JP6673716B2 - Safety scanner - Google Patents

Description

  The present invention relates to a safety scanner, and more particularly, to an improvement in a safety scanner that optically detects an intruder in a protected area.

  The optical safety sensor is an area monitoring device that optically detects an intruder, for example, a person, that has entered a protected area, and outputs a safety control signal for urgently stopping a machine such as a machine tool or an industrial robot. (For example, Patent Documents 1 and 2). For example, a safety scanner emits detection light from a light source to a detection area and scans the detection light in a circumferential direction, and reflected light from an object in the detection area via the optical rotator. A light-receiving element that receives light and generates a light-receiving signal.Based on the light-receiving signal, a distance measurement position corresponding to the distance to the object and the scanning angle of the detection light is obtained, and the distance is measured by comparing with a predetermined protection area. This is an optical scanning area monitoring device including an intruding object discriminating means for discriminating the presence or absence of an object.

JP 2009-296087 A JP 2009-294733 A JP 2009-63339 A

  Usually, the light receiving element has a light receiving surface perpendicular to the rotation axis and is arranged on the rotation axis. On the other hand, the optical rotator is an optical system that rotates about an axis of rotation in the vertical direction, and a light-emitting mirror that turns detection light incident from above by 90 ° and a light-receiving mirror that collects light reflected from an object. It has a lens and a light receiving mirror that reflects reflected light transmitted through the light receiving lens toward the light receiving surface (for example, Patent Document 3).

  In a conventional safety scanner, a light receiving mirror is arranged on a rotation axis, and a reflection surface is inclined at 45 ° with respect to the rotation axis. For this reason, there has been a problem that the rotation radius of the optical rotator becomes large. In particular, the light receiving lens and the light receiving mirror need to be arranged apart from each other. For this reason, in order to prevent the light receiving lens from interfering with the housing during rotation of the optical rotator, the rotation axis must be arranged away from the housing, and there is a problem that the device becomes large. .

  Further, in a conventional safety scanner, an emission optical axis of detection light and an incident optical axis of light reflected from an object are aligned by disposing a light projecting mirror and a light receiving mirror on a rotation axis. For this reason, there is a problem that the shapes of the light projecting mirror and the light receiving mirror are complicated.

  The present invention has been made in view of the above circumstances, and has as its object to provide a safety scanner that can be reduced in size. In particular, it is an object of the present invention to provide a safety scanner that can reduce the rotation radius of the optical rotator.

  The safety scanner according to the first aspect of the present invention is an optical rotator that rotates about a rotation axis, emits detection light from a light source to a detection area, and scans the detection light in a circumferential direction; A light receiving element that receives reflected light from the object in the detection area via the optical rotator and generates a light reception signal; and a distance to the object and a scan angle of the detection light based on the light reception signal. And an intruder discriminating means for determining the distance measurement position corresponding to the intruder, and comparing it with a predetermined protected area to determine the presence or absence of an intruder. The light receiving element has a light receiving surface perpendicular to the rotation axis, and is arranged on the rotation axis. The optical rotator has a light-receiving mirror that reflects the reflected light toward the light-receiving surface, and the light-receiving mirror is offset with respect to the rotation axis on a side opposite to an emission side of the detection light, The tilt angle is greater than 45 °.

  According to such a configuration, since the light receiving mirror is offsetly arranged on the side opposite to the emission side of the detection light and the inclination angle with respect to the rotation axis is larger than 45 °, compared with the case where the light receiving mirror is arranged on the rotation axis. In addition, the radius of rotation of the optical rotator can be reduced.

  In a safety scanner according to a second aspect of the present invention, in addition to the above configuration, the optical rotator further has a light receiving lens for condensing the reflected light, the light receiving mirror is a plane mirror, and the light receiving lens Is configured to reflect reflected light transmitted through the light-receiving surface toward the light-receiving surface.

  According to such a configuration, when the light receiving lens and the light receiving mirror are arranged to be separated from each other, the light receiving mirror is arranged offset, so that the light receiving lens can be closer to the rotation axis. For this reason, an increase in the size of the device can be suppressed. Further, since the light receiving mirror is disposed downstream of the light receiving lens, the size of the light receiving mirror can be reduced.

  A safety scanner according to a third aspect of the present invention includes, in addition to the above configuration, a protective cover for protecting the optical rotator, wherein the protective cover has a window for transmitting the detection light and the reflected light. The window section has a circular section cut by a plane perpendicular to the rotation axis, the section cut by a plane including the rotation axis is linear, and the light receiving mirror has a shape corresponding to the window section. It is constituted to consist of. According to such a configuration, it is possible to reduce the size of the safety scanner while preventing interference between the light receiving mirror and the protective cover.

  A safety scanner according to a fourth aspect of the present invention, in addition to the above configuration, wherein the light receiving mirror is a concave mirror having a concave reflecting surface, and reflects the reflected light toward the light receiving surface. It is configured to focus light on the top. According to such a configuration, a sufficient amount of received light can be obtained without using a light receiving lens.

  In a safety scanner according to a fifth aspect of the present invention, in addition to the above configuration, the optical rotator further includes a light projecting mirror for turning detection light incident from a direction opposite to the light receiving surface by 90 °. It is composed of

  According to such a configuration, the output optical axis of the detection light and the incident optical axis of the reflected light from the object can be substantially matched without disposing the light receiving mirror on the rotation axis. Therefore, it is possible to suppress the shapes of the light projecting mirror and the light receiving mirror from being complicated.

  The safety scanner according to a sixth aspect of the present invention, in addition to the above configuration, is configured such that the light receiving mirror is arranged so as not to overlap with the light projecting mirror when viewed from the direction of the rotation axis. According to such a configuration, since the light receiving mirror can be formed as a member separate from the light projecting mirror, manufacturing of the light projecting mirror and the light receiving mirror can be facilitated.

  A safety scanner according to a seventh aspect of the present invention includes, in addition to the above configuration, a turning mirror that reflects detection light incident from a direction perpendicular to the rotation axis toward the light projecting mirror. According to such a configuration, it is possible to suppress the device from increasing in size in the direction of the rotation axis.

  A safety scanner according to an eighth aspect of the present invention includes a protective cover for protecting the optical rotator, in addition to the above configuration, wherein the protective cover has a window for transmitting the detection light and the reflected light. The window portion has an arcuate section cut by a plane perpendicular to the rotation axis, the section cut by a plane including the rotation axis is linear, and the optical rotator further includes a light receiving mirror. It has a cylindrical lens for forming an image of the reflected light on the light receiving surface, and the cylindrical lens is configured to have a cylindrical surface curved vertically.

  According to such a configuration, since the focusing position in the vertical direction can be adjusted by the cylindrical lens, the curvature of the window portion is significantly different between the scanning direction of the detection light and the vertical direction, Defocusing due to the position on the light receiving surface of the light receiving element can be suppressed.

  According to the present invention, the radius of rotation of the optical rotator can be reduced as compared with the case where the light receiving mirror is arranged on the rotation axis, so that a safety scanner that can be downsized can be provided.

FIG. 1 is a system diagram showing a configuration example of an optical safety system 1 including a safety scanner 10 according to an embodiment of the present invention. FIG. 2 is a front view illustrating a configuration example of the safety scanner 10 of FIG. 1. FIG. 2 is a block diagram showing an example of a functional configuration in the safety scanner 10 of FIG. FIG. 3 is a perspective view illustrating a measurement unit 12 of FIG. 2. FIG. 5 is a perspective view when the protective cover 121 of FIG. 4 is removed from the measurement housing 120. FIG. 5 is an explanatory diagram showing the measurement unit 12 of FIG. 4 in an expanded manner. FIG. 3 is a perspective view showing a configuration example of an optical component 140. FIG. 3 is a perspective view illustrating a configuration example of a frame unit 141. FIG. 4 is a diagram illustrating a case where the protective cover 121 and the optical rotating body 30 are viewed from above. It is the side view which showed the case where the measurement housing | casing 120 was seen from the right direction. It is sectional drawing which showed the cut surface at the time of cutting the measurement housing | casing 120 of FIG. 10 by the AA cutting line. FIG. 11 is a cross-sectional view illustrating a cut surface when the measurement housing 120 in FIG. 10 is cut along a BB cutting line. FIG. 3 is an explanatory diagram schematically showing a state in which a protective cover 121 is attached to and detached from a measurement housing 120. FIG. 6 is an explanatory diagram schematically illustrating a configuration example of a transmittance monitoring mechanism for monitoring the transmittance of a window unit in FIG. 5. FIG. 6 is a diagram illustrating a configuration example of an optical rotator 30 in FIG. 5. It is sectional drawing which showed the cut surface when measuring case 120 is cut | disconnected by the vertical surface containing the rotation axis J. FIG. 17 is an explanatory diagram schematically showing the optical system of FIG. 16. FIG. 17 is a front view showing the light projecting mirror 36 and the light receiving mirror 37 of FIG. 16.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this specification, for convenience, the direction of the rotation axis of the optical rotator will be described as an up-down direction (vertical direction), but the posture at the time of using the safety scanner according to the present invention is not limited. First, a schematic configuration of an optical safety system based on the present invention will be described below with reference to FIGS.

<Optical safety system 1>
FIG. 1 is a system diagram showing one configuration example of an optical safety system 1 including a safety scanner 10 according to an embodiment of the present invention. The optical safety system 1 includes a safety scanner 10 that detects an intruder in a protected area and outputs a detection signal, and a setting support device 20 that generates setting data for the safety scanner. The safety scanner 10 and the setting support device 20 are connected to each other via the communication cable 2.

  The detection signal is a safety control signal for urgently stopping a machine such as a machine tool or an industrial robot. This detection signal is output to a safety control device (not shown) that controls the machine, for example, a PLC (programmable logic controller). By switching the output state of the detection signal to the off state, the operation of the machine to be controlled by the safety control device can be stopped.

  The protection area is an area to be monitored for intrusion detection. For example, an area around machine equipment, such as a work area of a machine tool or an industrial robot, or a moving area of a transport vehicle, is designated as a protected area.

  The safety scanner 10 is a light-scanning safety sensor that optically detects an intruder in a protected area, and includes a display unit 11 and a measurement unit 12. The display unit 11 is a user interface unit that receives a user operation and displays an operation state, setting data, and the like, and includes a connection port for the communication cable 2, an output port for a safety control signal, and the like.

  The measurement unit 12 is a sensor head unit that emits detection light to a detection area, receives reflected light from an object in the detection area, and detects an intruder. The detection area is the largest area that can be detected by the measurement unit 12. The protection area is an area specified in the detection area.

  A warning area other than the protection area can be set in the safety scanner 10. When the safety scanner 10 detects an intruder in the warning area, it outputs an auxiliary output signal and notifies the user by turning on an indicator light or the like.

  For example, the measurement unit 12 is installed on a horizontal floor or the like. The display unit 11 has an OSSD (Output Signal Switching Device), and when there is no intruder in the protected area, the OSSD is turned on and a detection signal of the on state is output. On the other hand, when there is an intruder in the protected area, the OSSD is turned off, and a detection signal of the off state is output.

  The setting support device 20 is an information processing terminal including a display 21, a keyboard 22, and a mouse 23, for example, a personal computer. For example, in the setting support device 20, setting data for designating a protection area and a measurement condition is created. The setting data includes area designation information for designating a protected area and measurement setting information for designating measurement conditions. The setting support device 20 performs an operation of acquiring distance measurement information and a camera image from the safety scanner 10 and displaying the acquired information on the display 21.

<Safety scanner 10>
FIG. 2 is a front view showing an example of the configuration of the safety scanner 10 shown in FIG. 1, and shows a separate type safety sensor that can separate the display unit 11 from the measurement unit 12. The figure shows a case where the safety scanner 10 is viewed from the front. The display unit 11 and the measurement unit 12 are connected to each other via a wiring cable (not shown). Two or more measurement units 12 can be connected to the display unit 11 at the same time.

  An optical rotating body, which will be described later, is disposed in the measuring housing 120 of the measuring unit 12, and a protective cover 121 for protecting the optical rotating body is attached. The optical rotator emits the detection light in the horizontal direction and scans the detection light along the horizontal scan surface 3. The scan plane 3 is a plane orthogonal to the rotation axis of the optical rotator.

  As the detection light, for example, laser light having a wavelength in the infrared region is used. The detection light is repeatedly scanned at a constant scanning cycle. Further, pulsed detection light is generated at regular time intervals. The protective cover 121 is a shield member that protects the optical system including the optical rotating body, and is detachably attached to the measurement housing 120 from the front.

  The measurement housing 120 is provided with two fixed cameras 122 and 123 and an indicator lamp 124 for displaying an output state of a detection signal. The fixed cameras 122 and 123 and the indicator lamp 124 are arranged above the optical rotating body. Note that the fixed cameras 122 and 123 and the indicator lamp 124 may be arranged below the optical rotating body.

  Each of the fixed cameras 122 and 123 is an imaging device that captures a protected area and generates a camera image, and is arranged in different directions. The fixed camera 122 is disposed on the left side of the indicator light 124 when viewed from the direction toward the measurement unit 12. On the other hand, the fixed camera 123 is disposed on the right side of the indicator lamp 124 when viewed from the direction toward the measurement unit 12. That is, the fixed cameras 122 and 123 are arranged so that their positions in the circumferential direction are different from the rotation axis of the optical rotator, and the fixed camera 122 The fixed camera 123 is a camera that fits an area on the left side of the front-rear direction when viewed from the measurement unit 12 within the angle of view, whereas the fixed camera 123 is a camera that fits inside the camera. Since the fixed cameras 122 and 123 are arranged above the scan plane 3, it is possible to obtain a camera image that overlooks the scan plane 3.

  The fixed cameras 122 and 123 preferably photograph not only the protected area but also the periphery of the protected area. Alternatively, the fixed cameras 122 and 123 more preferably photograph an area that can be set as a warning area and its periphery.

  The indicator lamp 124 is an LED indicator that displays an output state and an operation state of the detection signal. The indicator light 124 lights up in different display colors according to the output state of the detection signal. For example, the indicator light 124 lights up in red when the OSSD is off, and lights up in green when the OSSD is on.

  The display unit 11 is arranged on the upper surface of the measurement unit 12. The display panel 110 of the display unit 11 is provided with a display panel 111, an indicator light 112, operation keys 113, and a cable connection port 114.

  The display panel 111 is a display device that displays an operation state, distance measurement information, a camera image, setting data, and the like on a screen. For example, the display panel 111 is an LCD (liquid crystal display) panel. The indicator light 112 is an LED indicator for displaying an operation state, a detection signal output state, and the like. The display unit 11 communicates with the measurement unit 12, and can check the operation state and the detection history of the intruder even at a position separated from the measurement unit 12. The cable connection port 114 is an input / output terminal to which the communication cable 2 is detachably connected.

  FIG. 3 is a block diagram showing an example of a functional configuration in the safety scanner 10 of FIG. The safety scanner 10 includes an optical rotator 30, a light source for light emission 50, a light receiving element 53, a control unit 100, a light emission control unit 101, an angle calculation unit 102, a distance calculation unit 103, an intruder discrimination unit 104, a memory 105, It comprises an external output port 106, an external communication port 107, a display panel 111, indicator lights 112 and 124, and fixed cameras 122 and 123.

  The light projecting light source 50 includes a light emitting element such as an LD (laser diode) or an LED (light emitting diode), and generates detection light. The light emission control unit 101 controls the light emission light source 50 to generate pulsed detection light at regular time intervals. The optical rotator 30 emits the detection light toward the object, and scans the detection light in the circumferential direction about the rotation axis.

  The light receiving element 53 is formed of a photoelectric conversion element such as a PD (photodiode), and receives light reflected from an object via the optical rotator 30 to generate a light receiving signal. The angle calculator 102 detects the rotation of the optical rotator 30 and calculates the scanning angle of the detected light. The light emission control unit 101 controls the light emission light source 50 based on the detection signal from the angle calculation unit 102, and adjusts the light emission timing of the detection light. For example, each time the optical rotating body 30 rotates by 360 ° / 1000, the detection light is emitted.

  The distance calculation unit 103 calculates the distance to the object based on the light receiving signal from the light receiving element 53. The distance calculation unit 103 is a measurement unit that performs distance measurement by a TOF (Time Of Flight) method, measures the light reception timing of the light reception signal based on the pulse signal timing of the angle calculation unit 102, and detects the detection light. The distance to the object is calculated as the detection distance by specifying the delay time from when the light is projected to when the reflected light corresponding to the detection light is received.

  The intruder discriminating unit 104 detects an intruder in the protected area based on the distance measurement information corresponding to the detection distance obtained by the distance calculator 103 and the scanning angle of the detection light, and outputs a detection signal. Whether or not an intruder exists in the protected area is determined by identifying the two-dimensional position of the intruder from the detection distance and the scanning angle of the detection light, and comparing the two-dimensional position with the position information of the protected area.

  Further, the intruder discriminating unit 104 detects an intruder in the warning area based on the distance measurement information, and notifies the user when the intruder in the warning area is detected. The warning area is an area to be monitored for intrusion detection, and is specified in the detection area. The user notification is performed, for example, by turning on the display lamps 112 and 124 in a display mode different from that when detecting an intruder in the protected area.

  The external communication port 107 is a communication interface unit that performs communication with the setting support device 20. The external communication port 107 receives setting data from the setting support device 20, and transmits an operation state, distance measurement information, and a camera image to the setting support device 20. . The external output port 106 is an interface unit that outputs an output signal (ON state or OFF state) of the OSSD as a detection signal (safety control signal) to the safety control device. The external output port 106 is configured to transmit an OSSD output signal (ON state or OFF state) to the safety control device as a detection signal (safety control signal) by bidirectional communication with the safety control device. May be.

  The control unit 100 displays the setting data, the operation state, the distance measurement information, and the camera image on the display panel 111, and displays the operation state on the display lamps 112 and 124. The control unit 100 acquires detection information of an intruder, and generates a detection history based on the detection information. The detection history includes the position of the detected intruder (detection position), the time at which the intruder was detected (detection time), and a monitoring image corresponding to the detection time, and these pieces of detection information are used as the detection history. They are stored in association with each other.

  The monitoring images recorded as the detection history include a still image acquired immediately before or immediately after the detection time, and a moving image in which the detection time is included in the acquisition period. For example, a moving image is acquired around a detection time and has a fixed time length. In addition, camera images captured by the fixed cameras 122 and 123 and scan images obtained from distance measurement information are used as these monitoring images.

  For example, the user can arbitrarily select which of a still image and a moving image is to be recorded as a detection history, or which of a camera image and a scanned image is to be recorded as a detection history. By recording a monitoring image composed of a moving image as a detection history, it is easy to identify the state before and after the detection time. On the other hand, by recording a monitoring image including a still image as a detection history, the number of detection histories that can be stored in the memory 105 can be increased. The memory 105 is a nonvolatile storage element built in the safety scanner 10. The memory 105 holds a detection history and the like created by the control unit 100.

  Next, a more detailed configuration of the safety scanner 10 according to the present invention will be described below with reference to FIGS. 4 to 14 mainly show the configuration relating to the protective cover 121, and FIGS. 15 to 18 mainly show the configuration relating to the optical rotator 30.

<Measurement unit 12>
FIG. 4 is a perspective view showing the measurement unit 12 of FIG. 5A and 5B are perspective views when the protective cover 121 is removed from the measurement housing 120. FIG. 5A illustrates the protection cover 121, and FIG. 5B illustrates the measurement housing 120. Have been. FIG. 6 is an explanatory diagram showing the measurement unit 12 in an expanded manner.

  The measurement housing 120 is a U-shaped metal housing, and includes a canopy 131, a connecting part 132, and a bottom 133. The canopy 131 accommodates a light source for light projection and the like. The bottom 133 is opposed to the canopy 131 and houses a light receiving element and the like. The connecting part 132 connects the rear end of the canopy part 131 and the rear end of the bottom part 133. The optical rotator 30 is arranged between the canopy 131 and the bottom 133.

  As shown in FIG. 6, in the safety scanner 10, the optical rotating body 30 is supported at both ends by the upper support portion 14 and the lower support portion 15 attached to the back plate 135. The measurement housing 120 is a molded product in which the canopy 131, the connecting part 132, and the bottom 133 are integrally formed. By attaching the back plate 135 to the measurement case 120, the optical rotator 30 is indirectly positioned with respect to the measurement case 120.

  The shape of the cut surface of the canopy portion 131 and the bottom portion 133 in the horizontal plane is semicircular on the front side with respect to the rotation axis of the optical rotator 30 and rectangular on the rear side with respect to the rotation axis. In addition, the shape of the cut surface when the measurement housing 120 is cut along a vertical plane parallel to the front-rear direction and including the rotation axis of the optical rotator 30 has a U-shape (C-shape). The optical rotator 30 is disposed in this U-shaped space.

  The indicator lamp module 13 is provided on the canopy 131. The indicator light module 13 is made of a resin housing that houses the fixed cameras 122 and 123 and the indicator light 124. A plurality of light receiving elements 41 for monitoring the transmittance of the protective cover 121 are provided on the upper surface of the bottom 133. The light receiving elements 41 are arranged at regular intervals in the circumferential direction around the rotation axis of the optical rotator 30. The connecting portion 132 is provided with a mounting portion 1321, a screw receiving portion 1322, and a pawl hole 1323.

  The attachment portion 1321 is a plate-like fixing portion for fixing the measurement housing 120 to a vertical wall of a building or the like using a screw, and has a shape protruding from a side surface of the connection portion 132. The mounting portion 1321 is provided on each of the right side surface and the left side surface of the connecting portion 132, and two screw holes are formed in the upper and lower portions that penetrate the mounting portion 1321 in the front-rear direction.

  The screw receiving portion 1322 is a fixing portion for screwing a screw for fixing the protective cover 121 to the measurement housing 120 in the front-rear direction. The screw receiving portions 1322 are provided at two upper and lower positions on the right side surface of the connecting portion 132 and at two upper and lower positions on the left side surface.

  The pawl hole 1323 is a recess for accommodating the presser pawl 1412 provided on the protective cover 121, and is recessed rearward. The pawl holes 1323 are provided at the right end and the left end of the front surface of the connecting portion 132, respectively. Three claw holes 1323 are formed at the right end and the left end of the connecting portion 132, respectively.

  On the other hand, the protective cover 121 includes a frame part 141, a window part 142, and a base part 143. The window portion 142 is an optical component that transmits the detection light from the light source for light projection and the reflected light from the object, and has a curved shape that goes behind the optical rotating body 30. The frame part 141 is a holder component that holds the window part 142. The frame portion 141 is provided with a screw pedestal portion 1411, a presser pawl 1412, and a knob portion 1413.

  The screw pedestal portion 1411 is a mounting portion where a screw for fixing the protective cover 121 to the measurement housing 120 is disposed, and has a shape protruding from the side surface of the frame portion 141. The screw pedestal portion 1411 is provided at each of two upper and lower positions on the right side of the frame portion 141 and two upper and lower positions on the left side surface thereof, and has screw holes penetrating the screw pedestal portion 1411 in the front-rear direction. I have.

  The presser pawl 1412 is an engaging portion for pressing the frame portion 141 against the side surface of the measurement housing 120 by engaging with the pawl hole 1323 of the connecting portion 132, and extends rearward from the rear end surface of the frame portion 141. It has a shape protruding toward it. The holding pawls 1412 are provided at the right rear end and the left rear end of the frame portion 141, respectively. On the right rear end and the left rear end of the frame portion 141, three pressing claws 1412 are formed, respectively.

  The knob portion 1413 is a plate-shaped handle portion for gripping the frame portion 141 in the left-right direction when the protective cover 121 is removed, and has a shape protruding from the side surface of the frame portion 141. The knobs 1413 are provided at the right rear end and the left rear end of the frame 141, respectively.

  The base portion 143 is a horseshoe-shaped optical component that contacts the upper surface of the bottom portion 133, and the lower end of the window portion 142 is joined to the inner edge of the base portion 143. The window 142 is held by the frame 141 via the base 143. The base 143 is provided with a plurality of light receiving windows 1431 for transmitting the detection light for monitoring the transmittance. The light receiving windows 1431 are arranged at regular intervals in the circumferential direction around the rotation axis of the optical rotator 30.

  On the side surface of the measurement housing 120, a packing 134 for sealing a U-shaped space is provided. The packing 134 is a seal member disposed between the measurement housing 120 and the frame 141, and has a shape extending along the outer edge of the frame 141.

  By inserting the holding claws 1412 of the frame portion 141 into the corresponding claw holes 1323, the holding claws 1412 receive a reaction force from the connecting portion 132, and the frame portion 141 is pressed against the side surface of the measurement housing 120. Further, in a state where the screw pedestal portion 1411 faces the screw receiving portion 1322, a screw is screwed into the screw receiving portion 1322 via a screw hole of the screw pedestal portion 1411, so that the protective cover 121 is attached to the measurement housing 120. Fixed.

<Optical component 140>
FIG. 7 is a perspective view illustrating a configuration example of the optical component 140. The optical component 140 includes a window portion 142 and a base portion 143, and is formed separately from the frame portion 141. The cut surface of the window portion 142 formed by a plane (horizontal plane) perpendicular to the rotation axis of the optical rotator 30 has an arc shape on the front side of the rotation axis and curves inward on the rear side of the rotation axis. For example, the rear end of the window portion 142 wraps behind the passage area of the optical rotator 30 when viewed from the front. That is, the shape of the cut surface of the window portion 142 is an arc having a central angle exceeding 180 °.

  The window portion 142 has an optical surface 1421 inclined in a conical shape having a vertex below, a mounting portion 1422 for mounting on the frame portion 141, and rear ends of the optical surface 1421 and the mounting portion 1422 behind the base portion 143. And a connecting portion 1423 connected to the end.

  The optical surface 1421 is an outer peripheral surface of the window portion 142, and the shape thereof is such that the diameter of the cut surface monotonically decreases with a substantially constant inclination as the distance from the upper end of the window portion 142 increases. Yes, it is. In other words, the window 142 has a straight section cut by a plane including the rotation axis.

  The attachment portion 1422 is a portion having a shape extending along the upper end of the optical surface 1421. The attachment portion 1422 has an arc shape on the front side with respect to the rotation axis of the optical rotator 30, and has a linear shape on the back side with respect to the rotation axis. The connecting portion 1423 is a plate-shaped portion perpendicular to the front-rear direction.

  The base portion 143 is a horseshoe-shaped portion that opens rearward. The lower end of the window 142 is joined to the inner peripheral edge of the upper surface of the base 143. The outer peripheral surface of the base 143 is joined to the inner peripheral surface of the frame 141.

  The window part 142 is formed separately from the base part 143. For example, the window portion 142 is a resin molded product formed by press working using a mold, and the optical surface 1421, the mounting portion 1422, and the connecting portion 1423 are integrally formed. Each of the window portion 142 and the base portion 143 is formed of a resin material having a light transmitting property. The window 142 and the base 143 are joined to each other via an adhesive.

<Frame part 141>
FIG. 8 is a perspective view illustrating a configuration example of the frame unit 141. The frame unit 141 includes an upper frame 151, a connection frame 152, and a lower frame 153. The upper frame 151 is a part extending along the outer edge of the canopy 131.

  The lower frame 153 is a portion extending along the outer edge of the bottom 133. Each of the upper frame 151 and the lower frame 153 has an arc shape on the front side with respect to the rotation axis of the optical rotator 30 and has a linear shape on the rear side with respect to the rotation axis.

  The connecting frame 152 extends along the outer edge of the connecting portion 132 and connects the rear end of the upper frame 151 and the rear end of the lower frame 153. The connection frames 152 are provided on the right and left sides of the upper frame 151 and the lower frame 153, respectively. The screw pedestal 1411, the presser pawl 1412, and the knob 1413 are provided on the connection frame 152.

  The upper frame 151 and the lower frame 153 are formed with a concave portion 1414 that engages with a stopper for restricting movement of the protective cover 121 in the front direction. The recess 1414 is an engagement hole that faces the side surface of the measurement housing 120 and that is recessed in the left-right direction. The concave portion 1414 is formed at the upper right end of the upper frame 151, the upper left end of the upper frame 151, the lower right end of the lower frame 153, and the lower left end of the lower frame 153, respectively.

  The frame portion 141 is a resin molded product formed by press working using a mold, and the upper frame 151, the connection frame 152, and the lower frame 153 are integrally formed. Further, the frame part 141 is joined to the window part 142 and the base part 143 of the optical component 140 via an adhesive. That is, the base 143 is joined to the lower end of the window 142 via an adhesive, and is joined to the lower frame 153 via an adhesive.

  FIG. 9 is a diagram illustrating a case where the protective cover 121 and the optical rotator 30 are viewed from above. The optical rotator 30 rotates about a rotation axis J. The rotation axis J is a virtual central axis extending in the up-down direction. The window portion 142 of the protective cover 121 has a curved shape in which a cut surface formed by a horizontal plane wraps behind the optical rotator 30 and is formed of an arc having a center angle about the rotation axis J of more than 180 °.

  In this example, the central angle is about 270 ° near the lower end of the window 142, and the central angle is about 220 ° to 230 ° near the upper end of the window 142. Since the window portion 142 has such a curved shape, uniform optical performance can be obtained for a viewing angle φ of 180 ° or more around the rotation axis J.

  The viewing angle φ is represented by a central angle about the rotation axis J, and indicates the maximum range that can be monitored by scanning the detection light DL in the circumferential direction. For example, when the central angle is monitored in a range of −5 ° to 185 ° based on the Y axis in the left-right direction, the viewing angle φ is 190 °. On the other hand, the frame portion 141 of the protective cover 121 has a circular arc shape on the front side X1 with respect to the rotation axis J and a linear shape on the rear side X2 with respect to the rotation axis J.

  The diameter of the cut surface of the window portion 142 is larger than twice the distance from the rotation axis J to the portion of the optical rotator 30 farthest at any position in the vertical direction. Therefore, the optical rotating body 30 can be rotated without interfering with the window portion 142. On the other hand, the distance in the left-right direction of the opening at the rear side X2 of the window 142, that is, the opening width w is 2 times the distance from the rotation axis J to the part of the optical rotator 30 farthest from the rotation axis J at a specific vertical position. Shorter than double. For this reason, when removing the protective cover 121 from the measurement housing 120, there is a possibility that the window portion 142 contacts the optical rotator 30 depending on the orientation of the optical rotator 30.

  Therefore, in the safety scanner 10 according to the present embodiment, the stopper is provided in the measurement housing 120 while reducing the width of the measurement housing 120 in the left-right direction by bringing the window portion 142 as close to the optical rotating body 30 as possible. When the protective cover 121 is removed, the window portion 142 is prevented from coming into contact with the optical rotating body 30.

<Stopper for protective cover>
FIG. 10 is a side view showing a case where the measurement housing 120 with the protective cover 121 mounted is viewed from the right. FIG. 11 is a cross-sectional view showing a cut surface when the measurement housing 120 of FIG. 10 is cut along the AA cutting line. FIG. 12 is a cross-sectional view showing a cut surface when the measurement housing 120 of FIG. 10 is cut along a cutting line BB. FIGS. 11 and 12 show the case where the cut surface is viewed from the direction of the arrow in FIG.

  The connecting portion 132 is opened rearward, and a back plate 135 for closing the opening is attached. The canopy 131 is provided with a stopper 1311 for restricting movement of the protective cover 121 in the front direction (forward direction). The stopper 1311 is a protruding portion that protrudes in the left-right direction from the side surface of the canopy 131, and is provided on each of the right and left sides of the canopy 131.

  Each stopper 1311 engages with a concave portion 1414 provided in the upper frame 151 of the frame portion 141. The shape of the horizontal cut surface of the stopper 1311 is triangular, the slope of the rear inclined surface is larger than that of the front inclined surface, and intersects the side surface of the canopy 131 at substantially right angles.

  The bottom 133 is provided with a stopper 1331 for restricting the movement of the protective cover 121 in the front direction. The stopper 1331 is a protruding portion having a shape protruding in the left-right direction from the side surface of the bottom portion 133, and is provided on the right side surface and the left side surface of the bottom portion 133, respectively.

  Each stopper 1331 engages with a concave portion 1414 provided in the lower frame 153 of the frame portion 141. The shape of the cut surface of the stopper 1331 by the horizontal plane is triangular, and the slope of the front inclined surface and the slope of the rear inclined surface are almost the same.

  FIG. 13 is an explanatory diagram schematically showing a state in which the protective cover 121 is attached to and detached from the measurement housing 120. (A) in the figure shows a case where the protective cover 121 is attached to the measurement housing 120 from the front direction, and (b) shows a case where the protection cover 121 is removed from the measurement housing 120 in the front direction. ing.

  The protective cover 121 is moved rearward relative to the measurement housing 120, and the upper frame 151 and the lower frame 153 of the frame unit 141 are slid along the side surfaces of the canopy 131 and the bottom 133, thereby protecting the protective cover. 121 is mounted on the measurement housing 120.

  On the other hand, when removing the protective cover 121 from the measurement housing 120, it is necessary to expand the frame portion 141 in the left-right direction by pulling the knob portion 1413 of the frame portion 141 in the left-right direction. First, the protective cover 121 is moved forward with respect to the measurement housing 120 in order to pull out the presser pawl 1412 of the frame part 141 from the pawl hole 1323 of the connecting part 132. The stoppers 1311 and 1331 of the canopy 131 and the bottom 133 are in contact with each other, and the forward movement of the protective cover 121 is prevented.

  Therefore, the grip portion 1413 of the frame portion 141 is gripped and pulled in the left-right direction to expand the frame portion 141 in the left-right direction, so that the rear opening of the window 142 is widened in the left-right direction. If the frame portion 141 is slid forward in this state, the rear end of the concave portion 1414 rides on the front ends of the stoppers 1311 and 1331.

  The protrusion lengths of the stoppers 1311 and 1331 are formed such that the opening width w at the rear end of the window portion 142 becomes wider than the width of the passage area of the optical rotating body 30 when the engagement with the concave portion 1414 is released. When the protective cover 121 is removed from the measurement housing 120, the opening on the rear side of the window portion 142 is forcibly expanded in the left-right direction, regardless of the orientation of the optical rotator 30. Contact with the optical rotator 30 can be prevented.

<Transmittance monitoring mechanism 40>
FIG. 14 is an explanatory diagram schematically showing a configuration example of the transmittance monitoring mechanism 40 for monitoring the transmittance of the window unit 142 in FIG. In the drawing, a part of a cut surface when the measurement housing 120 is cut along a vertical plane including the rotation axis J and perpendicular to the front-rear direction is drawn. The transmittance monitoring mechanism 40 is a monitor device that optically monitors the transmittance of the window 142 to detect dirt or damage, and includes a light receiving element 41 and a light emitting element 42, and a monitoring control unit (not shown). You.

  The window portion 142 of the protective cover 121 transmits the detection light DL from the light source for light projection radially outward from the rotation axis J, and transmits the reflected light RL from the object radially inward. Let it. The window portion 142 is inclined such that the farther downward from the upper end, the shorter the distance to the rotation axis J monotonically with a constant inclination. By tilting the window portion 142 in this manner, regular reflection of the detection light DL can be prevented. The light for monitoring the transmittance passes through the window 142 downward.

  The light projecting element 42 is a light emitting element that projects light for detection toward the window 142, and is arranged at an outer edge of the canopy 131. For example, an LED (light emitting diode) is used for the light emitting element 42. The light emitting element 42 is disposed with the light emitting surface facing downward.

  The light receiving element 41 is a photoelectric conversion element that receives the transmitted light TL transmitted through the window part 142 and generates a light receiving signal, and is arranged on the outer edge of the bottom part 133. For example, a PD (photodiode) is used for the light receiving element 41. The light receiving element 41 is arranged so that the light receiving surface faces upward and faces the light emitting surface of the light projecting element 42. The transmitted light TL transmitted through the window 142 is received by the light receiving element 41 via the base 143.

  The monitoring control unit controls light emission and reception, obtains the transmittance of the window unit 142 based on the light receiving signal from the light receiving element 41, compares the transmittance with a determination threshold to determine the presence or absence of a defect, and determines the determination. The result is output as a detection signal. The transmittance is obtained based on, for example, the amount of received light of the transmitted light TL.

<Optical rotator 30>
FIGS. 15A and 15B are diagrams illustrating a configuration example of the optical rotator 30 in FIG. 5. FIG. 15A illustrates a front view of the optical rotator 30, and FIG. Is shown on the right side, and (c) shows the back surface of the optical rotator 30. FIG. 16 is a cross-sectional view illustrating a cut surface when the measurement housing 120 is cut along a vertical plane including the rotation axis J and perpendicular to the left-right direction.

  The optical rotator 30 includes an optical base frame 31, lens barrels 32 and 33, a light receiving lens, a shield plate, a light projecting mirror, a light receiving mirror 37, and a cylindrical lens.

  In the canopy 131, a light source for projection 50, a condenser lens 51, a turning mirror 52, and a motor unit 60 are arranged. The light receiving element 53, the light receiving substrate 54, and the bearing 61 are provided in the bottom portion 133.

  The optical base frame 31 is a holding member that holds the lens barrels 32 and 33, the light receiving lens 34, the shield plate 35, the light projecting mirror 36, the light receiving mirror 37, and the cylindrical lens 38. The light projecting light source 50 includes a light emitting element such as an LD (laser diode) or an LED (light emitting diode), and generates the detection light DL. The light source 50 for light projection is arranged with the light emitting surface facing forward.

  The condenser lens 51 is an optical member for condensing the detection light DL from the light source for projection 50. The detection light DL is converted by the condenser lens 51 into substantially parallel light. The turning mirror 52 is a plate-like reflecting mirror that reflects the detection light DL that has entered from the rear through the condenser lens 51 downward. The turning mirror 52 is disposed in a state of being inclined by 45 ° with respect to the rotation axis J. That is, the inclination angle of the turning mirror 52 with respect to the rotation axis J is approximately 45 °. The lens barrel 32 is a cylindrical optical guide member extending in the vertical direction with the rotation axis J as a central axis, and guides the detection light DL reflected by the turning mirror 52 downward.

  The light projecting mirror 36 is a flat reflecting mirror that turns the detection light DL from the light projecting light source 50 by 90 °. The light projecting mirror 36 is arranged in a state of being inclined by 45 ° with respect to the rotation axis J, and reflects the detection light DL incident from above through the turning mirror 52 in the horizontal direction. The inclination angle of the light projecting mirror 36 with respect to the rotation axis J is approximately 45 °.

  The lens barrel 33 is a cylindrical optical guide member extending in the horizontal direction, and guides the detection light DL reflected by the light projecting mirror 36 in the horizontal direction. The shield plate 35 is a protective cover that closes the opening of the lens barrel 32, and is made of a light-transmitting flat optical member. This shield plate 35 is arranged at the upper end of the lens barrel 32. The detection light DL reflected by the turning mirror 52 enters the light projecting mirror 36 via the shield plate 35.

  The light receiving lens 34 is an optical member that collects the reflected light RL from the object. For example, the light receiving lens 34 is a plano-convex lens, and is arranged with the rotational symmetry axis directed in the horizontal direction. The lens barrel 33 penetrates the light receiving lens 34 and is disposed such that the central axis substantially coincides with the rotationally symmetric axis of the light receiving lens 34.

  The light-receiving mirror 37 is a flat mirror that reflects the reflected light RL transmitted through the light-receiving lens 34 toward the light-receiving element 53. The light receiving mirror 37 is offset from the rotation axis J on the side opposite to the emission side of the detection light DL, and has an inclination angle larger than 45 °. For example, the inclination angle of the light receiving mirror 37 with respect to the rotation axis J is approximately 60 °. In addition, the light receiving mirror 37 has the entire reflecting surface located behind the rotation axis J.

  The optical rotator 30 makes the central axis of the lens barrel 33 substantially coincide with the rotationally symmetric axis of the light receiving lens 34 so that the output optical axis of the detection light DL and the incident optical axis of the reflected light RL become substantially coaxial. It is composed of

  The light receiving element 53 is a photoelectric conversion element that receives reflected light RL from an object in the detection area via the optical rotator 30 and generates a light receiving signal. For example, a PD (photodiode) is used as the light receiving element 53. The light receiving element 53 has a light receiving surface perpendicular to the rotation axis J, and is arranged on the rotation axis J with the light receiving surface facing upward. The rotation axis J passes through the light receiving surface of the light receiving element 53. The light receiving substrate 54 is a circuit substrate on which circuit elements such as the light receiving element 53 are formed.

  The cylindrical lens 38 is an optical member that forms an image of the reflected light RL reflected by the light receiving mirror 37 on the light receiving surface of the light receiving element 53. The cylindrical lens 38 is a focusing lens for adjusting a focusing position for correctly forming the reflected light RL decentered in the vertical direction on the light receiving surface of the light receiving element 53, and has a cylindrical surface curved in the vertical direction. The cylindrical lens 38 is arranged so that the central axis of the cylindrical surface is horizontal.

  The motor unit 60 includes an electric motor that rotates the optical rotator 30 about the rotation axis J, and a bearing that rotatably supports the upper end of the optical rotator 30 about the rotation axis J. The bearing 61 rotatably supports the lower end of the optical rotator 30 about the rotation axis J.

  At the lower end of the window part 142, an adhesive part 16 with the base part 143 is formed. For example, the bonding section 16 is formed along the lower end of the window section 142, and a part of the window section 142 is welded to the base section 143.

  A packing 4 is provided at a joint between the back plate 135 and the measurement housing 120. The packing 4 is a sealing member for sealing, and is arranged along the outer edge of the back plate 135. The packing 5 is also provided at the joint between the indicator light module 13 and the canopy 131. The packing 5 is a sealing member for sealing, and is arranged so as to surround the wiring through hole 17 provided in the canopy 131. In the through hole 17, a communication line with the fixed cameras 122 and 123 and a power line to the indicator lamp 124 are arranged.

  The optical rotator 30 is provided with a balancer 6. The balancer 6 is a weight member for adjusting the balance of the rotational moment. In the optical rotator 30, the light receiving lens 34 and the light receiving mirror 37 are arranged on opposite sides of the rotation axis J to adjust the balance of the rotational moment. The balancer 6 is provided when the balance of the rotational moment cannot be adjusted only by the light receiving lens 34 and the light receiving mirror 37. This balancer 6 is arranged on the back side of the light receiving mirror 37.

  FIG. 17 is an explanatory diagram schematically showing the optical system of FIG. This optical system includes lens barrels 32 and 33, light receiving lens 34, light projecting mirror 36, light receiving mirror 37, cylindrical lens 38, light projecting light source 50, condenser lens 51, turning mirror 52, and light receiving element 53. .

  The detection light DL emitted forward from the light source 50 for light projection enters the turning mirror 52 via the condenser lens 51, and is reflected downward. The light projecting mirror 36 of the optical rotating body 30 reflects the detection light DL incident from above in the horizontal direction.

  By using the condenser lens 51, it is possible to make the light flux of the detection light DL incident on the light projecting mirror 36 thin. By using the turning mirror 52, the height of the canopy 131 in the vertical direction can be reduced. Further, by arranging the reflection surface of the turning mirror 52 on the rotation axis J, it is possible to obtain a light beam that propagates in the vertical direction.

  The reflected light RL that has entered the light receiving lens 34 of the optical rotator 30 from the horizontal direction passes through the light receiving lens 34 and enters the light receiving mirror 37. The light receiving mirror 37 reflects the reflected light RL incident from the horizontal direction toward the light receiving element 53. The light receiving mirror 37 is arranged so as not to overlap with the light projecting mirror 36 when viewed from the direction of the rotation axis J (vertical direction). The cylindrical lens 38 is located between the light receiving mirror 37 and the light receiving element 53, and forms an image of the light RL reflected by the light receiving mirror 37 on the light receiving surface of the light receiving element 53.

  By matching the output optical axis of the detection light DL with the incident optical axis of the reflected light RL, even the reflected light RL diffused in the vertical direction can be received. Further, the size of the light receiving lens 34 can be reduced. By arranging the light-receiving mirror 37 in an offset manner, the light-receiving lens 34 can be arranged closer to the rotation axis J, so that the rotation radius of the optical rotator 30 can be reduced.

  By disposing the light receiving surface of the light receiving element 53 on the rotation axis J, the reflected light RL from the light receiving mirror 37 can be received regardless of the direction of the optical rotator 30. By using the cylindrical lens 38, the reflected light RL decentered in the vertical direction can be correctly imaged on the light receiving surface of the light receiving element 53.

  The window portion 142 of the protective cover 121 has a linear shape in the vertical direction, but has an arc shape in the scanning direction of the detection light DL, and has a lens effect. The cylindrical lens 38 can suppress the occurrence of variation in the focus position of the reflected light RL due to the anisotropy of the optical characteristics of the protective cover 121.

  FIG. 18 is a front view showing the light projecting mirror 36 and the light receiving mirror 37 of FIG. (A) in the figure shows the light projecting mirror 36, and (b) shows the light receiving mirror 37. The light projecting mirror 36 is formed of a rectangular flat plate. On the other hand, the light receiving mirror 37 is a flat plate having a trapezoidal shape with a lower base shorter than the upper base.

  Since the light-receiving mirror 37 is disposed with the reflection surface inclined downward, the light-receiving mirror 37 becomes farther from the rotation axis J as the distance from the upper end in the vertical direction increases. By forming such a light receiving mirror 37 in the shape of an equilateral trapezoid, the size of a portion far from the rotation axis J is reduced, so that the rotation radius of the optical rotator 30 can be further reduced.

  According to the present embodiment, the light receiving mirror 37 is offset on the opposite side to the emission side of the detection light DL, and the inclination angle with respect to the rotation axis J is larger than 45 °. The radius of rotation of the optical rotator 30 can be reduced as compared with the case of disposing.

  Further, when the light receiving lens 34 and the light receiving mirror 37 are arranged to be separated from each other, the light receiving mirror 37 is offset, so that the light receiving lens 34 can be closer to the rotation axis J. For this reason, an increase in the size of the device can be suppressed. Further, since the light receiving mirror 37 is disposed downstream of the light receiving lens 34, the size of the light receiving mirror 37 can be reduced.

  Further, without arranging the light receiving mirror 37 on the rotation axis J, the emission optical axis of the detection light DL and the incident optical axis of the reflection light RL can be made substantially coincident. Therefore, it is possible to prevent the shapes of the light projecting mirror 36 and the light receiving mirror 37 from becoming complicated. In particular, since the light receiving mirror 37 can be formed as a member separate from the light projecting mirror 36, the manufacture of the light projecting mirror 36 and the light receiving mirror 37 can be facilitated.

  In the safety scanner 10 according to the present embodiment, the window portion 142 of the protective cover 121 has a curved shape in which a cut surface of a plane perpendicular to the rotation axis J of the optical rotator 30 goes behind the optical rotator 30. Therefore, uniform optical performance can be obtained for a viewing angle of 180 ° or more. Therefore, the detectable distance can be increased.

  When the protective cover 121 is removed from the measurement housing 120, the frame portion 141 is expanded in the left-right direction, so that the protective cover 121 can be removed without the window portion 142 interfering with the optical rotating body 30. Further, since the rear end of the concave portion 1414 rides on the stoppers 1311 and 1331 to prevent interference with the optical rotating body 30 by utilizing the fact that the frame portion 141 is expanded in the left-right direction, the safety scanner 10 has a large size. Can be suppressed.

  In addition, since the frame portion 141, the window portion 142, and the base portion 143 can be individually molded, manufacturing of the protective cover 121 can be facilitated. Further, the window portion 142 and the frame portion 141 can be formed of different materials. For example, the window 142 is formed of a material having a higher transmittance than the frame 141. On the other hand, the frame part 141 is formed of a material having higher rigidity than the window part 142.

  Further, by forming the frame portion 141 separately from the optical component 140, the optical performance of the optical component 140 can be improved, and a parting line can be hardly generated in the optical component 140. Further, by forming the frame portion 141 as a component separate from the optical component 140, the protective cover 121 can be firmly fixed to the measurement housing 120, and the waterproof performance can be improved.

  In addition, since the focusing position in the vertical direction can be adjusted by the cylindrical lens 38, the curvature of the window portion 142 is greatly different between the scanning direction of the detection light DL and the vertical direction, so that the light receiving element 53 Can be suppressed from being out of focus depending on the position on the light receiving surface. Further, by disposing the cylindrical lens 38 on the downstream side of the light receiving lens 34, the size of the cylindrical lens 38 can be reduced, so that the radius of rotation of the optical rotator 30 can be further reduced.

  Note that, in the present embodiment, an example has been described in which the safety scanner 10 is a separation-type safety sensor capable of separating the display unit 11 from the measurement unit 12, but the present invention employs the display unit 11 as a measurement unit. The present invention can also be applied to a non-separable type safety scanner which cannot be separated from the scanner 12. For example, the present invention can be applied to a safety scanner in which the display panel 111, the operation keys 113, the cable connection port 114, the output port of the detection signal, and the like are provided in any of the canopy 131, the connecting part 132, or the bottom 133.

  Further, in the present embodiment, an example in which the light receiving lens 34 condenses the reflected light RL has been described, but the present invention does not limit the configuration of the light receiving system of the reflected light RL to this. For example, the optical rotator 30 does not include the light-receiving lens 34, and the light-receiving mirror is a concave mirror having a concave reflecting surface, and reflects the reflected light RL toward the light-receiving surface of the light-receiving element 53. It may be configured to collect light. According to such a configuration, a sufficient amount of received light can be obtained without using a light receiving lens.

  Further, in the present embodiment, an example has been described in which the frame portion 141, the window portion 142, and the base portion 143 are joined to each other via an adhesive, but the present invention limits the configuration of the protective cover 121 to this. It does not do. For example, the frame portion 141 and the window portion 142 may be integrally formed as one resin molded product, and the resin molded product and the base portion 143 may be joined via an adhesive. Further, the window portion 142 and the base portion 143 may be integrally formed as one resin molded product, and the resin molded product and the frame portion 141 may be joined via an adhesive. Further, the base portion 143 and the frame portion 141 may be integrally formed as one resin molded product, and the resin molded product and the window portion 142 may be joined via an adhesive.

  Further, in the present embodiment, an example in which the stoppers 1311 and 1331 are provided on the canopy 131 and the bottom 133, respectively, has been described. However, the present invention restricts the configuration of the stopper for restricting the movement of the protective cover 121 to this. It does not do. For example, the frame portion 141 of the protective cover 121 has a stopper for restricting the movement of the protective cover 121 in the front direction with respect to the measurement housing 120, and the stopper has a shape protruding left and right from the inner surface of the protective cover. , Are arranged to face the left side surface and the right side surface of the canopy portion 131 or the bottom portion 133, respectively, and engage with the concave portions provided on the left side surface and the right side surface of the canopy portion 131 or the bottom portion 133, respectively.

  According to such a configuration, since the stopper of the frame portion 141 has a shape protruding in the left-right direction, the protective cover 121 can be removed from the measurement housing 120 by expanding the frame portion 141 in the left-right direction. It is necessary to release the engagement with the concave portion of the canopy 131 or the bottom 133. That is, when removing the protective cover 121 from the measurement housing 120, the frame portion 141 is expanded in the left-right direction, so that the protective cover 121 can be removed without the window portion 142 interfering with the optical rotating body 30. In addition, since the front end of the concave portion of the canopy 131 or the bottom 133 rides on the stopper of the frame 141, the frame 141 is expanded in the left-right direction to prevent interference with the optical rotating body 30. In addition, an increase in the size of the safety scanner 10 can be suppressed.

  Further, in the present embodiment, an example in which the frame unit 141 includes the upper frame 151, the connection frame 152, and the lower frame 153 has been described, but the present invention does not limit the configuration of the frame unit 141 to this. Absent. For example, the frame portion 141 includes an upper frame extending along the outer edge of the canopy portion 131, and a connecting frame extending along the outer edge of the connecting portion 132 and connecting the rear end of the upper frame and the rear end of the base portion. You. The window and the frame are joined to the base via an adhesive. According to such a configuration, the window portion, the frame portion, and the base portion can be separately molded, so that the production of the protective cover 121 can be facilitated.

  Further, in the present embodiment, an example has been described in which the measurement housing 120 is a molded product in which the canopy 131, the connection portion 132, and the bottom 133 are integrally formed. Is not limited to this. For example, the configuration may be such that the canopy 131, the connecting part 132, and the bottom part 133 are individually formed as an upper housing, a connecting housing, and a lower housing, respectively.

  Further, in the present embodiment, an example has been described in which the optical rotator 30 is rotatably supported by the upper support portion 14 and the lower support portion 15 attached to the back plate 135. However, the support mechanism of the optical rotator 30 is not limited to this. For example, the optical rotator 30 may be configured to be rotatably supported by the canopy 131 (upper case) and the bottom 133 (lower case). The present invention is also applicable to a case where the optical rotating body 30 is supported in a cantilever manner.

DESCRIPTION OF SYMBOLS 1 Optical safety system 10 Safety scanner 11 Display unit 110 Display case 111 Display panel 112 Indicator light 113 Operation key 114 Cable connection port 12 Measurement unit 120 Measurement case 121 Protective covers 122 and 123 Fixed camera 124 Indicator light 13 Indicator light module 131 Top cover 1311, 1331 Protective cover stopper 132 Connecting part 1321 Mounting part 1322 Screw receiving part 1323 Pawl hole 133 Bottom part 134 Seal packing 135 Back plate 14 Upper support part 140 Optical component 141 Frame part 1411 Screw base part 1412 Pressing pawl 1413 knob portion 1414 concave portion 142 window portion 1421 optical surface 1422 attaching portion 1423 connecting portion 143 base portion 1431 light receiving window 15 lower supporting portion 151 upper frame 152 connecting frame 153 lower frame Beam 30 optical rotating body 31 optical base frames 32, 33 lens barrel 34 light receiving lens 35 shield plate 36 light emitting mirror 37 light receiving mirror 38 cylindrical lens 4, 5 packing 40 transmittance monitoring mechanism 41 light receiving element 42 light emitting element 50 light emitting Light source 51 Condensing lens 52 Turning mirror 53 Light receiving element 54 Light receiving substrate 6 Balancer 60 Motor unit 61 Bearing J Rotation axis DL Detection light RL from light source for projection Light TL Reflection from object TL Transmitted light through window unit

Claims (8)

A light source for generating detection light,
Rotated about an axis of rotation, with emitted to the detection area of the detection light from the light source, an optical rotator for scanning the detection light in the circumferential direction,
A light-receiving surface disposed on the rotation axis, and having a light-receiving surface perpendicular to the rotation axis, the light-receiving surface receiving reflected light from an object in the detection area via the optical rotator, and receiving a light-receiving signal; A light-receiving element that generates
Intruding object discriminating means for determining a distance to the object and a distance measuring position corresponding to the scanning angle of the detection light based on the light receiving signal, and comparing with a predetermined protection area to determine the presence or absence of an intruding object. equipped with a door,
The optical rotator is
A projection mirror that emits the detection light to the detection area and turns the detection light passing through the rotation axis incident from the light source to scan the detection light in the circumferential direction,
A light receiving lens provided around an optical path of the detection light turned by the light projecting mirror and condensing reflected light from an object in the detection area,
The reflected light condensed by the light receiving lens and a light receiving mirror for reflecting toward the light-receiving surface,
The light receiving lens forms an optical path of the reflected light around the light projecting mirror,
The safety scanner according to claim 1, wherein the light receiving mirror is offset with respect to the rotation axis on a side opposite to an emission side of the detection light, and has an inclination angle larger than 45 °. With a protective cover for protecting the optical rotating body,
The protective cover has a window that transmits the detection light and the reflected light,
The window portion has a circular section cut by a plane perpendicular to the rotation axis, and a linear section cut by a plane including the rotation axis,
The safety scanner according to claim 1 , wherein the light receiving mirror has a shape corresponding to the window portion. The optical rotator further has a first guide member surrounding the detection light turned by the light projecting mirror,
The safety scanner according to claim 1, wherein the light receiving lens is provided around the first guide member. The first guide member is arranged to penetrate the light receiving lens,
The safety scanner according to claim 3, wherein an emission portion of the detection light protrudes toward the detection area side from the light receiving lens. The optical rotator further includes a second guide member surrounding the detection light passing on the rotation axis, and causing the detection light to enter the light projecting mirror via the second guide member. The safety scanner according to claim 1, wherein The second guide member and the light projecting mirror may be arranged between the light receiving lens and the light receiving mirror such that an optical path of the reflected light is provided around the second guide member and the light projecting mirror. 6. The security scanner according to claim 5, wherein the security scanner is arranged at a position where the security scanner is located. The safety scanner according to claim 1 , wherein the light receiving mirror is disposed so as not to overlap with the light projecting mirror when viewed from a direction of the rotation axis. With a protective cover for protecting the optical rotating body,
The protective cover has a window that transmits the detection light and the reflected light,
The window portion has a circular section cut by a plane perpendicular to the rotation axis, and a linear section cut by a plane including the rotation axis,
The optical rotator further includes a cylindrical lens that forms an image of the light reflected by the light receiving mirror on the light receiving surface,
The safety scanner according to any one of claims 1 to 7, wherein the cylindrical lens has a vertically curved cylindrical surface.

Images