JP6670355B2 - Tilt detecting device and rotating laser device - Google Patents

Description

  The present invention relates to a tilt detecting device and a rotating laser device capable of detecting a tilt based on a pattern.

  Encoders such as linear motion encoders and circle encoders are widely used as inclination detecting means used in the inclination detecting device.

  However, in order to increase the inclination detection accuracy, it is necessary to increase the size of the encoder, and it is necessary to detect a portion having a large movement amount, so that it is possible to avoid an increase in the size of the device itself. However, it has been difficult to achieve both miniaturization of the apparatus and high accuracy of tilt detection accuracy.

JP 2000-266545 A

  The present invention has been made in view of the above circumstances, and provides an inclination detecting device and a rotating laser device for reducing the size of the device.

According to the present invention, the fixed portion and the tilting substrate are relatively rotatably provided via a pivot portion, and one of the fixed portion and the tilting substrate is integrally formed with the pivot portion, and the fixed portion and the tilting substrate are tilted. The substrate includes an inclination detection unit provided on a side relatively rotated with respect to the pivot unit, and an angle detection pattern formed on the pivot unit, and the inclination detection unit applies illumination light to the pivot unit. A light source for irradiation, a light receiving element for receiving the illumination light reflected by the pivot unit, an optical system for projecting a pattern image on the light receiving element, and an image projected on the light receiving element when the pivot unit rotates . And a calculating unit for detecting rotation of the pivot unit based on the pattern image .

  Further, according to the present invention, the optical system includes a polarizing plate disposed on an optical axis, a polarizing beam splitter, and a quarter-wave plate, and the polarizing plate, the polarizing beam splitter, and the quarter-wave plate. Tilt detection that irradiates the pivot portion with illumination light via a wave plate and causes the light receiving element to receive the pattern image reflected by the pivot portion through the quarter wave plate and the polarizing beam splitter; It concerns the device.

  Further, in the present invention, the polarizing plate is a polarizing film formed on an incident surface of the polarizing beam splitter, and the 板 wavelength plate is a 波長 wavelength film formed on an emitting surface of the polarizing beam splitter. It relates to an inclination detecting device.

  Still further, the present invention provides a laser projector which is provided to be tiltable, deflects a laser beam in a horizontal direction and rotatively irradiates the laser beam, a tilt section for tilting the laser projector, and a tilt setting section for setting a target tilt angle of the laser projector. A tilt setting portion, wherein the tilt setting portion includes a base plate orthogonal to an axis of the laser projector, a tilt substrate provided to be tiltable with respect to the base plate via a pivot portion, and a tilt substrate. The present invention relates to a rotary laser device provided on a substrate, comprising: a tilt detector configured to detect the level of the tilt substrate; an angle detection pattern formed on the pivot portion; and the tilt detector provided on the tilt substrate. Things.

According to the present invention, the fixed portion and the tilting substrate are provided so as to be relatively rotatable via a pivot portion, and one of the fixed portion and the tilting substrate is integrally formed with the pivot portion, and the fixing portion and The tilt substrate includes a tilt detection unit provided on a side of the tilt substrate that relatively rotates with respect to the pivot unit, and an angle detection pattern formed on the pivot unit, and the tilt detection unit illuminates the pivot unit. A light source for irradiating light, a light receiving element for receiving illumination light reflected by the pivot unit, an optical system for projecting a pattern image on the light receiving element, and projecting on the light receiving element when the pivot unit rotates. because and a calculation portion for detecting the rotation of the pivot portion on the basis of the pattern image that is, the movement amount of the angle detection pattern compared to the amount of movement of the tilting board is small, the pattern image It is possible to reduce the light receiving element for receiving, together with attained a reduction in size and cost, it is possible to detect the inclination angle of the tilting board with high accuracy.

  Further, according to the present invention, the optical system includes a polarizing plate, a polarizing beam splitter, and a quarter-wave plate provided on an optical axis, wherein the polarizing plate, the polarizing beam splitter, The pivot portion is irradiated with illumination light via a quarter-wave plate, and the pattern image reflected by the pivot portion is received by the light receiving element via the quarter-wave plate and the polarizing beam splitter. Therefore, the pattern image is not reflected to the light source side, and illumination light from the light source is not received by the light receiving element, so that the tilt detection operation of the tilt substrate can be stabilized.

  According to the present invention, the polarizing plate is a polarizing film formed on an incident surface of the polarizing beam splitter, and the quarter-wave plate is a quarter-wave film formed on an emitting surface of the polarizing beam splitter. Therefore, the number of parts can be reduced and the size can be further reduced.

  Still further, according to the present invention, a laser projector that is provided to be tiltable, deflects a laser beam in the horizontal direction, and rotates and irradiates the laser beam, a tilt portion that tilts the laser projector, and a tilt that sets a target tilt angle of the laser projector A rotary laser device comprising a setting unit, wherein the tilt setting unit is a base plate orthogonal to the axis of the laser projector, a tilt substrate provided to be tiltable with respect to the base plate via a pivot portion, The tilt substrate is provided on the tilt substrate, the tilt detector for detecting the horizontal level of the tilt substrate, an angle detection pattern formed in the pivot portion, and the tilt detection unit provided on the tilt substrate, the There is no need to provide a mechanism for detecting the tilt of the tilting board, and the number of components is reduced, and an excellent effect of downsizing can be achieved.

1 is a schematic configuration diagram illustrating a tilt detection device according to a first example of the present invention. FIG. 5 is an explanatory diagram illustrating an angle detection pattern formed on a pivot portion of the tilt detection device. FIG. 7 is a schematic configuration diagram illustrating a tilt detection device according to a second example of the present invention. 1 is an example of a rotary laser device to which a tilt detection device according to an embodiment of the present invention is applied. FIG. 5 is a view as viewed in the direction of arrows AA in FIG. 4.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  First, referring to FIG. 1, a description will be given of an inclination detecting apparatus according to a first embodiment of the present invention.

  In FIG. 1, reference numeral 1 denotes a base plate as a fixing portion, and FIG. 1 shows a part of the base plate 1. Reference numeral 2 denotes a tiltable substrate as a movable portion. The tiltable substrate 2 can be tilted with respect to the base plate 1, and a part of the tiltable substrate 2 is shown in FIG. The tilt substrate 2 is provided so as to rotate integrally with the pivot portion 3, and is tiltable relative to the base plate 1.

  The pivot portion 3 is a sphere, and the base plate 1 has a hole. The peripheral surface of the hole has a spherical surface so that the pivot portion 3 fits therein, and the hole serves as a spherical seat 4 of the pivot portion 3. Further, the pivot portion 3 is rotatably fitted to the spherical seat 4, and the tilting board 2 rotates around the pivot portion 3 as a fulcrum. The lower part of the pivot portion 3 is exposed downward when the pivot portion 3 is fitted to the spherical seat 4.

  The tilt detecting device detects a relative tilt between the base plate 1 and the pivot portion 3, and the tilt detecting device includes a tilt detecting portion 5 and a pivot portion 3 provided on the base plate 1. Is formed by the angle detection pattern 6 formed in the first position.

  Hereinafter, the tilt detection unit 5 will be described.

  A light source 7 that emits illumination light, for example, an LED, is provided vertically above the light source 7, a light projecting lens 9, a polarizing plate 11, a polarizing beam splitter 12, a 波長 wavelength plate 13, and a condensing light on a light projecting optical axis 8 of the light source 7. The lens 14 and the angle detection pattern 6 are provided. The light projecting optical axis 8 is set so as to pass through the center of the pivot portion 3.

  The polarizing plate 11 converts illumination light emitted from the light source 7 into, for example, P-polarized illumination light. The polarization beam splitter 12 transmits, for example, P-polarized light and S-polarized light. Has a polarization characteristic of reflecting light.

  The light source 7, the light projecting lens 9, the polarizing plate 11, the polarizing beam splitter 12, the quarter-wave plate 13, and the condenser lens 14 constitute a light projecting optical system 15.

  On the reflection optical axis 16 of the polarization beam splitter 12, an imaging lens 17 and a light receiving element 18 which is a two-dimensional sensor are provided. As the light receiving element 18, for example, a profile sensor which is an aggregate of pixels is used.

  The profile sensor has pixels arranged in a matrix, and can detect the position of an object in the profile sensor based only on information on pixels in each column in two orthogonal directions (X direction and Y direction). Therefore, the profile sensor can easily detect the position of the target in the profile sensor without acquiring information on all pixels.

  Note that a CCD or a CMOS sensor may be used as the light receiving element 18 to acquire information on all pixels and detect the position of an object on the light receiving element 18.

  The light receiving element 18 outputs a light receiving signal to a calculation unit 19, which calculates the position of the object based on the light receiving signal, calculates the displacement of the position of the object, and the direction of the displacement. The tilt angle and the tilt direction of the tilt substrate 2 are detected based on the tilt angle.

  The condenser lens 14, the quarter-wave plate 13, the polarization beam splitter 12, the imaging lens 17, and the light receiving element 18 constitute a light receiving optical system 21. The polarizing plate 11 and the 波長 wavelength plate 13 constitute an optical isolator.

  Next, the angle detection pattern 6 will be described. The angle detection pattern 6 is formed on the lower surface of the pivot portion 3 by a required method such as printing or engraving.

  In the angle detection pattern 6, for example, as shown in FIG. 2, lands 22 are arranged in a lattice shape. Each land 22 has a different dimension in each of the X and Y directions, and the angle detection pattern 6 is configured to include two-dimensional information in the X and Y directions.

  Illumination light emitted from the light source 7 is converted into a parallel light beam by the light projecting lens 9, converted into, for example, P-polarized light while passing through the polarizing plate 11, and transmitted through the polarizing beam splitter 12. The illumination light transmitted through the polarizing beam splitter 12 passes through the 波長 wavelength plate 13, is condensed by the condenser lens 14, and enters the lower surface of the pivot unit 3, that is, the angle detection pattern 6.

  The light reflected on the lower surface of the pivot portion 3, that is, the pattern image of the angle detection pattern 6, passes through the quarter-wave plate 13 again, and is reflected by the polarization beam splitter 12. The illumination light is changed from P-polarized light to S-polarized light by passing through the quarter-wave plate 13 twice.

  The s-polarized illumination light is reflected by the polarization beam splitter 12 and condensed on the light receiving element 18 by the imaging lens 17. Therefore, the condenser lens 14 and the imaging lens 17 function as an imaging lens for projecting the angle detection pattern 6 on the light receiving element 18.

  Incidentally, a lens having a large magnification, such as a hemispherical lens, is used as the imaging lens 17, and the focusing lens 14 has a refractive power for forming an image on the light receiving element 18 by the imaging lens 17 alone. Can be omitted.

  When the tilting substrate 2 is tilted and the pivot portion 3 is relatively rotated with respect to the tilt detection portion 5, the angle detection pattern 6 moves relative to the base plate 1, that is, the tilt detection portion 5. Displace. The displacement of the angle detection pattern 6 changes the projection position of the pattern image of the angle detection pattern 6 received by the light receiving element 18. The calculation unit 19 calculates the displacement of the projection position based on the light receiving signal from the light receiving element 18 and can detect the tilt of the tilting substrate 2 based on the calculation result.

  Note that the inclination of the tilting substrate 2 is detected based on the moving amount and the moving direction of the position of the pattern image on the light receiving element 18 after the inclination with respect to the position of the pattern image on the light receiving element 18 before the inclination. Is also good. Alternatively, a coordinate system and an origin may be set on the light receiving element 18, and the inclination of the tilt substrate 2 may be detected based on the position of the pattern image on the light receiving element 18 with respect to the origin of the coordinate system.

  The pivot portion 3 has no restriction on the rotation direction, and freely rotates in two directions of XY. The light receiving element 18 can detect a two-dimensional displacement of the angle detection pattern 6. As the tilt direction, an X direction, a Y direction, and a combined XY direction can be detected.

  By providing a movable portion, that is, a driving portion for tilting the tilting substrate 2 on the tilting substrate 2, the driving portion sets the tilting substrate 2 to an arbitrary tilt angle based on the tilt detection result of the tilt detection device. Can be tilted.

  FIG. 3 shows an inclination detecting device according to a second embodiment of the present invention. In FIG. 3, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

  In the tilt detection device shown in FIG. 3, the pivot part 3 is provided on the fixed side. The pivot portion 3 is integrated with a column 23 as a fixing portion. The tilting substrate 2 has the pivot portion 3 as a fulcrum, and is relatively rotatable in two horizontal directions with respect to the pivot portion 3.

  The tilt detector 5 is provided on the tilt substrate 2 side, and the tilt substrate 2 and the tilt detector 5 are integrally formed. Therefore, the tilt detecting section 5 is provided so as to be rotatable relative to the pivot section 3. By tilting the tilt substrate 2, the tilt substrate 2 and the tilt detection unit 5 tilt integrally with the pivot unit 3.

  An angle detection pattern 6 is formed on the pivot portion 3. When the tilting substrate 2 rotates relative to the fixed portion, the pivot portion 3 rotates relative to the tilt detecting portion 5 as in the first embodiment. Since the tilting board 2 and the tilt detection unit 5 tilt integrally, the angle detection pattern 6 rotates relative to the tilt detection unit 5 and displaces relatively.

  As in FIG. 1, illumination light is emitted from the light source 7 to the angle detection pattern 6 via the light projecting optical system 15, and a pattern image of the angle detection pattern 6 is projected onto the light receiving element 18 via the light receiving optical system 21. Is done.

  Therefore, the angle detection pattern 6 is displaced with respect to the light receiving element 18, and the inclination of the tilt substrate 2 can be detected based on the displacement of the angle detection pattern 6 with respect to the light receiving element 18.

  By providing a movable portion, that is, a driving portion for tilting the tilting substrate 2 on the tilting substrate 2, the driving portion sets the tilting substrate 2 to an arbitrary tilt angle based on the tilt detection result of the tilt detection device. Can be tilted.

  4 and 5, an example of a surveying instrument to which the inclination detection device is applied will be described. 4 and 5, the same components as those shown in FIG. 3 are denoted by the same reference numerals. In the following description, a rotary laser device 24 will be exemplified as a surveying instrument, and a case will be described in which the tilt detection unit is provided in a tilt setting unit of the rotary laser device 24.

  In the rotary laser device 24, the tilt substrate 2 is movable, and the tilt detector 5 is provided on the tilt substrate 2.

  A truncated conical recess 26 is formed at the center of the casing 25, and a support seat 27 is formed at the center of the recess 26. The support seat 27 is formed by forming a circular through hole 28 in the concave portion 26 and forming a projection 29 which is smoothly raised at a position where the inner periphery of the through hole 28 is equally divided into three.

  A laser projector 31 that emits illumination light is inserted into the through hole 28, and a head 32 of the laser projector 31 is supported by the support seat 27. The lower part of the head 32 is a spherical part 32a having a spherical shape, and the spherical part 32a is slidably abutted on the projection 29, whereby the laser projector 31 is supported so as to be tiltable with respect to a vertical line. You.

  The head 32 is provided with a motor seat 33 extending in the horizontal direction, and the motor seat 33 is provided with a scanning motor 34. A gear 35 is fitted on the output shaft of the scanning motor 34, and the gear 35 meshes with a scanning gear 36 (described later).

  A prism holder 38 is rotatably provided on the head 32 via a bearing 37, and the axis of the prism holder 38 matches the axis of the laser projector 31. The scanning gear 36 is fitted on the prism holder 38, and the scanning gear 36 meshes with the gear 35. The prism holder 38 is rotated about a vertical axis by the scanning motor 34, and the prism holder 38, the scanning gear 36, and the like constitute a rotating part 39. The prism holder 38 is provided with a pentaprism 41 so that the illumination light emitted from the laser projector 31 is deflected in the horizontal direction through a projection window 42 and emitted.

  At the lower end of the laser projector 31, a base plate 43 having a substantially right-angled triangular shape perpendicular to the axis of the laser projector 31 is fixed. The column 23 is erected near a right angle top of the base plate 43, and the pivot portion 3 is fixed to an upper end of the column 23.

  The tilted substrate 2 having a right-angled L shape is disposed above the base plate 43, and a conical spherical seat 44 is formed at the top of the tilted substrate 2 having an L-shaped back surface. The pivot portion 3 is fitted to the spherical seat 44, the column 23 supports the top of the tilting substrate 2 via the pivot portion 3, and the tilting substrate 2 pivots around the pivot portion 3. It is possible.

  Further, the tilt detecting section 5 is provided directly above the pivot section 3 of the tilt substrate 2. The tilt detecting section 5 tilts integrally with the tilt substrate 2 and tilts relatively to the angle detection pattern 6 formed on the upper surface of the pivot section 3.

  Further, the tilting substrate 2 is provided with bubble tubes 45 and 46, which are tilt detectors for detecting horizontality, so as to intersect at right angles. The bubble tubes 45 and 46 are capacitance detection type electric bubble tubes, and output an electric signal corresponding to an inclination angle with respect to a horizontal plane.

  Note that the base plate 43, the tilt substrate 2, the tilt detection unit 5, the bubble tubes 45 and 46, and the angle detection pattern 6 constitute a tilt setting unit.

  Further, a spring 47 is provided between the tilting substrate 2 and the base plate 43 to press the spherical seat 44 against the pivot portion 3 and to urge the tilting substrate 2 clockwise in FIG.

  A bearing plate 48 is provided in the middle of the laser projector 31, and the bearing plate 48 projects horizontally from the laser projector 31. Tilting screws 49 and 51 are rotatably erected on the base plate 43 at positions forming a triangle with the column 23 as the apex, and upper ends of the tilting screws 49 and 51 are rotatably supported on the bearing plate 48, respectively. Have been.

  The lower end of the tilt screw 49 protrudes below the base plate 43, and a tilt gear 52 is fitted to the lower end of the tilt screw 49, and the tilt gear 52 meshes with a tilt gear 53 described later. Similarly, the lower end of the tilt screw 51 projects below the base plate 43, and a tilt gear 54 is fitted to the projecting end of the tilt screw 51, and the tilt gear 54 meshes with a tilt gear 55 described later. .

  A tilting nut 56 is screwed into the tilting screw 49, and a nut pin 57 having a circular cross section is projected from the tilting nut 56 in a horizontal direction. A tilt pin 58 protrudes from an end surface of the tilt board 2 on the tilt screw 49 side, and the tilt pin 58 contacts the nut pin 57. Further, two parallel guide pins 59 are stretched between the base plate 43 and the bearing plate 48. The tilt pins 58 are slidably held by the guide pins 59 to restrict the horizontal rotation of the tilt substrate 2, and the vertical direction of the tilt pins 58 and the axis of the tilt pins 58 are centered. To allow rotation.

  A tilting nut 61 is screwed into the tilting screw 51, and a nut pin 62 having a circular cross section is projected from the tilting nut 61. A tilt pin 63 protrudes from an end surface of the tilt board 2 on the tilt screw 51 side, and the tilt pin 63 contacts the nut pin 62.

  A pillar 64 is suspended from the lower surface of the base plate 43, and a motor base 65 is fixed via the pillar 64. On the upper surface of the motor base 65, tilt angle setting motors 66 and 67, which are pulse motors, are provided. The tilt gear 53 is fitted on the output shaft of the tilt angle setting motor 66, and the output of the tilt angle setting motor 67 is output. The tilt gear 55 is fitted on the shaft, and meshes with the tilt gears 52 and 54, respectively.

  Next, an inclined portion for inclining the laser projector 31 will be described.

  The tilt arms 68 and 69 extend horizontally from the head 32 of the laser projector 31 in a horizontal direction. In FIG. 4, only the tilt arm 68 is shown, and the tilt arm 69 is not shown. The tilting arms 68 and 69 pass through the conical surface of the concave portion 26 and are located inside the casing 25, and engaging pins 71 and 72 are protruded from the tips. In FIG. 4, only the engagement pin 71 is shown, and the illustration of the engagement pin 72 is omitted.

  The engagement pins 71, 72 are cylindrical, and the axes of the engagement pins 71, 72 are orthogonal to each other, and determine the positional relationship such that they are included in a plane passing through the centering of the spherical portion 32a. In addition, one of the engaging pins 71 and 72, for example, the engaging pin 71 is restricted from moving in the horizontal direction, and can be moved only in the vertical direction.

  Shelf plates 73 and 74 are provided on the inner wall of the casing 25, a tilt motor 75 is provided on the shelf plate 73, a tilt motor 76 (not shown) is provided on the shelf plate 74, and the rotation shaft of the tilt motor 75 is driven. A gear 77 is fitted, and a drive gear 78 (not shown) is fitted to the rotation shaft of the tilt motor 76.

  A screw shaft 79 orthogonal to the engaging pin 71 is provided to extend over the ceiling of the casing 25 and the shelf plate 73. A driven gear 81 is fitted to the screw shaft 79, and the driven gear 81 is engaged with the driven gear 81. A slide nut 82 is screwed onto the screw shaft 79, a pin 83 is protruded from the slide nut 82, and the pin 83 and the engaging pin 71 are slidably contacted.

  Similarly, a screw shaft (not shown) orthogonal to the engagement pin 72 is provided so as to span the ceiling of the casing 25 and the shelf plate 74, and a driven gear meshing with the drive gear 78 on the screw shaft. (Not shown) is fitted. Also, a slide nut (not shown) having a pin (not shown) protruding from the screw shaft is screwed into the screw shaft, and the pin and the engaging pin 72 are slidably contacted.

  A spring receiver 84 is provided between the ceiling of the casing 25 and the two screw shafts, and a spring 85 is stretched between the spring receiver 84 and the laser projector 31. The spring 85 urges the laser projector 31 clockwise about the support seat 27 in FIG.

  In FIG. 4, reference numeral 86 denotes a battery box for storing a battery for driving the rotary laser device 24. The main body 87 of the rotary laser device 24 is provided on a tripod (not shown) via a leveling bolt 88. Further, reference numeral 89 denotes a glass window surrounding the periphery of the prism holder 38.

  Next, a description will be given of a case where the direction of projection of the illumination light emitted from the laser projector 31 in the rotary laser device 24 is inclined.

  First, the relative tilt between the tilting substrate 2 and the base plate 43 is set to 0 based on the detection result of the tilt detecting unit 5. That is, the tilt substrate 2 and the base plate 43 are made parallel. At this time, the projection position of the pattern image obtained by the illumination light emitted from the light source 7 of the tilt detection unit 5 and reflected by the angle detection pattern 6 is the origin, for example, the center of the light receiving element 18. The axis of the laser projector 31 is orthogonal to the tilt substrate 2.

  Next, based on the detection results of the bubble tubes 45 and 46, the tilt motors 75 and 76 are driven to tilt the laser projector 31. By tilting the laser projector 31, the bubble tubes 45 and 46 are in a state of detecting horizontality, and the laser projector 31 is leveled. In this state, the laser projector 31 is vertical (the axis of the laser projector 31 is vertical).

  After the laser projector 31 is leveled, the tilt substrate 2 is tilted based on the input tilt value. For example, the tilt angle setting motor 66 is driven by the number of steps corresponding to the tilt value, and the tilt substrate 2 is tilted by a desired angle in a direction opposite to the direction in which the laser projector 31 is tilted. Since the tilt detection unit 5 rotates relatively to the pivot unit 3 by tilting the tilting substrate 2, the pattern image projected on the light receiving element 18 moves and moves to the position of the pattern image. The tilt angle of the tilt substrate 2 can be detected based on the tilt angle.

  After the tilt substrate 2 is tilted, the tilt motor 75 is driven to tilt the laser projector 31 in the desired direction until the bubble tubes 45 and 46 detect horizontality. At this time, since the tilt detecting section 5 and the pivot section 3 are integrally tilted, the result of the tilt detecting section 5 detecting the tilt of the tilting substrate 2 is maintained.

  When the bubble tubes 45 and 46 detect horizontality, the tilt setting of the laser projector 31 is completed, and the tilt setting of the projection direction of the illumination light is completed. In this state, by rotating the pentaprism 41 via the prism holder 38 by the scanning motor 34, a reference plane inclined at a desired angle in a predetermined direction can be formed.

  As described above, in the present embodiment, the angle detection pattern 6 is formed on the pivot portion 3 serving as a fulcrum when the tilt substrate 2 is tilted, and the angle detection pattern 6 is relative to the tilt detection device. The tilt angle of the tilt substrate 2 can be detected based on the amount of movement.

  Accordingly, the amount of movement of the angle detection pattern 6 is significantly smaller than the amount of movement of the tip side of the tilting substrate 2, so that the angle detection pattern 6 can be compared with a case where the amount of movement of the tilting substrate 2 is directly detected. The size of the light receiving element 18 for receiving the pattern image of No. 6 can be reduced, and the manufacturing cost can be reduced.

  Further, since the tilt angle of the tilt substrate 2 is detected based on the projection position of the pattern image of the angle detection pattern 6, there is no need to increase the size for high accuracy unlike the conventional encoder. The size of the device can be reduced, and the inclination can be detected with high accuracy.

  Further, the angle detection pattern 6 is formed on the pivot portion 3 by printing, engraving, exposing, or the like, and only the light receiving position on the light receiving element 18 of the pattern image reflected by the angle detection pattern 6 is detected. Therefore, it is not necessary to separately provide a mechanism for detecting the inclination, and the number of components can be reduced.

  Further, since the angle detection pattern 6 is formed by printing, engraving, or the like on a spherical object, expansion and contraction at the time of environmental temperature change becomes substantially point symmetric, and errors can be minimized.

  Further, since the polarizing plate 11 and the quarter-wave plate 13 form an optical isolator, only the reflected light in a specific polarization direction is received by the light receiving element 18, and a decrease in light amount is suppressed. A pattern image can be detected with an appropriate amount of light, and the tilt detection accuracy of the tilt detection device can be further improved.

  Further, since the pattern image reflected by the angle detection pattern 6 is totally reflected by the polarization beam splitter 12, the pattern image does not pass through the polarization beam splitter 12 and reach the light source 7 side, Further, the illumination light from the light source 7 is not received by the light receiving element 18, and the operation of the tilt detecting device can be stabilized.

  Further, the condensing lens 14 is provided on the light projecting optical axis 8 and the illumination light converted into a parallel light beam by the light projecting lens 9 is condensed on the angle detection pattern 6. Even if the light intensity decreases in the process of passing through 11, the pattern image of the angle detection pattern 6 having a sufficient light intensity can be projected on the light receiving element 18.

  In the present embodiment, the polarizing plate 11 and the quarter-wave plate 13 are provided on the light projecting optical axis 8, and the polarizing plate 11 and the quarter-wave plate 13 form an optical isolator. However, a polarizing film having a polarization characteristic of transmitting only, for example, P-polarized light is deposited on the incident surface of the polarizing beam splitter 12, and a 波長 wavelength film is deposited on the exit surface of the polarizing beam splitter 12, The polarization beam splitter 12 alone may form an optical isolator. In this case, the polarizing plate 11 and the quarter-wave plate 13 can be omitted, and the size of the tilt detection device can be further reduced.

  If the S / N ratio does not cause any particular problem, the optical isolator can be omitted.

Reference Signs List 2 tilting board 3 pivot part 5 tilt detecting part 6 angle detecting pattern 7 light source 8 light projecting optical axis 9 light projecting lens 11 polarizing plate 12 polarizing beam splitter 13 quarter wavelength plate 14 condensing lens 17 imaging lens 18 light receiving element 24 Rotating laser device 31 Laser projector

Claims (4)

A fixed portion and a tilting substrate are provided so as to be relatively rotatable via a pivot portion, and one of the fixed portion and the tilting substrate is integrally formed with the pivot portion, and a part of the pivot portion as a sphere is provided. The fixed portion and the tilting substrate are fitted so as to protrude from one of the other, an angle detection pattern is attached to a protruding surface of the pivot portion, and light from a light source is transmitted to the angle detection pattern via a lens of an optical system. An inclination detection device, wherein the inclination detection device is configured to project and detect the projected angle detection pattern image by a light receiving element .   The optical system includes a polarizing plate disposed on an optical axis, a polarizing beam splitter, and a quarter-wave plate. The polarizing plate, the polarizing beam splitter, and the quarter-wave plate are interposed therebetween. The tilt detecting device according to claim 1, wherein the pivot portion is irradiated with illumination light, and the pattern image reflected by the pivot portion is received by the light receiving element via the quarter-wave plate and the polarizing beam splitter. .   3. The tilt of claim 2, wherein the polarizing plate is a polarizing film formed on an incident surface of the polarizing beam splitter, and the quarter-wave plate is a quarter-wave film formed on an emitting surface of the polarizing beam splitter. Detection device. A rotary laser that is provided to be tiltable, and that has a laser projector that deflects a laser beam in the horizontal direction and irradiates the laser beam for rotation, a tilt unit that tilts the laser projector, and a tilt setting unit that sets a target tilt angle of the laser projector. 4. The apparatus according to claim 1 , wherein the inclination setting unit is a base plate orthogonal to an axis of the laser projector, the inclination detection apparatus according to claim 1 provided on the base plate , and the inclination detection apparatus. rotary laser apparatus characterized by comprising a tilt detector for detecting the horizontal.

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