JP2004311384A - Multiple optical axis photoelectric sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multiple optical axis photoelectric sensor in which optical axes can be arranged adjacent to the end of a case. <P>SOLUTION: The multiple optical axis photoelectric sensor 1 is constituted of a case main body 2 composed of a slender extrusion-molded product made of aluminum, and an end-part case 4 composed of a molded product made of Zn alloy at its both ends. An element holder part 41 of an optical system unit 40 is surrounded by a shielding member 90 (92), and the end part of the optical system unit 40 is surrounded by an insulator 95 which is a molded product. As for the element holder part 41 of the optical axis of the outermost end, the insulator 95 is interposed between the shielding member 90 (92) surrounding it and an end of the end part case 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a multi-optical axis photoelectric sensor.
[0002]
[Prior art]
The multi-optical axis photoelectric sensor includes a light emitter and a light receiver that are arranged to face each other, and forms a light curtain between the light emitter and the light receiver. For example, when a part of the human body blocks the light curtain, the multi-optical axis photoelectric sensor issues a light blocking signal, thereby taking safety measures such as stopping the operation of the mechanical system located in the space partitioned by the light curtain.
[0003]
[Patent Document 1]
JP 2003-16891 A
[0004]
Patent Document 1 discloses that a case of a multi-optical axis photoelectric sensor is constituted by a case main body and an end case made of a plastic material connected to both ends thereof, and that an optical axis is provided also in this end case. is suggesting. Further, Patent Document 1 proposes that a concave portion having a shape in which a part of an end case is cut out is formed, and an external connector is positioned in the concave portion.
[0005]
Meanwhile, there is a technical demand for a multi-optical axis photoelectric sensor to shorten the distance between optical axes (optical axis pitch) and increase the optical axis density of a light curtain in order to improve safety. Also, a light curtain is often made by connecting a plurality of multi-optical axis photoelectric sensors with a cable, but the optical axis pitch between adjacent multi-optical axis photoelectric sensors, that is, the outermost of one of the multi-optical axis photoelectric sensors. Maintaining a small pitch between the optical axis located at the end and the optical axis located at the outermost end of the other multi-optical axis photoelectric sensor is an important technical requirement for maintaining the optical axis density of the light curtain. It has become.
[0006]
[Problems to be solved by the invention]
In order to meet such demands, it is necessary to reduce the distance between the outermost optical axis of the multi-optical axis photoelectric sensor and the end of the sensor case. easy.
[0007]
In particular, providing the optical axis in the end case of the multi-optical axis photoelectric sensor and incorporating the circuit board makes the internal space of the end case cramped, and a part of the end case. When the configuration in which the external connector is positioned in the concave portion having the shape of notch is adopted, the internal space of the end case tends to have more and more margins.
[0008]
For example, if the end case is made of a conductive material such as a metal, the above-described decrease in the withstand voltage is likely to occur. If the end case and the case body are screwed, the internal thread is formed by the screw portion. Since the space is further reduced, the withstand voltage is more easily reduced.
[0009]
From such a problem, it has been necessary to take measures such as slimming down the case of the multi-optical axis photoelectric sensor and positioning the outermost optical axis at some distance from the end of the case.
[0010]
An object of the present invention is to provide a multi-optical axis photoelectric sensor in which an optical axis can be arranged adjacent to an end of a case.
[0011]
Another object of the present invention is to provide a multi-optical axis photoelectric sensor capable of making a case slim.
[0012]
A further object of the present invention is to provide a multi-optical axis photoelectric sensor capable of preventing a malfunction by preventing an unnecessary current from flowing beforehand.
[0013]
[Means for Solving the Problems]
According to the present invention, such a technical problem
An optical system unit including an element holder portion that supports each of the plurality of optical elements and a circuit board, and arranging the optical elements in a line at an interval from one end to the other end;
A case body surrounding a central portion of the optical system unit;
An end case connected to an end of the case main body and surrounding an end of the optical system unit,
This is achieved by providing a multi-optical axis photoelectric sensor, wherein an insulator is interposed between the end case and the optical system unit. That is, the present invention is characterized in that an insulator is interposed at least in a portion where the withstand voltage is likely to be reduced, particularly in the end case where there is no room in the internal space.
[0014]
Further features of the invention and its technical advantages will become apparent from the following detailed description of the preferred embodiments of the invention.
【Example】
FIG. 1 is a perspective view of a multi-optical axis photoelectric sensor according to an embodiment. In the multi-optical axis photoelectric sensor 1, a light projector and a light receiver have substantially the same shape. Therefore, the description of the multi-optical axis photoelectric sensor 1 is a description of both the light projector and the light receiver. Particularly, when a technical matter related to the light projector or the light receiver is described, the technical matter is described by describing the fact. Alternatively, a light receiver will be described.
[0015]
The multi-optical axis photoelectric sensor 1 has a case main body 2 made of a conductive material. Specifically, the case main body 2 is formed of an elongated extruded product made of aluminum. The case body 2 has a substantially U-shaped cross section with both ends and a front face opened (FIG. 2), and has a smaller occupied cross-sectional area than conventional ones and is slim. The open front surface of the case main body 2 constitutes a window 3 (FIG. 2) for projecting or receiving light extending continuously in the longitudinal direction.
[0016]
At both ends of the case body 2, there are end cases 4 made of a conductive material, respectively. Specifically, the end case 4 is formed of a molded product made of a Zn alloy, and the outer contour of the multi-optical axis photoelectric sensor 1 is formed by the pair of end cases 4 and the case main body 2. A window for projecting or receiving light is formed on the front surface of the end case 4. That is, in the multi-optical axis photoelectric sensor 1, the optical element is accommodated not only in the case main body 2 but also in the end case 4, whereby the optical axis of the multi-optical axis photoelectric sensor 1 is set to the closed end of the one end case 4. To the closed end of the other end case 4 are arranged in a line at equal intervals (20 mm pitch or 14 mm pitch).
[0017]
The front cover adhered to the front surface of the multi-optical axis photoelectric sensor 1 via an adhesive includes a first front cover 5 covering the front surface of the case body 2 and a second front cover 6 covering the front surface of the end case 4. It is configured. A metal cross member 7 is attached to the boundary between the first front cover 5 and the second front cover 6, and the cross members 7 press the edges of the first and second front covers 5, 6. As a result, the first and second front covers 5 and 6 are pressed against the case body 2 and the end case 4.
[0018]
As described above, the case of the multi-optical axis photoelectric sensor 1 is divided into three parts 2, 4, and 4, and accordingly, the front cover is divided into three parts 5, 6, and 6. As compared with the case where one front cover is used, the total length of the front cover can be shortened, so that the influence of the thermal expansion difference between the sensor case (particularly, the case body 2) and the front cover can be reduced. it can.
[0019]
The end case 4 has an outer shape in which a part on the front side is cut out without interfering with the optical axis, and the partial cutout forms a recess for disposing the external connector 8 (FIG. 3). A place 9 (FIG. 1) is formed. When the external connector 8 is attached, the external connector 8 fills the recess 9 of the end case 4 and becomes integral with the end case 4 to form a common cross-sectional shape with the case main body 2.
[0020]
The end case 4 has a receptacle 10 capable of receiving an external connector 8 (FIG. 1). The insertion port 10 is open toward the front side, and an internal connector 81 (FIGS. 10 and 11) is arranged facing the insertion port 10. The external connector 8 is moved from the front side to the rear side along the optical axis (in the direction of the arrow in FIG. 3) and inserted into the insertion port 10 so that the external connector 8 is connected to the internal connector 81. The cable 12 extending from the external connector 8 can extend laterally from an end of the multi-optical axis photoelectric sensor 1. That is, the cable 12 extends to the rear side of the multi-optical axis photoelectric sensor 1 through the notch 4a crossing the end case 4 (FIG. 3).
[0021]
The cable 12 not only supplies power to the multi-optical axis photoelectric sensor 1 but also connects a pair of light emitters and receivers 20 and 30 in series or parallel using the cable 12 as shown in FIG. Although the light curtain can be made, the multi-optical axis photoelectric sensor 1 (the light projecting device 20 and the light receiving device 30) is connected to each other by the flexible cable 12, so that the adjacent multi-optical axis photoelectric sensor 1 is used. The bending angle between the two is arbitrary. In addition, since the flexible cable 12 extends from the notch 4a to the back side, in other words, the flexible cable 12 extends outward from the end of the multi-optical axis photoelectric sensor 1 in the longitudinal direction. Therefore, the flexible cable 12 does not interfere when the multi-optical axis photoelectric sensors 1 are arranged in an L-shape in a state where the ends of the adjacent multi-optical axis photoelectric sensors 1 are close to each other.
[0022]
The number of optical elements (light projecting elements or light receiving elements) incorporated in the illustrated multi-optical axis photoelectric sensor 1 and the separation distance (pitch) can be set arbitrarily. In the illustrated example, the pitch is 20 mm or 14 mm. In addition, by preparing the case main bodies 2 having different length dimensions, for example, up to 64 optical axis types having up to 64 optical elements, for example, 8 optical axes can be used in units of an arbitrary number of optical elements. , 12 optical axes, 16 optical axes, 20 optical axes,...
[0023]
FIG. 5 shows an optical system unit 40 built in the multi-optical axis photoelectric sensor 1. The optical system unit 40 has a plurality of element holders 41 arranged at equal intervals, and the element holder 41 has a cylindrical passage 42 formed therein. An optical element 43, that is, a light projecting element or a light receiving element is detachably fitted to the base end of the element holder portion 41, and the optical element 43 faces the cylindrical passage 42 through the first small circular opening 44. .
[0024]
At the front end of the element holder portion 41, a plastic lens plate 46 integrally formed with two adjacent light projecting or light receiving lenses 45 is arranged. For example, in the case of a light projector, light emitted from the light projecting element 43 is The light beam passes through the internal passage 42 having a circular cross section of the element holder portion 41 and then passes through the lens 45 to become a light beam which is a bundle of substantially parallel light beams. Conversely, in the case of a light receiver, the light beam is converged by the lens 45 and enters the light receiving element 43 through the first small circular opening 44.
[0025]
The optical system unit 40 is mainly made of a plastic molded product, and a single light shielding wall 47 is provided in the cylindrical internal passage 42. The light shielding wall 47 is integrally formed with the main body of the optical system unit 40. ing. A second relatively large circular opening 48 is formed in the center of the light shielding wall 47.
[0026]
The inner wall of the cylindrical internal passage 42 of the element holder 41 is preferably coated with a paint that can reduce the ability of the inner wall to reflect light, for example, a black paint. Needless to say, the pigment may be included in the plastic material of the main body of the optical system unit 40 so that the main body of the optical system unit 40 itself is darkened, such as black.
[0027]
The light shielding wall 47 is formed in the longitudinal direction, that is, in the middle part in the optical axis direction with respect to the cylindrical internal passage 42, so that one light shielding wall 47 can prevent malfunction due to stray light at a level that does not hinder practical use. It can be effectively prevented. The effect of this one light shielding wall 47 is as follows: (1) Since the amount of light regularly reflected a plurality of times by the wall of the internal passage 42 of the element holder portion 41 is attenuated, even if this light goes out, it is not affected. (2) It is assumed that the light diffusely reflected on the wall of the internal passage 42 of the element holder portion 41 has an attenuated amount of light, so that it is not affected even if it goes outside. In other words, the function of the light-shielding wall 47 of the internal passage 42 is, for example, in the case of a light projector, to prevent the light once specularly reflected by the wall 9 of the internal passage 42 from reaching the light projecting lens 45.
[0028]
Although the internal passage 42 of the optical system unit 40 of the embodiment has a cylindrical shape, if the internal passage 42 is tapered toward the lens 45 and has a circular cross-sectional shape, the light-shielding wall 47 is extended to the passage length of the internal passage 42. May be installed at a position closer to the lens 45 side than a half of the position. Conversely, if the internal passage 42 has a circular cross-sectional shape diverging toward the lens 45, a portion where the light shielding wall 47 is closer to the optical element 43 side than a half of the passage length of the internal passage 42. It should be installed in.
[0029]
The optical system unit 40 can be connected to an extension unit (not shown) at its end in accordance with the number of optical axes of the multi-optical axis photoelectric sensor 1. They have substantially the same structure.
[0030]
The optical system unit 40 includes, for example, a circuit board 49 disposed on the back side thereof and extending in the longitudinal direction along the unit 40. The circuit board 49 includes a power supply circuit, a control circuit, and a light emitting circuit (light receiving circuit). , A communication circuit and the like are incorporated. The relationship between the optical system unit 40 and the circuit board 49 will be described later.
[0031]
The optical system unit 40 including the circuit board 49 is inserted into the case main body 2 from one end opening of the case main body 2. As can be understood from FIG. 2, the case body 2 has a shape in which one side surface is open.
[0032]
The case body 2 is shorter than the entire length of the optical system unit 40 or the optical system unit 40 and the extension unit. More specifically, when the optical system unit 40 or the connected body of the optical system unit 40 and the extension unit is inserted, the case main body 2 includes two optical axes at both ends of the optical axes included in these units. The holder portion 41 is designed to protrude from the end of the case body 2 to the outside.
[0033]
Portions of the optical system unit 40 or the connected body of the optical system unit 40 and the extension unit that protrude outside from both ends of the case body 2 are surrounded by the end case 4 shown in FIGS. You.
[0034]
One end of the end case 4 is closed and the other end is open. The open end is connected to the case main body 2 by abutting the open end against the end of the case main body 2.
[0035]
The end case 4 has a flat front flange 50, and a slit 51 is formed in the front flange 50 on the open end side of the end case 4, and the slit 51 is a closed end of the end case 4. This slit 51 constitutes a window through which the light beam passes.
[0036]
The connection between the end case 4 and the case body 2 and the attachment of the front cover 5 will be described. The case body 2 has three screw receiving holes 52 opened at both ends of the case body 2 by three grooves extending in the longitudinal direction. (FIG. 2) is formed. Correspondingly, three holes 54 are formed in the end case 4 for inserting screws 53 (only the axis of the screws is shown in FIG. 6 to avoid complicating the drawing). The end case 4 and the case main body 2 are detachably screwed through a sealing gasket 56 in which a portion corresponding to the slit 51 is cut out, with the ends abutting each other.
[0037]
The cross member 7 described above is made of a metal plate material, and has a long flat main body 60 and a pair of left and right legs 61 hanging downward from both end edges of the main body 60. The projection 62 is formed by cutting and raising.
[0038]
The cross member 7 is disposed at the open end of the end case 4. To position the cross member 7, an opening 63 for receiving the leg 61 of the cross member 7 is provided in the end case 4. (FIG. 7) is formed, and the cross member 7 is snap-fitted into the opening 63.
[0039]
FIG. 8 shows the first front cover 5 and the second front cover 6. The first front cover 5 is slightly longer than the entire length of the case body 2, and the second front cover 6 is slightly shorter than the entire length of the end case 4. The first and second front covers 5, 6 are made of a light-transmitting plastic material.
[0040]
When attaching the first and second front covers 5 and 6, first, an adhesive sealant is continuously applied to the case body 2 and the end case 4. The sealant is applied continuously so as to cross. Next, the positioning is performed while pressing the first and second front covers 5 and 6. Thereby, the end of the first front cover 5 is located across the boundary between the case main body 2 and the end case 4, and then, when the cross member 7 is snap-fitted to the open end of the end case 4, The end of the first front cover 50 is pressed downward by the cross member 7, and both ends of the first front cover 50 are physically fixed by the cross member 7.
[0041]
FIG. 10 is a diagram related to the light projector 20, and FIG. 11 is a diagram related to the light receiver 30. Referring to FIG. 10 relating to light projector 20, light projector optical system unit 70 as optical system unit 40 described above includes a light projector circuit board 71 as circuit board 49 arranged along the back surface thereof. The floodlight circuit board 71 has a length extending substantially over the entire length of the floodlight optical system unit 70. Eight through holes or notches 74 through which two connection terminals 73 of the light emitting element 72 as the optical element 43 can pass are formed in a line at equal intervals on the light emitting circuit board 71. The light emitting element 72 has two connection terminals 73 protruding from the rear surface of the light emitting circuit board 71 through the through holes or notches 74, and the projecting ends of the connecting terminals 73 are connected to the light emitting circuit board 71. Soldered to the circuit.
[0042]
Referring to FIG. 11 relating to light receiver 30, optical system unit 75 for a light receiver as optical system unit 40 includes a light receiving control circuit board 76 as a circuit board 49 and a light receiving amplifier circuit board 77, and a light receiving control circuit board. Numeral 76 is located along the back of the optical system unit 76, and a light receiving amplifier circuit board 77 is arranged so as to be orthogonal to the light receiving control circuit board 76. That is, the light receiving control circuit board 76 and the light receiving amplifier circuit board 77 are arranged so as to be orthogonal to each other so as to form an L-shape. It has a length dimension that extends over substantially the entire length of the system unit 75.
[0043]
As can be understood from FIG. 11, the light receiving element 78 as the optical element 43 has a relatively flat rectangular parallelepiped outer shape, and two connection terminals 79 extend from the lower end surface thereof. The light receiving amplifier circuit board 77 is then formed with eight notches 80 along the side edge, through which the connection terminals 79 of the light receiving element 78 can penetrate, at equal intervals. The two connection terminals 79 penetrate the notch 80 and protrude from the lower surface of the light-receiving amplifier circuit board 77. The protruding ends of the connection terminals 79 are bent and soldered to the circuit of the light-receiving amplifier circuit board 77.
[0044]
10 and 11, reference numeral 81 denotes an internal connector that engages with the external connector 8 (FIG. 3). The internal connector 81 is attached to both ends of the light-transmitting circuit board 71 and the light-receiving control circuit board 76. As described above, the internal connector 81 is located facing the insertion port 10 of the end case 4 (FIG. 1).
[0045]
12 to 20 exemplarily show the optical system unit 70 for a light projector, but a light projector can be similarly applied to the optical system unit 75 for a light receiver.
[0046]
The optical unit 70 for a projector has a shield member 90. As shown in FIG. 13, the shield member 90 has a flat plate-shaped portion 91 extending along the unit 70 and in the longitudinal direction thereof, and a plurality of rectangular box-shaped portions 92. The periphery of the element holder 41 is surrounded. The material of the shield member 90 may be a magnetic shield material or an electromagnetic shield material as long as it is conductive. Reference numeral 94 shown in FIG. 12 indicates a hole for an indicator light having a built-in LED, and a plurality of the indicator light holes are arranged in a line at a central portion of the unit 70 in the longitudinal direction.
[0047]
An insulator 95, which is a molded product, is inserted into the end of the optical system unit for a projector 70 (FIG. 14), and then the end case 4 is inserted (FIGS. 17 and 18). As shown in FIGS. 15 and 16, the insulator 95 has a shape in which one end surface 96 is closed, and also has a shape in which the front surface 97 is opened to avoid interference with the optical axis. And a portion 99 extending along the wall of the recess 9 of the end case 4 (see also FIG. 19).
[0048]
When the insulator 95 is inserted into the end of the optical system unit for a projector 70, the closed end face 96 of the insulator 95 is interposed between the end of the unit 70 and the end face of the end case 4, and the circuit board 49 (71) is supported by the end case 4 via an insulator 95. That is, the insulator 95 is formed so as to support the circuit board 49 (71) and contact the inner surface of the end case 4.
[0049]
Therefore, the end of the circuit board 49 (71) is supported by the end case 4 via the insulator 95. As described above, the end of the circuit board 49 (71) is connected to the connector for connector connection. Since the internal connector 81 (FIGS. 10 and 11) to which an external force is applied is disposed, the direct support structure of the internal connector 81 can be secured by the insulator 95.
[0050]
According to the preferred embodiment of the present invention described above, the configuration is adopted in which the case main body 2 and the end case 4 are fastened using the screws 53 suitable for securing the fastening rigidity. Although the internal space of the metal end case 4 tends to be narrow, not only the end of the optical system unit 40 is surrounded by the insulator 95, but also the withstand voltage can be ensured. As can be best understood from FIG. 22, since the insulator 95 is interposed between the shield member 90 (92) surrounding the element holder 41 of the outermost optical axis and the end of the end case 4, The shield member 90 (92) surrounding the element holder 41 of the outermost optical axis and the end of the end case 4 can be extremely adjacent to each other, so that the outermost optical axis is multi-optical axis. It can be arranged near the end of the photoelectric sensor 1.
[0051]
The optical element 43 is arranged adjacent to the end of the end case 4, but an insulator 95 is interposed between the outermost optical element 43 and the end face of the end case 4. Therefore, even if the outermost optical element 43 and the end surface of the end case 4 are closer to each other than the pitch (20 mm or 14 mm) between the optical elements, the dielectric strength can be ensured by the insulator 95. The optical axis can be arranged adjacent to the end of the end case 4, so that the distance between the adjacent multi-optical axis photoelectric sensors 1 and 1 can be reduced to increase the optical axis density in the state where the light curtain is increased. Can be made.
[0052]
In particular, in the multi-optical axis photoelectric sensor 1 of the embodiment, since a recess 9 for receiving the external connector 8 is formed by cutting out a part of the end case 4, the end case 4 Since the internal space is small, it is preferable to surround the end of the optical system unit 40 with the insulator 95 to increase the withstand voltage in order to prevent malfunction of the multi-optical axis photoelectric sensor 1 which is a safety device. In addition, it is preferable to surround the portion where the optical element 43 is disposed with the magnetic shield member 90 in order to prevent the malfunction of the multi-optical axis photoelectric sensor 1.
[0053]
In addition, adopting the insulator 95 as a molded product can improve the assemblability of the operation of inserting the end of the optical system unit 40 and the operation of inserting the end case 4.
[0054]
Although the preferred embodiment of the present invention has been described above, the present invention is not limited to this, but includes the following modifications.
[0055]
The fastening method between the case main body 2 and the end case 4 is not limited to the screw 53, and a conventionally known fastening method may be adopted.
[0056]
When the optical element 43 (72, 78) is surrounded by the shield member 90, the shield member 90 and the walls of the case main body 2 and the end case 4 are closer to each other. It is preferable to provide an insulator in a portion surrounding 43. Here, the insulator may be any of a film, a tape, and an insulating resin molded product.
[0057]
The withstand voltage of the optical system unit 40 may be locally increased. In this case, it is preferable to use an insulating tape or an insulating film. Alternatively, it may be attached to the inner wall surface of the case body 2 or the end case 4, or an electrically insulating paint may be applied to the optical unit 40 and / or the inner wall surface of the case body 2 or the end case 4. May be applied.
[0058]
Further, the space between the optical system unit 40 and the case body 2 or the end case 4 may be filled with an electrically insulating filler such as epoxy resin.
[0059]
The drawings after FIG. 23 relate to a protective cover 100 which is convenient to apply to the multi-optical axis photoelectric sensor 1 having the above-described structure. Conventionally known protection covers include a type that surrounds the entire sensor and a type that is detachably attached to the front surface of the sensor. Therefore, when the plurality of multi-optical axis photoelectric sensors are installed in a straight line or an L-shape by bringing the ends of the plurality of multi-optical axis photoelectric sensors close to each other, the separation distance between adjacent multi-optical axis photoelectric sensors is increased. It was something to do.
[0060]
As described above, the multi-optical axis photoelectric sensor 1 of the present embodiment has the outermost optical element 43 and the end face of the multi-optical axis photoelectric sensor 1 by disposing the optical element 43 also in the end case 4. It is proposed to reduce the distance between the optical axes of the multi-optical axis photoelectric sensor 1 by reducing the distance between the optical axes. When a conventional protective cover is applied to such a multi-optical axis photoelectric sensor 1, the distance between the optical axes increases due to an increase in the outer dimensions of the multi-optical axis photoelectric sensor due to the presence of the protective cover. The advantage of the multi-optical axis photoelectric sensor 1 having a small distance disappears. The protective cover 100 illustrated in the drawings after FIG. 23 aims to solve the above-described problem.
[0061]
The protective cover 100 includes a frame 101 having an outer contour substantially the same as the front contour of the multi-optical axis photoelectric sensor 1, and a transparent protective sheet 102 adhered to the frame 101. The protective sheet 102 is detachable from the photoelectric sensor 1 and can be replaced with a new protective cover 100 when the protective sheet 102 is damaged.
[0062]
As can be understood from FIG. 24, the frame 101 made of plastic is constituted by two L-shaped frame end members 103 and two central frame members 104 extending straight, and these ends are connected to each other. A frame 101 having an elongated opening is formed by bonding.
[0063]
The frame end member 103 is a mold molded product having substantially the same length dimension as the end case 4 of the multi-optical axis photoelectric sensor 1. The center frame member 104 is an extruded product having substantially the same length dimension as the case main body 2 of the multi-optical axis photoelectric sensor 1. The center frame member 104 has a length dimension corresponding to the length dimension of the multi-optical axis photoelectric sensor 1 (for example, 8 optical axis type, 12 optical axis type, 16 optical axis type...). By preparing different central frame members 104, it is designed so that the frame body 101 applicable to each of the multi-optical axis photoelectric sensors 1 having different numbers of optical axes can be manufactured.
[0064]
The central frame member 104 has two grooves 105, 106 extending adjacent to each other and extending in a longitudinal direction, and has an arm 107 extending away from the grooves 105, 106. On the edge of the arm 107, a claw 108 is formed as a means for detachably engaging the protective cover 100 with the multi-optical axis photoelectric sensor 1.
[0065]
The frame end member 103 has two grooves 110 and 111 extending over the entire area thereof, and has an extension arm extending at a portion adjacent to the central frame member 104 so as to partially cover the end of the arm 107. 113 and an extension claw 114 aligned with the claw 108.
[0066]
Of the two grooves 105 and 106 of the central frame member 104, the first groove 105 located outside is continuous with the first groove 110 located outside the frame end member 103, and extends around the entire periphery of the frame body 101. An outer continuous groove extending over the entire surface is formed, and the peripheral edge of the protective sheet 102 is fixed in the continuous groove by an adhesive.
[0067]
Of the two grooves 105, 106 of the central frame member 104, the second groove 106 located inside is continuous with the second groove 111 located inside the frame end member 103, and extends all around the frame 101. An inner continuous groove extending therethrough is formed. The inner continuous groove can removably receive a light-transmissive additional sheet 116 at the user's option.
[0068]
The additional sheet 116 may be, for example, a polarizing sheet or a transparent protective sheet. The width of the inner continuous groove formed by the second grooves 106 and 111 of the center frame member 104 and the frame end member 103 is preferably set in consideration of the thickness of a general-purpose transparent sheet. Thus, the user obtains the relatively inexpensive additional light transmission sheet 116 and, for example, arranges the additional sheet 116 inside the main protection sheet 102 of the protection cover 100, thereby forming a double protection sheet. It can be used as a protective cover 100 provided.
[0069]
When the multi-optical axis photoelectric sensor 1 is used, for example, by the side of a sputtering apparatus, the multi-optical axis photoelectric sensor 1 is protected by the double cover. Therefore, a sense of security can be given to the user.
[0070]
When the protective cover 100 is mounted on the multi-optical axis photoelectric sensor 1, two grooves 120 (FIG. 26) formed in the case body 2 located at the center of the multi-optical axis photoelectric sensor 1 near the open ends of both side walls. ) Is used. Both ends of the two grooves 120 constitute screw receiving holes 52 for screwing the end case 4 to the case main body 2 described above.
[0071]
Specifically, when the protective cover 100 is mounted on the multi-optical axis photoelectric sensor 1, the two arms 107 of the central frame member 104 sandwich both side walls of the case main body 2, and the claws 108 engage with the grooves 120 of the case main body 2. Engage with corners. Similarly, the extension arm 113 of the frame end member 103 sandwiches both side walls of the end case 4, and the extension claw 114 engages with the recess of the end case 4 continuous with the groove 120 of the case main body 2. It has become. The engagement between the frame end member 103 and the end case 4 prevents the protective cover 100 from being displaced in the longitudinal direction of the multi-optical axis photoelectric sensor 1, and the protective cover 100 is substantially positioned.
[0072]
As described above, the protective cover 100 has the same width as the end of the multi-optical axis photoelectric sensor 1 and has a contour substantially flush with the end face of the multi-optical axis photoelectric sensor 1 (FIG. 28). ). Specifically, since the end surface of the end case 4 accommodating the optical axis located at the end of the multi-optical axis photoelectric sensor 1 has the same contour as the end face and both side walls (FIG. 29), the state in which the protective cover 100 is mounted is shown. However, the same inter-optical axis distance as in the state without the protective cover 100 can be ensured. This means that even if a plurality of multi-optical axis photoelectric sensors 1 are prepared and connected in a linear or L-shape, the distance between the optical axes between the multi-optical axis photoelectric sensors 1 and 1 is determined by the presence or absence of the protective cover 100. Can be kept regardless.
[0073]
In addition to the main protective sheet 102 adhered to the outside, the protective cover 100 can detachably attach an additional sheet 116 adjacent to the main protective sheet 102. If the protection sheet of the above is selected, it can be used as the protection cover 100 provided with a double protection sheet. In particular, by setting the width of the inner groove 106 for accommodating the additional sheet 116 to the thickness of the general-purpose sheet, a relatively inexpensive additional sheet can be provided for double protection.
[Brief description of the drawings]
FIG. 1 is a perspective view of a multi-optical axis photoelectric sensor according to an embodiment.
FIG. 2 is a front view of a case main body of the multi-optical axis photoelectric sensor according to the embodiment.
FIG. 3 is a partial diagram illustrating an end portion of the multi-optical axis photoelectric sensor according to the embodiment and illustrating a state where an external connector is connected.
FIG. 4 is a diagram illustrating an example in which the multi-optical axis photoelectric sensors according to the embodiment are connected to each other using a cable to form a light curtain in a wide range.
FIG. 5 is a sectional view of an optical system unit incorporated in the multi-optical axis photoelectric sensor according to the embodiment.
FIG. 6 is a perspective view of an end case of the multi-optical axis photoelectric sensor of the embodiment.
FIG. 7 is an exploded view of an end case and a member related to the cross member incorporated in the end case of the multi-optical axis photoelectric sensor of the embodiment and a seal member interposed between the end body and the case main body. It is an exploded perspective view.
FIG. 8 is a perspective view of a cross member.
FIG. 9 is a diagram for explaining that the front cover of the multi-optical axis photoelectric sensor includes a first front cover and second front covers disposed at both ends thereof.
FIG. 10 is an exploded view of an optical system unit and a circuit board incorporated in a light projector included in the multi-optical axis photoelectric sensor of the embodiment.
FIG. 11 is an exploded view of an optical system unit and a circuit board incorporated in a light receiver included in the multi-optical axis photoelectric sensor of the embodiment.
FIG. 12 is a perspective view showing a state where a shield member is mounted on the optical system unit.
FIG. 13 is a partial perspective view showing a part of a shield member employed in the embodiment.
FIG. 14 is a perspective view showing a state where an insulator, which is a molded product, is attached to an end of the optical system unit surrounded by a shield member.
FIG. 15 is a perspective view of an insulator.
FIG. 16 is a perspective view of the insulator viewed from another direction with reference to FIG. 15;
FIG. 17 is a view for explaining that an end case is inserted after an insulator is inserted into an end of an optical system unit surrounded by a shield member.
FIG. 18 is a view showing a state after the end case is inserted into the end of the optical system unit in relation to FIG. 17;
FIG. 19 is a sectional view taken along line X19-X19 in FIG. 18;
FIG. 20 is a diagram showing a state where an optical system unit is inserted into a case main body.
FIG. 21 is a cross-sectional view of an end of the multi-optical axis photoelectric sensor of the example.
22 is an enlarged cross-sectional view showing a part indicated by an arrow X22 in FIG.
FIG. 23 is a diagram showing a protective cover that can be conveniently applied to the multi-optical axis photoelectric sensor of the embodiment.
FIG. 24 is an exploded perspective view of a protective cover.
FIG. 25 is a sectional view of an end of the protective cover.
FIG. 26 is a view for explaining a pre-stage in which the protective cover is mounted on the multi-optical axis photoelectric sensor by cross-sectioning the central portion in the longitudinal direction of the protective cover.
FIG. 27 is a view related to FIG. 26 and is a cross-sectional view after a protective cover is attached to the multi-optical axis photoelectric sensor.
FIG. 28 is a side view of a multi-optical axis photoelectric sensor with a protective cover attached.
29 is a sectional view taken along line X29-X29 of FIG. 28.
[Explanation of symbols]
1 multi-optical axis photoelectric sensor
2 Case body
4 End case
9 Recess for receiving external connector
10 Insertion port to insert external connector
40 Optical system unit
41 Element holder
49 circuit board
81 Internal Connector
90 magnetic shield
95 insulator

Claims (7)

An optical system unit including an element holder portion that supports each of the plurality of optical elements and a circuit board, and arranging the optical elements in a line at an interval from one end to the other end;
A case body surrounding a central portion of the optical system unit;
An end case connected to an end of the case main body and surrounding an end of the optical system unit,
A multi-optical axis photoelectric sensor, wherein an insulator is interposed between the end case and the optical system unit. The multi-optical axis photoelectric sensor according to claim 1, wherein a cable extends laterally from the end case. The multi-optical axis photoelectric sensor according to claim 1, wherein the element holder of the optical system unit is surrounded by a shield member. The multi-optical axis photoelectric sensor according to any one of claims 1 to 3, wherein the insulator is locally provided between an end of the optical system unit and the end case. The multi-optical axis photoelectric sensor according to claim 4, wherein the insulator is provided between an end of the optical system unit and an end of the end case. The multi-optical axis photoelectric sensor according to claim 1, wherein the insulator is formed of a molded product. The multi-optical axis photoelectric sensor according to claim 6, wherein a circuit board included in the optical system unit is supported by the end case via the insulator.

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