Imaging apparatus

Abstract

To prevent a situation where a sensor for an encoder and a scale for an encoder collide with each other when an impact is applied to a rotation shaft, in an imaging apparatus without increasing the size thereof.SOLUTION: An imaging apparatus comprises: a camera unit; a rotation shaft that supports the camera unit; a base that holds the rotation shaft in a rotatable state; a sensor substrate that is arranged on the base; a sensor for an encoder that is arranged on the sensor substrate; a scale for an encoder that is held on the rotation shaft at a position facing the sensor for an encoder; and a first stopper that is held on the rotation shaft at a position facing the base. The distance between the sensor for an encoder and the scale for an encoder is made larger than the distance between the first stopper and the base.SELECTED DRAWING: Figure 4A

Description

[Technical Field]

[0001] The present invention relates to an imaging device, and more particularly to a surveillance camera equipped with an encoder on a rotation axis for pan-tilt operation, and an imaging device suitable for positioning the pan-tilt at an accurate angle even when an impact is applied. [Background technology]

[0002] In recent years, pan-tilt cameras have become widely used as surveillance cameras for monitoring purposes. Pan-tilt cameras are equipped with a mechanism that can rotate in the pan direction (horizontal) and tilt direction (vertical), and have the function of automatically circulating between preset positions specified by the user. When specifying a preset position, the camera is instructed to repeatedly return to the same rotation angle. However, backlash (gear misalignment) in the drive system can cause the surveillance camera to stop at a variable angle, resulting in a shift in the captured image, which can prevent the desired image from being captured. Therefore, an encoder is used as a means of detecting the rotation angle to repeatedly stop the camera at the same rotation angle with high precision. The encoder uses a pair of an encoder sensor and an encoder scale, and outputs angle information by reading the change in physical quantity that occurs when the encoder scale is rotated using the encoder sensor.

[0003] Meanwhile, at surveillance sites, the camera unit may be subjected to an impact that disrupts filming. When this happens, the impact is also transmitted to the rotating shaft that holds the camera unit, causing the rotating shaft to momentarily shift or deform. This also causes a shift in the position of the encoder scale attached to the rotating shaft. This shift in position can cause the encoder scale to collide with a nearby encoder sensor, potentially damaging either or both of them and impairing angle detection performance.

[0004] In the vehicle height detection sensor described in Patent Document 1, a magnet is fixed to a rotor that rotates due to the up and down movement of the vehicle body, and the rotation speed is detected by a Hall IC. In Patent Document 1, the cover is positioned at a distance from the encoder sensor. Therefore, when an impact is applied, the cover absorbs the impact first. Even if the cover is deformed by the impact, the distance prevents the cover from colliding with the encoder sensor. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-137986 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the case of a configuration in which a separate cover absorbs the impact as in Patent Document 1, the imaging device becomes large.

[0007] An object of the present invention is to provide an imaging device that can prevent an encoder sensor from colliding with an encoder scale when an impact is applied to a rotating shaft, without increasing the size. [Means for solving the problem]

[0008] The imaging device of the present invention comprises a camera unit, a rotating shaft that supports the camera unit, a base that holds the rotating shaft in a rotatable state, a sensor board arranged on the base, an encoder sensor arranged on the sensor board, an encoder scale held on the rotating shaft at a position opposite the encoder sensor, and a first stopper held on the rotating shaft at a position opposite the base, wherein the distance between the encoder sensor and the encoder scale is greater than the distance between the first stopper and the base. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide an imaging device that can prevent collision between an encoder sensor and an encoder scale when an impact is applied to a rotating shaft, without increasing the size. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a perspective view of an imaging device according to a first embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the periphery of the tilt axis. [Figure 3] FIG. 2 is an exploded perspective view of the periphery of an encoder in the imaging device of the first embodiment. [Figure 4A] 10 is a detailed cross-sectional view of the periphery of the encoder in the imaging device of the first embodiment when the tilt axis is not tilted. FIG. [Figure 4B] 10 is a detailed cross-sectional view of the periphery of the encoder when the tilt axis is tilted due to an external impact or the like in the imaging device of the first embodiment. FIG. [Figure 5] FIG. 10 is an exploded perspective view of the periphery of an encoder in the imaging device of the second embodiment. [Figure 6A] FIG. 10 is a detailed cross-sectional view of the periphery of the encoder in the imaging device of the second embodiment when the tilt axis is not tilted. [Figure 6B] 10 is a detailed cross-sectional view (part 1) of the periphery of the encoder in the imaging device of the second embodiment when the tilt axis is tilted due to an external impact or the like. FIG. [Figure 6C] 10 is a detailed cross-sectional view (part 2) of the periphery of the encoder in the imaging device of the second embodiment when the tilt axis is tilted due to an external impact or the like. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, each embodiment of the present invention will be described with reference to FIGS. 1 to 6C.

[0012] [Embodiment 1] Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 4B. In the following, in this embodiment, a surveillance camera will be taken as an example of an imaging device that performs pan-tilt operations. First, the appearance of the imaging device will be described with reference to FIG. FIG. 1 is a perspective view of an imaging device according to the first embodiment.

[0013] Imaging device 100 is a device that captures moving and still images and records the video data. Imaging device 100 includes a pan base 140 equipped with a side cover 150, which is supported on a fixed portion 160 in a manner that allows it to rotate horizontally (in the pan direction). To withstand impacts described below, pan base 140 is preferably made of a highly rigid material such as die-cast aluminum. Furthermore, pan base 140 supports tilt shaft 130 in a manner that allows it to rotate vertically (in the tilt direction). Camera unit 110 is supported on tilt shaft 130 via camera unit holding member 120, and camera unit 110 includes a lens barrel (not shown) that houses an optical lens. Because camera unit 110 can rotate in the pan direction together with pan base 140 and in the tilt direction together with tilt shaft 130, imaging device 100 is capable of capturing a wide range of images in both the pan and tilt directions.

[0014] Next, the structure around the tilt axis of the imaging device will be described with reference to FIG. FIG. 2 is a cross-sectional view of the vicinity of the tilt axis.

[0015] Here, the rotation drive mechanism for rotating the camera unit 110 in any direction will be described using rotation in the tilt direction as an example. Rotation in the pan direction can also be achieved with a similar drive mechanism.

[0016] The camera unit 110 is electrically connected to a main board 310 via a camera cable 111. The main board 310 is a board on which electronic components for camera control, pan / tilt rotation drive control, power supply, etc. are mounted, and is fixed to the pan base 140 by a board holding member 320. The tilt shaft 130 is rotatably held relative to the pan base 140 via a bearing 210. A driven pulley 220 is held at one end of the tilt shaft 130. A drive pulley 240 is held by a motor 230 fixed to the pan base 140. A toothed belt 250 is attached so as to mesh with the teeth of the drive pulley 240 and the driven pulley 220. The motor 230 is connected to the main board 310 by a motor cable 231, and power is supplied to the motor 230 via the motor cable 231. When motor 230 is driven, the rotational driving force generated by motor 230 is transmitted to driven pulley 220 via toothed belt 250. As a result, tilt shaft 130, which holds driven pulley 220, rotates, making it possible to rotate camera unit 110 in the tilt direction. Note that, in terms of the configuration of the drive system, the rotational driving force of motor 230 may be transmitted to tilt shaft 130 using a transmission component other than a toothed belt, such as a spur gear.

[0017] Next, the structure around the encoder and the state around the encoder when the tilt axis is tilted will be described with reference to FIGS. 3 to 4B. FIG. 3 is an exploded perspective view of the periphery of the encoder in the imaging device of the first embodiment. FIG. 4A is a detailed cross-sectional view of the periphery of the encoder in the imaging device of the first embodiment when the tilt axis is not tilted. FIG. 4B is a detailed cross-sectional view of the periphery of the encoder in the imaging device of the first embodiment when the tilt axis is tilted due to an external impact or the like.

[0018] When a user repeatedly returns to the same rotation angle, the stop angle of the imaging device 100 may vary due to backlash in the drive system. The shooting location may shift each time the stop angle varies, which may result in the desired image not being obtained. Since the angle of view is narrow especially when the focus of the image is on the telephoto side, even a slight deviation in the stop angle may result in a large deviation in the image.

[0019] Therefore, an encoder is sometimes used as a means for detecting the rotation angle in order to repeatedly stop the imaging device 100 at the same rotation angle with high accuracy. By using an encoder, the rotation angle of the imaging device 100 can be detected and the stop angle can be corrected if it deviates from the specified angle. In addition to correction, it is also possible to repeatedly stop the imaging device 100 at the same rotation angle with high accuracy by aiming for the encoder's rotation angle from the beginning. The following explanation uses a magnetic encoder as an example.

[0020] The encoder uses a pair of encoder sensors 411 and encoder scales 510. The magnetic sensor 411 reads changes in the magnetic field distribution that occur when the encoder scales 510 are rotated, thereby outputting angle information. If the gap a between the encoder sensor 411 and the encoder scales 510 shown in FIG. 4A is large, the magnetic field detection sensitivity decreases, resulting in a larger error in the detected rotation angle. If the error in the detected rotation angle increases, variations in the stop angle occur even when the user repeatedly stops at the same rotation angle, resulting in captured images deviating from the desired angle each time. If the gap a becomes even larger, the magnetic field may become insufficient to detect. Conversely, if the gap a is smaller than a predetermined value, the detected magnetic field may become too large and may not be read correctly. Furthermore, if the encoder scales 510 are tilted, the size of the gap a changes depending on the phase, potentially resulting in a larger angle error in some areas. Therefore, the gap a must be set to a uniform and appropriate distance to minimize the detected angle error.

[0021] As shown in the perspective view of FIG. 3 and the cross-sectional view of FIG. 4A, a sensor board 410 on which an encoder sensor 411 is mounted is held by the pan base 140. The sensor board 410 is electrically connected to the main board 310 by a connection means such as a cable or a connector (not shown). Meanwhile, an encoder scale 510 is fixed by press-fitting, adhesive bonding, screwing, or the like to one end of the tilt shaft 130 opposite the driven pulley 220 (see FIG. 2) at a position facing the encoder sensor 411. Therefore, the encoder scale 510 is rotatable together with the camera unit 110 via the tilt shaft 130. The encoder scale 510 is composed of a magnet with alternating south and north poles. When the encoder scale 510 rotates, the magnetic field in the encoder sensor 411, which is fixed to the pan base 140, which is a non-rotating part, changes. The encoder sensor 411 then reads this change in magnetic field distribution and outputs it as angle information. This makes it possible to detect the rotation angle of the camera unit 110 that rotates together with the encoder scale 510.

[0022] A rib-shaped second stopper 141 is formed on the pan base 140, on the outer periphery side of the sensor substrate 410, centered on the axis of the tilt shaft 130. The first stopper 610 is fixed to the tilt shaft 130 by a first fixing member 612 such as a screw so that the first stopper 610 faces the second stopper 141. At this time, the first stopper 610 is arranged so that the gap a between the encoder sensor 411 and the encoder scale 510 is larger than the gap b between the first stopper 610 and the second stopper 141. In this embodiment, the second stopper 141 is formed on the pan base 140, but a rib may be provided on the first stopper 610 side and brought close to the pan base 140.

[0023] As described above, gap a must be set to an appropriate value to minimize the error in the angle detected by the encoder sensor 411. In this case, gap a may be set to a very small distance of 1 mm or less. To avoid impact between the encoder sensor 411 and the encoder scale 510 (described later), gap b must be set to an even smaller gap than gap a, which is 1 mm or less. If multiple components are interposed and the total axial tolerance variation of each component is large, gap b may disappear during assembly (the first stopper 610 and the second stopper 141 may come into contact). If the camera unit 110 is rotated in the tilt direction without gap b, the first stopper 610 and the second stopper 141 will slide against each other. As a result, generated wear debris may interfere with magnetic field reading. Furthermore, wear debris may get between the tilt shaft 130 and the bearing 210, causing problems with rotation and preventing the tilt unit from accurately stopping at the specified angle. There is a risk that gap b will become larger than gap a due to tolerance variations in parts, making it impossible to avoid impact between encoder sensor 411 and encoder scale 510, which will be described later. For this reason, it is preferable to perform assembly in such a way that gap b is adjustable, taking into account the effects of tolerance variations in parts.

[0024] Therefore, in this embodiment, a spacer 611 is disposed between the first stopper 610 and the end face of the tilt shaft 130. A method for adjusting gap b based on this assumption will be described below. First, gap a is measured from the notch 142 formed in the pan base 140 using a gap sensor or the like. Then, the size of gap b is determined to be smaller than this measurement result. Next, the distance between the end face of the tilt shaft 130 (the surface to which the spacer 611 is attached) and the adjacent surface of the second stopper 141 is measured. This measurement result is compared with the determined size of gap b, and a spacer 611 with a thickness that makes up for the shortfall is prepared. Then, with spacer 611 disposed between the first stopper 610 and the end face of the tilt shaft 130, the first stopper 610 is fixed to the tilt shaft 130 with a first fixing member 612.

[0025] As described above, by assembling the spacer 611 while changing the thickness thereof according to the gap a, it is possible to reliably adjust the gap b to a distance smaller than the gap a. However, as long as the thickness of the spacer 611 can be determined, the measurement method is not limited to the above.

[0026] 3, the inclination of first stopper 610 can be adjusted by providing three or more pairs of first fixing member 612 and spacer 611 and changing the thickness of each spacer 611. This makes it possible to form a uniform gap b around the entire circumference of first stopper 610, which can be made smaller than gap a at any phase.

[0027] Here, the behavior of the periphery of the encoder when tilt axis 130 is tilted by an impact will be described with reference to FIG. 4B.

[0028] In the case of the imaging device 100, harm such as an impact to the camera unit 110 may be inflicted on it to disrupt image capture. When an impact is applied to the camera unit 110, the impact is also transmitted to the tilt axis 130 that holds the camera unit 110. To explain the mechanism related to the tilt axis, a minute gap (not shown) exists between the bearing 210 and the tilt axis 130 to allow the tilt axis to be inserted into the bearing 210. Therefore, as shown in FIG. 4B , an impact may cause the tilt axis 130 to tilt within the gap, starting from the end of the inner periphery of the bearing 210. When tilted, the tilt axis 130 may collide with the bearing 210, deforming the bearing 210 and potentially further increasing the tilt of the tilt axis 130. Furthermore, the tilt axis 130 itself may deform and tilt like a doubly supported beam, starting from the end of the inner periphery of the bearing 210. In either case, when the tilt axis 130 tilts, the encoder scale 510 fixed to the tilt axis 130 also tilts. Since the gap a is formed to be a minute distance of 1 mm or less, if the encoder scale 510 tilts, it may collide with the encoder sensor 411, possibly damaging the encoder sensor 411 or the encoder scale 510.

[0029] In this embodiment, as described above, the first stopper 610 is arranged to be movable in a direction approaching the tilt axis 130 so that the gap a is larger than the gap b. This causes the first stopper 610 to collide with the second stopper 141 before the encoder scale 510 collides with the encoder sensor 411, as shown in FIG. 4B . By forming the second stopper 141 on the pan base 140 made of a highly rigid material, it is possible to minimize deformation of the second stopper 141 when it receives the first stopper 610. Therefore, the tilt axis 130 is prevented from tilting to an angle at which the encoder scale 510 collides with the encoder sensor 411.

[0030] The amount of movement of each component in the tilt axis direction will be described. When the tilt axis 130 tilts, the amount of movement of the first stopper 610 in the direction approaching the second stopper 141 increases as it moves from the central axis toward the outer periphery. In this embodiment, the second stopper 141 is formed closer to the outer periphery than the sensor substrate 410 and the encoder scale 510. When the tilt axis 130 tilts, even with the same angle of tilt, the amount of movement of the first stopper 610 is greater than the amount of movement of the encoder scale 510. Therefore, the first stopper 610 is likely to collide with the second stopper 141 before the encoder sensor 411 and the encoder scale 510. After being released from the impact, the tilt axis 130 returns to its original position, allowing the encoder sensor 411 to continue detecting the rotation angle of the camera unit 110 while maintaining the gap a.

[0031] With the above configuration, according to the first embodiment of the present invention, when an impact is applied to the tilt axis 130, it is possible to maintain angle detection performance by avoiding collision of the encoder scale 510 with the encoder sensor 411 due to displacement or deformation of the tilt axis 130.

[0032] [Embodiment 2] A second embodiment of the present invention will be described below with reference to FIGS. 5 to 6C. In the following, the present embodiment differs from the imaging device according to the above-described embodiment 1 in the mounting configuration of the sensor substrate 410. The following mainly describes the differences from embodiment 1 of the present invention, focusing on the configuration around the encoder. FIG. 5 is an exploded perspective view of the periphery of the encoder in the imaging device of the second embodiment. FIG. 6A is a detailed cross-sectional view of the periphery of the encoder in the imaging device of the second embodiment when the tilt axis is not tilted. FIG. 6B is a detailed cross-sectional view (part 1) of the periphery of the encoder when the tilt axis is tilted due to an external impact or the like in the imaging device of the second embodiment. FIG. 6C is a detailed cross-sectional view (part 2) of the periphery of the encoder when the tilt axis is tilted due to an external impact or the like in the imaging device of the second embodiment.

[0033] In this embodiment, as shown in the perspective view of FIG. 5 and the cross-sectional view of FIG. 6A, sensor substrate 410 is fixed to second stopper 710, which is independent of pan base 140, by screws or the like. Second fixing member 730 presses lug 712 formed on one end of second stopper 710, and lug 712 of second stopper 710 presses elastic member 720, thereby fixing second stopper 710 to pan base 140. At this time, support post 143, which is fixed to pan base 140 by press-fitting or the like, penetrates lug 712 of second stopper 710 and elastic member 720. Second fixing member 730 is fixed to support post 143 by set screw 731, thereby preventing second fixing member 730 from loosening due to vibration or the like. Furthermore, a retraction space 740 (space) is formed between the pan base 140 and the surface of the sensor substrate 410 opposite to the surface on which the encoder sensor 411 is installed.

[0034] The encoder scale 510 is fixed to the tilt shaft 130 at a position facing the encoder sensor 411. At this time, it is preferable to position the sensor substrate 410 relative to the encoder scale 510 so that the gap a is an appropriate distance that is uniform and has little angle error. Therefore, in this embodiment, the gap a can be finely adjusted.

[0035] A method for adjusting the gap a will be described below. One end of the second stopper 710 is constantly biased against the second fixing member 730 by the elastic member 720. A female thread is formed in the second fixing member 730, and a male thread is formed in the support 143. Therefore, by changing the amount of fastening of the second fixing member 730 to the support 143 and thereby changing the amount of pressure applied by the elastic member 720, the second stopper 710 can be moved in the axial direction of the tilt shaft 130. At this time, the sensor substrate 410 is fixed to the second stopper 710, and therefore moves together with the second stopper 710. Therefore, by changing the amount of fastening of the second fixing member 730, the gap a can be finely adjusted. However, it is also possible to finely adjust the gap a by removing the female thread of the second fixing member 730 and the male thread of the support 143 and sliding the second fixing member 730 relative to the support 143. Since second stopper 710 has cutout 711, gap a can be measured using a gap sensor or the like. By changing the amount of tightening of second fixing member 730 while measuring, gap a can be finely adjusted to the desired distance.

[0036] Furthermore, in order to detect the rotation angle with the same accuracy in any phase, it is necessary to maintain the gap a uniform around the entire circumference of the encoder scale 510. Three or more pairs of second fixing members 730 and elastic members 720 are arranged with respect to the second stopper 710. This makes it possible to adjust the inclination of the encoder sensor 411 with respect to the encoder scale 510 by changing the amount of tightening of the second fixing members 730 at each arrangement location. Therefore, it is possible to adjust the gap a uniformly around the entire circumference of the encoder scale 510, making it possible to detect the rotation angle with the same accuracy in any phase.

[0037] Here, first stopper 610 is fixed to tilt axis 130 at a position opposite second stopper 710. In this case, by changing the thickness of spacer 611 in the same manner as in the first embodiment, gap b can be formed so that gap a is larger around the entire circumference of first stopper 610.

[0038] Here, we will explain the behavior of the area around the encoder when tilt axis 130 is tilted by an impact. FIG. 6A shows a state when tilt axis 130 is not tilted. When an external impact is applied to tilt axis 130, first stopper 610 tilts together with tilt axis 130 and collides with second stopper 710, as shown in FIG. 6B. Because support post 143 penetrates lug 712 of second stopper 710 and elastic member 720, as shown in FIG. 6C, the impact causes second stopper 710 to move axially around support post 143 as an axis. At this time, second stopper 710 moves in a direction that presses elastic member 720, and the impact propagated to the second stopper is absorbed by elastic member 720. In other words, lug 712 of second stopper 710 retracts toward pan base 140.

[0039] The sensor substrate 410 is fixed to the second stopper 710 and therefore moves together with the second stopper 710. The direction in which the second stopper 710 presses the elastic member 720 is the same as the direction in which the encoder sensor 411 retreats from the encoder scale 510. This makes it possible to reliably avoid collision between the encoder sensor 411 and the encoder scale 510.

[0040] The impact transmitted to the second stopper is absorbed by the elastic member 720, and the impact on the pan base 140 and the support column 143 is alleviated. As a result, the second fixing member 730 is fixed to the support column 143 and its position is maintained. Therefore, after the impact is released, the second stopper 710 holding the encoder sensor 411 can return to the state shown in FIG. 6A in which it is urged against the second fixing member 730 by the reaction force of the elastic member 720. Therefore, it is possible to maintain the positional relationship between the encoder scale 510 and the encoder sensor 411 at the set gap a except for the moment when the impact is applied. In this embodiment, the support column 143 is formed as a separate part from the pan base 140, but it may also be formed as an integrated part.

[0041] With the above configuration, according to the second embodiment of the present invention, it is possible to avoid collision of encoder scale 510 with encoder sensor 411 when an impact is applied to tilt axis 130, thereby maintaining angle detection performance. Furthermore, it is possible to finely adjust gap a between encoder sensor 411 and encoder scale 510 to an appropriate distance uniformly across all phases, making it possible to detect rotation angles with high precision.

[0042] Other Embodiments While the magnetic encoder has been described as an example in both the first and second embodiments, it is also possible to apply this to other angle detection methods, such as an optical encoder. While the tilt axis 130 has been described as an example, it is also possible to apply this to any axis, such as the pan axis. While the tilt axis 130 is tilted as an example, this is also effective when the tilt axis 130 moves in the axial direction due to an impact (when a misalignment occurs), because the first stopper 610 collides with the second stopper 141 before the encoder sensor 411 and the encoder scale 510.

[0043] (Configuration 1) A camera unit; a rotation shaft supporting the camera unit; a base that holds the rotation shaft in a rotatable state; a sensor substrate disposed on the base; an encoder sensor disposed on the sensor board; an encoder scale held on the rotary shaft at a position facing the encoder sensor; a first stopper held by the rotation shaft at a position facing the base, The imaging device, wherein the distance between the encoder sensor and the encoder scale is greater than the distance between the first stopper and the base.

[0044] (Configuration 2) a rib-shaped second stopper is formed on the base at a position opposite to the first stopper; 2. The imaging device according to configuration 1, wherein the distance between the encoder sensor and the encoder scale is greater than the distance between the first stopper and the second stopper.

[0045] (Configuration 3) 3. The imaging device according to claim 1, wherein the second stopper is located on the outer circumferential side of the rotation axis relative to the encoder sensor.

[0046] (Configuration 4) 4. The imaging device according to any one of configurations 1 to 3, wherein the first stopper is fixed to the rotation shaft in a state where the first stopper is movable in a direction approaching the rotation shaft.

[0047] (Configuration 5) 5. The imaging device according to any one of configurations 1 to 4, wherein one or more spacers are disposed between the first stopper and a surface of the rotation shaft that contacts the first stopper.

[0048] (Configuration 6) A camera unit; a rotation shaft supporting the camera unit; a base that holds the rotation shaft in a rotatable state; a sensor substrate disposed on the base; an encoder sensor disposed on the sensor board; an encoder scale held on the rotary shaft at a position facing the encoder sensor; a first stopper held by the rotation shaft; a second stopper held by the base at a position opposite to the first stopper, An imaging device, wherein the distance between the encoder sensor and the encoder scale is greater than the distance between the first stopper and the second stopper.

[0049] (Configuration 7) 7. The imaging device according to configuration 6, wherein the second stopper is located on the outer circumferential side of the rotation axis relative to the encoder sensor.

[0050] (Configuration 8) 8. The imaging device according to claim 6, wherein the first stopper is fixed to the rotation shaft in a state where the first stopper is movable in a direction approaching the rotation shaft.

[0051] (Configuration 9) The imaging device according to any one of Structures 6 to 8, wherein one or more spacers are disposed between the first stopper and a surface of the rotation shaft that contacts the first stopper.

[0052] (Configuration 10) The imaging device according to any one of Structures 6 to 9, wherein a space exists between the base and a surface of the sensor board opposite to a surface on which the encoder sensor is arranged.

[0053] (Configuration 11) The imaging device according to any one of Structures 6 to 10, wherein the sensor substrate is fixed to the second stopper.

[0054] (Configuration 12) 12. The imaging device according to any one of configurations 6 to 11, wherein the second stopper is fixed to the base in a state where it can move in the direction of the rotation axis.

[0055] (Configuration 13) The imaging device according to any one of Structures 6 to 12, wherein the second stopper is fixed to the base with one or more elastic members disposed between the second stopper and the base.

[0056] (Configuration 14) The imaging device according to any one of Structures 6 to 13, wherein when the first stopper collides with the second stopper, a part of the second stopper presses the elastic member and the sensor substrate moves into the evacuation space. [Explanation of symbols]

[0057] 100...imaging device 110...Camera unit 130...Tilt axis 140...Bread base 141, 710...Second stopper 411...Encoder sensor 510...Encoder scale 610...First stopper 611...Spacer 720...Elastic member 730...Second fixing member 731...Set screw

Claims

1. A camera unit; a rotation shaft supporting the camera unit; a base that holds the rotation shaft in a rotatable state; a sensor substrate disposed on the base; an encoder sensor disposed on the sensor board; an encoder scale held on the rotary shaft at a position facing the encoder sensor; a first stopper held by the rotation shaft at a position facing the base, An imaging device, wherein a distance between the encoder sensor and the encoder scale is greater than a distance between the first stopper and the base.

2. a rib-shaped second stopper is formed on the base at a position opposite to the first stopper; 2. The imaging device according to claim 1, wherein the distance between the encoder sensor and the encoder scale is greater than the distance between the first stopper and the second stopper.

3. 3. The imaging device according to claim 2, wherein the second stopper is located on the outer circumferential side of the rotation shaft relative to the encoder sensor.

4. 2. The imaging device according to claim 1, wherein the first stopper is fixed to the rotation shaft in a state in which the first stopper is movable in a direction approaching the rotation shaft.

5. 5. The imaging device according to claim 4, wherein one or more spacers are disposed between the first stopper and the surface of the rotation shaft that contacts the first stopper.

6. A camera unit; a rotation shaft supporting the camera unit; a base that holds the rotation shaft in a rotatable state; a sensor substrate disposed on the base; an encoder sensor disposed on the sensor board; an encoder scale held on the rotary shaft at a position facing the encoder sensor; a first stopper held by the rotation shaft; a second stopper held by the base at a position opposite to the first stopper, An imaging device, wherein a distance between the encoder sensor and the encoder scale is greater than a distance between the first stopper and the second stopper.

7. 7. The imaging device according to claim 6, wherein the second stopper is positioned on the outer circumferential side of the rotation shaft relative to the encoder sensor.

8. 8. The imaging device according to claim 7, wherein the first stopper is fixed to the rotation shaft in a state where the first stopper is movable in a direction approaching the rotation shaft.

9. 9. The imaging device according to claim 8, wherein one or more spacers are disposed between the first stopper and a surface of the rotation shaft that contacts the first stopper.

10. 8. The imaging device according to claim 7, wherein a space exists between the base and a surface of the sensor board opposite to the surface on which the encoder sensor is arranged.

11. 11. The imaging device according to claim 10, wherein the sensor substrate is fixed to the second stopper.

12. 12. The imaging device according to claim 11, wherein the second stopper is fixed to the base in a state where it can move in the direction of the rotation axis.

13. 13. The imaging device according to claim 12, wherein the second stopper is fixed to the base with one or more elastic members disposed between the second stopper and the base.

14. 14. The imaging device according to claim 13, wherein when the first stopper collides with the second stopper, a part of the second stopper presses the elastic member and the sensor substrate moves into the space.

Images