JP2007057345A - Tilt sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin tilt sensor loadable on a small-sized portable apparatus or the like, which detects accurately a tilt position, and prevents deterioration caused by using frequency, a secular change or the like. <P>SOLUTION: This tilt sensor 21 has a constitution comprising: a casing 20; a photodetection means comprising a light emitting part 25 and light receiving parts 26a, 26b arranged in the casing 20; and a rotary blade 24 supported rotatably by the casing 20, for covering the light receiving parts 26a, 26b by being rotated to the upside of the light receiving parts 26a, 26b of the photodetection means when the casing 20 is tilted. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an inclination sensor that is mounted on a small device such as a mobile phone or a camera and detects an inclination from a horizontal position.

  In order to detect the vertical and horizontal inclinations of the composition at the time of shooting with a camera and the movement and posture of a toy, a robot, and the like, there are devices that include an inclination sensor inside a device such as a camera. Many conventional tilt sensors use contact-type detection means including a plurality of fixed contacts provided in the tilt direction and a movable contact that contacts one of the fixed contacts when tilted.

An inclination sensor using such a contact-type detection means is, for example, as shown in Patent Document 1, a box-shaped housing having a space inside, and two or four directions in the housing. Are provided with a plurality of fixed contacts and a movable contact made of a small ball that rolls toward the fixed contacts. In this tilt sensor, when the casing is tilted, the tilt is detected by switching when the ball body rolls and contacts a fixed contact in the tilted direction.
JP 11-195359 A

  In the conventional tilt sensor, the ball body, which is a movable contact, detects the tilt by rolling and contacting the fixed contact disposed in the housing, so that dust or the like adheres to the ball body. Or may be deformed by friction or contact with the housing or the fixed contact during long-time use. In this way, if dust adheres to the ball body, deformation or the like occurs, the movement to the fixed contact cannot be performed smoothly, and detection accuracy such as a delay in switching when tilting or returning to the horizontal position occurs. There is a problem of causing a decrease. Further, when the ball body moves, there is a problem that an abnormal noise such as a friction sound with the housing or a collision sound when colliding with the fixed contact is generated.

  Further, since the ball body has a certain thickness and a space for the ball body to roll, the housing size becomes large, and it becomes difficult to mount it on a thin portable device.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a thin tilt sensor that can accurately detect tilt and prevents deterioration due to frequency of use or aging, and can be mounted on a small portable device. .

  In order to solve the above-described problems, the tilt sensor of the present invention includes a light detection unit including a light emitting unit and a light receiving unit, and a rotary blade that covers the light receiving unit of the light detection unit when tilted. Features.

  In addition, the tilt sensor of the present invention includes a casing, a light detection unit including a light emitting unit and a light receiving unit disposed in the casing, and is rotatably supported by the casing, and the light detection is performed when the casing is tilted. A rotating blade that rotates above the light receiving portion of the means and covers the light receiving portion is provided.

  According to the tilt sensor according to the present invention, the fixed contact for detecting the tilted direction is constituted by the light detecting means having the light receiving unit for sensing light, and the movable contact that moves when tilted rotates the light receiving unit. Since it is composed of blades, tilt detection, which is conventionally performed by the contact method, can be performed by a non-contact method using light as a medium. By configuring such non-contact detection with the light receiving unit and the rotating blade covering the light receiving unit, the tilt detection can be performed smoothly without any obstacles, and stable detection accuracy can be maintained over a long period of time. can do.

  Moreover, since the main components for detecting the inclination are the reflection type light detection means including the light emitting part and the light receiving part and the thin plate-like rotary blades covering the light detection means, it is easy to install in the thin casing. This makes it possible to reduce the size and thickness of an electronic device such as a camera that performs tilt detection.

  Embodiments of a tilt sensor according to the present invention will be described below in detail with reference to the accompanying drawings. Here, FIG. 1 is a plan view showing the inside of the tilt sensor when placed in a horizontal position, FIG. 2 is a cross-sectional view taken along line AA of the tilt sensor, and FIG. 3 is a cross-sectional view taken along line BB of the tilt sensor. is there.

  As shown in FIGS. 1 to 3, the tilt sensor 21 of the present invention includes a casing 20 having a space 29 on a substrate 22, a rotating shaft 23 that is rotatably attached to the center of the casing 20, and the rotating shaft. The rotating blade 24 attached to the outer periphery of the light source 23, the light emitting part 25 disposed on the substrate 22, and a pair of light receiving parts 26 a and 26 b that receive light emitted from the light emitting part 25. The substrate 22 is provided with a hole portion 27 for axially supporting the lower end portion of the rotary shaft 23 at the center portion, and a bearing portion 28 for smooth rotation of the rotary shaft 23 in the hole portion 27. The casing 20 includes a frame body 30 that encloses a space 29 having a size that allows the rotating blades 24 to rotate, and a lid body 31 that is placed on the frame body 30. The lid body 31 is provided with a hole portion 32 into which the upper end portion of the rotary shaft 23 can be fitted at the center. The casing 20 is provided to facilitate incorporation into a device such as a mobile phone or a camera for detecting inclination, but the light emitting unit 25, the light receiving units 26a and 26b, the rotary blade 24, etc. If it can be directly mounted on a mother board or the like installed inside the device, it need not be provided.

  As shown in FIG. 2, the rotary shaft 23 includes an axial center 33 that is rotatably supported by holes 27 and 32 provided at the centers of the substrate 22 and the lid 31, and a substantially intermediate position between the axial center 33. And a rotating blade fixing portion 34 projecting over. As shown in FIG. 3, the rotating blade 24 has a ring-shaped fixing portion 35 fixed on the rotating blade fixing portion 34 through the upper end portion of the shaft center portion 33, and a predetermined portion from the outer peripheral portion of the fixing portion 35. The fan-shaped blade portion 36 having a circular arc surface with a width is integrally formed. The blade portion 36 is formed of a fan-shaped resin plate having a central angle opened at approximately 90 degrees, and an anti-reflection measure is applied to the surface facing the substrate 22 side. As this anti-reflection measure, a method of coloring the surface of the blade portion 36 with a black paint or attaching an anti-reflection sheet member is employed.

  In addition, a reflector 37 for reflecting the light emitted from the light emitting unit 25 toward the light receiving units 26a and 26b is disposed above the rotating blade 24. The reflection plate 37 is formed in a disk shape having the rotation radius of the rotary blade 24 in order to cover the entire light emitting unit 25 and the light receiving units 26 a and 26 b mounted on the substrate 22. The reflection plate 37 is disposed on the back side of the lid body 31. Further, without providing such a reflection plate 37, the lid 31 may be formed of a metal plate having a high light reflectance, or a metal film may be deposited on the back surface of the lid 31.

  The pair of light receiving portions 26a and 26b are constituted by light receiving elements such as photodiodes and phototransistors, and are mounted on the substrate 22 with the light receiving surfaces facing upward on both sides of the substrate 22 across the rotating shaft 23. ing. The light receiving portions 26 a and 26 b are disposed within the rotation radius of the rotary blade 24.

  The light emitting unit 25 is configured by a light emitting element such as a light emitting diode, and is disposed within a range in which light can be received on the light receiving units 26a and 26b via the reflection plate 37. At least one light emitting unit 25 is disposed within the rotation radius of the rotary blade 24, similarly to the light receiving units 26a and 26b.

  Also, a control function for driving the light emitting unit 25 and the light receiving units 26a and 26b on the substrate 22 and for converting ON / OFF of light detected by the light receiving units 26a and 26b into electric signals. Etc. are mounted.

  When the tilt sensor 21 shown in FIG. 1 is placed in a horizontal position without tilt, as shown in FIG. 4A, the blade portion 36 of the rotary blade 24 does not reach the light receiving portions 26a and 26c. It is in a stationary state at an intermediate position. When the blade portion 36 is in this position, the light emitted from the light emitting portion 25 is reflected through the reflecting plate 37 disposed above the blade portion 36, so that the light receiving portions 26a and 26b are always on the side. It is in the light receiving (ON) state. When tilted to the left from the state of FIG. 4A, the blade portion 36 rotates to the left to cover the upper part of the light receiving portion 26a (FIG. 4B). Further, when tilted to the right side from the state of FIG. 4A, the blade part 36 rotates to the right side and covers the upper part of the light receiving part 26b (FIG. 4C). Thus, when the blade | wing part 36 has rotated to the position of FIG.4 (b) or FIG.4 (c), the light emitted from the light emission part 25 is interrupted | blocked (OFF). As described above, it is detected that the camera is tilted by switching from ON to OFF, and the tilted direction can be detected depending on which of the light receiving portions 26a and 26b is OFF.

  The tilt sensor 21 of the above embodiment is configured such that the light emitted from the light emitting unit 25 can be constantly detected on the light receiving units 26a and 26b side, and the light receiving units 26a and 26b are shielded by the blade unit 36 when tilted. However, it may be configured to detect the inclination by receiving the light reflected through the rotary blade 24, on the contrary. FIG. 5 shows a schematic configuration example of a tilt sensor 41 configured to detect tilt using reflected light based on the tilt sensor 21. In the inclination sensor 41 of this embodiment, a light reflection action is given to the blade portion 43 of the rotary blade 24, and a reflection type light detection means including a light emitting portion and a light receiving portion is provided in the direction in which the blade portion 43 rotates. . The blade portion 43 is entirely formed of a metal material, or is formed by vapor-depositing a metal film or attaching a thin metal material on a surface facing the light detection means. Photoreflectors 42 a and 42 b in which a light emitting portion and a light receiving portion are integrated are used as the light detection means, and are mounted at predetermined positions within the rotation radius of the blade portion 43. In the tilt sensor 41, in the horizontal state where the blade portion 43 is stationary at a position away from the photo reflectors 42a and 42b, both the photo reflectors 42a and 42b remain OFF, but FIG. ) And (c), when the blade portion 43 is tilted in a direction as shown in FIG. 5C, the blade portion 43 is rotated to a position where one of the photo reflectors 42a and 42b is blocked. And when the said blade | wing part 43 returns to the original horizontal position, it switches from ON to OFF. In this way, the tilt direction can be detected by the reflected light via the blade portion 43. In the tilt sensor 41 of this embodiment, since the blade portion 43 has a reflecting action, unlike the tilt sensor 21, it is not necessary to provide the reflecting plate 37 above the rotary blade 24.

  Since the inclination sensor 21 of the embodiment shown above has a configuration in which a pair of light receiving portions are provided at positions facing each other across the rotation axis, the inclination in one of the front and rear directions or the left and right directions and the confirmation of the inclination direction are performed. However, it is possible to detect the inclination in all directions by providing the light receiving part in both the front and rear and left and right directions. In addition, if the tilt detection is performed only in one direction, it is possible to provide only one light receiving unit in the tilt direction.

  As described above, according to the tilt sensor of the present invention, since it is configured to detect the tilt by the non-contact overlapping state between the light receiving portion and the rotating blade rotating on the light receiving portion, Wear and deterioration in the detection unit are unlikely to occur, and stable detection accuracy can be maintained over a long period of time.

It is a top view of the inclination sensor which concerns on this invention. It is AA sectional drawing of the said inclination sensor. It is BB sectional drawing of the said inclination sensor. It is explanatory drawing which shows the inclination detection operation | movement in the said inclination sensor. It is explanatory drawing of the inclination sensor which detects an inclination direction with reflected light.

Explanation of symbols

DESCRIPTION OF SYMBOLS 20 Casing 21 Inclination sensor 22 Board | substrate 23 Rotating shaft 24 Rotating blade 25 Light emission part 26a, 26b Light receiving part 27 Hole part 28 Bearing part 29 Space part 30 Frame body 31 Cover body 32 Hole part 33 Axial part 34 Rotating blade fixing | fixed part 35 fixation Part 36 Blade part 37 Reflector 38 IC
41 Inclination sensor 42a, 42b Photo reflector 43 Blade

Claims (6)

An inclination sensor comprising: a light detection unit including a light emitting unit and a light reception unit; and a rotary blade that covers an upper portion of the light reception unit of the light detection unit when tilted. A casing, a light detecting means comprising a light emitting part and a light receiving part disposed in the casing, and a casing rotatably supported by the casing, wherein the casing rotates above the light receiving part of the light detecting means when tilted. And a tilt sensor including a rotating blade that covers the light receiving unit. The inclination sensor according to claim 1, wherein a plurality of the light receiving portions are provided and the rotating blade covers at least one of the plurality of light receiving elements when inclined. The inclination sensor according to claim 1, wherein the rotating blade is in a position not covering the light receiving portion when horizontal. The rotating blade is rotatably supported by a rotating shaft provided at a substantially central portion of the casing, and a pair of light receiving portions are disposed within a rotating radius of the rotating blade in both directions across the rotating shaft, and The inclination sensor according to claim 2, wherein the light emitting unit is disposed within an equal distance from the pair of light receiving units. The tilt sensor according to claim 1, wherein the rotary blade is formed in a fan shape, and a main part of the fan shape is rotatably supported.

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