JP2003016891A - Multi-optical axial photoelectric sensor and projector and light receiver included therein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-optical axial photoelectric sensor facilitating the free set of bending angles between adjacent projectors and between adjacent light receivers, while keeping the separating distance between optical axes substantially constant in the formation of a broad optical curtain, by mutually connecting two or more multi-optical axial photoelectric sensors. SOLUTION: The projector 1 has an outer profile, formed by an Al-made case body 2 formed of an extrusion molded product and terminal members 5 formed of a plastic molded product mounted on both ends thereof. The terminal member 5 has a cutout part 9, and the cutout part 9 is extended to the end of the terminal member 5. When a flexible cable 38 and a connector 39 is a projector-side connector 37 using of two or more projectors 1 in connection, the cable-side connector 39 is laid in the state received in the cutout part 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-optical axis photoelectric sensor, and more particularly, to a multi-optical axis photoelectric sensor convenient for connecting a plurality of units to form a wide light curtain, and a projector and a projector included therein. Regarding the light receiver.

[0002]

2. Description of the Related Art Conventionally, in order to detect the presence or absence of an object in a wide detection area, a multi-optical axis photoelectric sensor having a light emitter and a light receiver as one unit has been used. A typical example of using a multi-optical axis photoelectric sensor is to create a protective fence, or light curtain, with a multi-optical axis photoelectric sensor at the boundary of work areas such as machine tools, punches, presses, casting machines, and automatic controllers. When a part of the body such as the operator's fingertip invades the work area, it is detected by the multi-optical axis photoelectric sensor to immediately stop the operation of the machine and / or give an alarm to protect the operator. Used.

In order to create a light curtain with the required expanse when the boundaries of the work area are large compared to the light curtain that can be made with many light axes of a single unit multi-optical axis photoelectric sensor. It is used by connecting a plurality of units to each other.

US Pat. No. 5,198,661 to Anderson et al.
It teaches that a plurality of units are connected by a flexible cable. Specifically, a flexible cable that connects between adjacent light emitters and between adjacent light receivers is connected to an end of each light emitter and each light receiver. It is designed to connect with.

According to this connecting method using the flexible cable, the angle between the adjacent units can be freely set, so that, for example, a corner of a work area having a rectangular contour or an arc-shaped contour can be formed. It is suitable for making a light curtain along a curved portion having.

However, in this US Pat. No. 5,198,661, since the flexible cable is connected to the ends of the respective projectors and the respective receivers by using the connectors, they are on the same plane due to interference between adjacent connectors. A separation distance is generated between the adjacent light emitters and the adjacent light receivers that are arranged in the light emitting device.Therefore, the pitch between the plurality of posting elements included in the light emitter and the pitch between the plurality of light receiving elements included in the light receiver It is practically difficult to maintain the distance between the optical axes of the two adjacent optical transmitters and optical receivers. From this,
When the pitch of the light projecting elements between the adjacent light emitters and the pitch of the light receiving elements between the adjacent light receivers increase,
An undetectable area occurs in the light curtain.

In order to solve such problems, WO00 / 5
International Publication No. 4077 (PCT / US00 / 06357) prepares a molded coupler that receives an end portion of an adjacent light emitter and an end portion of an adjacent light receiver, and using this molded coupler,
It teaches connecting adjacent projectors and adjacent receivers. This molding coupler is molded by plastic so as to have a predetermined bending angle.

According to the molding coupler proposed here, since the distance between the adjacent light emitters and the adjacent light receivers arranged on the same plane can be made small and constant,
It is possible to maintain the pitch between a plurality of posting elements built into a projector and the pitch between a plurality of light receiving elements built into a light receiver, that is, the distance between the optical axes forming the light curtain, between adjacent light emitters and light receivers. There is an advantage that you can.

[0009]

[Problems to be Solved by the Invention] However, WO00
In the case of using the molded coupler disclosed in / 54077, the angle provided by the molded coupler defines the angle between the adjacent projectors and the adjacent light receivers.
There is a problem in that the flexibility of the set angle between adjacent light emitters and between adjacent light receivers is impaired, which is an advantage of using a flexible cable as in the above-mentioned US Pat. No. 5,198,661.

Therefore, an object of the present invention is to reduce the separation distance between adjacent light emitters and adjacent light receivers when a plurality of multi-optical axis photoelectric sensors are connected to each other to form a wide light curtain. Provided is a multi-optical axis photoelectric sensor, and a projector and a light receiver included in the multi-optical axis photoelectric sensor, which makes it easy to keep the distance between the optical axes forming the light curtain substantially constant between adjacent multi-optical axis photoelectric sensors. Especially.

A further object of the present invention is to freely set the bending angle between adjacent projectors and between adjacent optical receivers when a plurality of multi-optical axis photoelectric sensors are connected to each other to form a wide light curtain. It is an object of the present invention to provide a multi-optical axis photoelectric sensor and a light projector and a light receiver included in the same.

[0012]

According to the present invention, such a technical problem is that both have an elongated outer shape, and a plurality of light emitting elements and light receiving elements are arranged at equal intervals in a longitudinal direction thereof. In a multi-optical axis photoelectric sensor including a light emitter and a light receiver, the distance between the ends of the light emitter and the light receiver and the light emitter element and the light receiver element closest thereto is the pitch of the adjacent light emitter elements. The interval and the pitch interval between the adjacent light receiving elements are set to be shorter, and cutout portions extending to the ends of the light emitter and the light receiver are provided at the end portions of the light emitter and the light receiver, and a plurality of the cutout portions are provided. The connector provided at the end of the flexible cable connecting the multi-optical axis photoelectric sensors to each other is received, and the cable-side connector can be connected to the connectors provided on the projector and the light receiver. It is achieved by providing a multi-optical axis photoelectric sensor, characterized in that.

That is, according to the present invention, since the adjacent multi-optical axis photoelectric sensors are connected to each other via the flexible cable, the bending angle between these multi-optical axis photoelectric sensors can be freely set. . Further, since the cable-side connector that occupies a relatively large volume is housed in the cutout portions of the light transmitter and the light receiver, it is possible to reduce the possibility that this connector may protrude outward and cause interference between the connectors. A multi-optical axis photoelectric sensor facilitates making a light curtain with substantially evenly spaced optical axes.

[0014]

According to a preferred embodiment of the present invention, the connector on the side of the light emitter and the light receiver is arranged so as to face the cutout portion, and the connector on the side of the cable is arranged on the side of the light emitter and the light receiver. When connecting to the connector on the projector side, the access direction of the connector on the cable side is a direction inward from the ends of the projector and the receiver along the longitudinal direction of the projector and the receiver. Also, a control board for the light emitter and the light receiver is arranged adjacent to the back surface of the connector on the light receiver side.

With this arrangement of the control board, the control board can be accommodated by utilizing the dead space inside the light emitter and the light receiver, which is convenient for slimming the light emitter and the light receiver.

Further, according to a preferred embodiment of the present invention, when the cable side connector is connected to the projector and the receiver side connectors, the cable side connector is connected to the end of the projector and the receiver. It is located inward in the longitudinal direction from the end. According to this, even if the bending angle of the adjacent multi-optical axis photoelectric sensors is set to be large, it is possible to reduce the risk of mutual interference between the adjacent cable-side connectors.

According to a preferred embodiment of the present invention, the end faces of the light projector and the light receiver are constituted by curved surfaces which are convex outward. Therefore, even if the ends of adjacent multi-optical axis photoelectric sensors are connected in contact with each other, it is easy to maintain a uniform pitch interval between adjacent optical axes regardless of the bending angle between them. become. In addition to this, for example, by providing notches on the side surfaces of the light transmitter and the light receiver that face each other, the ends of the light emitter and the light receiver can be made substantially flat, so that they are adjacent to each other. Even if the pitch interval between the light projecting element and the adjacent light receiving element is narrowed, the uniformity of the pitch interval between the optical axes can be ensured. The above and other objects and advantages of the present invention will be apparent from the following description of the preferred embodiments of the present invention.

[0018]

1 shows the end of a light projector 1 of a multi-optical axis photoelectric sensor unit. Although the light receiver of the multi-optical axis photoelectric sensor unit is not shown, it should be understood that the light receiver has substantially the same appearance as the light projector 1.

The floodlight 1 has an Al case body 2 made of an extrusion molded product. The case body 2 has a hollow structure having an elongated rectangular shape with both ends open, and its occupied cross-sectional area is smaller than that of a conventional one. On one side surface 3 of the case body 2, there are provided a plurality of through holes 4 that are equally spaced from each other and are arranged side by side in a row. Of these through holes 4, every other first through hole 4a. Is for projecting light and the other second through holes 4b are tool insertion holes for operating a screw or the like for fastening or fixing a module or the like inside the case body 2. That is, every other first through hole 4
A light projecting element (not shown) is disposed so as to face a, and the optical axis of this light projecting element is substantially orthogonal to one side surface 3 of the case body 2.

Terminal members 5, which are plastic molded products, are attached to both ends of the case body 2, and the outer contour of the projector 1 is formed by the pair of terminal members 5 and the case body 2. It

The terminal member 5 has a stepped shape as can be understood from FIG. That is, the terminal member 5 has a substantially same outer shape as the case main body 2, that is, the same cross-sectional shape in the width direction as the case main body 2, and has a shape in which a part of a pair of surfaces facing each other is cut out in parallel. Is equipped with. The terminal member 5 will be described in more detail.
Has a proximal end portion 7 located adjacent to the case body 2 and having substantially the same outer shape as the case body 2, and a distal end portion 6 that extends axially outward from the proximal end portion 7.
By the step portion 8 between the distal end portion 6 and the proximal end portion 7,
Notched portions 9 are formed on the surfaces facing each other, and the two notched portions 9 extend to the end of the terminal member 5.

That is, the tip portion 6 of the terminal member 5 has a first side surface 10 which extends substantially along the surface 3 (FIG. 1) of the case body 2 in which the through hole 4 is provided, and the first side surface 10. 10
A second side surface (not shown in the drawing for drawing reasons) facing each other, and third and fourth side surfaces 11 and 12 substantially orthogonal to the first and second side surfaces, The third and fourth side faces 11 and 12 respectively form a cutout portion 9 (FIG. 2).

That is, the third and fourth side surfaces 11 and 12 of the terminal member 5 which oppose each other, that is, the two side surfaces which are substantially parallel to the optical axis without interfering with the optical axis, correspond to the step portion 8 corresponding thereto. The above-described two cutout portions 9 are formed by the above, and the third and fourth side surfaces 11 and 12 forming the cutout portion 9 correspond to the side surfaces of the base end portion 7 without interfering with the optical axis. It is made up of substantially flat surfaces that are lower than and extend parallel to each other.

A guide groove 20 having a rectangular cross section is formed at the center in the width direction of each of the third and fourth side faces 11 and 12.
The guide groove 20 extends in the longitudinal direction of the third and fourth side surfaces 11 and 12 and is open to the outside.

On the other hand, the first side surface 10 and the second side surface orthogonal to the optical axis extend substantially along the base end portion 7 of the terminal member 5 and the corresponding side surface of the case body 2, and these It is substantially flush with the side surface. An elongated transparent lens cover 15 extending in the arrangement direction of the through holes 4 of the case body 2 is attached to the first side surface 10 of the end member 5, and the lens cover 15 includes: Tool insertion holes 16 are provided at equal intervals along the longitudinal direction.

The terminal member 5 is shown in FIG.
It is mounted via a mounting member 25 also shown in FIG. The mounting member 25 is not particularly limited, but the first plate 2
6 and a second plate 27 that is bent and extended from the side edge of the first plate 26 at a substantially right angle, and has an L-shaped cross section (FIG. 3).

An elongated element holder fixing plate 30 is arranged so as to face the first plate 26 of the mounting member 25, and the element holder fixing plate 30 is the first plate 26.
Has substantially the same length dimension as and extends parallel to the first plate 26. Plate for fixing element holder 3
0 has a plurality of through holes 31 arranged at equal intervals in a row along the longitudinal direction.
1 are spaced from each other at the same pitch as the through holes 4 of the case body described above.

Reference numeral 32 shown in FIGS. 2 and 3 is an element holder incorporating a light projecting element, and the element holder 32 is
The base end is fitted into the cylindrical receiving portion 26a of the first plate 26, and the free end of the element holder 32 is supported by the through hole 31 of the element holder fixing plate 30.

That is, the cylindrical receiving portions 26a of the first plate 26 are arranged at the same pitch as the first through holes 4a of the through holes 4 of the case body 2. On the contrary,
The through hole 31 of the element holder fixing plate 30 includes a third through hole 31a that matches the first through hole 4a of the case body 2,
It includes a tool insertion hole 4b and a fourth through hole 31b that coincides with the tool insertion hole 4b.

The first plate 26 and the element holder fixing plate 30 are positioned in the case body 2 on one side (the left side in FIG. 3) and on the other side (see FIG. 3).
(The right side portion of) is positioned in the terminal member 5.

An amplifier 35 is attached to the attachment member 25 on the plate surface of the first plate 26 facing the element holder fixing plate 30. The mounting position of the amplifier 35 is not particularly limited, but the first plate 26
The case body 2 side is preferable. That is, the amplifier 3
5 is the first plate 26 and the element holder fixing plate 3
It is a space sandwiched between 0 and, and is preferably arranged between the adjacent element holders 32 and 32, whereby
It is possible to accommodate the components using the dead space, and the projector 1 can be downsized, that is, slimmed down.

On the second plate 27, the case body 2
The light emission control board 36 is attached to the side, and the terminal member 5
The projector side connector 37 is attached to the side, and the projector side connector 37 is covered by the base end portion 7 of the terminal member 5. The projector side connector 37 has a connecting surface with the corresponding cable side connector 39 facing the end edge of the terminal member 5. That is, the connecting surface of the projector-side connector 37 faces outward in the longitudinal direction of the terminal member 5, and the control board 36 is disposed adjacent to the rear surface of the projector-side connector 37.

In the light projector 1 having the above-described structure, the light projecting element (not shown), that is, the element holder 32, which is arranged so as to face one side surface including the case body 2 and the terminal members 5 located at both ends thereof, The adjacent light projecting elements are spaced at the same pitch. The distance d1 (see FIG. 1) between the element holders 32 (light emitting elements) located at both ends of the light projector 1 and the end of the light projector 1 is considerably larger than the distance d2 between the adjacent light emitting elements. It is small and d1 is equal to (1/2) d2 or slightly smaller than (1/2) d2.

Further, the projector 1 is provided with a projector side connector 37 at an end portion thereof, that is, a base end portion 7 of the terminal member 5, and a connecting port or connecting surface of the projector side connector 37 has a cutout portion of the terminal member 5. It faces the outside of the projector 1 in the longitudinal direction of the projector 1.

Therefore, when a plurality of light projectors 1 are used in combination, the cable-side connector 39 provided at the end of the flexible cable 38 is connected to the third side surface of the terminal member 5 from the outside in the longitudinal direction of the light projector 1. It may be connected to the projector side connector 37 while sliding along 11 (see FIGS. 2, 3 and 5). At this time, the cable side connector 39
Becomes close to the stepped portion 8 and is received by the cutout portion 9 of the terminal member 5 (see FIGS. 1 and 2).

When connecting the cable-side connector 39 to the light-emitter-side connector 37, it is preferable to guide the cable-side connector 39 by utilizing the guide groove 20 on the third side surface 11 of the terminal member 5. In order to realize it, the protrusion 4 having a shape complementary to the guide groove 20 is formed on the bottom surface of the cable-side connector 39 facing the third side surface 11 of the terminal member 5.
0 (FIG. 4) should be provided.

The cable side connector 39 is preferably provided with a size that does not largely project outside the terminal member 5 when it is connected to the projector side connector 37, as can be understood from FIG. 1 and the like. In other words, it is preferable that the depth of the cutout portion 9 of the terminal member 5 (the height of the step portion 8) and the height of the cable side connector 39 are the same. In other words, when the cable-side connector 39 is connected to the floodlight 1, the cable-side connector 39 substantially becomes a part of the outer shape of the floodlight 1, and the outer contour of the base end portion 7 of the case body 1 or the terminal member 5. It is preferable that the outer shape of the cable-side connector 39 is such that it can be extended as it is.

FIG. 5 shows an example of connecting two multi-optical axis photoelectric sensor units to form a light curtain. Reference numeral 45 in FIG. 5 indicates a light receiver. As described above, the light receiver 45 has substantially the same outer shape as the light projector 1, and the mechanism and structure for connecting the adjacent light receivers 45 with each other using the flexible cable 38 are as follows. It is the same as the floodlight 1. FIG. 5 shows a state in which the two projectors 1 and 1 are connected to each other using the flexible cable 38, and immediately before the two light receivers 45 and 45 are connected to each other using the flexible cable 38. Indicates the state of.

The same applies to the light receiver 45, but taking the light projector 1 as an example, when the cable-side connector 39 is accommodated in the cutout portion 9 of the terminal member 5, the cable-side connector 39 is connected to the cable side. The end 39a is the terminal member 5
Is largely separated from the edge (distance D shown in FIG. 2), and is located inward in the longitudinal direction from the edge of the terminal member 5. Accordingly, the end faces of the adjacent projectors 1 can be arranged in a state of being in contact with each other, and the pitch (d1) is substantially the same over the entire length of the plurality of projectors 1 connected to each other via the cable 38. The light projecting element can be arranged by. That is, it is possible to make a wide light curtain composed of a plurality of optical axes having substantially the same pitch.

Cable-side end 3 of the cable-side connector 39
The separation distance D between 9a and the end edge of the terminal member 5 is such that the bending angle between the adjacent projectors 1 is at least 9.
The distance is preferably such that interference between the cable-side connectors 39 does not occur at 0 degree, and more preferably, the bending angle between the adjacent projectors 1 and 1 is considerably smaller than 90 degrees. Even at this time, it is preferable that the distance is such that interference between the cable-side connectors 39 does not occur.

The end surface 5a of the terminal member 5 of the projector 1 is directed outward when it is sectioned along the longitudinal axis of the terminal member 5 in parallel with the first side surface 10 to which the lens cover 15 is attached. It may be a convex arc surface or a curved surface. By providing the projector 1 with the end surface 5a formed of an arc surface,
Even if the intersecting angles of the adjacent projectors 1 arranged on the same plane are arbitrarily set, substantially the same pitch (see FIG.
The light projecting element can be arranged in d2).

In other words, the end surface 5a of the terminal member 5 is constituted by an arc surface or a curved surface, and one end edge of the arc surface or the curved surface is made continuous with the notch portion 9a for receiving the cable side connector 39. , Since the other edge is continuous with the other cutout portion 9b and has a symmetrical shape,
No matter which side the adjacent light projectors 1 and 1 are bent in, the pitch intervals of the light emitting elements between the adjacent light projectors 1 and 1 can be kept uniform.

This is effective when the pitch between adjacent light projecting elements is set to be relatively small. Therefore, in the projector 1 according to the embodiment, the projector 1 has a slim shape and projects at a small pitch. Optical elements can be placed. In addition, this slimming is due to the adjacent element holders 32,
This is achieved by arranging the amplifier 35 between 32 and arranging the control board 36 adjacent to the back surface of the connector 37 and arranging the built-in components of the projector 1 by utilizing the dead space. Therefore, for example, when the pitch of the light projecting elements is relatively large, the outer shape of the terminal member 5 can be designed by omitting the other notch portion 9b.

FIG. 6 shows a modification of the mounting member 25 described above.
Shown in. The mounting member 50 of the modified example shown in FIG. 6 extends at a right angle from the other side edge of the first plate 26 and faces the second plate 27 in addition to the first plate 26 and the second plate 27 described above. And a third plate 51 located at the position. In the mounting member 50 shown in FIG. 6, by mounting the light projecting control board and / or the amplifier on the third plate 51, the dead space existing in the arrangement space of the element holder 32 can be utilized. Only the projector-side connector 37 may be attached to the 2 plate 27.

Further, regarding the mounting member 50 shown in FIG.
All of the second plate 27 of the mounting member 50 may be removed, or the end member 5 side of the second plate 27 may be removed. When all of the second plate 27 is removed, the light projection control board 20 may be attached to the third plate 51.

FIG. 7 shows a mounting member 55 from which a part of the second plate 27, that is, the terminal member 4 side is removed. When such a mounting member 55 is used, as shown in FIG. 7, the projector side connector 37 is mounted on the third plate 51, and the connecting surface of the projector side connector 37 is directed to the side of the terminal member 5. May be.

The projector side connector 3 as shown in FIG.
When the arrangement of 7 is adopted, an opening (not shown) is provided in the third side surface 11 of the terminal member 5, and the cable-side connector 39 is provided at the side of the terminal member 5, that is, the third side surface through the opening.
It can be accessed from the vertical direction of the side surface 11 (direction shown by the arrow in FIG. 7).

FIG. 8 shows a modification of the cable side connector 39 in the access direction. Up to now, the first specific example (FIG. 5) in which the cable side connector 39 is moved along the plate surface of the third side surface 11 of the terminal member 5 to access the projector side connector 37, and the cable side connector 39 is terminated. Member 5
Second specific example in which the projector side connector 37 is moved by moving the third side surface 11 in the vertical direction (FIG. 7)
And explained.

In the example shown in FIG. 8, the terminal member 5 is moved along a plane common to the third side surface 11 and in a direction perpendicular to the longitudinal direction thereof (direction of arrow in FIG. 8) to the projector side. An example of accessing the connector 37 is shown. That is, in the example shown in FIG.
The first plate 26 for holding the element holder 32
The connection surface of the projector-side connector 37 is oriented vertically with respect to the plate surface of the first plate 26. Since the projector-side connector 37 is provided on the first plate 26 having a relatively high rigidity, it is easy to increase the supporting rigidity. Of course, such a projector side connector 37
When attaching the first side surface 1 of the terminal member 5,
0 may be provided with an opening through which the cable side connector 39 can enter.

Further, when the access method of FIG. 8 is adopted, in this case, the light emitting control board and / or the amplifier is attached to the third plate 51 arranged on the side opposite to the cutout portion 9a, whereby the element The dead space existing in the arrangement space of the holder 32 can be used. Therefore, from the mounting member 25 or the mounting member 50 described above and the modified example thereof, a part of the first plate 26, that is, the terminal member 5 is formed.
The side portion may be removed, or all of the first plate 26 may be removed.

As described above, mainly on the projector 1, the cable side connector 3 is formed in the structure of the end portion of the projector 1, that is, the cutout portion 9.
Although the structure for accommodating 9 and the access direction of the cable side connector 39 have been described, this can be similarly applied to the light receiver 45. Further, regarding the tip portion 6 of the terminal member 5, in the above description, the notch portion 9 is formed in the two portions of the one terminal member 5 that face each other with the third side surface 11 and the fourth side surface 11. Although an example has been described with reference to the drawings, only one notch 9 may be formed in the terminal member 5 to accommodate the cable-side connector 39.

An application example of the photoelectric sensor unit by the cable connection method described with reference to FIGS. 1 to 8 will be described with reference to the drawings after FIG. FIG. 9 shows the projector 1 and the receiver 4.
It is explanatory drawing of the most basic structure which makes a light curtain with the single unit which consists of 5. In the drawings such as FIG. 9, the end structures (notched portion 9) of the light projector 1 and the light receiver 45 and the connectors 37 and 39 are omitted in order to avoid complication of the diagram.

Both the light projector 1 and the light receiver 45 are provided with an optical axis adjustment display section 60 in which a plurality of light emitting diode (LED) segments are vertically arranged side by side in the case body 2.
For the D segment, for example, a two-color light emitting diode that emits red or green light is adopted. In addition, the case body 2 emits green light during normal times, while it emits red light when an unplanned optical axis other than normal times blocks or receives light, or when the system itself fails. An output indicator lamp, that is, an on / off indicator lamp 61, which is an LED that emits light, is provided.

The display format of the optical axis adjustment display section 60 composed of a plurality of light emitting diode segments is not particularly limited, but for example, the optical axis 62 of the projector 1 forming the unit is entirely incident on the light receiver 45. , All LED segments emit green. Some optical axes 62
When is blocked, a number of segments corresponding to the proportion of the shielded optical axis 62, in other words, the proportion of the incident optical axis, emits red light from the bottom, and the number of segments corresponds to the shielded optical axis 62. The segment goes off from the top. That is, a red bar is displayed in a bar format in which the red bar extends upward as the light entrance rate increases or according to the degree of the optical axis adjustment.

Referring to FIG. 2, the light projector 1 scans the N light projecting circuits 102 for driving the light projecting element 101 including N light emitting diodes and the light projecting circuits 102 in a time division manner. The light emitting element switching circuit 103 and the light emitting device control circuit 104 for controlling the light emitting device 1 as a whole are provided. From the light emitting device control circuit 104, the optical axis adjustment display unit 60 and the output indicator lamp 6 are provided.
The control signal is output to 1.

Further, a clock signal from the clock generation circuit 105 is input to the projector control circuit 104, and the projector timing for causing the N projector elements 101 to sequentially emit light is generated. That is, the N light projecting elements 101 are, for example,
Referring to FIG. 1, light is emitted sequentially from the lowermost light projecting element 101 toward the uppermost light projecting element 101 at a predetermined timing.

The projector 1 further includes a first projector communication control circuit 10 for controlling bidirectional signal transmission / reception with the light receiver 45.
6 and a second projector communication control circuit 107 for controlling communication between the projectors (not shown in FIG. 9) connected in series,
A timing receiving circuit 108 for receiving a timing signal with another light receiver (not shown in FIG. 9) connected in parallel is provided.

On the other hand, the light receiver 45 includes N light receiving circuits 2022 for driving the light receiving elements 201 composed of N light emitting diodes and the like, and a light receiving element switching circuit 203 for time-divisionally scanning these light receiving circuits 2022. Amplifier circuit 204
And a photoreceiver control circuit 205 for controlling the photoreceiver 45 as a whole.
A control signal is output to the output indicator lamp 61.

A signal from the clock generation circuit 206 is input to the photoreceiver control circuit 205 to enable the N photodetectors 201 to sequentially receive light and the selected photodetector 20.
Lights other than 1 cannot be received. That is, N light receiving elements 2
For example, with reference to FIG. 9, for 01, a state in which light can be received is generated sequentially from the lowermost light receiving element 201 toward the uppermost light receiving element 201 at a predetermined timing.

The light receiver 45 further controls the first light receiver communication control circuit 20 for controlling bidirectional signal transmission / reception with the light projector 1.
7, and a second photoreceiver communication control circuit 208 for controlling communication between the photoreceiver (not shown in FIG. 9) connected in series,
Timing transmission circuit 2 for transmitting a timing signal to a projector (not shown in FIG. 9) of another unit connected in parallel
09 and. The light-shielding signal generated by the light-reception control circuit 205 is transmitted via the output circuit 210 to, for example, a control unit of a press device surrounded by a light curtain formed by the light projector 1 and the light receiver 45, and an external device such as a warning light. (Not shown).

FIG. 11 shows an example of connecting a plurality of units by using a unit of the multi-optical axis photoelectric sensor consisting of the light projector 1 and the light receiver 45. The unit located at the lower left of FIG. 11 will be mainly described. With respect to the unit at the lower left, the number of units is not particularly limited, but two units are added in series to form a first series unit group. Are formed. Also, the lower right unit is added in parallel to the lower left unit in FIG. 11, and one unit is added in series to the lower right unit, although the number of units is not particularly limited. There is.

In the system illustrated in FIG. 11, the unit of the first series group located on the left side is marked with "L", and the unit of the second series group located on the right side which is added in parallel is marked with "L". Units belonging to each group are sequentially numbered from bottom to top to identify them.

The lowest unit L1 of the first series group operates as a master unit for the expansion units L2 and L3 of the first series group. On the other hand, the lowest unit R1 of the expanded second series group operates as a master unit with respect to the expanded unit R2 of the second series group.

First, the wiring of the first series group will be described. The projector 1 and the light receiver 45 of the parent unit L1 of the first group are the inter-unit communication line CL formed of the flexible cable 38.
Connected by 1.

The parent unit L1 of the first group and the second unit L2, which is the first child unit shown above, are connected in series such that the projectors 1 and the receivers 45 are made of flexible cables 38. They are connected by the extension communication line CL2.

The second unit L2 and the third unit L3, which is the second child unit shown above, are connected to each other by the transmitter 1 and the light receiver 45, which are flexible cables 38 for serial extension communication. It is connected by the line CL2.

Next, the additional second series group on the right side of FIG. 11 will be described. The projector 1 and the light receiver 45 of the first unit (parent unit of this second series group) R1 are the parent units of the first group. Similar to L1, they are connected by an inter-unit communication line CL1 including a flexible cable 38.

The parent unit R1 of the second group and the second unit R2, which is the child unit illustrated above, are the projector 1
The two and the light receivers 45 are connected to each other by a serial extension communication line CL2 including a flexible cable 38.

Finally, the connection between the first series group and the second series group, which is added in parallel to the first series group, will be described. The parent units L1 and R1 of each series group are as follows. And then connected. That is, the light receiver 45 of the first group parent unit L1 and the light projector 1 of the second group parent unit R1 are connected by the parallel connection communication line CL3 including the flexible cable 38.

The connection relationship of these plural units is shown in FIG.
Best understood from 2. That is, the first
In the serial group, the parent unit L1 and the second unit L2 are the second projector communication control circuit 107 of the parent unit L1.
And the first floodlight communication control circuit 106 of the second unit L2.
And are connected by a serial extension communication line CL2,
The second optical receiver communication control circuit 208 of the parent unit L1 and the first optical receiver communication control circuit 207 of the second unit L2 are connected by the serial extension communication line CL2.

Similarly, in the second unit L2 and the third unit L3, the second floodlight communication control circuit 107 of the second unit L2 and the first floodlight communication control circuit 106 of the third unit L3 perform serial extension communication. Connected by line CL2,
In addition, the second light receiver communication control circuit 20 of the second unit L2
8 and the first light receiver communication control circuit 20 of the third unit L3
7 are connected by a serial extension communication line CL2.

The same applies to the second series group, and the parent unit R1 and the extension unit R2 are the second unit of the parent unit R1.
The projector communication control circuit 107 and the first unit of the second unit R2
The projector communication control circuit 106 is connected to the serial extension communication line CL2.
The second optical receiver communication control circuit 208 of the first unit R1 and the first optical receiver communication control circuit 207 of the second unit R2 are connected by the serial extension communication line CL2.

The first series unit group and the expanded second series unit group are connected as follows. That is,
The timing transmission circuit 209 of the light receiver 45 of the parent unit L1 of the first group and the timing transmission circuit 108 of the projector 1 of the parent unit R1 of the second group are connected by the parallel extension communication line CL3.

In the plurality of units connected to each other as described above, a signal is output to the external device by the output line 211 connected to the output circuit 210 of the parent unit L1 and the extension parent unit R1 for each group. (FIG. 12).

In the parent unit L1 of the first group, first,
The projector control circuit 104 generates synchronization timing, and this synchronization timing is transmitted via the inter-unit communication line CL1.
Through the light receiver communication control circuit 207, the light receiver control circuit 20
5, the N light projecting circuits 102 and the light receiving circuits 20 of the projector 1 and the light receiver 45 of the parent unit L1 of the first group are sent.
2 operates in order. Further, the light receiver control circuit 205 displays the light receiving state and the output (light shielding) state by the optical axis adjustment display unit 60 and the output indicator lamp 61, and this display data is input to the light projector control circuit 104, and the light projector 1 also The same display as that of the corresponding light receiver 45 is performed.

Regarding the light projecting / receiving of light in a plurality of units, the timing signals of light projecting and light receiving are first transmitted from the parent unit L1 of the first group to the units of the first series group.
3 is supplied. That is, the light emission completion signals in all the light emitting elements 101 of the first series unit group are transmitted from the first communication control circuit 106 of the light projector 1 of the parent unit L1 to the first communication control circuit 207 of the light receiver 45 of the parent unit L1. Is input to the photoreceiver control circuit 205 via. On the other hand, the light reception completion signal of all the light receiving elements 201 of the first series unit group is input to the light receiver control circuit 205. As a result, in the light receiver control circuit 205 of the parent unit L1,
When a normal light emitting / receiving operation is confirmed by the light emitting completion signal from the first communication control circuit 106 of the light projector 1 and the light receiving completion signal in all the light receiving elements 201, a timing signal generation command signal is transmitted to the timing transmission circuit 209. The timing transmission circuit 209 receives this command signal, and transmits the timing signal to the timing reception circuit of the projector 1 of the extension parent unit R1 of the second series unit group via the parallel extension communication line CL3. As a result, when the projection of the units of the first series group is completed, the projection of the units of the second series group is started.

That is, in response to an instruction from the parent unit L1 of the first group, first, the light projecting / receiving of the additional parent unit R1 in parallel is started, and the N light projecting circuits 102 and the light receiving circuits 202 of this parent unit R1 are When all the light receptions of the first unit R1 are completed, the information is transmitted to the projector 1 and the light receiver 4 of the parent unit R1 of the second series unit group.
5 is transmitted to the second projector communication control circuit 107 and the second light receiver communication control circuit 208 provided in FIG. The second light emitter communication control circuit 107 and the second light receiver communication control circuit 208, which have respectively received the light emission completion signal and the light reception completion signal of the extension parent unit R1, receive this signal and receive the child unit R2 of the second series unit group. Communication control circuit 106 of the floodlight 1
And a timing signal to the first communication control circuit 207 of the light receiver 45, respectively. The timing signal is sent to the first communication control circuit 106 of the projector 1 of the slave unit R2 and the first of the photoreceiver 45.
Upon reception by the communication control circuit 207, the N light projecting circuits 102 and the light receiving circuits 202 of this child unit R2 operate in sequence. When all the light emitting and receiving of the second series unit group is completed in this way, the light emitting and receiving of the first series unit group is started again.

Here, as a method for starting the light emission / reception of the first series unit group again, the completion of all the light transmission / reception in the second series unit group is completed by parallelly receiving the light receiving element control circuit of the extension parent unit R1. 205, and the first light receiver communication control circuit 207 of the parent unit R1 based on the recognition.
In addition, the timing signal may be returned to the parent unit L1 of the first series unit group via the first communication control circuit 106, or a timer may be set in the first series unit group and the second series unit After the timing signal is transmitted to the series unit group, the light emission / reception of the first series unit group may be started after the time required for all the light emitting / receiving operations of the second series unit group has elapsed. As described above, in a system in which a plurality of series unit groups are connected in parallel, the operation of the downstream side series unit group is started after the light emitting / receiving operation of the upstream side series unit group is completed. Therefore, it is possible to prevent the projection of one unit from affecting the other units.

An optical axis adjustment display section 60 and an output indicator lamp 61 included in all units are provided, and the display is controlled by the control means of each unit, that is, the light receiving element control circuit 205. Display data relating to these displays is supplied to the parent units L1 and R1 for each group via the serial extension communication line CL2. That is, the parent units L1 and R1 of each group communicate not only to unify the display between the projector 1 and the light receiver 45 included in the parent units L1 and R1 but also to the child units added in series. Even during the period, the display of the optical axis adjustment display unit 60 and the output indicator lamp 61 can be substantially controlled through the serial extension communication line CL2, so that the units for each unit can be controlled within a predetermined communication cycle. Time is allotted and data is exchanged with other units in order.

For example, the display data in the photoreceiver 45 of the upper left unit of FIG. 11, that is, the photoreceiver 45 of the third unit L3 of the first series group is, in order, the photoreceiver 45 of the second unit L2, the photoreceiver 45 of the parent unit L1, and the photoreceiver 45 of the parent unit L1. Projector 1 of unit L1,
The light is transmitted to the projector 1 of the second unit L2 and the projector 1 of the third unit L3. As a result, the displays of the light projector 1 and the light receiver 45 of the third unit L3 are unified. That is, regarding the optical axis adjustment display section 60 of the third unit L3,
When light blocking occurs in the third unit L3, the light blocking state is displayed by the optical axis adjustment display section 60 provided in both the light projector 1 and the light receiver 45 of the third unit L3.

With respect to the output indicator lamp 61 of the third unit L3 of the first group, the data regarding the output display is uniformly displayed in all the units of the first series group.
That is, when the light blocking occurs in the third unit L3, not only the third unit L3 but also the parent unit L3
1 and all the projectors 1 and receivers 45 of the second unit L2
The output indicator lamp 61 provided in the lamp emits red light to display the off output state.

The present invention relates to controlling the output indicator lamp 61 in a unitary manner by dividing each group into a first series group and a second series group. For example, when the unit stops operating in an error state, and Alternatively, the display may be turned on during teaching by blanking or when the teaching is completed, and another display means for displaying these is provided on at least one of all the projectors 1 and the photoreceivers 45. You may do it.

In the optical axis adjustment display section 60 which is independently displayed for each unit, when the unit fails, this is displayed using the optical axis adjustment display section 60 of the failed unit. You may In addition, when only one optical axis is shielded, the optical axis adjustment display section 6 of the shielded unit is displayed.
You may make it display 1 optical-axis shading by 0. In addition, when, for example, dust adheres to the lens attached to the light projecting element 101 or the light receiving element 201 and the amount of light becomes insufficient, only the optical axis adjustment display unit 60 of the unit having the insufficient amount of light is used. It may be displayed.

[Brief description of drawings]

FIG. 1 is a partial perspective view showing an end of a light projector of a multi-optical axis photoelectric sensor of an embodiment.

FIG. 2 is a view showing a case body removed from an end portion of the projector shown in FIG.

FIG. 3 is a diagram showing a case body and a terminal member both removed from an end portion of the floodlight of FIG.

FIG. 4 is a diagram showing a terminal member removed from an end portion of the projector shown in FIG.

FIG. 5 is a view for explaining connecting the multi-optical axis photoelectric sensor of the first embodiment using a flexible cable.

FIG. 6 is a perspective view showing a mounting member incorporated in the floodlight of FIG. 1 in an extracted manner.

FIG. 7 is a diagram corresponding to FIG. 4 for explaining a modified example of the access direction of the cable side connector.

FIG. 8 is a diagram corresponding to FIG. 4 for explaining various modified examples of the access direction of the cable side connector.

FIG. 9 is an explanatory diagram related to a specific connection when a light curtain including a single unit of a multi-optical axis photoelectric sensor to which the present invention is applied is manufactured.

10 is an internal block diagram of a light projector and a light receiver which form the unit shown in FIG.

FIG. 11 is a diagram for explaining a connection method in the case of forming a plurality of independent wide light curtains using the multi-optical axis photoelectric sensor to which the present invention is applied.

FIG. 12 is a block diagram corresponding to FIG. 11.

[Explanation of symbols]

1 Floodlight 2 Case body 5 Terminal member 5a Curved end face of terminal member 6 Tip of terminal member 7 Base part of terminal member 8 Steps of terminal member 9 Notch part of terminal part 20 guide groove 25 Mounting member 30 Element holder fixing plate 37 Floodlight side connector 38 Flexible cable 39 Cable side connector

Claims (8)

[Claims] 1. A multi-optical axis photoelectric sensor comprising a light projector and a light receiver, both of which have an elongated outer shape, and a plurality of light emitting elements and light receiving elements are arranged at equal intervals in a longitudinal direction thereof. The distance between the end of the light emitter and the light receiver and the light emitting element and the light receiving element closest thereto is set shorter than the pitch interval of the adjacent light emitting elements and the pitch interval of the adjacent light receiving elements, At the ends of the light emitter and the light receiver, cutout portions extending to the ends of the light emitter and the light receiver are provided, and at the cutout portion, ends of a flexible cable connecting a plurality of multi-optical axis photoelectric sensors to each other. A multi-optical axis photoelectric sensor, wherein the connector provided on the cable is received, and the cable-side connector is connectable to the connectors provided on the projector and the light receiver. 2. The cutout portion is formed on a side surface of the light emitter and the light receiver, which are positioned parallel to the light axes of the light emitter and the light receiver, so as not to interfere with the light axis. The multi-optical axis photoelectric sensor according to claim 1. 3. The cable-side connector is located inward in the longitudinal direction from the end of the projector and the end of the light receiver when the cable-side connector is connected to the connector on the sender and the receiver side. Claim 1 characterized by the above.
Alternatively, the multi-optical axis photoelectric sensor of 2. 4. The connector on the side of the projector and the receiver is arranged so as to face the cutout portion, and the connector on the cable side is connected to the connectors on the side of the projector and the receiver The access direction of the connector is a direction inward from the ends of the light emitter and the light receiver along the longitudinal direction of the light emitter and the light receiver, and is adjacent to the rear surface of the connector on the light emitter and light receiver side. The multi-optical axis photoelectric sensor according to any one of claims 1 to 3, wherein a control board for the light projector and the light receiver is arranged. 5. The access direction of the cable side connector is a direction orthogonal to the longitudinal direction of the light emitter and the light receiver when the cable side connector is connected to the connectors on the light emitter side and the light receiver side. The control board for the light emitter and the light receiver is disposed on the side of the light emitter and the light receiver that faces the cutout portion.
A multi-optical axis photoelectric sensor according to any one of 1. 6. The multi-optical axis photoelectric device according to claim 1, wherein the end faces of the light projector and the light receiver are formed by curved surfaces that are convex outward. Sensor. 7. A light projector included in the multi-optical axis photoelectric sensor according to any one of claims 1 to 6. 8. A light receiver included in the multi-optical axis photoelectric sensor according to claim 1.