Three-dimensional measurement probe

Abstract

This three-dimensional measurement probe (1) is capable of measuring the shape of the surface of an object to be measured with high accuracy, and is provided with: a movable body (10) having a stylus (11) the tip of which is in contact with the surface of the object to be measured; a holding mechanism (20) that holds the movable body (10) so that the movable body (10) can move in the axial direction; a housing (30) that houses the movable body (10) and the holding mechanism (20); and a vibration damping mechanism (40) for damping the vibration of the movable body (10), the vibration damping mechanism (40) having a pin (41) that moves in an axial direction in conjunction with the movement of the movable body (10), and a gel body (42) that has a first plane (42a) and a second plane (42b) that face away from each other in the axial direction, the first plane (42a) and the second plane (42b) being exposed surfaces exposed to an air layer. The pin (41) is inserted into the gel body (42) in the axial direction.

Description

Technical Field

[0001] The present invention relates to a three-dimensional measurement probe. Background Art

[0002] A three-dimensional shape measuring machine capable of measuring the three-dimensional shape of the surface of an object to be measured is known. In the three-dimensional shape measuring machine, a three-dimensional measurement probe having a stylus that contacts the object to be measured is used (for example, Patent Document 1).

[0003] In a three-dimensional shape measuring machine, the tip of a stylus of a three-dimensional measurement probe is brought into contact with the surface of the object with a certain pressing force, and the stylus traces the surface shape of the object. The displacement of the stylus is detected by a sensor, thereby measuring the three-dimensional shape of the object.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 9-96518 Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, with conventional three-dimensional measurement probes, it is sometimes difficult to measure the shape of the surface of an object to be measured with high accuracy.

[0009] The present invention solves such a problem, and an object of the present invention is to provide a three-dimensional measurement probe capable of measuring the shape of the surface of an object to be measured with high accuracy.

[0010] Solutions to Solve Problems

[0011] In order to achieve the above-mentioned purpose, one scheme of the three-dimensional measurement probe of the present invention comprises: a movable body, which has a stylus whose front end contacts the surface of the object to be measured; a holding mechanism, which holds the movable body in a manner that enables the movable body to move along a one-axis direction; a shell, which accommodates the movable body and the holding mechanism; and a vibration damping mechanism, which is used to dampen the vibration of the movable body, the vibration damping mechanism having a pin that moves along the one-axis direction in conjunction with the movement of the movable body, and a gel body having a first plane and a second plane facing each other in the one-axis direction, the first plane and the second plane being exposed surfaces exposed to the air layer, and the pin is inserted into the gel body in the one-axis direction.

[0012] Effects of the Invention

[0013] According to the present invention, the shape of the surface of the object to be measured can be measured with high accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1This is a perspective view of a three-dimensional measurement probe according to an embodiment.

[0015] Figure 2 It is a cross-sectional view of the three-dimensional measurement probe according to the embodiment.

[0016] Figure 3 It is a cross-sectional view of the three-dimensional measurement probe according to the embodiment.

[0017] Figure 4 This is a cross-sectional perspective view showing an enlarged view of a main part of the three-dimensional measurement probe according to the embodiment.

[0018] Figure 5 This is a perspective view of a casing in the three-dimensional measurement probe according to the embodiment.

[0019] Figure 6 This is a diagram showing a state when a gel is formed in the three-dimensional measurement probe according to the embodiment.

[0020] Figure 7 This is a diagram for explaining the operation of the vibration damping mechanism in the three-dimensional measurement probe disclosed in Patent Document 1.

[0021] Figure 8 This is a diagram for explaining the operation of the vibration damping mechanism in the three-dimensional measurement probe according to the embodiment.

[0022] Description of Reference Numerals

[0023] 1 three-dimensional measuring probe; 10 movable body; 11 stylus; 11a front end ball; 12 sliding shaft; 20 holding mechanism; 21 bearing; 22 magnetic force generating mechanism; 22a permanent magnet; 22b first yoke; 22c second yoke; 22d magnetic pin; 30 housing; 31 first housing portion; 32 second housing portion; 31a digging portion; 40 vibration damping mechanism; 41 pin; 42 gel; 42a first plane; 42b second plane; 50 tube; 60 first retainer; 61 through hole; 70 second retainer; 80 reflector; 100 distributor. DETAILED DESCRIPTION

[0024] (Process of obtaining one embodiment of the present invention)

[0025] Before describing an embodiment of the present invention, a process of arriving at one embodiment of the present invention will be described.

[0026] A three-dimensional measuring probe for measuring the three-dimensional shape of the surface of an object to be measured is known. For example, the three-dimensional measuring probe measures the shape of the surface of an optical component such as an aspherical lens or a reflector, or measures the shape of the surface of a mold for molding a lens or the like.

[0027] When measuring the shape of the surface of the object to be measured using a three-dimensional measurement probe, the tip of the stylus of the three-dimensional measurement probe is brought into contact with the surface of the object to be measured and the stylus traces the surface shape of the object to be measured. At this time, the stylus may vibrate, making it impossible to measure the surface shape of the object to be measured with high accuracy. In particular, if the lens is soft or the mold is hard, the stylus is likely to vibrate.

[0028] Therefore, in the past, a three-dimensional measurement probe capable of suppressing the vibration of the stylus has been proposed. As such a three-dimensional measurement probe, for example, Patent Document 1 discloses a contact probe having a vibration damping mechanism that damps the vibration of the stylus. The vibration damping mechanism disclosed in Patent Document 1 has a pin fixed to the stylus and a viscous fluid filled in a groove provided in a housing (shell), and has a structure in which the pin is inserted into the viscous fluid. With this structure, when the pin moves in the vertical direction in the viscous fluid in conjunction with the vibration of the stylus in the vertical direction, the movement of the pin is restricted by the viscous fluid. As a result, the vibration of the stylus to which the pin is fixed can be damped, and thus the vibration of the stylus can be suppressed.

[0029] However, in the contact probe disclosed in Patent Document 1, when the pin inserted into the viscous fluid moves in the up-down direction, the pin may leave the viscous fluid, so that the vibration of the stylus cannot be stably attenuated. Therefore, in the contact probe disclosed in Patent Document 1, the shape of the surface of the object to be measured may not be measured with high accuracy.

[0030] Therefore, the inventors of the present invention have conducted in-depth research on such a topic and found that, as a vibration attenuation mechanism for attenuating the vibration of the stylus, by inserting a pin that moves in conjunction with the vibration of the stylus into a gel exposed on the front and back sides, the pin can be prevented from leaving the gel, thereby obtaining a scheme for the three-dimensional measurement probe of the present invention.

[0031] Specifically, one scheme of the three-dimensional measurement probe of the present invention comprises: a movable body, which has a stylus whose front end contacts the surface of the object to be measured; a holding mechanism, which holds the movable body in a manner that enables the movable body to move along a one-axis direction; a shell, which accommodates the movable body and the holding mechanism; and a vibration attenuation mechanism, which is used to attenuate the vibration of the movable body, the vibration attenuation mechanism having a pin that moves along the one-axis direction in conjunction with the movement of the movable body, and a gel body having a first plane and a second plane facing back to back in the one-axis direction, the first plane and the second plane are exposed surfaces exposed to the air layer, and the pin is inserted into the gel body in the one-axis direction.

[0032] With this structure, the vibration of the movable body can be damped by the vibration damping mechanism, thereby suppressing the vibration of the movable body. In addition, it is possible to suppress the pin from falling off from the gel body and failing to damp the vibration of the movable body, so that the vibration of the movable body can be damped stably. Therefore, the shape of the surface of the object to be measured can be measured with high accuracy.

[0033] In one aspect of the three-dimensional measurement probe of the present invention, it is preferable that the pin penetrates the gel body.

[0034] With this structure, when the pin moves in conjunction with the vibration of the movable body, it is possible to further suppress the pin from falling off the gel body, thereby enabling the shape of the surface of the object to be measured to be measured with higher accuracy.

[0035] In one aspect of the three-dimensional measurement probe of the present invention, it is preferred that the vibration damping mechanism includes two of the pins and two of the gel bodies, and the two pins and the two gel bodies are arranged to sandwich the stylus in a plan view.

[0036] With this structure, the vibration damping mechanism can be arranged with good left-right balance around the stylus, thereby efficiently damping the vibration of the movable body.

[0037] In one aspect of the three-dimensional measurement probe of the present invention, it is preferable that the holding mechanism includes a bearing for supporting the movable body, and a magnetic force generating mechanism for generating a magnetic force for floating the movable body.

[0038] With this structure, the movable body can be held by magnetic force, so the three-dimensional measurement probe can be set as a magnetic levitation type probe. Therefore, compared with the case where the movable body is held in the axial direction by a spring member or the like, the movable body can be held with a very small force. As a result, the measuring force when measuring a three-dimensional object can be reduced, so that high-precision measurement can be performed while making contact. In particular, although the use of a gas bearing as a bearing makes it possible to maintain the object completely in non-contact and thus easily generate vibration, by holding the movable body with the help of magnetic force, a small damping force can be applied, so that its vibration can be reduced.

[0039] In one aspect of the three-dimensional measurement probe of the present invention, it is preferable that the housing is made of a magnetic material.

[0040] With this configuration, even if there is an external magnetic force such as a magnet outside the housing, the magnetic flux generated by the external magnetic force is absorbed by the housing, so the shape of the surface of the object to be measured can be measured with high accuracy.

[0041] In one aspect of the three-dimensional measurement probe of the present invention, it is preferable that the bearing is a gas bearing.

[0042] With this configuration, the shaft of the movable body can be held in a non-contact manner, so that unstable damping such as static friction due to contact holding does not occur, and ideal damping can be obtained using only the viscous resistance of the gel.

[0043] In one aspect of the three-dimensional measurement probe of the present invention, it is preferable that the gel body is made of an ultraviolet curable resin.

[0044] With this configuration, a gel can be formed by applying a liquid ultraviolet curing resin to a predetermined position and curing it with ultraviolet rays.

[0045] In one aspect of the three-dimensional measurement probe of the present invention, it is preferable that the gel body is held by a holder fixed to the housing, and the housing is configured to be separable into two in the one-axis direction at the position of the holder.

[0046] With this configuration, the liquid gel can be easily injected into a predetermined position of the holder using a dispenser and solidified.

[0047] Hereinafter, the embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments described below all represent a specific example of the present invention. Therefore, the numerical values, shapes, materials, constituent elements, configuration positions of constituent elements, and connection methods shown in the following embodiments are an example and are not intended to limit the present invention. Therefore, regarding the constituent elements of the following embodiments that are not recorded in the independent technical solutions representing the highest concept of the present invention, they are described as arbitrary constituent elements.

[0048] It should be noted that each figure is a schematic diagram and is not necessarily strictly illustrated. In addition, in each figure, the same figure mark is used for substantially the same structure, and repeated descriptions are omitted or simplified. In addition, in this specification, the terms "upper" and "lower" do not necessarily refer to the upper direction (vertically above) and the lower direction (vertically below) in absolute spatial identification. In addition, in this specification and the accompanying drawings, the X-axis, Y-axis, and Z-axis represent the three axes of a three-dimensional orthogonal coordinate system. The X-axis and the Y-axis are orthogonal to each other, and are both axes orthogonal to the Z-axis. In an embodiment, the Z-axis direction is the vertical direction.

[0049] (Implementation Method)

[0050] First, use Figure 1 to Figure 5 The structure of the three-dimensional measurement probe 1 according to the embodiment will be described. Figure 1 It is a perspective view of the three-dimensional measurement probe 1 according to the embodiment. Figure 2 It is a cross-sectional view of the three-dimensional measurement probe 1 according to the embodiment. Figure 3 is to use relative to Figure 2This is a cross-sectional view of the three-dimensional measurement probe 1 according to the embodiment when the plane is cut along a plane rotated 90 degrees. Figure 4 It is a cross-sectional perspective view showing an enlarged main part of the three-dimensional measurement probe 1 according to the embodiment.

[0051] The three-dimensional measurement probe 1 is a probe for measuring the three-dimensional shape of the surface of the object to be measured. The object to be measured by the three-dimensional measurement probe 1 is an object having a three-dimensional shape, and as an example, it is a lens such as an aspherical lens or an optical component such as a reflector. It should be noted that the object to be measured by the three-dimensional measurement probe 1 is not limited to an optical component.

[0052] like Figure 1 As shown, the three-dimensional measurement probe 1 includes a movable body 10, a holding mechanism 20 for holding the movable body 10, a housing 30 for accommodating the movable body 10 and the holding mechanism 20, and a vibration damping mechanism 40 (shown in FIG. 4 ) for damping vibration of the movable body 10. Figure 3 middle).

[0053] The movable body 10 has a stylus 11 and a sliding shaft portion 12. The stylus 11 and the sliding shaft portion 12 are fixed integrally.

[0054] The stylus 11 is fixed to one end in the longitudinal direction of the slide shaft 12. The tip of the stylus 11 contacts the surface of the object to be measured by the three-dimensional measurement probe 1. Specifically, a tip ball 11a is provided at the tip of the stylus 11, and the tip ball 11a contacts the object to be measured.

[0055] like Figure 2 As shown, the sliding shaft portion 12 is a long cylindrical member. The sliding shaft portion 12 extends in the Z-axis direction. The sliding shaft portion 12 is supported by the holding mechanism 20 so as to be slidable in the Z-axis direction.

[0056] The holding mechanism 20 holds the movable body 10 so that it can move in one axis direction. In this embodiment, the one axis direction in which the movable body 10 moves is the Z axis direction, so the holding mechanism 20 holds the movable body 10 so that it can move in the Z axis direction.

[0057] The holding mechanism 20 includes a bearing 21 that slidably supports the movable body 10 , and a magnetic force generating mechanism 22 that generates a magnetic force that floats the movable body 10 .

[0058] The bearing 21 holds the movable body 10 in a manner that allows the movable body 10 to move in a single axis direction. Specifically, the bearing 21 supports the sliding shaft portion 12 of the movable body 10. That is, the sliding shaft portion 12 slides relative to the bearing 21. In this embodiment, the bearing 21 is an air bearing. Compressed air is supplied from the pipe 50 (shown in FIG. 1 ). Figure 6The sliding shaft portion 12 is thus able to slide in the Z-axis direction without causing friction with the bearing 21 by means of the film of compressed air.

[0059] The magnetic force generating mechanism 22 generates a magnetic force to float the movable body 10 in the Z-axis direction (gravity direction) and provides the movable body 10 with a weak spring constant.

[0060] The magnetic force generating mechanism 22 has a permanent magnet 22a, a first yoke 22b, a second yoke 22c and a magnetic pin 22d. The first yoke 22b is located on the upper side of the permanent magnet 22a, and the second yoke 22c is located on the lower side of the permanent magnet 22a (the contact pin 11 side). In other words, the permanent magnet 22a is clamped by the first yoke 22b and the second yoke 22c in the Z-axis direction.

[0061] The first yoke 22b, the second yoke 22c, and the magnetic pin 22d are magnetic bodies of a predetermined shape made of magnetic material. In the present embodiment, the first yoke 22b located on the upper side is a magnetic body having a through hole in the center and extending in the X-axis direction. On the other hand, the second yoke 22c located on the lower side is composed of a pair of magnetic bodies arranged in the X-axis direction. The magnetic pin 22d is a magnetic sheet extending in the X-axis direction. Figure 2 As shown, the front end portion of the magnetic pin 22d is clamped by a pair of magnetic bodies constituting the second yoke 22c in the X-axis direction. The front end portion of the magnetic pin 22d is opposed to the second yoke 22c with a gap in the X-axis direction. As an example, the first yoke 22b, the second yoke 22c and the magnetic pin 22d are made of iron.

[0062] Moreover, the permanent magnet 22a is arrange|positioned between each of the pair of magnetic bodies which comprise the 2nd yoke 22c and the 1st yoke 22b. In other words, in this embodiment, two permanent magnets 22a are provided.

[0063] The permanent magnet 22a, the first yoke 22b, and the second yoke 22c are held by the first holder 60. On the other hand, the magnetic pin 22d is held by the second holder 70. The first holder 60 and the second holder 70 are made of a metal material such as aluminum, but are not limited thereto and may be made of a resin material.

[0064] The first holder 60 is fixed to the housing 30. On the other hand, the second holder 70 is fixed to the movable body 10. Therefore, the first holder 60 does not move even if the movable body 10 moves, and the second holder 70 moves in the Z-axis direction in conjunction with the movement of the movable body 10 when the movable body 10 moves in the Z-axis direction. Therefore, even if the movable body 10 moves, the positions of the permanent magnet 22a, the first yoke 22b, and the second yoke 22c held by the first holder 60 do not change, but the magnetic pin 22d held by the second holder 70 moves in conjunction with the movement of the movable body 10 in the Z-axis direction.

[0065] The magnetic force generating mechanism 22 configured in this way forms a magnetic circuit composed of the permanent magnet 22a, the first magnetic yoke 22b, the second magnetic yoke 22c and the magnetic pin 22d. Specifically, the permanent magnet 22a, the first magnetic yoke 22b and the second magnetic yoke 22c form a magnetic circuit with the magnetic pin 22d in a non-contact manner. In this case, the magnetic flux generated from one of the two permanent magnets 22a passes through one of the two second magnetic yokes 22c, passes through the magnetic pin 22d arranged with a gap from the second magnetic yoke 22c, passes through the other of the two second magnetic yokes 22c arranged with a gap from the magnetic pin 22d, adds the magnetic flux generated from the other of the two permanent magnets 22a and passes through the first magnetic yoke 22b, and returns to the original permanent magnet 22a. Through the magnetic circuit formed in this way, the magnetic force generating mechanism 22 generates a magnetic force that hinders the movable body 10 from moving in the Z-axis direction (uniaxial direction), and generates a magnetic force that hinders its movement in the rotation direction around the Z-axis. As a result, the movable body 10 is held in a floating state.

[0066] The housing 30 is a shell that accommodates the movable body 10 and the holding mechanism 20. A portion of the movable body 10 is exposed from the lower end of the housing 30. Specifically, the housing 30 accommodates the stylus 11 of the movable body 10 and the sliding shaft portion 12 of the sliding shaft portion 12, but does not accommodate the stylus 11. In other words, the stylus 11 is exposed from the housing 30. In addition, the housing 30 accommodates the bearing 21 and the magnetic force generating mechanism 22 in the holding mechanism 20. The housing 30 also accommodates the first retaining member 60 and the second retaining member 70. In the present embodiment, the housing 30 is made of a magnetic material. As an example, the housing 30 is made of iron, which is a ferromagnetic body. The housing 30 is an outer shell member that constitutes the outer shell of the three-dimensional measurement probe.

[0067] The housing 30 is configured to be separable into two at the position of the first holder 60 in a uniaxial direction (Z-axis direction) which is the direction in which the movable body 10 moves. Specifically, the housing 30 is configured by a first housing portion 31 and a second housing portion 32. The first housing portion 31 and the second housing portion 32 are connected and fixed by screws.

[0068] The first housing portion 31 is located below the second housing portion 32 in the Z-axis direction. That is, the second housing portion 32 is located above the first housing portion 31 in the Z-axis direction. The first housing portion 31 accommodates the bearing 21 of the movable body 10. The bearing 21 is fixed to the first housing portion 31. It should be noted that the first retainer 60 is fixed to the housing 30. Specifically, the first retainer 60 is fixed to the first housing portion 31.

[0069] In addition, as described above, when the housing 30 is formed of iron as a magnetic body, the housing 30 affects the magnetic circuit formed by the magnetic force generating mechanism 22, and the restoring force of the movable body 10 that is floated by the magnetic force generated by the magnetic force generating mechanism 22 may be reduced. For example, the magnetic flux generated by the magnetic force generating mechanism 22 may be unexpectedly absorbed by the housing 30 formed of a magnetic body, so that the magnetic force generating mechanism 22 cannot form a predetermined magnetic circuit.

[0070] Therefore, in this embodiment, if Figure 5 As shown, the first case portion 31 is provided with a hollowed portion 31 a formed by hollowing a part of the first case portion 31 toward the stylus 11 side. Figure 5 3D measurement probe 1 is a perspective view of the housing 30. The cutout portion 31a is provided between the magnetic force generating mechanism 22 and the inner wall of the first housing portion 31. By providing the cutout portion 31a in this way, a gap (air layer) is provided between the magnetic force generating mechanism 22 and the inner wall of the first housing portion 31. Therefore, even if the housing 30 is formed of iron as a magnetic body, the housing 30 can be prevented from affecting the magnetic circuit formed by the magnetic force generating mechanism 22. That is, the cutout portion 31a functions as a magnetic resistance, so that the magnetic flux generated by the magnetic force generating mechanism 22 can be prevented from being absorbed by the housing 30.

[0071] The vibration damping mechanism 40 has a function of damping the vibration of the movable body 10. Figure 3 as well as Figure 4 As shown, the vibration damping mechanism 40 has a pin 41 and a gel body 42 .

[0072] The pin 41 is fixed to the movable body 10. Therefore, the pin 41 moves in conjunction with the movement of the movable body 10 along a one-axis direction which is the direction in which the movable body 10 moves. Specifically, when the movable body 10 moves along the Z-axis direction, the pin 41 also moves along the Z-axis direction. In the present embodiment, the pin 41 is fixed to a second retaining member 70 fixed to the movable body 10. In other words, the pin 41 is not directly fixed to the movable body 10, but is fixed to the movable body 10 via the second retaining member 70. It should be noted that the pin 41 may also be directly fixed to the movable body 10. The pin 41 is preferably made of a non-magnetic material such as stainless steel. The pin 41 is a cylindrical and elongated rod-shaped member.

[0073] The gel body 42 is held by the first holding member 60. Specifically, the gel body 42 is fixed to the first holding member 60 by being embedded in the through hole 61 provided in the first holding member 60. The through hole 613 of the first holding member 60 is circular in a plan view. Therefore, the outer shape of the gel body 42 embedded in the through hole 61 is circular. Specifically, the gel body 42 is in the shape of a disk, and the height (thickness) of the gel body 42 is smaller than the diameter of the gel body 42. It should be noted that the first holding member 60 that holds the gel body 42 is fixed to the housing 30, so that even if the movable body 10 moves, the position of the gel body 42 does not change.

[0074] like Figure 4 As shown, the gel body 42 has a first plane 42a and a second plane 42b which are opposite to each other in a one-axis direction (Z-axis direction) which is the direction in which the movable body 10 moves. Specifically, the first plane 42a is the upper surface of the gel body 42 in the Z-axis direction, and the second plane 42b is the lower surface of the gel body 42 in the Z-axis direction. In this embodiment, the first plane 42a is parallel to the second plane 42b. The first plane 42a and the second plane 42b are exposed surfaces exposed to the air layer. That is, there is a space region which is an air layer above the first plane 42a and below the second plane 42b, and the first plane 42a and the second plane 42b are exposed to the air layer.

[0075] The pin 41 is inserted into the gel 42 in the uniaxial direction (Z-axis direction) which is the direction in which the movable body 10 moves. Specifically, the pin 41 is pushed up from the second plane 42b (lower surface) of the gel 42 and inserted into the gel 42. The pin 41 inserted into the gel 42 is fixed to the gel 42.

[0076] In this embodiment, the pin 41 penetrates the gel 42. In this case, the upper end surface of the pin 41 is coplanar with the first plane 42a of the gel 42, and the pin 41 extends downward from the gel 42. In other words, the pin 41 protrudes downward from the second plane 42b of the gel 42.

[0077] It should be noted that the pin 41 may also protrude from the first plane 42a of the gel body 42. In other words, the pin 41 may also penetrate the gel body 42 in a manner of protruding from both sides of the gel body 42. In addition, the pin 41 may not penetrate the gel body 42. In other words, the pin 41 may also be inserted into the gel body 42 in a manner that the upper end surface of the pin 41 is present inside the gel body 42.

[0078] The vibration damping mechanism 40 has two pins 41 and two gel bodies 42. Therefore, the first holder 60 is provided with two through holes 61 for fixing the gel bodies 42. In a plan view, the two pins 41 and the two gel bodies 42 are arranged so as to sandwich the stylus 11. That is, the two pins 41 and the two gel bodies 42 are arranged at intervals of 180 degrees with the axis of the movable body 10 (sliding shaft portion 12) as the center. That is, in a cross-sectional view, the pair of vibration damping mechanisms 40 are arranged in a bilaterally symmetrical manner.

[0079] The gel body 42 is made of a resin material. In the present embodiment, the gel body 42 is made of an ultraviolet curing resin. In the present embodiment, as the gel body 42, an ultraviolet curing silicone gel (for example, "3168" manufactured by ThreeBond) is used.

[0080] When the gel 42 is placed in the through hole 61 of the first retainer 60, Figure 6 As shown, the first housing portion 31 and the second housing portion 32 are separated, and the liquid gel 42 before curing is injected into the through hole 61 of the first retaining member 60 by using the dispenser 100 while the pin 41 is passed through the through hole 61, and the gel 42 is cured by irradiating the liquid gel 42 with ultraviolet rays. In this way, the gel 42 with the pin 41 inserted can be formed in the through hole 61 of the first retaining member 60, and the gel 42 and the pin 41 can be fixed. It should be noted that Figure 6 This is a diagram showing a state when the gel 42 is formed in the three-dimensional measurement probe 1 according to the embodiment.

[0081] In addition, since the pin 41 passes through the through hole 61 when the liquid gel 42 is injected into the through hole 61, the liquid gel 42 will not drip from the through hole 61 immediately when the liquid gel 42 is injected into the through hole 61. However, if the gap between the inner surface of the through hole 61 and the pin 41 is too large, the liquid gel 42 may drip. Therefore, the hole diameter (diameter) of the through hole 61 is preferably less than 10 times the diameter of the columnar pin 41. In this embodiment, the gel 42 with a height (thickness) of 0.5 mm is formed. In this case, the hole diameter (diameter) of the through hole 61 is set to The diameter of the pin 41 is set to That is, the hole diameter of the through hole 61 is five times the diameter of the pin 41 .

[0082] The three-dimensional measurement probe 1 configured in this way is used in a three-dimensional shape measuring machine. When the shape of the surface of the object to be measured is measured using the three-dimensional shape measuring machine, the surface shape of the object to be measured is traced while the tip of the stylus 11 of the three-dimensional measurement probe 1 is brought into contact with the surface of the object to be measured by a certain pressing force, and the displacement of the stylus 11 in the Z-axis direction is detected by a displacement detection mechanism, thereby measuring the three-dimensional shape of the object to be measured. The displacement detection mechanism includes, for example, a reflector 80 fixed to the movable body 10, a light source for emitting measurement light such as laser light, and a photodetector for detecting the measurement light reflected by the reflector 80, and the displacement of the movable body 10 in the Z-axis direction is detected by the photodetector by detecting the measurement light reflected by the reflector 80.

[0083] It should be noted that, in the present embodiment, the reflector 80 is held by the second holder 70 fixed to the movable body 10. Specifically, it is arranged on the magnetic pin 22d fixed to the second holder 70. In addition, although not shown in the figure, the light source and the light detector may be provided in the three-dimensional measurement probe 1, or may be provided in the three-dimensional shape measuring machine equipped with the three-dimensional measurement probe 1.

[0084] Next, use Figure 7 as well as Figure 8 , the effects of the three-dimensional measurement probe 1 of the embodiment will be described in comparison with the three-dimensional measurement probe 1X disclosed in Patent Document 1. Figure 7 This is a diagram for explaining the operation of the vibration damping mechanism 40X in the three-dimensional measurement probe 1X disclosed in Patent Document 1. Figure 8 This is a diagram for explaining the operation of the vibration damping mechanism 40 in the three-dimensional measurement probe 1 according to the embodiment.

[0085] like Figure 7 As shown in (a), the vibration attenuation mechanism 40X in the three-dimensional measurement probe 1X disclosed in Patent Document 1 has a pin 41X fixed to the stylus, and a viscous fluid 42X filled in a groove 61X provided in a housing 60X, so that the pin 41X is inserted into the viscous fluid 42X.

[0086] With this structure, in the vibration damping mechanism 40X disclosed in Patent Document 1, when the stylus vibrates in the vertical direction, Figure 7 As shown in (b), the pin 41X vibrates in the vertical direction in the viscous fluid 42X in conjunction with the vertical vibration of the stylus. At this time, since the movement of the pin 41X is restricted by the viscous fluid 42X, the vibration of the stylus to which the pin 41X is fixed is attenuated, thereby suppressing the vibration of the stylus.

[0087] However, in the vibration damping mechanism 40X disclosed in Patent Document 1, Figure 7As shown in (c), when the vibration of the stylus increases, when the pin 41X inserted into the viscous fluid 42X moves upward, the pin 41X may leave the viscous fluid 42X. In other words, the pin 41X may fall off from the viscous fluid 42X. Therefore, in the vibration damping mechanism 40X disclosed in Patent Document 1, the vibration of the stylus cannot be stably damped. In particular, although it is desirable to make the depth of the pin 41X inserted into the viscous fluid 42X as shallow as possible, if the depth of the pin 41X is too shallow, when the stylus vibrates, the pin 41X may fall off from the viscous fluid 42X when it moves upward.

[0088] In contrast, if Figure 8 As shown in (a) of FIG. 1 , in the vibration damping mechanism 40 of the three-dimensional measurement probe 1 of the present embodiment, a pin 41 configured to move in conjunction with the movement of the movable body 10 is inserted into a gel body 42 exposed on both the first plane 42a and the second plane 42b.

[0089] With this structure, when the pin 41 vibrates in conjunction with the vibration of the movable body 10 (stylus 11) of the three-dimensional measurement probe 1, since the pin 41 is inserted into the gel 42, the movement of the pin 41 is restricted by the gel 42. Thus, the vibration of the movable body 10 (stylus 11) can be attenuated, and thus the vibration of the movable body 10 (stylus 11) can be suppressed.

[0090] For example, when the object to be measured by the three-dimensional measurement probe 1 is a relatively soft lens, high-frequency vibrations are generated in the movable body 10 due to the spring component of the movable body 10. However, by attenuating the movable body 10 using the vibration attenuation mechanism 40 using the gel 42 as in the three-dimensional measurement probe 1 of the present embodiment, the high-frequency vibrations can be effectively suppressed.

[0091] However, if the damping force (damping effect) of the vibration damping mechanism 40 is too large, the movable body 10 may vibrate in the low frequency region. Therefore, it is advisable to set the damping force of the vibration damping mechanism 40 within an appropriate range. In this case, the damping force of the vibration damping mechanism 40 is 1×10 -4 Here, if the damping force by the vibration damping mechanism 40 is Fs, the damping force Fs is simply expressed by the following (Formula 1), and the damping force Fs is preferably within a range of 0.2 to 2 times the prescribed value.

[0092]

Mathematical formula 1

[0093]

[0094] It should be noted that, in (Formula 1), D1 is the hole diameter (diameter) of the through hole 61 for the gel 42, D2 is the diameter of the cylindrical pin 41, H is the height (thickness) of the gel 42, V is the moving speed of the pin 41, and μ represents the viscosity coefficient of the gel 42. As an example, as described above, H=0.5mm.

[0095] In addition, in the vibration damping mechanism 40 of the three-dimensional measurement probe 1 of the present embodiment, the pin 41 is linked to the vibration of the movable body 10 (stylus 11) as shown in FIG. Figure 8 When the gel body 42 is moved upward as shown in (b), the gel body 42 is pulled upward by the pin 41. In addition, the pin 41 is linked to the vibration of the movable body 10 (the stylus 11) as shown in FIG. Figure 8 When the pin 41 moves downward as shown in (c), the gel 42 is pulled downward by the pin 41. In this way, the gel 42 is pulled by the pin 41 regardless of whether the pin 41 moves upward or downward, so the pin 41 is not easily separated from the gel 42. In this case, even if the contact width between the gel 42 and the pin 41 is small, the gel 42 and the pin 41 are not easily separated when the pin 41 moves up and down.

[0096] Thus, according to the three-dimensional measurement probe 1 of this embodiment, the pin 41 can be prevented from falling off from the gel 42 and failing to damp the vibration of the movable body 10, so that the vibration of the movable body 10 can be damped stably. Therefore, the shape of the surface of the object to be measured can be measured with high accuracy.

[0097] In addition, in the three-dimensional measurement probe 1 of the present embodiment, the pin 41 penetrates the gel body 42 .

[0098] With this configuration, when the pin 41 moves in conjunction with the vibration of the movable body 10, it is possible to further suppress the pin 41 from falling off the gel body 42. Therefore, the shape of the surface of the object to be measured can be measured with higher accuracy.

[0099] In the three-dimensional measurement probe 1 of the present embodiment, the vibration damping mechanism 40 includes two pins 41 and two gel bodies 42 , and the two pins 41 and the two gel bodies 42 are arranged so as to sandwich the stylus 11 in a plan view.

[0100] With this configuration, the vibration damping mechanism 40 can be arranged with good left-right balance around the stylus 11. This makes it possible to efficiently damp the vibration of the movable body 10 (stylus 11).

[0101] In the three-dimensional measurement probe 1 of this embodiment, the holding mechanism 20 holding the movable body 10 includes a bearing 21 supporting the movable body 10 and a magnetic force generating mechanism 22 generating a magnetic force for floating the movable body 10. That is, the three-dimensional measurement probe 1 of this embodiment is a magnetic levitation type probe.

[0102] With this structure, the movable body 10 can be held with a very small force, compared with the case where the movable body 10 is elastically held by a spring member such as a suspension spring, so that the measuring force when measuring a three-dimensional object can be reduced, so that high-precision measurement can be performed while in contact. In particular, although the movable body 10 is held completely in a non-contact manner due to the use of a gas bearing such as an air bearing as the bearing 21, which easily generates vibration, a small damping force can be applied by holding the movable body 10 with the help of a magnetic force, so that its vibration can be reduced. In addition, as described above, the three-dimensional measurement probe 1 of this embodiment is a magnetic suspension gel type probe using a gel body 42 in the vibration damping mechanism 40. As a result, the vibration of the movable body 10 can be effectively suppressed.

[0103] In addition, in the three-dimensional measurement probe 1 of the present embodiment, the movable body 10 is held by the magnetic force generating mechanism 22 that forms a magnetic circuit. Therefore, when there is an external magnetic force such as a magnet outside (around) the housing 30, the external magnetic force may affect the magnetic circuit formed by the magnetic force generating mechanism 22, and the shape of the surface of the object to be measured cannot be measured with high accuracy. For example, when the housing 30 is made of aluminum, the magnetic flux generated by the external magnetic force passes through the housing 30, and the magnetic circuit formed by the magnetic force generating mechanism 22 may be affected by the external magnetic force.

[0104] Therefore, in the three-dimensional measurement probe 1 of the present embodiment, the housing 30 is made of a magnetic material.

[0105] With this structure, even if there is an external magnetic force such as a magnet outside the housing 30, the magnetic flux generated by the external magnetic force will be absorbed by the housing 30, thereby preventing it from reaching the inside of the housing 30. In other words, the housing 30 functions as a magnetic shielding member. Thus, even if there is an external magnetic force outside the housing 30, it is possible to prevent the external magnetic force from affecting the magnetic circuit formed by the magnetic force generating mechanism 22, thereby enabling the shape of the surface of the object to be measured to be measured with high accuracy.

[0106] In addition, in the three-dimensional measurement probe 1 of the present embodiment, the gel body 42 of the vibration damping mechanism 40 is formed of an ultraviolet curing resin.

[0107] With this structure, the gel body 42 can be formed by applying the liquid ultraviolet curing resin to a predetermined position and curing it with ultraviolet rays.

[0108] In the three-dimensional measurement probe 1 of the above embodiment, the housing 30 is configured to be separable into two in a uniaxial direction (Z-axis direction) which is a direction in which the movable body 10 moves, at the position of the first holder 60 that holds the gel body 42. Specifically, the housing 30 can be separated into the first housing portion 31 and the second housing portion 32.

[0109] When the gel body 42 is composed of a light-curing resin such as an ultraviolet curing resin, it is necessary to cure the light-curing resin by irradiating light. Figure 6 As shown, the photocurable resin can be easily injected into the through hole 61 of the first holder 60 by using the dispenser 100, and the injected photocurable resin can be easily cured by light such as ultraviolet rays to form the gel 42. That is, by making the housing 30 separable up and down, the operation of forming the gel 42 in the first holder 60 in the housing 30 can be easily performed.

[0110] In addition, as described above, the damping force generated by the vibration damping mechanism 40 is 1×10 -4 N or less is very small, and the vibration damping mechanism 40 needs to generate this minute damping force with high accuracy. However, by using the dispenser 100 , a fixed amount of ultraviolet curing resin can be easily injected into the through hole 61 .

[0111] (Variation Example)

[0112] As mentioned above, although the three-dimensional measurement probe and the like of the present invention have been described based on the embodiments, the present invention is not limited to the above-mentioned embodiments.

[0113] For example, the methods obtained by implementing various modifications thought of by those skilled in the art to the above-mentioned embodiments, and the methods realized by arbitrarily combining the structural elements and functions in the embodiments within the scope not departing from the gist of the present invention are also included in the present invention. In addition, the technical solutions obtained by arbitrarily combining two or more technical solutions from the multiple technical solutions recorded in the technical solutions at the time of the present application within the scope of technical non-contradiction are also included in the present invention. For example, when the cited technical solutions recorded in the technical solutions at the time of the present application are set as multiple technical solutions or multiple technical solutions citing multiple technical solutions by citing all the upper technical solutions within the scope of technical non-contradiction, the combination of all technical solutions included in the multiple technical solutions or multiple technical solutions citing multiple technical solutions is also included in the present invention.

[0114] Industrial Applicability

[0115] The technology of the present invention is useful as a three-dimensional measurement probe for measuring an object to be measured, such as an optical component or a mold.

Claims

1. A three-dimensional measurement probe, wherein: The three-dimensional measurement probe comprises: A movable body having a stylus whose front end contacts the surface of the object to be measured; a holding mechanism that holds the movable body in such a manner that the movable body can move in a one-axis direction; a housing that accommodates the movable body and the retaining mechanism; as well as a vibration damping mechanism for damping the vibration of the movable body, The vibration damping mechanism includes a pin that moves in the one-axis direction in conjunction with the movement of the movable body, and a gel body that includes a first plane and a second plane that are opposite to each other in the one-axis direction. The first plane and the second plane are exposed surfaces exposed to the air layer. The pin is inserted into the gel body in the one-axis direction.

2. The three-dimensional measurement probe according to claim 1, wherein: The pin extends through the gel body.

3. The three-dimensional measurement probe according to claim 1 or 2, wherein: The vibration damping mechanism has two of the pins and two of the gel bodies, The two pins and the two gel bodies are arranged so as to sandwich the contact pin in a plan view.

4. The three-dimensional measurement probe according to claim 1 or 2, wherein: The holding mechanism includes a bearing that supports the movable body, and a magnetic force generating mechanism that generates a magnetic force that causes the movable body to float.

5. The three-dimensional measurement probe according to claim 4, wherein: The shell is made of magnetic material.

6. The three-dimensional measurement probe according to claim 4, wherein: The bearing is a gas bearing.

7. The three-dimensional measurement probe according to claim 1 or 2, wherein: The gel is composed of ultraviolet curing resin.

8. The three-dimensional measurement probe according to claim 7, wherein: The gel is held by a holding member fixed to the housing. The housing is configured to be separable into two in the uniaxial direction at the position of the holder.

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