthogonal to the X direction. This makes it possible to obtain the contours of the workpiece at multiple positions with high precision without providing a conveyor or a direct-acting mechanism while solving problems such as dust prevention and safety during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a diagram for explaining the operation of the optical displacement meter according to the first embodiment of the present invention.

[0034] Figure 2 This is a perspective view of the optical displacement meter according to Embodiment 1 of the present invention as viewed from above.

[0035] Figure 3 This is a perspective view of the optical displacement meter according to Embodiment 1 of the present invention as viewed from below.

[0036] Figure 4 This is a plan view showing the interior of the upper space of the optical displacement meter according to the first embodiment of the present invention.

[0037] Figure 5 It is a top view of the light projecting and receiving module of the optical displacement meter according to the first embodiment of the present invention.

[0038] Figure 6 This is a block diagram showing the structure of the optical displacement meter according to the first embodiment of the present invention.

[0039] Figure 7 yes Figure 2 VII-VII line cross-sectional view.

[0040] Figure 8 yes Figure 2 Cross-sectional view along line VIII-VIII.

[0041] Fig. 9 It is a diagram for explaining the method of displacement measurement.

[0042] Fig.10is a modification example 1 of implementation example 1 and Figure 5 Quite a picture.

[0043] Fig.11 is a modification example 2 of implementation example 1 and Figure 4 Quite a picture.

[0044] Fig.12 This is a diagram showing the internal structure of the optical displacement meter according to Modification 2 of Embodiment 1 as viewed from below.

[0045] Fig.13 This is the same as the embodiment 2. Figure 2 Quite a picture.

[0046] Fig.14 This is a diagram showing the internal structure of the optical displacement meter according to the second embodiment as viewed from above.

[0047] Fig.15 This is the same as the embodiment 2. Figure 7 Quite a picture.

[0048] Fig.16 A variation of implementation example 2 involves Fig.14 Quite a picture. DETAILED DESCRIPTION

[0049] Hereinafter, embodiments of the present invention will be described in detail based on the accompanying drawings. In addition, the following description of the preferred embodiments is essentially illustrative and is not intended to limit the present invention, its application or its use.

[0050] (Implementation Method 1)

[0051] Figure 1 This is a diagram for explaining the operation of the optical displacement meter 1 according to the first embodiment of the present invention. The optical displacement meter 1 is an example of a light-section type optical displacement meter that measures the cross-sectional profile of a workpiece W (measurement object) having a height in the Z direction based on the principle of triangulation using slit light S1. In this embodiment, an example of an inspection system S composed of the optical displacement meter 1, the controller 2, and the personal computer PC is described, but the present invention is not limited to this structural example, and for example, the inspection system S may include a PLC (programmable logic controller) or the like.

[0052] When setting the inspection system S before operation, various inspection settings can be performed by, for example, the controller 2 and the personal computer PC. When operating after the settings, the optical displacement meter 1 measures the displacement of the workpiece W at a predetermined timing. Data indicating the measurement results are sent from the optical displacement meter 1 to the controller 2 and the personal computer PC, and inspection based on the inspection settings is performed. Data indicating the measurement results of the optical displacement meter 1, inspection results, etc. can be stored in the controller 2 and the personal computer PC.

[0053] When operating, it is also possible to operate only with the optical displacement meter 1 without using the controller 2 and the personal computer PC. Figure 1 In the following description, the inspection system S including the optical displacement meter 1 is described, but the present invention can also be applied to the case of using only the optical displacement meter 1 or the case of using a system combining the optical displacement meter 1 and a PLC.

[0054] The inspection system S is a system that performs an appearance inspection of the workpiece W online. In the appearance inspection performed online, for example, the appearance inspection of the workpiece W is performed sequentially at a site where a plurality of workpieces W are sequentially transported. Figure 1 The X direction, Y direction, and Z direction of the workpiece W are defined as shown. The X direction and the Y direction are mutually orthogonal when the workpiece W is viewed from above. The Z direction is the height direction of the workpiece W, and is a direction orthogonal to the X direction and the Y direction. The X direction of the workpiece W can also be called the depth direction of the workpiece W, and the Y direction of the workpiece W can be called the width direction of the workpiece W, but this definition is an example, and the definition of the X direction, Y direction, and Z direction of the workpiece W is arbitrary.

[0055] The height data of the workpiece W can be obtained by the optical displacement meter 1, so the appearance inspection includes dimension inspection, shape inspection, defect inspection, etc. based on the height data. The workpiece W is not particularly limited, and various parts, components, devices, instruments, and parts thereof can be listed. The workpiece W can also be called a measurement object. After the workpiece W is transported to the measurable area of ​​the optical displacement meter 1 by a transport device (not shown), the optical displacement meter 1 performs displacement measurement.

[0056] The optical displacement meter 1 is used in a state of being fixed to, for example, a mounting member 5. The mounting member 5 is a part of equipment installed in a factory or the like, and is fixed so as not to move relative to the workpiece W. Therefore, the optical displacement meter 1 does not move relative to the workpiece W. Although the details will be described later, even if the optical displacement meter 1 is fixed to the mounting member 5, the light projecting and receiving module 10 (such as Figure 4The optical displacement meter 1 (as shown) can rotate around an axis parallel to the X direction, so that the slit light S1 extending along the X direction of the workpiece W can be scanned from the light projecting and light receiving module 10 in a direction orthogonal to the X direction of the workpiece W, and the reflected light S2 obtained by being reflected by multiple locations in the Y direction of the surface W1 of the workpiece W is received by the light projecting and light receiving module 10. In this way, when the light projecting and light receiving module 10 is rotated around an axis parallel to the X direction, the slit light S1 can be scanned on the surface W1 of the workpiece W as in the case where the workpiece W or the optical displacement meter 1 is moved linearly. In addition, the optical displacement meter 1 scans the slit light S1 by rotating the light projecting and light receiving module 10, so the scanning direction of the slit light S1 is a direction including the Y direction and orthogonal to the X direction on the YZ plane. In addition, in this specification, "rotation" refers to a reciprocating swinging motion centered on the rotation axis.

[0057] By performing signal processing based on the amount of light received by the reflected light S2, multiple cross-sectional profiles of the workpiece W at different rotation angles can be obtained. Data (height data) of the three-dimensional shape of the workpiece W can be generated based on the obtained cross-sectional profiles. In addition, since the slit light S1 rotates, the cross-sectional profile is not necessarily parallel to the XZ plane.

[0058] By making the light projecting and receiving module 10 disposed inside the optical displacement meter 1 rotatable as described above, a plurality of cross-sectional profiles of the workpiece W at different rotation angles can be obtained without conveying the workpiece W in the Y direction and without moving the optical displacement meter 1 in the Y direction relative to the workpiece W. Therefore, there is no need for a conveyor for conveying the workpiece W, a direct-acting mechanism for moving the optical displacement meter 1 in the Y direction relative to the workpiece W, and the like, and it is easy to introduce an inspection process using the optical displacement meter 1.

[0059] In addition, the workpiece W may be relatively moved relative to the optical displacement meter 1, but multiple cross-sectional profiles may be obtained with the workpiece W stopped during measurement. In addition, the optical displacement meter 1 may be relatively moved relative to the workpiece W, but multiple cross-sectional profiles may be obtained with the optical displacement meter 1 stopped during measurement. The present invention is not limited to a case where the optical displacement meter 1 is completely fixed, and may be supported on the mounting member 5 in a movable manner, or may be mounted on a robot arm and moved to any measurement location.

[0060] Figure 2 This is a perspective view of the optical displacement meter 1 according to the first embodiment of the present invention as viewed from above. Figure 3This is a stereoscopic view of the optical displacement meter 1 according to Embodiment 1 of the present invention as viewed from below. The left-right direction, depth direction, and up-down direction of the optical displacement meter 1 are defined as shown in the respective figures, but this is for the sake of convenience of explanation and does not limit the posture of the optical displacement meter 1 during operation. Figure 1 In the illustrated application mode, the optical displacement meter 1 is disposed above the workpiece W, so that the slit light S1 is irradiated downward and the reflected light S2 is directed upward. In the case of this application mode, the left-right direction of the optical displacement meter 1 corresponds to the Y direction of the workpiece W, the up-down direction of the optical displacement meter 1 corresponds to the X direction of the workpiece W, and the depth direction of the optical displacement meter 1 corresponds to the Z direction of the workpiece W. In addition, the optical displacement meter 1 may be disposed so that the slit light S1 irradiates the workpiece W from the optical displacement meter 1 in the horizontal direction, or the optical displacement meter 1 may be disposed so that the slit light S1 irradiates the workpiece W from the optical displacement meter 1 downward, and the posture of the optical displacement meter 1 when disposed is not particularly limited.

[0061] Figure 4 1 is a diagram showing the internal structure of the optical displacement meter 1. The optical displacement meter 1 includes a light projecting and receiving module 10 (in Figure 5 ), a motor 20 for rotating the light projecting and receiving module 10 (in Figure 7 ), the motor control unit 30 (in Figure 8 ), and a housing 40. The light projecting and receiving module 10, the motor 20, and the motor control unit 30 are accommodated in the housing 40. Figure 6 As shown, in the present embodiment 1, the control unit 3 is composed of a motor control unit 30, a power supply unit 34 (described later), and a signal processing unit 32 (described later). Figure 6 In the figure, for the sake of convenience of explanation, the motor control unit 30 and the signal processing unit 32 are described separately, but the motor control unit 30 and the signal processing unit 32 may be combined.

[0062] The light projecting and receiving module 10 comprises: a light projecting section 11, which irradiates a slit light S1 extending along the X direction; a light focusing section 12, which has a light receiving lens for focusing the reflected light S2 obtained by reflection from the workpiece W; a camera section 13, which receives the light focused by the light focusing section 12; and a supporting member 14, which holds the light projecting section 11, the light focusing section 12 and the camera section 13 as a whole.

[0063] like Figure 6As shown, the light projecting unit 11 includes a laser emitter (light source) 11a, an optical system 11b, a light source housing that accommodates the laser emitter 11a and the optical system 11b, and a light projecting control unit 11c that controls the laser emitter 11a. The laser emitter 11a is controlled by the light projecting control unit 11c to emit a laser of a specified light amount at a specified timing for a specified time. The light emitted from the laser emitter 11a is incident on the optical system 11b. Although not shown in the figure, the optical system 11b is composed of a plurality of lenses including a cylindrical lens, for example, so that the incident laser is expanded into a strip shape and becomes a slit light S1, which is then irradiated onto the workpiece W. The light projecting unit 11 is in a shape that is long in the irradiation direction of the slit light S1.

[0064] The light collecting unit 12 is configured as a lens unit including a plurality of large-diameter light receiving lenses to increase the amount of light received, and the light collecting unit 12 includes a light receiving lens and a lens housing for accommodating the light receiving lens. Since the light collecting unit 12 includes a plurality of such large-diameter lenses, the size is relatively large, so the weight of the light collecting unit 12 is heavier than that of the light projecting unit 11.

[0065] The imaging unit 13 includes an image sensor 13a such as a CMOS (complementary MOS) and an imaging control unit 13b. The image sensor 13a is controlled by the imaging control unit 13b to perform imaging at a predetermined timing. The exposure time of the image sensor 13a during imaging can be controlled by the imaging control unit 13b.

[0066] like Figure 7 , Figure 8 As shown in FIG. 1 , the support member 14 is composed of a flat plate-shaped high-rigidity member, such as a metal plate. Figure 7 As shown, the support member 14 is fixed to the rotating shaft 50 constituting a part of the optical displacement meter 1, and is supported by the housing 40 so as to be rotatable about the rotation center line A as the axis of the rotating shaft 50. The extending direction of the support member 14 is a direction orthogonal to the rotation center line A.

[0067] The light projecting unit 11, the light collecting unit 12, and the image pickup unit 13 are fixed to the upper surface of the supporting member 14. Figure 5 In the top view of the light projecting and receiving module 10 shown, the light projecting unit 11 is fixed to the portion of the support member 14 on the left side of the rotation center line A, and the light focusing unit 12 and the imaging unit 13 are fixed to the opposite side. Thus, the light projecting unit 11 and the light focusing unit 12 are arranged at a distance from each other in the radial direction (Y direction, Z direction) of the rotation axis 50.

[0068] The light projecting part 11 is configured so that the irradiation direction of the slit light S1 is toward the Z direction. The light focusing part 12 is configured on the front side (the workpiece W side) of the support member 14 in such a manner that the optical axis is along the incident direction of the reflected light S2. Therefore, the light projecting part 11 and the light focusing part 12 are both toward the Z direction, but the optical axis of the optical system 11b of the light projecting part 11 and the optical axis of the light focusing part 12 (the optical axis of the light receiving lens) are in a relationship of crossing each other at a position away from the light projecting and light receiving module 10 in the Z direction. The distance between the light projecting part 11 and the light focusing part 12 in the left-right direction, and the relationship between the optical axis of the optical system 11b of the light projecting part 11 and the optical axis of the light focusing part 12 can be changed according to the installation distance of the optical displacement meter 1 relative to the workpiece W, the measurement accuracy, etc., so the example shown in the figure is only an example.

[0069] The longer the distance between the focusing unit 12 and the rotation axis, the greater the moment of inertia of the focusing unit 12 generated by the rotation. When switching the rotation direction of the projection and light receiving module 10, it is necessary to temporarily stop the projection and light receiving module 10. At this time, the greater the moment of inertia, the greater the energy required to decelerate the rotational motion of the projection and light receiving module 10, which results in an increase in the distance and time until the rotational motion stops. Therefore, the projection and light receiving module 10 is also provided with a light receiving side reflection member 15 fixed to the supporting member 14. Thus, not only can the size of the projection and light receiving module 10 be made compact, but also the moment of inertia generated by the rotation is reduced to shorten the measurement interval. The light receiving side reflection member 15 is composed of, for example, a plane mirror, so that the reflected light S2 emitted from the focusing unit 12 is folded back to the projection unit 11 side, thereby shortening the distance between the imaging unit 13 or the focusing unit 12 and the rotation axis 50 of the projection and light receiving module 10 on the YZ plane. The folding direction may also be, for example, the direction toward the center position in the Y direction of the housing 40. The YZ plane is a plane including both a straight line extending in the Y direction and a straight line extending in the Z direction, and is a plane that is orthogonal to the X direction.

[0070] Specifically, the light-receiving side reflective member 15 is positioned at the right end of the portion of the support member 14 that is further rearward than the light-collecting unit 12, and is disposed on the optical path between the imaging unit 13 and the light-collecting unit 12 on the YZ plane, so that the light collected by the light-collecting unit 12 is reflected toward the imaging unit 13. In addition, the rotation axis 50 of the light-projecting and light-receiving module 10 is disposed between the light-receiving side reflective member 15 and the light-projecting unit 11 on the YZ plane.

[0071] The light receiving side reflector 15 can be arranged on the optical path between the imaging unit 13 and the light focusing unit 12 to reflect the light that has been focused by the light focusing unit 12. Therefore, the area of ​​the light receiving side reflector 15 can be reduced. In addition, the position of the light receiving side reflector 15 may not be on the optical path between the imaging unit 13 and the light focusing unit 12, but may be arranged on the optical path between the imaging unit 13 and the light focusing unit 12 as in the modified example 1 described later (in the optical path between the imaging unit 13 and the light focusing unit 12). Fig.10As shown in FIG. 1 , the focusing unit 12 is arranged on the optical path between the light receiving side reflecting member 15 and the imaging unit 13.

[0072] The light-receiving side reflective member 15 protrudes upward from the upper surface of the supporting member 14. In addition, the extending direction of the light-receiving side reflective member 15 is set as the depth direction. The emission direction of the reflected light S2 incident on the light-receiving side reflective member 15 can be set by the setting angle of the light-receiving side reflective member 15 so that the emission direction of the reflected light S2 is toward the light-receiving surface of the image sensor 13a.

[0073] The positional relationship between the image sensor 13a of the camera unit 13 and the optical axis of the focusing unit 12 is set to a Scheimpflug relationship in which the light receiving surface of the image sensor 13a is inclined relative to the optical axis of the focusing unit 12. An optical system that satisfies the Scheimpflug relationship can be called a Scheimpflug optical system. In the present embodiment, the light projecting unit 11, the focusing unit 12, and the camera unit 13 are integrally held on the supporting member 14 in a manner having a Scheimpflug relationship, thereby constituting a light projecting and light receiving module 10. By having a Scheimpflug relationship, the light projecting unit 11 is focused along the light projection axis, so that a focused contour image can be obtained for the reflected light obtained by the slit light being reflected by the workpiece W. Therefore, the measurement accuracy of the three-dimensional shape data of the workpiece W is improved, and a high-precision contour can be obtained.

[0074] Even when the light projecting and receiving module 10 is rotated around the rotation center line A, the relative positional relationship among the light projecting unit 11, the light focusing unit 12, the imaging unit 13 and the light receiving side reflective member 15 does not change. Therefore, regardless of the rotation angle of the light projecting and receiving module 10, the Scheimpflug relationship is maintained.

[0075] The imaging unit 13 includes a cover glass 13c. The cover glass 13c is formed to cover the light receiving surface of the image sensor 13a and is fixed to the image sensor 13a. The cover glass 13c is composed of a light-transmitting member having a property of transmitting the reflected light S2 emitted from the light-receiving side reflection member 15. The reflected light S2 that has passed through the cover glass 13c forms an image on the light receiving surface of the image sensor 13a.

[0076] The rotation axis 50 of the light projecting and light receiving module 10 is configured to be substantially consistent with the center of gravity position of the light projecting and light receiving module 10 on the YZ plane. That is, in the light projecting and light receiving module 10, the light projecting unit 11, the light focusing unit 12, the camera unit 13, and the light receiving side reflective member 15 are included in the light projecting and light receiving module 10, and when the center of gravity position of the light projecting and light receiving module 10 is measured or calculated in a state where the light projecting unit 11, the light focusing unit 12, the camera unit 13, and the light receiving side reflective member 15 are fixed to the support member 14, the center of gravity position of the light projecting and light receiving module 10 is substantially consistent with the rotation center line A. In other words, the position of the rotation axis 50 in the Y direction and the Z direction relative to the support member 14 is set in such a manner that the center of gravity position of the light projecting and light receiving module 10 becomes the rotation center. The support member 14 is fixed to the rotation axis 50 by a plurality of joint members (not shown) and the like, and the support member 14 and the rotation axis 50 do not rotate relative to each other.

[0077] By making the center of gravity position of the light-projecting and light-receiving module 10 roughly coincide with the rotation center line A, the moment of inertia of the light-projecting and light-receiving module 10 caused by rotation is reduced, and the load of the motor 20 caused by, for example, vibration is suppressed, and the decrease in the rotation speed of the light-projecting and light-receiving module 10 is also suppressed. The center of gravity position of the light-projecting and light-receiving module 10 may not be strictly consistent with the rotation center line A, as long as the deviation is within the allowable degree of manufacturing tolerance. In addition, even if the center of gravity position of the light-projecting and light-receiving module 10 deviates slightly from the rotation center line A, it can be regarded as substantially consistent. For example, as long as the moment of inertia of the light-projecting and light-receiving module 10 can be sufficiently reduced, the load of the motor 20 caused by vibration is sufficiently suppressed, and the decrease in the rotation speed of the light-projecting and light-receiving module 10 can be suppressed, so as long as this effect can be achieved, a slight deviation of the center of gravity position of the light-projecting and light-receiving module 10 from the rotation center line A is allowed, and the two can be said to be roughly consistent.

[0078] As described above, the weight increases due to the enlarged diameter of the light-collecting unit 12. Therefore, it is conceivable that the center of gravity of the light-emitting and light-receiving module 10 may be too close to the light-collecting unit 12, making it difficult to design the center of gravity close to the rotation center line A. Figure 5 As shown by the virtual line in FIG. 1 , a counterweight 16 can be provided at a position on the light-projecting unit 11 side of the light-projecting and light-receiving module 10. Thus, the center of gravity of the light-projecting and light-receiving module 10 can be positioned at the middle of the light-projecting unit 11 and the light-focusing unit 12. The counterweight 16 is arranged at a position on the opposite side of the light-focusing unit 12 across the rotation center line A. The counterweight 16 can be fixed to the supporting member 14 or to the light-projecting unit 11. The number of the counterweights 16 is not limited to one, but may be multiple.

[0079] The closer the rotation axis of the light-projecting and light-receiving module 10 is to the center of gravity, the more stable the rotation can be and the more the load on the rotation axis 50 can be suppressed. However, it is conceivable that the weight of the light-projecting unit 11 and the light-focusing unit 12 are different. With this structure, a counterweight is provided at a position in the light-projecting and light-receiving module 10 that is closer to the light-projecting unit 11 than to the light-focusing unit 12, so that the deviation between the center of gravity of the light-projecting and light-receiving module 10 and the rotation axis 50 caused by the weight difference can be suppressed, thereby stabilizing the rotation and suppressing the load on the rotation axis 50.

[0080] It is also possible not to provide the counterweight 16, but to set the material of the light source housing of the projecting part 11 to a material with a higher density than the material of the lens housing of the focusing part 12. For example, the supporting member 14 and the lens housing with a large volume can be formed of a relatively low-density material such as aluminum, and the light source housing can be formed of a relatively high-density material such as zinc and stainless steel (SUS). In this way, the projecting part 11 can be made heavy, so the center of gravity of the projecting and light-receiving module 10 can be positioned in the middle of the projecting part 11 and the light-receiving part 12. In addition, the material of the housing of the projecting part 11 can be set to a material with a higher density than the material of the housing of the light-receiving part 12, and the counterweight 16 can be provided at a position on the projecting part 11 side of the projecting part 11 in the projecting and light-receiving module 10. In addition, the volume of the light source housing is configured to be smaller than the volume of the lens housing.

[0081] like Figure 7 As shown, the housing 40 is a member for accommodating the light projecting and receiving module 10, the motor 20, and the motor control unit 30, and has a two-stage structure. That is, the housing 40 has an upper housing structure 41 constituting the upper part, and a lower housing structure 42 constituting the lower part. In addition, the two-stage structure can also be called a two-layer structure, in which case the upper housing structure 41 is the first layer, and the lower housing structure 42 is the second layer.

[0082] The upper shell structure 41 and the lower shell structure 42 may be an integral body or may be formed of different components. In this embodiment, a case where the upper shell structure 41 and the lower shell structure 42 are formed of different components is described. In this case, for example, the upper shell structure 41 and the lower shell structure 42 may be combined using a joining member (not shown) to form the shell 40.

[0083] like Figure 7 As shown, the upper housing structure 41 has an upper peripheral wall 43 and an upper wall 44. The upper wall 44 extends along the YZ plane. The upper peripheral wall 43 extends from the peripheral edge of the upper wall 44 toward the lower housing structure 42. The space formed inside the upper housing structure 41 is an upper space R1. The upper space R1 is closed by the lower housing structure 42, and the upper space R1 is sealed.

[0084] like Figure 2 and Figure 4 As shown in FIG. 1 , a light-projecting window 43a and a light-receiving window 43b are provided at the front side of the upper peripheral wall portion 43. The light-projecting window 43a and the light-receiving window 43b are composed of light-transmitting components. Figure 4 As shown, the light projection window 43a is arranged to face the surface of the light projection unit 11 that irradiates the slit light S1. The size and position of the light projection window 43a are set so that the slit light S1 can be irradiated from the light projection window 43a even if the light projection and light receiving module 10 rotates as long as the rotation angle of the light projection and light receiving module 10 is within a predetermined angle range described later.

[0085] In addition, the light receiving window 43b is arranged to face the light incident surface of the light focusing unit 12. The size and position of the light receiving window 43b are set so that the reflected light S2 can be incident on the light focusing unit 12 from the light receiving window 43b even if the light projecting and light receiving module 10 rotates, as long as the rotation angle of the light projecting and light receiving module 10 is within a predetermined angle range described later.

[0086] like Figure 7 As shown, the lower shell structure 42 has a substrate portion 45, a lower peripheral wall portion 46 extending downward from the substrate portion 45, and a cover member 47. The substrate portion 45 extends along the YZ plane and is a portion that closes the lower open portion of the upper shell structure 41. The cover member 47 is mounted on the lower end portion of the lower peripheral wall portion 46. The space formed inside the lower shell structure 42 is the lower space R2. The lower space R2 is sealed by the cover member 47. In short, the shell 40 has a structure that seals the interior. The sealed structure refers to a structure that suppresses external dust and garbage from invading the interior of the shell 40, for example, it can be called a dust-proof structure. In addition, the shell 40 may not be completely sealed, for example, there may be a gap through which air can slightly enter and exit.

[0087] like Figure 3 and Figure 7 As also shown in FIG. 1 , recesses 46a are formed on the left and right sides of the lower peripheral wall portion 46 of the lower shell structure portion 42. When observed along the rotation axis of the light projecting and light receiving module 10, the width of the upper space R1 accommodating the light projecting and light receiving module is configured to be larger than the width of the lower space R2 accommodating the motor 20, and the recess 46a is formed on the outer wall of the shell 40 by the height difference between the upper space R1 and the lower space R2. The recess 46a can be used, for example, as a portion for an operator to insert a finger to hold when setting the optical displacement meter 1. In addition, the recess 46a can be set as needed. With this structure, a gripping portion that helps to improve user convenience can be set without creating an invalid area in the shell 40.

[0088] like Figure 7As shown, the motor 20 for rotating the light projecting and light receiving module 10 integrally is accommodated in the lower space (second space) R2. The central axis of the motor 20 accommodated in the lower space R2 is consistent with the axis core of the rotating shaft 50, and the central axis is in a posture extending in the up-down direction. On the other hand, the light projecting and light receiving module 10 is accommodated in the upper space (first space) R1. The upper space R1 and the lower space R2 are arranged side by side in the direction of the rotating axis (central axis of the motor 20) of the light projecting and light receiving module 10, so the light projecting and light receiving module 10 accommodated in the upper space R1 is configured to be arranged side by side with the motor 20 accommodated in the lower space R2 in the direction of the central axis of the motor 20. In other words, it is an optical displacement meter 1 with a multi-stage structure in which the light projecting and light receiving module 10 is arranged in the upper stage and the motor 20 is arranged in the lower stage.

[0089] The light projecting and light receiving module 10 is arranged side by side with the motor 20 in the direction of the central axis of the motor 20, so when setting the positional relationship between the light projecting section 11 and the light focusing section 12 of the light projecting and light receiving module 10, it is not easily affected by the motor 20. Therefore, it is possible to design the light projecting section 11 and the light focusing section 12 so as not to be separated too far, for example, when the installation distance is relatively short.

[0090] The optical displacement meter 1 further includes a bearing 51 for rotatably supporting the rotating shaft 50 of the light projecting and light receiving module 10. As described above, the light projecting and light receiving module 10 has a large weight, so when the light projecting and light receiving module 10 is used as a bearing, the rotation shaft 50 of the light projecting and light receiving module 10 is supported. Figure 1 When the optical displacement meter 1 is used in the posture shown, a moment load is generated on the rotating shaft 50 due to the weight of the light projecting and receiving module 10. Specifically, due to the difference between the portion of the rotating shaft 50 supported by the bearing 51 and the center of gravity position of the light projecting and receiving module 10, a moment load in a direction that causes the axis to tilt relative to the horizontal plane acts on the rotating shaft 50. In particular, in the case of the above-mentioned two-stage structure, the upper shell structure 41 and the lower shell structure 42 are arranged side by side in the direction of the central axis of the motor 20 (the rotating shaft of the light projecting and receiving module 10), so the difference between the portion of the rotating shaft 50 supported by the bearing 51 and the center of gravity position of the light projecting and receiving module 10 tends to become relatively large. In contrast, the bearing 51 of the present embodiment is configured to be able to support the moment load generated by the difference between the portion of the rotating shaft 50 supported by the bearing 51 and the center of gravity position of the light projecting and receiving module 10.

[0091] As a bearing 51 capable of supporting the above-mentioned moment load, for example, a cross roller bearing as follows can be used: a plurality of rollers 51c are arranged between an annular outer ring member 51a and an inner ring member 51b so that the axes of the rollers 51c adjacent in the circumferential direction are orthogonal to each other. That is, a step portion 45a for embedding the outer ring member 51a is formed in an annular shape on the substrate portion 45 of the lower shell structure portion 42. The outer ring member 51a is fixed to the substrate portion 45 in a state of being embedded in the step portion 45a. On the other hand, an interlocking portion 50a for the inner ring member 51b to be interlocked is formed on the upper portion of the rotating shaft 50. The inner ring member 51b is fixed in a state of being interlocked in the interlocking portion 50a. In addition, the inner ring member 51b can also be fixed to the supporting member 14 of the light projection and light receiving module 10.

[0092] By using a cross roller bearing as the bearing 51, the roller 51c is in line contact with the outer ring member 51a and the inner ring member 51b, so the rigidity is greatly improved compared with the ball-type bearing. Therefore, it is possible to set a compact bearing structure that is thin in the axial direction, and can not only withstand the radial load (radial load) of the rotating shaft 50, but also the axial load (axial load), which can improve the rigidity against the above-mentioned moment load. Therefore, no matter what posture the optical displacement meter 1 is in when it is used, smooth rotation can be achieved.

[0093] The bearing 51 may also be built into the motor 20. In addition, the bearing 51 may also be a bearing other than a cross roller bearing. When a bearing other than a cross roller bearing is used, for example, two or more ball bearings are arranged at intervals from each other in the axial direction of the rotating shaft 50. Thus, a bearing structure capable of supporting the above-mentioned moment load is obtained. When two or more ball bearings are used, one ball bearing may be retained on the base plate portion 45 of the lower housing structure portion 42, and the other ball bearing may be built into the motor 20.

[0094] The optical displacement meter 1 also includes an encoder 52 for detecting the rotation angle of the rotating shaft 50, that is, the rotation angle of the light-emitting and light-receiving module 10. The encoder 52 is an optical encoder. Optical encoders have been well known, and although not shown in the figure, for example, they include a rotating plate fixed to the lower end of the rotating shaft 50 and rotating together with the rotating shaft 50, and a fixed plate fixed to the housing 40, and are configured so that light irradiated from the light-emitting body can be received by the light-receiving body after passing through slits formed at equal intervals on the rotating plate and the fixed plate, and a pulse is generated and output by converting the received light into an electrical signal.

[0095] By setting the encoder 52 as an optical encoder, the detection accuracy of the rotation angle is improved compared to the magnetic encoder, but the resistance to dust and the like is weakened. In contrast, the encoder 52 is accommodated inside the housing 40, specifically, in the sealed lower space R2 as described above, so that dust and the like are not attached to the encoder 52. For example, the space accommodating the encoder 52 is sealed, so that even if garbage and dust enter the housing 40 when adjusting the position and posture of the camera 13 in the upper space R1 accommodating the light-projecting and light-receiving module 10, the garbage and dust are prevented from entering the lower space R2 accommodating the encoder 52 from the upper space R1 accommodating the light-projecting and light-receiving module 10 and rotating the light-projecting and light-receiving module 10. Therefore, it is easy to use an optical encoder that has high accuracy but is easily affected by garbage and dust, and can perform high-precision measurements.

[0096] The motor 20 is a direct drive motor that directly drives the light projecting and receiving module 10. Direct drive refers to a driving method in which no speed reduction mechanism is inserted between the motor 20 and the driven object. In addition, as will be described later, the present invention is not limited to direct drive motors.

[0097] The motor 20 includes a stator 21 formed of a coil and a rotor 22 formed of a permanent magnet. The rotor 22 is fixed to a portion between a bearing 51 and an encoder 52 on the outer periphery of the rotating shaft 50. The stator 21 is fixed to the lower housing structure 42 and is arranged to surround the rotor 22.

[0098] The motor control unit 30 is composed of, for example, a microcomputer, ROM, RAM, etc., and operates according to a predetermined program. Specifically, the motor control unit 30 can control the current flowing in the stator 21, thereby setting the rotation speed of the motor 20 to a desired speed and the rotation angle of the motor 20 to a desired angle. The motor control unit 30 is connected to the encoder 52. The motor control unit 30 can calculate the current rotation angle of the light projection and light receiving module 10 based on the pulse signal output from the encoder 52.

[0099] When the scanning start position, scanning end position, scanning range, etc. of the slit light S1 with respect to the workpiece W are set by the inspection setting, the rotation start position, rotation end position, rotation angle, etc. of the light projecting and light receiving module 10 corresponding to the set scanning start position, scanning end position, and scanning range can be calculated. The motor control unit 30 controls the motor 20 based on the calculation result to rotate the light projecting and light receiving module 10 in a state of maintaining the Scheimpflug relationship inside the housing 40, so that the slit light S1 is scanned in a direction orthogonal to the X direction.

[0100] The light-emitting and light-receiving module 10 is accommodated in the upper space R1 of the housing 40. Therefore, depending on the rotation angle of the light-emitting and light-receiving module 10, there is a concern that a part of the light-emitting and light-receiving module 10 may contact the inner wall of the housing 40. In contrast, in the present embodiment, the rotation angle range of the light-emitting and light-receiving module 10 that rotates during the operation of the optical displacement meter 1, that is, during measurement, is set to a predetermined angle range that prevents the light-emitting and light-receiving module 10 from contacting the inner wall of the housing 40. That is, although the light-emitting and light-receiving module 10 has a size that contacts the inner wall of the housing 40 on the YZ plane orthogonal to the X direction when the light-emitting and light-receiving module 10 is assumed to rotate to the first rotation angle, the rotation angle range of the light-emitting and light-receiving module 10 that rotates during measurement is set to a predetermined angle range that is smaller than the first rotation angle to prevent the light-emitting and light-receiving module 10 from contacting the inner wall of the housing 40. With this structure, the housing 40 can be designed based on the angle range required for the rotation of the light-emitting and light-receiving module 10, so that the housing 40 can be easily miniaturized.

[0101] As a method for setting the rotation angle range of the light projecting and receiving module 10 to a predetermined angle range, there are, for example, a method of mechanical implementation and a method of software implementation. In this embodiment, as a method of mechanical implementation, a device such as a controller is provided inside the housing 40. Figure 4 As shown in the figure, a first stopper 61 and a second stopper 62 are provided as an example of a mechanical part. In this example, the first stopper 61 and the second stopper 62 are provided to protrude upward from the base plate 45. When the light projecting and light receiving module 10 rotates in the direction of arrow B around the rotation center line A, before a part of the light projecting and light receiving module 10 contacts the inner wall of the housing 40, the light projecting and light receiving module 10 contacts the first stopper 61, thereby preventing the light projecting and light receiving module 10 from further rotating in the direction of arrow B. In addition, when the light projecting and light receiving module 10 rotates in the direction of arrow C around the rotation center line A, before a part of the light projecting and light receiving module 10 contacts the inner wall of the housing 40, the light projecting and light receiving module 10 contacts the second stopper 62, thereby preventing the light projecting and light receiving module 10 from further rotating in the direction of arrow C. That is, the first stopper 61 and the second stopper 62 are provided inside the housing 40 for preventing the light projecting and light receiving module 10 from rotating out of a predetermined angle range during measurement.

[0102] The first stopper 61 and the second stopper 62 can also be made of elastic members such as rubber or thermoplastic elastomer. Alternatively, the first stopper 61 and the second stopper 62 can be made of metal, and elastic members can be provided at the portion of the support member 14 where the first stopper 61 and the second stopper 62 abut. Thus, the sound generated when the light projecting and light receiving module 10 abuts against the first stopper 61 and the second stopper 62 can be reduced.

[0103] In addition, it is preferred that the support member 14 abuts against the first stopper 61 and the second stopper 62. This is because if the light projecting unit 11, the light focusing unit 12, etc. abut against the first stopper 61 and the second stopper 62, there is a concern that the optical axis may deviate due to the impact during the abutment. In addition, the first stopper 61 and the second stopper 62 may also be provided on the upper peripheral wall portion 43. Furthermore, only one of the first stopper 61 and the second stopper 62 may also be provided.

[0104] Next, the software-based method is described. That is, by executing the contact avoidance control by the motor control unit 30, the contact between the light projecting and light receiving module 10 and the inner wall of the housing 40 can also be avoided. The motor control unit 30 controls the motor 20 based on the rotation angle obtained by calculating the pulse signal output from the encoder 52, so that the light projecting and light receiving module 10 is rotated within a specified angle range during measurement. This control is the contact avoidance control. By executing the contact avoidance control, the contact between the light projecting and light receiving module 10 and the inner wall of the housing 40 can be avoided without setting the stoppers 61 and 62. In addition, the stoppers 61 and 62 can also be set when the contact avoidance control is executed.

[0105] It is sufficient as long as the light projecting and light receiving module 10 does not contact the inner wall of the housing 40 during measurement. The light projecting and light receiving module 10 may contact the inner wall of the housing 40 during non-measurement such as maintenance or various settings, so the motor control unit 30 can be configured to perform contact avoidance control only during measurement.

[0106] like Figure 8 As shown in FIG. 1 , a substrate storage space (third space) R3 is provided in the lower housing structure portion 42. Figure 4 In the top view shown, the substrate accommodating space R3 is offset to the far rear side relative to the center of the housing 40, and is therefore positioned at a position close to the motor 20 (in Figure 7In addition, the substrate accommodating space R3 is located below the upper space R1 that accommodates the light projecting and light receiving module 10, and is therefore a different space from the upper space R1, and is also a different space from the lower space R2. In the direction of the rotation axis of the light projecting and light receiving module 10, the substrate accommodating space R3 is configured at a position different from the upper space R1, and on the other hand, is configured at the same position as the lower space R2 that accommodates the motor 20. When observed along the rotation axis of the light projecting and light receiving module 10, the upper space R1 and the lower space R2 are configured at positions overlapping the rotation axis, and on the other hand, the substrate accommodating space R3 is configured at a position not overlapping the rotation axis. For example, in a case where the size of the light projecting and light receiving module 10 is larger than the size of the motor 20, by setting it as a two-stage structure with the upper space R1 that accommodates the light projecting and light receiving module 10 as the first stage and the lower space R2 that accommodates the motor 20 and the substrate accommodating space R3 that accommodates the motor control unit 30 as the second stage, the outer shape of the housing 40 can be made more compact.

[0107] like Figure 8 As shown, the motor control board 31 on which the motor control unit 30 is mounted, the signal processing board 33 on which the signal processing unit 32 is mounted, and the power supply board 35 on which the power supply unit 34 is mounted are accommodated in the board accommodation space R3. The motor control board 31 and the signal processing board 33 are equipped with processors such as CPU (central processing unit), DSP (digital signal processor), FPGA (field programmable gate array) that function as the motor control unit 30 and the signal processing unit 32, and are equipped with storage elements such as RAM (random access memory) and ROM (read only memory) for storing programs executed by the processors (not shown). Each board 31, 33, 35 is fixed to the lower housing structure 42. The motor control unit 30 and the signal processing unit 32 are accommodated in the board accommodation space R3 different from the upper space R1, so that the light projection unit 11 that is particularly prone to heat can be thermally separated from the motor control unit 30 and the signal processing unit 32, and the operation of the motor control unit 30 and the signal processing unit 32 can be stabilized. The arrangement of the control unit 3 is not limited to the above example, and for example, the signal processing unit 32 may be accommodated in the housing 40 and the motor control unit 30 may be arranged outside the housing 40 .

[0108] The reflected light S2 is incident from the front side of the housing 40, so the motor control unit 30, the signal processing unit 32, and the power supply unit 34 accommodated in the far rear side of the housing 40 are arranged on the side opposite to the side where the reflected light S2 is incident relative to the light projection and light receiving module 10. As a result, the motor control unit 30, the signal processing unit 32, and the power supply unit 34 do not interfere with the displacement measurement. In addition, when the Z direction is used as a reference, the motor control unit 30, the signal processing unit 32, and the power supply unit 34 are arranged in a manner adjacent to the light projection and light receiving module 10 in the Z direction. In addition, the substrate storage space R3 is sealed by the cover member 47, so that dust and the like can be prevented from adhering to each substrate 31, 33, 35.

[0109] The signal processing board 33 is located at the top, the motor control board 31 is located below the signal processing board 33, and the power supply board 35 is located below the motor control board 31. The signal processing board 33 located at the top is closest to the light-projecting and light-receiving module 10, but the signal processing board 33 is located below the support member 14 of the light-projecting and light-receiving module 10. Therefore, when the light-projecting and light-receiving module 10 rotates within a predetermined angle range, it will not contact the signal processing board 33. In other words, the motor control unit 30, the signal processing unit 32, and the power supply unit 34 are all configured to avoid contact with the light-projecting and light-receiving module 10 rotating during measurement.

[0110] The power supply unit 34 is a part that supplies power to the light projection unit 11, the camera unit 13, the motor control unit 30, and the signal processing unit 32. In the present embodiment, the power supply unit 34, the motor control unit 30, and the signal processing unit 32 are mounted on different substrates, but the present invention is not limited thereto, and any two or more of them may be mounted on one substrate in an integrated manner.

[0111] The signal processing unit 32 is composed of, for example, a microcomputer, ROM, RAM, etc., operates according to a predetermined program, and is a part that generates cross-sectional profile data of the workpiece W based on the amount of light received by the imaging unit 13. Figure 4 The wirings indicated by reference numeral 70 connect the substrates 31, 33, and 35 to the light projecting unit 11 and the imaging unit 13. The wirings 70 are flexible and are configured not to affect the rotation of the light projecting and receiving module 10.

[0112] like Fig. 9 As shown in FIG. 1 , the image sensor 13a of the imaging unit 13 has a plurality of pixels arranged two-dimensionally in a U direction corresponding to the X direction and in a V direction orthogonal to the U direction. The signal processing unit 32 obtains the brightness value (amount of received light) of each pixel of the image sensor 13a and obtains an approximate curve of brightness value changes. The signal processing unit 32 calculates the peak position in the V direction of each pixel column in the obtained approximate curve and obtains the calculated peak position as the displacement of the workpiece W.

[0113] The signal processing unit 32 performs the above-mentioned peak position calculation multiple times during the rotation of the light-emitting and light-receiving module 10. The signal processing unit 32 associates the obtained peak position with the rotation angle of the light-emitting and light-receiving module 10 when the peak position is obtained, and stores it as measurement data. The rotation angle and UV coordinates of the light-emitting and light-receiving module 10 correspond to the XYZ coordinates of the workpiece, so the cross-sectional profile data of the workpiece W at the desired rotation angle can be generated based on the measurement data. In addition, by obtaining multiple cross-sectional profiles of the workpiece W at different rotation angles, the signal processing unit 32 can generate data on the three-dimensional shape of the workpiece W.

[0114] (Variation 1 of Implementation Example 1)

[0115] Fig.10 FIG. 1 shows a light-projecting and light-receiving module 10 according to a first variation of the first embodiment. The positions of the light-projecting unit 11, the light-collecting unit 12, the imaging unit 13, and the light-receiving-side reflective member 15 of the light-projecting and light-receiving module 10 according to the first variation are different from those of the above-mentioned embodiment. Specifically, the rotation axis 50 of the light-projecting and light-receiving module 10 is arranged at a position overlapping with the light-collecting unit 12 on the YZ plane. That is, as described above, although it is desired to reduce the moment of inertia generated by the rotation of the light-projecting and light-receiving module 10 as much as possible, when the configuration is as follows: Figure 5 When the counterweight 16 shown by the virtual line is provided, the weight of the light-projecting and light-receiving module 10 increases, which is sometimes not ideal. Therefore, the counterweight 16 is not provided, and as a method of reducing the moment of inertia generated by the rotation of the light-projecting and light-receiving module 10, a method of making the light-collecting part 12 with increased weight overlap with the rotation axis 50 of the light-projecting and light-receiving module 10 in the YZ plane can be adopted. Thus, at least a part of the light-collecting part 12 is arranged on the extension line of the rotation axis 50 of the light-projecting and light-receiving module 10. In addition, the rotation axis 50 does not need to completely overlap with the light-collecting part 12, as long as at least a part of the rotation axis 50 and at least a part of the light-collecting part 12 overlap with each other when viewed from the direction of the rotation center line A. Thus, the counterweight 16 is not required, or the counterweight 16 can be made light.

[0116] In addition, in Modification 1, the imaging unit 13 and the light-receiving side reflective member 15 are arranged to sandwich the light-collecting unit 12. Thus, the light-collecting unit 12 of Modification 1 is arranged on the optical path between the light-receiving side reflective member 15 and the imaging unit 13 on the YZ plane, so that the light reflected by the light-receiving side reflective member 15 is collected and incident on the imaging unit 13.

[0117] Furthermore, the light-projecting and light-receiving module 10 of variant example 1 is provided with a light-projecting side reflection member 17. That is, the light-projecting unit 11 of variant example 1 is configured so that the slit light S1 irradiated from the optical system 11b goes to the far rear side on the left. Thus, the light-projecting unit 11 can be brought closer to the rotation center line A, and the moment of inertia generated by the rotation of the light-projecting and light-receiving module 10 can be further reduced, but the workpiece W is located on the opposite side to the slit light S1 irradiated from the optical system 11b. The light-projecting side reflection member 17 is configured so that the slit light S1 emitted from the optical system 11b of the light-projecting unit 11 is reflected toward the workpiece W side to cope with the above situation. The light-projecting side reflection member 17 is fixed to the supporting member 14 or the light-projecting unit 11, and the relative positional relationship between the light-projecting side reflection member 17 and the light-projecting unit 11 does not change even if the light-projecting and light-receiving module 10 rotates.

[0118] (Variation 2 of Implementation Example 1)

[0119] Fig.11 and Fig.12 An optical displacement meter 1 according to a second modification of the first embodiment is shown. Fig.11 This is a diagram showing the internal structure of the optical displacement meter 1 as viewed from above. Fig.12 This is a diagram showing the internal structure of the optical displacement meter 1 as viewed from the bottom.

[0120] In the optical displacement meter 1 of the second modification, the motor 20 is not a direct drive motor, but is a structure that rotates the light projecting and receiving module 10 via the speed reduction mechanism 25. Fig.11 As shown, the motor 20 and the light projecting and receiving module 10 are accommodated in the upper space R1. Fig.12 As shown, the output shaft 20a of the motor 20 passes through the substrate 45 downward to reach the lower space R2. In addition, the driven shaft 10a fixed to the light projecting and receiving module 10 also passes through the substrate 45 downward to reach the lower space R2.

[0121] The speed reduction mechanism 25 is accommodated in the lower space R2, and includes a driving pulley 25a fixed to the output shaft 20a of the motor 20, a driven pulley 25b fixed to the driven shaft 10a, and a transmission belt 25c wound around the driving pulley 25a and the driven pulley 25b. The driving pulley 25a is set to have a smaller diameter than the driven pulley 25b. The transmission belt 25c is a synchronous belt.

[0122] In Modification 2, when the output shaft 20a of the motor 20 accommodated in the upper space R1 rotates, the driving pulley 25a rotates, and the rotational force of the driving pulley 25a is transmitted to the driven pulley 25b via the transmission belt 25c. The driving force transmitted to the driven pulley 25b is transmitted to the driven shaft 10a, so that the light projecting and light receiving module 10 can be rotated by the motor 20. In the case of Modification 2, the driven shaft 10a is the rotation axis of the light projecting and light receiving module 10.

[0123] In addition, the speed reduction mechanism 25 is not limited to the combination of the pulleys 25a, 25b and the transmission belt 25c, and can also be composed of a combination of a driving sprocket, a driven sprocket and a synchronous chain, or a combination of multiple gears. Regarding the type of the motor 20, for example, a DC motor, a stepping motor, a servo motor, etc. can be used.

[0124] (Implementation Method 2)

[0125] Figure 13 to Figure 15 1 is a diagram showing an optical displacement meter 1 according to Embodiment 2 of the present invention. In Embodiment 2, the structure of the housing 400, the positional relationship between the motor 20 and the light-emitting and light-receiving module 100, etc. are different from those in Embodiment 1. Hereinafter, the same reference numerals are given to the same parts as in Embodiment 1 and the description thereof is omitted, and the different parts are described in detail.

[0126] like Fig.13 and Fig.15 As shown, the housing 400 is a one-stage structure, and the substrates 31, 33, 35 are also accommodated in the housing 400. The housing 400 can also be divided so that the space accommodating the substrates 31, 33, 35 and the space accommodating the light projecting and receiving module 100 are different spaces.

[0127] The housing 400 includes a lower wall 401, a peripheral wall 402 extending upward from the peripheral edge of the lower wall 401, and an upper cover member 403 for closing the upper open portion. A light projection window 402a through which the slit light S1 irradiated from the light projection unit 11 passes, and a light receiving window 402b through which the reflected light S2 reflected from the workpiece W passes are provided at the front side of the peripheral wall 402.

[0128] like Fig.15 As shown, an annular wall portion 404 is formed at the central portion of the lower wall portion 401, which protrudes toward the inside of the housing 400 and extends around the rotation center line A. An end wall portion 405 is formed at the front end portion of the annular wall portion 404, which extends radially along the rotation center line A. An opening portion 405a for inserting the rotating shaft 50 is formed at the central portion of the end wall portion 405.

[0129] A motor accommodation space R4 is formed inside the annular wall portion 404. The stator 21 and the rotor 22 of the motor 20 are accommodated in the motor accommodation space R4. The stator 21 of the motor 20 is fixed to the inner surface of the annular wall portion 404. That is, in the present embodiment, the stator holding portion is constituted by the annular wall portion 404 and the end wall portion 405. On the other hand, the rotor 22 of the motor 20 is fixed to the rotating shaft 50.

[0130] The outer ring member 51a of the bearing 51 is fixed to the end wall portion 405 in a state of being fitted into the step portion 405b formed in the end wall portion 405. Thus, the bearing 51 is held by the stator holding portion constituted by the annular wall portion 404 and the end wall portion 405. On the other hand, the inner ring member 51b is fitted into the fitting portion 50a formed on the rotating shaft 50.

[0131] The motor accommodation space R4 also accommodates the encoder 52. A lower cover member 406 is provided at the lower end of the housing 400. The motor accommodation space R4 is sealed by the lower cover member 406, so that dust and the like do not adhere to the encoder 52.

[0132] Similar to the first embodiment, the light projecting and receiving module 100 includes a light projecting unit 11, a light focusing unit 12, an imaging unit 13, a weight 16, etc. However, a supporting member 110 that integrally holds the light projecting unit 11, the light focusing unit 12, and the imaging unit 13 is greatly different from the supporting member 14 of the first embodiment.

[0133] That is, in Embodiment 1, the light projecting and light receiving module 10 and the motor 20 (bearing 51 and encoder 52) are arranged side by side in the direction of the rotating shaft 50 (height direction), whereas in Embodiment 2, a portion of the height range in the direction of the rotating shaft 50 of the light projecting and light receiving module 100 includes at least one of the motor 20, the bearing 51 supporting the rotating shaft 50, and the encoder 52 connected to the motor 20. Thus, when setting the positional relationship between the light projecting unit 11 and the light focusing unit 12 of the light projecting and light receiving module 100, a design can be made that takes into account the large spacing between the light projecting unit 11 and the light focusing unit 12, such as when the installation distance is relatively long.

[0134] Specifically, the support member 110 includes a fixing portion 111 fixed to the rotating shaft 50, a one side longitudinal plate portion 112 and a second side longitudinal plate portion 113, a light focusing portion holding portion 114, and a light projecting portion holding portion 115. The fixing portion 111, the one side longitudinal plate portion 112, the second side longitudinal plate portion 113, the light focusing portion holding portion 114, and the light projecting portion holding portion 115 may be integrally formed or may be formed by combining different components.

[0135] The fixing portion 111 is in the shape of a plate extending in the radial direction of the rotating shaft 50. Fig.14As shown in the circular shape, Fig.15 As shown in FIG. 1 , the end wall portion 405 is arranged to cover the end wall portion 405 from above. Fig.15 The right side, that is, one side of the fixing portion 111 in the radial direction of the rotating shaft 50, extends downward along the direction of the rotating shaft 50. The other side longitudinal plate portion 113 extends from Fig.15 The left side of the fixing portion 111, that is, the other side in the radial direction of the rotating shaft 50, extends downward along the direction of the rotating shaft 50. The one side longitudinal plate portion 112 and the other side longitudinal plate portion 113 are configured to face the annular wall portion 404. In addition, the one side longitudinal plate portion 112 and the other side longitudinal plate portion 113 are curved into an arc shape in the same manner as the annular wall portion 404. When the light projecting and receiving module 100 rotates, the one side longitudinal plate portion 112 and the other side longitudinal plate portion 113 rotate in a state of maintaining a certain gap with the annular wall portion 404.

[0136] In addition, the one side longitudinal plate portion 112 and the other side longitudinal plate portion 113 may be formed integrally. For example, an annular peripheral wall portion (not shown) extending downward from the peripheral edge of the fixing portion 111 may be formed, and the one side longitudinal plate portion 112 and the other side longitudinal plate portion 113 may be formed with a circumferential portion of the peripheral wall portion.

[0137] The light focusing unit holder 114 is in the shape of a plate extending from the lower end of the one side longitudinal plate portion 112 in the radial direction of the rotation axis 50. The light focusing unit 12, the imaging unit 13, the cover glass 13c, etc. are held on the upper surface of the light focusing unit holder 114. Therefore, the rotation axis 50 of the light projecting and receiving module 100 is arranged at a position that does not overlap with the light focusing unit 12 and the imaging unit 13 on the YZ plane.

[0138] The light projecting unit holder 115 is in the shape of a plate extending from the lower end of the other side longitudinal plate portion 113 in the radial direction of the rotation axis 50. The light projecting unit 11, the counterweight 16, etc. are held on the upper surface of the light projecting unit holder 115. Therefore, the rotation axis 50 of the light projecting and receiving module 100 is arranged at a position that does not overlap with the light projecting unit 11 on the YZ plane.

[0139] Thus, the light focusing unit holder 114 and the light projecting unit holder 115 are arranged to sandwich the rotation axis 50 and to protrude in opposite directions to each other in the radial direction of the rotation axis 50. The counterweight 16 can be fixed to the light projecting unit holder 115. Alternatively, the counterweight 16 can be fixed to a position on the side of the fixing unit 111 opposite to the side on which the one side longitudinal plate portion 112 is formed.

[0140] The support member 110 including the fixing portion 111, the one side vertical plate portion 112, the other side vertical plate portion 113, the focusing portion holding portion 114, and the projection portion holding portion 115 has a plurality of curved portions 110A in the cross section in the X direction. Since the support member 110 has a plurality of curved portions 110A in this way, the rigidity can be improved compared to the case where the support member 110 is a flat plate.

[0141] The motor 20 and the bearing 51 are arranged between the longitudinal plate portion 112 on one side and the longitudinal plate portion 113 on the other side of the support member 110. Moreover, the bearing 51 is arranged at a position between the longitudinal plate portion 112 on one side and the longitudinal plate portion 113 on the other side, where the distance from the fixing portion 111 is closer than the distance from the motor 20. Thus, the motor 20 and the bearing 51 are included in a portion of the height range of the light projecting and light receiving module 100. In addition, although not shown in the figure, only the motor 20 may be included in the height range of the light projecting and light receiving module 100, or only the bearing 51 may be included in the height range of the light projecting and light receiving module 100.

[0142] The rotation drive unit is composed of at least the motor 20, the bearing 51, and the encoder 52. In addition, the motor 20 is fixed to a wall surface (the lower wall portion 401 and the annular wall portion 404) adjacent to a light-projecting and light-receiving surface provided with a light-projecting window 402a for passing slit light and a light-receiving window 402b for passing reflected light (also collectively referred to as light-projecting and light-receiving windows).

[0143] The light-projecting and light-receiving window of this embodiment is composed of a light-projecting window 402a and a light-receiving window 402b which is independent of the light-projecting window 402a. However, the light-projecting window and the light-receiving window may be formed integrally. Figure 4 , Fig.14 In that case, it is a surface formed by a plurality of planes formed by the windows. In the case where the light-projecting and light-receiving windows are formed integrally, the light-projecting and light-receiving surface may be a surface formed by a single plane formed by the light-projecting and light-receiving windows.

[0144] The supporting member 110 supports the light projecting and light receiving module 100 in a manner such that the light projecting and light receiving module 100 is located in a plane orthogonal to the X direction and in which the rotating drive unit exists. The supporting member 110 has a first portion (e.g., a fixing portion 111) and a second portion (e.g., a focusing portion holding portion 114 and a light projecting portion holding portion 115) formed by a plurality of curved portions 110A, which have different heights in the direction of the rotation axis, and the rotating drive unit and the light projecting and light receiving module 100 exist between the plane formed by the first portion and the plane formed by the second portion on at least a portion of the cross section including the rotation axis. With this structure, the rigidity of the supporting member 110 can be improved, and the thickness of the housing 400 in the X direction can be reduced.

[0145] In addition, although not shown, the encoder 52 may also be included in the height range of the light-emitting and light-receiving module 100. For example, the encoder 52 may be disposed at the middle portion or the upper end portion of the rotating shaft 50, so that the encoder 52 is included in the height range of the light-emitting and light-receiving module 100. Alternatively, only the encoder 52 may be included in the height range of the light-emitting and light-receiving module 100, or only the motor 20 and the encoder 52 may be included in the height range of the light-emitting and light-receiving module 100, or only the bearing 51 and the encoder 52 may be included in the height range of the light-emitting and light-receiving module 100.

[0146] The light-receiving side reflective member 15 is arranged on the optical path between the light-collecting section 12 and the light-receiving window 402b of the housing 400 on the YZ plane, and reflects the reflected light S2 that has passed through the light-receiving window 402b toward the light-collecting section 12. That is, the light-collecting section 12 is arranged on the optical path between the light-collecting side reflective member 15 and the imaging section 13 on the YZ plane, and the reflected light S2 reflected by the light-receiving side reflective member 15 is concentrated and incident on the imaging section 13. Thus, the reflected light S2 can be folded back toward the light-projecting section 11 side, so that the distance between the imaging section 13 or the light-collecting section 12 and the rotation axis 50 of the light-projecting and light-receiving module 100 on the YZ plane becomes shorter.

[0147] (Variation of Implementation Example 2)

[0148] Fig.16 1 is a diagram showing an optical displacement meter 1 according to a modification of Embodiment 2. This modification omits the light-receiving-side reflective member 15. The light-collecting unit 12 is arranged so that the optical axis of the light-collecting unit 12 faces the light-receiving window 402b of the housing 400, thereby eliminating the need for the reflective member 15.

[0149] This modification is an example of a layout in which a wide interval is ensured between the light projecting unit 11 and the light collecting unit 12. For example, this modification can be applied when the installation distance is relatively long.

[0150] The above-mentioned embodiments are merely illustrative in all aspects and are not intended to be interpreted in a restrictive manner. Furthermore, all modifications and variations that fall within the equivalent scope of the claims are modifications and variations within the scope of the present invention. For example, in embodiment 2, a light-projecting side reflective component may also be provided. In addition, in embodiment 2, a speed reduction mechanism may also be provided. In addition, in embodiments 1 and 2, the motor 20 may also be provided outside the housing 40, 400.

[0151] Industrial Applicability

[0152] As described above, the optical displacement meter according to the present disclosure can be used, for example, when acquiring data on the three-dimensional shape of a workpiece.

[0153] Description of Reference Numerals

[0154] 1: optical displacement meter; 10, 100: light projecting and light receiving module; 11: light projecting unit; 12: light receiving lens; 13: camera unit; 15: light receiving side reflecting component; 16: counterweight; 19: light projecting side reflecting component; 20: motor; 30: motor control unit; 32: signal processing unit; 40, 400: housing; 51: bearing; 52: encoder; 61, 62: stopper; W: workpiece.

Claims

1. An optical displacement meter, characterized in that: have: A light projecting and receiving module, comprising a light projecting part, a light focusing part and a camera part, wherein the light projecting part irradiates slit light extending in the X direction, the light focusing part has a light receiving lens for focusing reflected light obtained by the workpiece, and the camera part receives the light focused by the light focusing part; A motor, which rotates the light-projecting and light-receiving modules integrally; a housing that accommodates the light projecting and receiving module and the motor; and a control unit for controlling the motor, The housing has: a first space for accommodating the light-projecting and light-receiving module; and a second space, which is arranged to be parallel to the first space in the direction of the rotation axis of the light projecting and receiving module, wherein the second space accommodates the motor, The control unit drives the motor accommodated in the second space to rotate the light projecting and receiving module, thereby causing the slit light to scan in a direction perpendicular to the X direction.

2. The optical displacement meter according to claim 1, characterized in that: The rotation axis of the light projecting and light receiving module is arranged so as to substantially coincide with the center of gravity of the light projecting and light receiving module on a YZ plane orthogonal to the X direction.

3. The optical displacement meter according to claim 1, characterized in that: The light projecting part and the light focusing part of the light projecting and light receiving module are arranged at a distance from each other in the radial direction of the rotation axis of the light projecting and light receiving module, and the light focusing part is configured to be heavier than the light projecting part. A counterweight is provided at a position in the light-projecting and light-receiving module that is closer to the light-projecting part than to the light-focusing part, so as to suppress the deviation of the center of gravity position of the light-projecting and light-receiving module from the rotation axis due to the difference in weight between the light-projecting part and the light-focusing part on the YZ plane orthogonal to the X direction.

4. The optical displacement meter according to claim 1, characterized in that: The light projecting unit includes a light source and a light source housing for accommodating the light source. The light focusing unit further comprises a lens housing for accommodating the light receiving lens. The light projecting part and the light focusing part of the light projecting and light receiving module are arranged at a distance from each other in the radial direction of the rotation axis of the light projecting and light receiving module, and the volume of the light source housing is configured to be smaller than the volume of the lens housing. The light source housing is made of a material having a higher density than that of the lens housing, so as to suppress the deviation of the center of gravity of the light projecting and receiving module from the rotation axis due to the weight difference between the light projecting unit and the light focusing unit in the YZ plane orthogonal to the X direction.

5. The optical displacement meter according to claim 1, characterized in that: The light-projecting and light-receiving module further includes a reflecting member, which is arranged on the optical path of the light collected by the focusing unit and reflects the collected light toward the imaging unit, so that the distance from the rotation axis of the light-projecting and light-receiving module to the imaging unit becomes shorter. The reflecting member is integrally held together with the light projecting unit, the light focusing unit, and the imaging unit.

6. The optical displacement meter according to claim 1, characterized in that: The light-projecting and light-receiving module further comprises a reflecting member, which is arranged on the optical path of the reflected light obtained by the workpiece, and reflects the reflected light toward the focusing unit, so that the distance from the rotation axis of the light-projecting and light-receiving module to the focusing unit becomes shorter. The reflecting member is integrally held together with the light projecting unit, the light focusing unit, and the imaging unit.

7. The optical displacement meter according to claim 5 or 6, characterized in that: The rotation axis of the light projecting and receiving module is arranged at a position overlapping with the light focusing unit when viewed along the rotation axis.

8. The optical displacement meter according to claim 1, characterized in that: The rotation axis of the light projecting and receiving module is arranged at a position overlapping with the light focusing unit when viewed along the rotation axis, or is arranged between the light projecting unit and the light focusing unit.

9. The optical displacement meter according to claim 1, characterized in that: A bearing is also provided, the bearing supporting the rotating shaft of the light projecting and receiving module, The bearing supports a moment load generated by a difference in position between a portion of the rotating shaft supported by the bearing and a center of gravity of the light projecting and receiving module arranged side by side with the motor in the rotating shaft direction.

10. The optical displacement meter according to claim 1, characterized in that: It also includes an optical encoder for detecting the rotation angle of the rotation axis of the light projecting and receiving module. The optical encoder is accommodated in the second space so as to prevent foreign matter from entering from outside the housing and to prevent foreign matter from entering from the first space.

11. The optical displacement meter according to claim 1, characterized in that: When the light projecting and light receiving module is assumed to rotate to a first rotation angle, the light projecting and light receiving module has a size that contacts the inner wall of the housing on a YZ plane orthogonal to the X direction. The rotation angle range of the projecting and receiving light module that rotates during measurement is set to a predetermined angle range that is smaller than the first rotation angle so as to avoid contact between the projecting and receiving light module and the inner wall of the housing.

12. The optical displacement meter according to claim 11, characterized in that: The control unit controls the motor so as to avoid contact between the light projecting and light receiving module and the inner wall of the housing by rotating the light projecting and light receiving module within the predetermined angle range during measurement.

13. The optical displacement meter according to claim 11, characterized in that: A stopper is provided inside the housing, and the stopper is used to prevent the light projecting and receiving module from rotating to the first rotation angle outside the predetermined angle range and contacting the inner wall of the housing during measurement.

14. The optical displacement meter according to claim 1, characterized in that: The control unit is accommodated in a third space in the housing that is different from the first space and the second space. In the direction of the rotation axis of the light projecting and light receiving module, the third space is arranged at a position different from the first space accommodating the light projecting and light receiving module, and on the other hand, the third space is arranged at the same position as the second space accommodating the motor. When viewed along the rotation axis of the light projecting and receiving module, the first space and the second space are arranged at positions overlapping the rotation axis, while the third space is arranged at a position not overlapping the rotation axis.

15. The optical displacement meter according to claim 1, characterized in that: When viewed along the rotation axis of the light projecting and light receiving module, the width of the first space for accommodating the light projecting and light receiving module is configured to be larger than the width of the second space for accommodating the motor. A recessed portion into which an operator can insert a finger for gripping is formed on the outer wall of the housing due to the height difference between the first space and the second space.

Images