JP2002158575A - Attaching device for photoelectric switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an attaching device for photoelectric switch, capable of easily controlling the optical axis, even while the beam of light emitted from the flood means of a flood lamp or field of view of a light-receiving means in a light receiver is set narrow. SOLUTION: An end face member 34 is fixed on the end face of a flood lamp 22, and a semi-columnar part 35, with an emission plane 30 almost as a central axis, is formed on this end face member 34. An engage part 40 is formed on an attaching member 37 as the main body of an attaching device 32, and that engage part 40 is mounted on the semi-columnar part 35. Therefore, since the axis of turning from the attaching device 43 to the flood lamp 22 becomes almost the same plane as the emission plane 30, when the flood lamp 22 is turned for controlling the optical axis, the emission plane 30 is turned at that position. Thus, fine optical axis control can e performed easily.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoelectric switch mounting device for supporting a light emitting device having a light emitting means and a light receiving device having a light receiving means so as to be rotatable around a rotation axis in a state where they are opposed to each other. About.

[0002]

2. Description of the Related Art In a so-called transmission type photoelectric switch, light emitted from a light projecting means of a light projector enters a light receiving means of a photodetector arranged oppositely, and light incident on the light receiving means is reliably received by the light receiving means. It is necessary to adjust the optical axis so that the light projector and the light receiver are supported by a mounting device capable of adjusting the optical axis. That is, in the light projector, the optical axis is adjusted by changing the direction of the light emitted from the light projecting means so that the emitted light irradiates the light receiver arranged opposite to the light receiver. In the light receiver, the optical axis is adjusted by changing the direction of the field of view of the light receiving means so as to efficiently receive the light emitted from the light emitter.

As a mounting device for adjusting the optical axis of a light projector or a light receiver in a photoelectric switch, there is one disclosed in Japanese Patent Application Laid-Open No. H11-329180, for example, as shown in FIG. This is because the annular rib 1 attached to the end of the light emitter or the light receiver is formed by using members 2 and 3 and screws 4 and 5 formed to match the shape of the rib 1 and the outer peripheral surface of the rib 1. , And the projector or the light receiver is rotatably supported.

Further, as shown in FIG.
There is one disclosed in Japanese Patent No. 4433. This is an L-shaped member that is attached to the mounting end of the light emitter or the light receiver so as to sandwich the U-shaped member 6 and that the U-shaped member 6 is formed with concentric guide holes 7a to 7d. By mounting 8 with screws 9a and 9b, the light projector or the light receiver is rotatably held.
Further, as disclosed in Japanese Utility Model Publication No. 2554755, an end piece is attached to an opening of a main body case of a light emitter or a light receiver, and an L-shaped member provided with a guide hole in the end piece is attached. That can be rotatably held.

[0005]

However, such a conventional configuration has the following problems. In any of the above-mentioned inventions (deviations) shown as conventional examples, as shown in FIG. 12, a substantially center position (indicated by A in the figure) of the end portions of the light emitter 10 and the light receiver 11 becomes the center of rotation. Supported by the mounting device. For this reason, since the center of rotation and the emission surface of the light projecting means are far apart in the light projector, when the light projector is rotated to adjust the optical axis, the light emitted from the light projecting means is rotated with the rotation of the light projector. The surface moves in the rotating direction at the same time as the surface is rotated, and the optical axis is moved by that much.

In this case, as shown in FIG. 13A, when the beam of light emitted from the light projector 10 (indicated by B in the figure) is set to be wide, a dotted line or a two-dot chain line in the figure is used. Even if the projector 10 is rotated to the position shown in FIG.
Of the light emitter 1
The larger the beam of light emitted from zero, the smaller the amount of light received by the light receiver 11, so that it is more susceptible to disturbance light and the detection accuracy is reduced.

Therefore, it is generally desirable that the beam of light from the projector 10 be narrow, but the beam of light emitted from the projector 10 (indicated by C in the figure) is set to be narrow as shown in FIG. When the light projector 10 is rotated by the same angle as that of FIG. 13A, light emitted from the light projector 10 does not enter the light receiver 11 as shown by a dotted line or a two-dot chain line in the figure. Therefore, it is difficult to adjust the optical axis.

Similarly, since the light receiving device 11 is away from the center of rotation to the incident surface of the light receiving means, the light receiving device 1
When the lens 1 is rotated to adjust the optical axis, the incident surface of the light receiving means moves in the rotating direction with the rotation, and it is difficult to adjust the optical axis. In particular, when the field of view of the light receiver 11 is set to be narrow to prevent the influence of disturbance light, it becomes more difficult to adjust the optical axis.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a structure in which a projector and a light receiver are supported so as to be rotatable around a rotation axis in a state where they face each other. It is an object of the present invention to provide a photoelectric switch mounting device capable of easily adjusting an optical axis even when a beam of light emitted from an optical unit or a field of view of a light receiving unit of a light receiver is set to be narrow. .

[0010]

In order to achieve the above object, the invention according to claim 1 is directed to a rotating shaft in which a light emitting device having light emitting means and a light receiving device having light receiving means are opposed to each other. In a photoelectric switch mounting device rotatably supported as a center, the rotation axis is provided at a position substantially flush with an emission surface of the light emitting means and an incidence surface of the light receiving means. Has features.

According to such a configuration, the rotation axis of the mounting device for rotatably supporting the light emitter and the light receiver is located at a position substantially flush with the emission surface of the light emitting means and the incidence surface of the light receiving means. When the light projector is turned, the light is turned around the light emitting surface of the light projecting means. As a result, the emission surface of the light emitting means rotates at that position, and the emission surface does not move in the rotation direction. Similarly, even if the light receiver is rotated to adjust the optical axis, the incident surface of the light receiving means is rotated at that position, and the incident surface does not move in the rotational direction. Therefore, even if the light beam emitted from the light projecting means is narrowed or the field of view of the light receiving means is narrowed so as not to lower the detection accuracy of the photoelectric switch, the optical axis adjustment of the light projector and the light receiver can be performed. It can be done easily.

According to a second aspect of the present invention, in a state where the light emitter having a plurality of light emitting means and the light receiver having a plurality of light receiving means face each other, the light emitter is supported so as to be rotatable around a rotation axis. In the photoelectric switch mounting device described above, the rotating shaft is characterized in that it is provided at substantially the same position as each emission surface of the plurality of light emitting means and each incidence surface of the plurality of light receiving means. .

According to such a configuration, the rotation axis of the mounting device is provided at a position substantially flush with each of the emission surfaces of the plurality of light projecting means and the respective incidence surfaces of the plurality of light receiving means. When the light projector is turned, the light is turned about each of the light emitting surfaces of the plurality of light emitting means, and when the light receiver is turned, the light is turned about each of the light incident surfaces of the plurality of light receiving means. It will rotate. Thereby, in a photoelectric switch having a plurality of light projecting means and light receiving means, when the light beam emitted from the light projector is narrowed so as not to lower the detection accuracy of the photoelectric switch, or the field of view of the light receiver is narrowed. Even in this case, the optical axis can be easily adjusted.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment in which the present invention is applied to a multi-optical axis photoelectric switch will be described below with reference to FIGS.

FIG. 2 shows how the photoelectric switch is used. In FIG. 2, the projector 2 of the photoelectric switch 21
2 and the light receiver 23 are opposed to each other so as to sandwich each opening of the component storage shelf. When light emitted from the light emitter 22 toward the light receiver 23 is blocked, the light receiver 2
3 outputs a detection signal. In this case, the detection signal from the photoelectric switch 21 is provided to a higher-order programmable controller (not shown), and the programmable controller determines whether the detection signal is output from a predetermined photoelectric switch 21 or not. It is determined whether or not the worker has correctly taken out the parts stored in the parts storage shelf.

FIG. 3 schematically shows a cross section of the light projector 22. In FIG. 3, a rectangular cylindrical element block 25 made of plastic is inserted in a rectangular cylindrical metal main body case 24. A light projection board 26a and a drive board 26b are supported in the element block 25, and the boards 26a and 26b are electrically connected by a cable (not shown).

A plurality of light emitting elements 27 are arranged at a predetermined pitch on the light emitting substrate 26a. A drive circuit (not shown) is mounted on the drive board 26b.
A driving current is output at a predetermined timing to the light projecting element 27 installed in the light emitting element 6a. In this case, the drive circuit is configured to execute a scan operation for sequentially emitting light from each light emitting element 27 by sequentially applying a drive current to each light emitting element 27.

A window 28 is formed on the front surface of the main body case 24 and the element block 25, and a lens block 29 is fixed to the window 28. The lens block 29 has a plurality of convex lens portions 29a formed at a predetermined pitch. When the lens block 29 is mounted on the window portion 28, each convex lens portion 29a is positioned on the optical axis of each light projecting element 27. are doing. In this case, the front surface of the lens block 29 is the light emission surface 30.

With the above configuration, the light emitted from the light projecting element 27 is converted into substantially parallel light by the convex lens portion 29a of the lens block 29 and emitted from the emission surface 30 toward the light receiver 23.

The light receiver 23 has substantially the same structure as the light projector 22. The light emitted from the light projector 27 is condensed by the light receiving lens of the lens block and the light receiving element (neither is shown). ) To receive light.
In this case, the front surface of the lens block of the light receiver 23 is the incident surface 31 (see FIG. 2).

Here, the light projector 22 and the light receiver 23 having the above-mentioned structure are supported by the mounting device 32 at their upper and lower portions at predetermined positions on the wall surface 33 of the component storage shelf so as to be capable of adjusting the optical axis in an opposed state. Has become.

FIG. 1A is an exploded perspective view of a mounting device 32 that supports the light projector 22 so that the optical axis can be adjusted. In FIG. 1A, the end opening of the main body case 24 of the light projector 22 is closed by an end member 34. A semi-cylindrical portion 35 is formed on the end surface member 34, and the central axis of the semi-cylindrical portion 35 is located substantially flush with the front surface of the main body case 24, that is, the emission surface 30. The semi-cylindrical portion 35 has insertion holes 36a and 36b substantially perpendicular to the front surface of the main body case 24.

The mounting device 32 includes a metal mounting member 37.
, Screws 38a and 38b, and nuts 39a and 39b. The mounting member 37 includes an engaging portion 40 slidably formed in contact with the arc surface 35a of the semi-cylindrical portion 35 of the end surface member 34, first wall mounting portions 41a and 41b, and a second wall mounting portion 41a. It is formed integrally with the wall mounting portions 42a and 42b. In this case, the back side of the light projector 22 is attached to the first wall mounting portions 41a and 41b.
3 are formed, respectively, and insertion holes 43a and 43b for mounting the second wall mounting portion 42 are provided.
The wall holes a and b are formed with wall mounting slots 44a and 44b for mounting the side surface of the light projector 22 so as to face the wall surface 33, respectively. An arc-shaped long hole 45 is formed along the engaging portion 40.

FIG. 1B shows an assembled state of the mounting device 32. In FIG. 1B, the screws 38a, 38
8b is inserted through the insertion holes 36a and 36b and the arc-shaped long hole 45 of the engagement portion 40 in order and screwed to the nuts 39a and 39b, whereby the mounting device 32 is mounted on the end face member 34.

In the form in which the mounting device 32 is mounted on the light projector 22 in this manner, the engaging portion 40 of the mounting member 37 is slidable with respect to the arc surface 35a of the end member 34 of the light projector 22. The mounting position of the mounting device 32 with respect to the end face member 34 can be changed along an arcuate surface 35a having an arc shape having the emission surface 30 substantially at the center. That is, the light projector 22 is supported by the mounting device 32 so as to be rotatable about the emission surface 30. Similarly, the light receiver 23 is supported by the mounting device 32 so as to be rotatable about the incident surface 31.

Next, the operation of the above configuration will be described. The light projector 22 and the light receiver 23 are mounted on the wall surface 33 of the component storage shelf by the mounting device 32. In this case, as shown in FIG. 2, the first wall-mounting portion 41 of the mounting member 37 of the mounting device 32 is used to face the inside of the opening of the wall surface 33.
It is fixed to the wall surface 33 by bolts (not shown) through the insertion holes 43a and 43b formed in the a and 41b. When the light emitter 22 and the light receiver 23 are mounted on the front surface of the wall surface 33, the light transmitter 22 and the light receiver 23 are fixed to the wall surface 33 by bolts (not shown) through the wall mounting slots 44a, 44b formed in the second wall mounting portions 42a, 42b. .

When the mounting of the light projector 22 and the light receiver 23 by the mounting device 32 is completed, the optical axes of the light projector 22 and the light receiver 23 are adjusted.

FIGS. 4 (a) and 4 (b) show the principle representing the light emitting direction when the projector 22 is turned around the emitting surface 30 to adjust the optical axis of the projector 22. FIG. FIG.
FIG. 4A shows a case where the beam of light emitted from the light projector 22 is adjusted widely, and FIG.
The case where the beam of light emitted from is adjusted to be narrow.

When the projector 22 rotates to adjust the optical axis, the projector 22 rotates about the light exit surface 30 as described above, and the moving range of the optical axis at that time is as follows.
The size is smaller than that of the conventional example shown in the description of FIGS. That is, since the light projector 22 rotates around the light exit surface 30 at the time of optical axis adjustment, if the light projector 22 rotates to adjust the light axis, the light exit surface 30 will rotate at that position. That is, the emission surface 30 does not move in the rotation direction. Therefore, when the optical axis of the light projector 22 is adjusted, the light emitting direction of the light emitting element 27 can be slightly changed, so that the light beam from the light projector 22 is set to be narrow as shown in FIG. Even if you do
The light can be easily incident on the incident surface 31 of the light receiver 23.

Similarly, since the center of rotation of the light receiver 23 when adjusting the optical axis is set on the incident surface 31, if the light receiver 23 is rotated to adjust the optical axis, the incident surface 31 is It turns at that position and the incident surface 31 does not move in the turning direction. Therefore, even when the field of view of the light receiver 23 is set to be narrow, when the optical axis of the light receiver 23 is adjusted, the direction of the field of view of the light receiver 23 is minutely changed so that the light from the light projector 22 is surely emitted. Light can be received.

According to the first embodiment, the mounting device 32 is provided at a position where the rotation axis for rotatably supporting the light projector 22 is substantially flush with the emission surface 30. Unlike the conventional example in which the center of rotation is provided substantially at the center of the end face of the projector, the swing of the optical axis when the projector 22 is rotated to adjust the optical axis is reduced, and the subtle optical axis Adjustment can be easily performed. Similarly, the receiver 2
The swing of the optical axis when rotating for adjusting the optical axis of the optical axis 3 is reduced, and the optical axis of light received by the light receiver 23 can be easily adjusted. That is, the optical axis can be easily adjusted even when the beam of light emitted from the light projector 22 or the field of view of the light receiver 23 is narrowed so as not to lower the detection accuracy of the photoelectric switch 21.

FIG. 5 shows a modification of the mounting device 32 described above. Attachment member 4 which is the main body of attachment device 32
Reference numeral 6 denotes an engagement portion 40 formed so as to be slidable while being in contact with the arc surface 35a of the end member 34 of the light projector 22;
Wall mounting portion 47, and second wall mounting portions 48a, 48b
Are formed in an integrated shape. The first wall mounting portion 47 has a wall mounting hole 49 formed in a U-shape. The second wall mounting portions 48a and 48b are formed with L-shaped wall mounting holes 50a and 50b, respectively. Other parts are the same as those of the attachment member 37 in FIG. 1, and the description thereof is omitted.

The mounting member 46 is provided with the first wall mounting portion 4.
When 7 is mounted on the wall surface 33, the rear surfaces of the light projector 22 and the light receiver 23 are mounted, and the light projector 22 and the light receiver 23 can be easily moved and adjusted in the horizontal direction. When one of the second wall mounting portions 48a and 48b is mounted on the wall surface 33, the light emitting device 22 and the light receiving device 2
3, the optical axes of the light projector 22 and the light receiver 23 can be easily adjusted in the vertical direction and the front-back direction.

(Second Embodiment) FIG. 6 shows a second embodiment of the present invention. Each of FIGS. 1 (a) and 1 (b) in the first embodiment will be described. FIG. 4 is a corresponding perspective view, in which the same parts as those in the first embodiment are denoted by the same reference numerals, and different parts will be described below.

The mounting device 51 includes a metal mounting member 37.
, Screws 38a and 38b, nuts 39a and 39b, and a spacer member 52. Mounting member 37
Is configured such that screws 38a, 38b are screwed to nuts 39a, 39b via a spacer member 52, respectively. Here, the front surface of the spacer member 52 is
It is formed in a curved shape slidable with respect to 0, and its rear surface is formed in a planar shape so that the nuts 39a and 39b are in close contact with each other. In the spacer member 52, insertion holes 53a, 53b having substantially the same diameter as the insertion holes 36a, 36b provided at the end of the light projector 22 are formed, and the screws 38a, 38b are connected to the arc-shaped long holes of the engagement portion 40. 45 and the insertion holes 53a and 53b of the spacer member 52 are inserted in this order and screwed to the nuts 39a and 39b, respectively.

According to the second embodiment, since the nuts 39a and 39b are screwed to the screws 38a and 38b in a state of being in close contact with the spacer member 52, compared with the first embodiment. Thus, the support state of the mounting device 51 with respect to the light projector 22 and the light receiver 23 can be stabilized.

(Third Embodiment) FIG. 7 shows a third embodiment of the present invention, in which the end of the light projector 22 and the mounting device 61 are shown in a perspective view. In this FIG.
An end member 62 is fixed to an end surface of the main body case 24 in the light projector 22, and a screw hole 63 is formed in the center of the end portion of the end surface member 62 located on the front side of the main body case 24.
Are formed. That is, the screw hole 63 is
Is formed at a position that is substantially flush with the exit surface 30. In addition, a shaft 64 is erected on the end face member 62 at a predetermined distance from the screw hole 63.

On the other hand, the mounting member 65 has an L-shape, and has wall mounting holes 66a and 66b. A bearing hole 67 is formed at an end of the mounting member 65, and a screw 68 is inserted through the bearing hole 67 into the screw hole 6.
3 is screwed. The end face member 62 has a bearing hole 67.
A curved insertion hole 69 is formed at a position concentric with the center as a center, and the shaft 6 of the end face member 62 is
4 is to enter.

With the above configuration, the projector 22 is supported by the mounting device 61 so as to be rotatable about the emission surface 30.

According to the third embodiment, when the projector 22 is turned to adjust the optical axis,
Since the rotation is made about the emission surface 30 as a center, the deflection of the optical axis becomes smaller and the optical axis becomes smaller, as in the first embodiment, as compared with the conventional example which rotates at the substantially center position of the end face of the light projector. Adjustment can be easily performed. Similarly, a light receiver 2 (not shown)
Also in the case of 3, the optical axis can be adjusted easily because it rotates about the incident surface 31 substantially at the time of optical axis adjustment. Therefore, even if the beam of light emitted from the light projector 22 or the field of view of the light receiver 23 is narrowed so that the detection accuracy of the photoelectric switch 21 is not reduced, the optical axis can be easily adjusted.

Further, the structure is simpler than that of the first and second embodiments, so that the cost can be reduced.

As shown in FIG. 8, a shaft 73 is erected on a mounting member 72 and a curved groove 76 is formed in an end surface member 74 at a position concentric with the screw hole 63 as a center. , The shaft 73 may enter the groove 76.

(Fourth Embodiment) FIG. 9 shows a fourth embodiment of the present invention, in which the end of the light projector 22 and the mounting device 81 are shown in perspective. 9, an end face member 82 is fixed to an end face of the main body case 24 of the light projector 22, and a screw hole 83 is provided at a predetermined position of the end face member 82.
a, 83b are formed. In this case, these screw holes 83a and 83b are formed on concentric circles with the emission surface 30 substantially at the center. On the other hand, the mounting member 84 has an L-shape, and a curved guide hole 85 is formed on a concentric circle with the emission surface 30 substantially at the center. Also, the mounting member 84
Are formed with wall mounting holes 86a and 86b.

Then, the screws 87a and 87b are attached to the mounting member 8.
4 is screwed into the screw holes 83a and 83b formed in the end face member 82 via the guide holes 85 of
Can be rotatably supported by the mounting device 81.

According to the fourth embodiment, when the projector 22 is turned to adjust the optical axis,
Since the light is rotated about the light exit surface 30 substantially, the light exit surface 30
Is rotated at that position, and the emission surface 30 does not move in the rotation direction. Therefore, similarly to the first embodiment, a beam of light emitted from the light projector 22 so that the detection accuracy of the photoelectric switch 21 is not reduced.
Alternatively, even when the field of view of the light receiver 23 is narrowed, the optical axis adjustment can be easily performed.

(Other Embodiments) The above embodiment has been described in the case where there are a plurality of light projecting elements and a plurality of light receiving elements. However, only one light emitting element and one light receiving element are provided. A configuration may be used.

[0047]

As described above, according to the photoelectric switch of the present invention, the rotation axis of the mounting device that supports the light projector so that the optical axis can be adjusted is the same as the emission surface of the light projection means and the incidence surface of the light reception means. Since the light emitting device and the light receiving device are rotated to adjust the optical axis, the light emitting surface and the light receiving surface of the light receiving device are rotated at the position. Become. Therefore, since the exit surface and the entrance surface do not move in the rotation direction, the optical axis can be easily adjusted even when the beam of light from the projector or the field of view of the light receiver is set to be narrow. This has the effect that it can be performed.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view and an assembled view showing a main part according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of use of a multi-optical axis photoelectric switch;

FIG. 3 is a cross-sectional view of the projector.

FIG. 4 is a principle diagram showing an emission direction of light from a projector to a receiver.

FIG. 5 is a diagram showing a modification of the mounting member according to the first embodiment.

FIG. 6 is a view corresponding to FIG. 1, showing a second embodiment of the present invention;

FIG. 7 is a view corresponding to FIG. 1A showing a third embodiment of the present invention.

FIG. 8 is a view corresponding to FIG. 1A showing a modification of the mounting member according to the third embodiment.

FIG. 9 is a view corresponding to FIG. 1A showing a fourth embodiment of the present invention.

FIG. 10 shows a conventional example and is equivalent to FIG.

FIG. 11 is a diagram corresponding to FIG. 1A showing another conventional example.

FIG. 12 is a principle diagram showing a rotation state of a cross section of the photoelectric switch.

FIG. 13 is a diagram corresponding to FIG. 4, showing another conventional example.

[Explanation of symbols]

21 is a photoelectric switch, 32, 51, 61, 71 and 81 are mounting devices, 33 is a wall surface, 30 is an emission surface, and 31 is an incident surface.

Claims (2)

[Claims] 1. A photoelectric switch mounting device for supporting a light emitting device having a light projecting means and a light receiving device having a light receiving means so as to be rotatable around a rotation axis in a state facing each other. Is provided at a position substantially flush with an emission surface of the light emitting means and an incidence surface of the light receiving means. 2. A photoelectric switch mounting device for supporting a light projector having a plurality of light emitting means and a light receiver having a plurality of light receiving means so as to be rotatable about a rotation axis in a state where the light projector has a plurality of light receiving means. The photoelectric switch mounting device, wherein the rotation shaft is provided at a position substantially flush with each of the emission surfaces of the plurality of light projecting means and the respective incidence surfaces of the plurality of light receiving means.