JP2007157555A - Photoelectric sensor with multiple light axes - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photoelectric sensor with multiple light axes having a sealing structure excellent in reliability. <P>SOLUTION: A case covering optical units 40, 110 is into three parts of an end part case 130A, an intermediate case 35, and an end part case 130B. The intermediate case 35 is formed into cylindrical shape and the end part cases 130A, 130B are formed into is formed into bottomed cylinder shape with tightly closed peripheral wall, and a seal ring 170 is intercalated in fitting part of respective cases. By this constitution, whole part of the case divided into three can be fundamentally sealed by the seal ring 170 sealing a part between the end part case 130A and the intermediate case 35, and the seal ring 170 sealing a part between the intermediate case 35 and the end part case 130B. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a multi-optical axis photoelectric sensor.

  Conventionally, a light equipped with a projector (multi-optical axis photoelectric sensor) in which light projecting elements are arranged in a row in a case and a light receiver (multi-optical axis photoelectric sensor) in which light receiving elements are arranged in a row in a case Curtains are known. This projector and receiver are arranged opposite each other with a predetermined detection area so that each light projecting / receiving element forms a pair and forms an optical axis. Is to do. When an object is present in the detection region, light emitted from the projector and directed toward the light receiver is blocked, and the light reception level of the light receiver is lower than when no object is present. Thereby, it is possible to detect the presence or absence of a light-shielding object in the detection area.

  For such projectors and receivers, if water or the like enters the case from the outside, the optical units housed inside, that is, the photoelectric elements (light projecting elements, light receiving elements), lenses, and electronic components (electrical parts, etc.) will fail. (Deterioration) may occur. Therefore, various seal structures have been proposed for a case that houses the optical unit in order to protect the optical unit (for example, Patent Document 1).

In this case, as shown in FIG. 21, the case 1 has a cylindrical shape penetrating up and down, and the optical units 9A and 9B are accommodated from the shaft ends thereof. The lid members 3A and 3B are attached in a state where 4B is inserted. A pair of large windows (light emitting / receiving windows) 2A and 2B extending in the longitudinal direction of the case 1 are formed on the front surface 2 of the case 1 on the upper and lower sides, and the front surfaces corresponding to the large windows 2A and 2B. A pair of covers 5A and 5B are provided. Then, seal rings 6A and 6B having shapes corresponding to the opening shapes of the large windows 2A and 2B are inserted between the large window 2A and the front cover 5A and between the large window 2B and the front cover 5B, respectively. Therefore, the same part is sealed.
Japanese Patent Laid-Open No. 10-74432

In the above structure, four seal members 4A, 4B, 6A, and 6B are used to seal the entire case. As described above, when a large number of seal members 4A, 4B, 6A, and 6B are used, if any one of the seal members is defective, the seal is not sealed as a whole, so that the reliability of the seal is not sufficient. In particular, the seal between the large window 2 and the front cover 5 has the following problems. The front cover 5A, 5B surface and the front surface 2 of the case 1 where the large windows 2A, 2B are formed generally have some warpage. Moreover, the seal members 6A and 6B that seal the gap between them have a long seal length (the total length of the seal member). Accordingly, when the gap is sealed with the seal members 6A and 6B, the seal state is not uniform over the entire circumference of the seal length, and the seal tends to be partially insufficient.
The present invention has been completed based on the above circumstances, and an object thereof is to provide a multi-optical axis photoelectric sensor having a seal structure with excellent reliability.

  As means for achieving the above object, the invention of claim 1 is directed to an optical unit having photoelectric connection elements arranged in a line and having an electrical connection part for electrical connection to an end part, and the optical unit. At least one has a shape that is long in one direction that can be accommodated inside, and one end in the longitudinal direction opens as a connection port for performing the electrical connection with the other optical unit housed inside. A multi-optical axis comprising a pair of end cases and configured to accommodate the optical units in both end cases by fitting the connection ports of the end cases while accommodating the optical units therein A photoelectric sensor, wherein the end case is hermetically sealed in a sealed state except for the connection port, and a sealing member that seals between both ends is provided at a fitting portion where the end cases are fitted to each other. , Both ends When fitting the scan connection ports between, linked both ends casing has a feature where a structure to be sealed as a whole.

In addition, the following is preferable as the configuration of the end case.
The end case is made of a translucent resin material that allows light in the wavelength band of detection light, in which the photoelectric element forms an optical axis with the counterpart photoelectric element to perform detection operation. Alternatively, in the end case, the detection surface on which the photoelectric element forms the optical axis with the counterpart photoelectric element and performs the detection operation is a translucent resin material that transmits light in the wavelength band of the detection light, And the part which comprises the same detection surface is shape | molded integrally in the other part of an end case. By setting it as such a structure, the whole periphery except a connection port can be sealed in a sealed state, ensuring required optical penetration.

  According to a second aspect of the present invention, in the first aspect of the present invention, the optical unit is housed inside, and both ends of the cylindrical unit open as connection ports that allow electrical connection with the other of the optical unit. The translucent intermediate case is configured to be connected to each other by fitting the connection port of the intermediate case and the connection port of the end case to each other. When the sealing member is inserted and the end cases are connected to both ends of the intermediate case, the three cases are sealed as a whole.

  The invention of claim 3 is characterized in that, in the invention described in claim 2, the intermediate case is provided with a plurality of types having different overall lengths according to the number of connection stages of the optical unit.

  According to a fourth aspect of the invention, in the third aspect of the present invention, in the end case, one optical unit is fixedly accommodated, and the entire end case including the optical unit is the end unit. It has the characteristics where it is done.

  A fifth aspect of the present invention provides the connector according to any one of the first to fourth aspects, wherein the end case is provided with a connector connecting portion for electrical connection with the other, A connector that can be connected to a mating connector provided in an electric cable, and a connector sealing member is inserted in a fitting portion between the connector connecting portion and the mating connector so that a gap is sealed between the two. It has the characteristics where it is done.

  According to a sixth aspect of the invention, in the fifth aspect of the invention, there is provided condition changing means for changing the setting of a condition including at least a detection condition for the detection operation by the photoelectric element, and the condition changing means. Is provided at a portion of the connector connecting portion facing the mating connector, and is sealed by the connector sealing member when the mating connector is connected, whereas the mating connector is connected. It is characterized in that it is exposed when not, and the condition can be changed by an external operation.

  Note that the above detection condition includes a condition regarding the start timing of the scanning operation. That is, a light projecting side having a light projecting element as a photoelectric element and a light receiving side having a light receiving element as the photoelectric element are opposed so that the light projecting element and the light receiving element form a plurality of optical axes. In a multi-optical axis photoelectric sensor that detects the presence / absence of light shielding for each optical axis based on the received light signal output from each light receiving element, and sequentially activates the paired light projecting / receiving elements. One scan is performed until the activation is completed, and the start timing can be changed by the condition changing means of claim 6.

  A seventh aspect of the present invention is the optical unit according to any one of the first to sixth aspects, wherein the end of the optical unit where the electrical connection portion is provided is along the connecting direction of the optical unit. While the extending one arm is provided, the optical unit on the other side which is the other side is provided with a guide portion extending in the longitudinal direction of the arm at a position facing the arm, and the connecting operation of both optical units is performed. It is characterized in that it is guided by the fitting of the arm and guide part.

  The invention according to claim 8 is the light emitting device according to claim 7, wherein a light projecting side having a light projecting element as the photoelectric element and a light receiving side having a light receiving element as the photoelectric element are provided. In a multi-optical axis photoelectric sensor arranged so as to face each other so as to form a plurality of optical axes, at least one of the arrangement and shape of the arm and the guide unit is changed between the light projecting side and the light receiving side. It has features in some places.

  According to a ninth aspect of the present invention, the optical unit according to any one of the second to eighth aspects is accommodated in the intermediate case in a state of being fixed to a unit case having a cylindrical shape. The unit case is characterized in that a support protrusion is provided to contact the case inner wall of the intermediate case.

  The invention of claim 10 is characterized in that, in the invention of claim 9, the unit case is a shield case made of metal.

  According to an eleventh aspect of the present invention, in any one of the first to tenth aspects, the outer periphery of the intermediate case and the end case is of a size that allows a light projecting / receiving operation by the photoelectric element. It is characterized in that it is covered with a metal protective case having an optical insertion window.

<Invention of Claim 1>
According to the first aspect of the present invention, the case covering the optical unit is divided and configured by the pair of end cases, and each of the divided end cases has a sealed structure in which the entire circumference except the connection port is sealed. . And it was set as the structure which accommodates an optical unit in an inside, connecting both cases by fitting the connection ports of both ends case. If it is such a structure, if a sealing member is inserted in the fitting part by which edge part cases are fitted, the whole case can be sealed with a single sealing member. Therefore, the number of seal members necessary to seal the entire case can be reduced as compared with the conventional seal structure.
Moreover, since the end case has a sealed structure, it is not necessary to take a seal along the longitudinal direction of the end case. In other words, since the seal length itself can be shortened as compared with the conventional structure, the reliability of the sealing effect is increased.

<Invention of Claim 2>
According to the invention of claim 2, since both ends of the intermediate case are open, the optical unit of the intermediate case can be electrically connected to the optical unit of the end case through the opening. Further, when the end cases are connected to the both ends of the intermediate case, the three cases are sealed as a whole by the seal member inserted between the two (fitting portions). With such a configuration, the number of sealing members necessary to seal the entire case is only two at both ends regardless of the total length of the intermediate case. Therefore, a suitable configuration is obtained when the optical units are connected in multiple stages and the total length of the case becomes long. In addition, the same sealing effect can be obtained by increasing the total length of both end cases without using an intermediate case, but the intermediate case is less expensive to manufacture than the end case (because it is a simple cylinder) ) Excellent in cost.

<Invention of Claim 3>
According to the invention of claim 3, the intermediate case is provided with a plurality of types having different overall lengths. With such a configuration, if the number of connection stages of the optical unit is different, the intermediate case may be selectively used accordingly. Therefore, the cost can be reduced as compared with the case where all the parts are provided exclusively according to the number of connection stages of the optical unit.

<Invention of Claim 4>
According to the invention of claim 4, one optical unit is fixedly accommodated in the end case, and the entire end case including the optical unit is the end unit. Such a configuration is excellent in terms of component management.

<Invention of Claim 5>
According to the invention of claim 5, the space between the connector connecting portion and the mating connector is also sealed. Therefore, the sealing performance as the whole apparatus is further enhanced.

<Invention of Claim 6>
According to the invention of claim 6, since the seal of the condition changing means is also used as the seal of the connector, the number of parts can be reduced accordingly. Also, if the mating connector is removed, the condition changing means is exposed, so the conditions can be changed easily.

<Invention of Claim 7>
According to the invention of claim 7, when the arm is fitted to the guide portion and the optical units are brought closer to each other from the state, the optical unit is guided by the fitting of the arm and the guide portion so that the optical units face each other. The electrical connection portions of the optical unit are connected to each other. In this manner, the optical unit can be approached with the optical unit facing directly by fitting the arm and the guide portion, so that the optical unit can be easily connected.

<Invention of Claim 8>
According to invention of Claim 8, arrangement | positioning of an arm and a guide part is changed with the light projection side and the light-receiving side. Therefore, even if the light projecting side optical unit and the light receiving side optical unit are assembled, the fitting protrusion does not fit into the guide groove. Thereby, the incorrect assembly of the optical unit can be avoided beforehand.

<Invention of Claim 9>
According to the ninth aspect of the present invention, when the unit case is housed in the intermediate case, the support protrusion of the unit case comes into contact with the inner wall of the intermediate case. As a result, it is possible to prevent the unit case relative to the intermediate case, and hence the optical unit, from rattling.

<Invention of Claim 10>
According to the invention of claim 10, since the photoelectric element and the electrical component can be shielded electrostatically, the malfunction of the apparatus due to noise entering from the outside can be avoided in advance. Further, since the shield case is also used as the unit case, the configuration is simplified.

<Invention of Claim 11>
According to the invention of claim 11, since the protective case is provided on the outer periphery of the intermediate case and the end case, the optical unit can be effectively protected against an impact from the outside.

An embodiment of the present invention will be described with reference to FIGS.
<Light curtain detection principle>
FIG. 1 is a diagram illustrating an external configuration of a light curtain. As shown in the figure, the light projector (multi-optical axis photoelectric sensor of the present invention) S1 has light projecting elements (corresponding to the photoelectric elements of the present invention) arranged in a line in a casing. On the other hand, the light receiver (corresponding to the multi-optical axis photoelectric sensor of the present invention) S2 has light receiving elements (corresponding to the photoelectric elements of the present invention) arranged in a line in a casing. The light projector S1 and the light receiver S2 are arranged opposite to each other with a predetermined detection region so that each light projecting element and the light receiving element form a pair and form an optical axis L, and each optical axis L is sequentially activated. In other words, the presence / absence of a light-shielding object is detected by performing a light projecting / receiving operation (corresponding to the detection operation of the present invention).

  During detection, for example, the optical axes are sequentially enabled in the order of L2, L3,... From the lower optical axis L1 shown in FIG. A cycle until the activation of the upper optical axis L14 is completed is one scan, and this one scan operation is repeatedly performed by a scan start command from a control unit (not shown).

  When an object is present in the detection region, the light of the specific optical axis L emitted from the projector S1 and directed to the light receiver S2 is blocked, and the light receiving level of the light receiving element is compared with that in the optical axis L when no object is present. Will drop. Thereby, it is possible to detect the presence or absence of a light-shielding object in the detection area. Hereinafter, a specific configuration (mechanistic mechanism) of the light curtain will be described. However, since the configurations of the projector S1 and the light receiver S2 are basically the same, the light receiver S2 will be described as an example.

<Whole structure of light receiver S2>
2 is a perspective view of the light receiver S2, and FIG. 3 is an exploded perspective view of the light receiver S2.
The light receiver S2 mainly includes a detection device main body 30 having a shape that is long in one direction and a protective case 20 that covers the outer periphery of the detection device main body 30 and protects the detection device main body 30. The protective case 20 is made of metal, and the upper surface side in FIG. 3 has a substantially C-shaped cross section that opens as the light insertion window 21, and metal end plates 210A and 210B are screwed to both ends. It has become. In this way, the structure surrounding the detection device main body 30 with metal is a structure that is resistant to external impact (see also FIGS. 14 and 15).

<Configuration of Detection Device Main Body 30>
FIG. 4 is an exploded perspective view of the detection device main body 30. The detection device main body 30 is divided into three parts. That is, it is comprised from the intermediate part which consists of the intermediate | middle case 35 and optical unit 40A, 40B, and a pair of edge part unit 100A, 100B connected with the both ends.

First, the structure of the optical unit 40 alone will be described.
FIG. 5 is a side view of the optical unit, and FIG. 6 is a plan view of the optical unit. As shown in FIGS. 5 and 6, the optical unit 40 as a whole has a shape that is long in one direction (the left-right direction in the figure) and is entirely made of a metal shield case (corresponding to the unit case of the present invention) 50. Covered by. The shield case 50 includes an upper shield case 51 and a lower shield case 55. The upper shield case 51 has a U-shaped cross-sectional shape opening downward in the figure, while the lower shield case 55 has a U-shaped cross-sectional shape opening upward in the figure.

  When the shield cases 51 and 55 face each other, they can be fixed by the lock portion 59. The lock portions 59 are provided at both ends in the length direction (the left-right direction in FIG. 5) and at the center. Reference numeral 54 shown in FIG. 5 is a stopper that functions when the shield cases 51 and 55 are fixed to each other (if the assembly position is exceeded, the upper end surface 58 of the side wall of the lower shield case 55 is contacted). The position is regulated so that the two cases do not approach each other in the vertical direction in FIG. 5).

  Also, as shown in FIG. 5, support protrusions 53 are provided on the side wall of the upper shield case 51 at positions close to the left end and right end, respectively, and are also shown on the bottom surface of the lower shield case 55. A support protrusion 57 is provided so as to bulge downward. The support protrusions 53 and 57 will be described later, but when the optical unit 40 is accommodated in the intermediate case 35, the optical units 40 </ b> A and 40 </ b> B in the case come into contact with the inner wall of the intermediate case 35. It is something to regulate.

  A male electrical connection 61 is provided at the left end of the optical unit 40, and a pair of arms 65 is provided above it. On the other hand, a female electrical connection 71 is provided at the right end of the optical unit 40, and a guide 75 corresponding to the arm 65 is provided above the female electrical connection 71.

  FIG. 7 is a view of the optical unit as seen from the direction A in FIG. The male-side electrical connection portion 61 includes two upper and lower connection pins 63 on a block-like base portion 62 and six rows in the width direction (left-right direction in the figure). As shown in FIG. 6, these connection pins 63 protrude horizontally from the front end surface of the base 62 along the longitudinal direction of the optical unit 40. The arm 65 is in a region above the base portion 62, has a prismatic shape, and is provided horizontally along the longitudinal direction of the optical unit 40 like the connection pin 63. Further, as shown in FIG. 7, guide grooves 67 and 68 are provided on the inner surfaces of both arms 65, respectively. The guide grooves 67 and 68 are also provided along the longitudinal direction of the optical unit 40.

  FIG. 8 is a view of the optical unit as seen from the direction B in FIG. The female-side electrical connection portion 71 has a base portion 72 that has a block shape like the male-side electrical connection portion 61. The base 72 is provided with receiving ports 73 at positions facing the connection pins 63.

  A guide portion 75 is provided in a region above the base portion 72 and at a position corresponding to the previous arm 65. The guide portion 75 has a prismatic shape extending in the longitudinal direction of the optical unit 40. The width of the guide portion 75 (the width in the left-right direction in FIG. 8) is set somewhat narrower than the facing distance between the arms 65. Then, on the outer wall surface (left and right side surfaces in FIG. 8) of the guide portion 75, fitting projections 77 and 78 are provided along the longitudinal direction of the optical unit 40 so as to protrude outward. The fitting protrusions 77 and 78 are fitted into the guide grooves 67 and 68 described above.

  Thus, each optical unit 40 includes the male electrical connection 61 on one side and the female electrical connection 71 on the other side, so that the optical units 40A and 40B can be interconnected. That is, as shown in FIG. 9, the female side of one optical unit 40B is opposed to the female side of the other optical unit 40A, and first, the guide portion 75 of the optical unit 40A is fitted between the arms 65 of the optical unit 40B. I'll do it together. More specifically, the fitting protrusion 77 is fitted into the guide groove 67, and similarly, the fitting protrusion 78 is fitted into the guide groove 68.

  After the fitting, the connecting operation of both the units 40A and 40B is guided by the fitting of the guide groove 67 and the fitting protrusion 77 and the guide groove 68 and the fitting protrusion 78. 40A and 40B approach while maintaining the state of facing each other, and eventually the base portions 62 and 72 of both optical units 40A and 40B abut against each other. At this time, the female connection pin 63 enters the receiving port 73 of the female base 72 and is connected to a terminal fitting (not shown) provided in the female base 72. Thereby, both optical units 40A and 40B are electrically connected. Thus, the number of optical axes can be variously changed by connecting the optical units 40 to each other.

  Moreover, the code | symbol 81 in FIG. 9 is a coupling holder. The coupling holder 81 includes a pair of coupling pieces 83. When the optical units 40A and 40B are connected to each other, the lock claw provided at the tip of the coupling piece 83 is elastically locked to the other optical unit (in this case, 40B) and maintains the above-described electrical connection state. It is supposed to be.

  Further, when the optical units 40A and 40B are connected, the front end portion of the female guide portion 75 just abuts against the base end portion 66 of the arm 65. A damper (not shown) is inserted. By adopting such a configuration, the following effects can be obtained. In other words, when a change occurs in room temperature, etc., the resin parts will stretch, so the effect will also appear on the connection part, but the connection state between the optical units will be balanced so that it does not concentrate at a specific location. I can take it.

  In the present embodiment, as shown in FIGS. 7 and 8, the fitting protrusions 77 and 78 and the groove widths of the guide grooves 67 and 68 are changed on the left and right. Referring to FIG. 7, the groove width (a dimension portion) of the left guide groove 67 is wide, whereas the groove width (b dimension portion) of the right guide groove 67 is narrow. is there. As for the fitting protrusion, the fitting protrusion 77 corresponding to the guide groove 67 has a large protrusion width, while the fitting protrusion 78 corresponding to the guide groove 68 has a narrow protrusion width. In this way, the fitting pattern is changed on the left and right, even if the light emitting side and the light receiving side are mixed and assembled, so that they cannot be fitted, thereby preventing such erroneous assembly. Because.

  This is because the optical unit 40 on the light emitting side and the optical unit 40 on the light receiving side are the same in appearance, and are difficult to distinguish. In this case, if the fitting pattern of the arm 65 and the guide portion 75 is the same on the left and right, the fitting pattern is the same on the light projecting side optical unit 40 and the light receiving side optical unit 40. If they are fitted to each other, they will fit each other.

  Therefore, in this embodiment, in order to change the fitting pattern between the light projecting side and the light receiving side, the fitting pattern of the arm 65 and the guide portion 75 is changed on the left and right sides, and this is reversed between the light projecting side and the light receiving side. It is set. With such a configuration, even if the light projecting side optical unit 40 is connected to the light receiving side optical unit 40, the fitting protrusions 77 and 78 do not fit into the guide grooves 67 and 68, so that the wrong state remains. Thus, it is possible to avoid mechanical assembly. Here, “the light projecting side and the light receiving side are set oppositely” means that the left guide groove 67 has a wide groove width (a dimension portion) on the light receiving side. Since the groove width (b dimension portion) of the right guide groove is narrow, on the light emitting side, the groove width (a dimension portion) of the left guide groove 67 is formed narrow, and the right guide groove This means that the groove width (b dimension portion) is wide.

  Next, the internal structure of each optical unit 40 will be described. 10 is a cross-sectional view taken along the line CC in FIG. As shown in the figure, a circuit board 41, a light receiving element 43, a lens 45, a lens holder 47, and the like are housed in the shield case 50. The light receiving element 43 is arranged on the circuit board 41 with the light receiving surface facing upward in the figure, and a lens 45 is fixed above the light receiving element 43 so as to be abutted against the ceiling wall of the shield case 55. Yes.

  The holding structure of the lens 45 and the light receiving element 43 will be briefly described. The lens holder 47 is provided with a mortar-shaped lens holding portion 48, and the upper end portion of the lens holding portion 48 holds the outer edge of the lens 45. On the other hand, the light receiving element 43 is fitted to the lower end portion of the lens holding portion 48, and the lens 45 and the light receiving element 43 are held in an aligned state.

  Each of the circuit board 41 and the lens holder 47 has a shape extending in the horizontal direction of FIGS. 5 and 6, and the light receiving elements 43 are arranged on the circuit board 41 in a line along the longitudinal direction. Is done. On the other hand, the lens holder 47 is also provided with lens holding portions 48 at the same interval as the arrangement of the light receiving elements 43 so that all the light receiving elements 43 and the lenses 45 are held in a positioned state.

  The male and female electrical connection portions 61 and 71 described above are provided at both ends (longitudinal ends) of the circuit board 41, respectively, and the arms described above are provided at both ends of the lens holder 47. 65 and a guide portion 75 are provided. As shown in FIGS. 5 and 6, a light receiving window 52 is opened on the upper wall of the upper shield case 51 at a position facing each light receiving element 43.

  As shown in FIG. 10, the shield case 50 is formed with three support protrusions 53 and 57 as a whole on the same cross section. That is, two are provided in the upper shield case 51 and one is provided in the lower shield case 55. The support protrusion 53 of the upper shield case 51 is formed by projecting outward the portions near the upper ends of the left and right side walls, and the support projection 57 of the lower shield case 55 is formed by projecting the center portion of the bottom wall downward. Has been. The launch surfaces of the support protrusions 53 and 57 are flat flat surfaces 53A and 57A.

  Next, the intermediate case 35 will be described with reference to FIG. The intermediate case 35 is made of a transparent resin material and has a cylindrical shape in which both axial ends open as connection ports 35A and 35B. A plurality of intermediate cases 35 having the same cross-sectional shape and different only in overall length are provided. More specifically, a plurality of types having different total lengths are prepared in advance according to the number of optical units 40 accommodated therein.

  Here, since the optical units 40A and 40B connected in two stages to the case are accommodated, the intermediate case 35 having a two-stage length is selected in advance. That is, when the optical units 40A and 40B are inserted into the intermediate case 35 from the opening at the shaft end, the male electrical connection portion 61 of the optical unit 40A faces the connection port 35A on the near side in FIG. The female-side electrical connection portion 71 of the optical unit 40B faces the connection port 35B, and can be connected to end unit 100A, 100B described below. Further, at the time of insertion, the support protrusions 53 and 57 of the optical units 40A and 40B hit three points on the inner wall of the intermediate case 35, and rattling is restricted with respect to the surface direction along the paper surface in FIG. It is configured.

  Next, the end unit 100 will be described. In the present embodiment, the end unit 100 is provided with a pair of a female side end unit 100A and a male side end unit 100B. The female side end unit 100A on the left front side will be described as a representative.

  The female side end unit 100A is configured by housing the optical unit 110 in the end case 130A. Although not shown in detail, the end case 130A is provided with a locking means, which prevents the optical unit 110 from being detached in a non-removable state.

  The configuration of the optical unit 110 is basically the same as the configuration of the optical unit 40 inserted in the intermediate case 35 described above, and as shown in FIG. 11, a lens holder provided above the circuit board 111. The lens 115 and the light receiving element 113 are held while being positioned by 117.

  Further, the shield structure of the optical unit 110 is somewhat different from that on the intermediate case 35 side. That is, in the optical unit 40 on the intermediate case 35 side, the entire optical unit 40 is surrounded by the shield case 55, but on the end case 130A side, the shield case is abolished. A lower shield plate 121 is provided at the lower portion of the optical unit 110, and a side shield plate 123 is provided on the right side of the optical unit 110. Further, although no side shield plate is provided on the left side of the optical unit 110, the lens holder 117 is made of conductive resin and has a shielding function. Note that the end case 130 </ b> A may have a structure in which the entire case is covered with the shield case 50, similarly to the shield structure of the intermediate case 35.

  Next, the end case 130 </ b> A includes an upper end case 131 and a lower end case 151. The upper end case 131 has a U shape whose cross section is opened downward. On the other hand, the lower end case 151 has a U shape whose cross section is opened upward. And when both cases 131 and 151 face each other, it is comprised so that the optical unit 110 can be accommodated in an inside.

  As shown in FIG. 12, a connecting shaft portion 160 extending in the longitudinal direction of the end case 130A is formed at the shaft end portion on the right back side of the end case 130A. The connecting shaft portion 160 has a cross-sectional shape that follows the inner periphery of the intermediate case 35 and can be fitted into the connection port 35 </ b> A of the intermediate case 35. In addition, a pair of holding pieces 161 and 163 projecting outward are provided in the longitudinal direction of the end case 130 at a position near the tip of the connecting shaft portion 160. The holding pieces 161 and 163 are formed over the entire circumference of the connecting shaft portion 160, and an annular rubber seal ring (corresponding to a seal member of the present invention) 170 is disposed between the holding pieces 161 and 163. It is like that.

  The distal end of the connecting shaft portion 160 is opened as an electrical connection port (corresponding to the connection port of the present invention) 160A. A female-side electrical connection portion 127 provided at an end portion of the circuit board 111 accommodated in the end case 130 faces the electrical connection port 160A, and is electrically connected to the other through the electrical connection port 160A. Connection can be made (see FIG. 13). Although not shown in detail, the end units 100A and 100B are also provided with an arm 65 or a guide portion 75 in addition to the male and female electrical connection portions, and are used for electrical connection. , Designed to fulfill the guide function.

  Returning again to FIG. 12, the end case 130A, which is opposite to the electrical connection port 160A, is provided with a bottom plate 168 and closed. And in the end case 130, the joint part (for example, D part in FIG. 11) of the upper end case 131 and the lower end case 151 is hermetically sealed by ultrasonic welding over the entire length and the entire circumference. Yes. As a result, the end case 130 has one end opened as an electrical connection port 160A, whereas the end opposite to the end case 130 is closed by the bottom plate 168 and the mating portion is brought into close contact with each other. Except for the connection port 160A (in detail, except for a communication hole 181 to be described later), the entire circumference forms a bottomed cylindrical shape that is sealed when parts are processed. The above configuration corresponds to “the end case is sealed in a sealed state except for the connection port” in the present invention.

  Further, the end cases 130A and 130B are made of a resin material that transmits light in the wavelength band emitted from the light projecting element, and are configured so as not to hinder the light projecting / receiving operation by the light projecting element and the light receiving element. ing.

<Assembly of detection device main body 30 and seal structure>
Here, the assembly procedure of the detection device main body 30 configured as described above will be described, and the seal structure of the detection device main body 30 will be described together with this. As shown in FIGS. 4 and 12, in order to assemble the detection device main body 30, first, the optical units 40A and 40B are connected to each other. Then, the optical units 40A and 40B in the connected state are inserted through the connection port at the shaft end of the intermediate case 35, for example, the connection port 35A. When the housing of the optical units 40A and 40B is completed, the female end unit 100A and the male end unit 100B are connected (coupled) to the connection ports 35A and 35B of the intermediate case 35, respectively.

  For this purpose, the electrical connection portion 61 of the intermediate case 35 and the electrical connection portion 127 of the female end unit 100A are opposed to each other, and the both portions 61 and 127 are brought close to each other so as to face each other. Then, as shown in FIG. 13, the connecting shaft portion 160 of the female end unit 100A enters the inside through the connection port 35A of the intermediate case 35, and the electric connecting portion 127 and the intermediate case of the female end unit 100A. The 35 electrical connection portions 61 are electrically connected. As described above, the connecting operation is guided by the fitting of the guide portion 75 and the arm 66 (not shown).

  At this time, as shown in FIG. 13, the seal ring 170 attached to the tip of the connecting shaft portion 160 is pressed between the inner wall of the intermediate case 35 and the outer surface wall of the connecting shaft portion 160. As a result, the seal ring 170 uniformly adheres to both the inner wall of the intermediate case 35 and the outer wall of the connecting shaft portion 160 (more specifically, uniformly adheres over the entire circumference of the connecting portion). The space between both ends (the fitting portion between the end case 130A and the intermediate case 35) is sealed without a gap.

  When the connecting operation is also performed on the intermediate case 35 and the male end unit 100B, all the optical units 40A, 40B, 110 of the detection device main body 30 are electrically connected to each other, and the intermediate case 35 and the female end are connected. In addition to the fitting portion (E1 portion in FIG. 3) of the unit unit 100A, the fitting portion (E2 portion in FIG. 3) of the intermediate case 35 and the male side end unit 100B is sealed by the previous sealing structure. The detection device main body 30 is sealed as a whole.

  When the assembly of the detection device main body 30 is completed, as shown in FIG. 3, the protection case 20 is assembled to the detection device main body 30 (the end of the detection device main body 30 is attached to the end of the protection case 20). The detection device main body 30 may be inserted into the protective case 20 while the protective plate 20 is applied, and then the end plates 210A and 210B are respectively fixed to both ends of the protective case 20 in the axial direction. In contrast, the detection device main body 30 can be prevented from coming off.

  As shown in FIG. 3, both end portions 22 and 24 in the longitudinal direction of the protective case 20 are notched, and the outer peripheral walls of the end cases 130A and 130B are exposed there. Has been. The exposed portion is used as a connector connecting portion 180, and a power connector (a mating connector according to the present invention) 250 connected with a power cable (electric cable according to the present invention) 260 is attached.

<Power cable connection structure>
FIG. 16 is an exploded perspective view showing the connection structure of the power cable. As shown in the figure, the connector connecting portion 180 is formed by recessing the upper surface of the end case 130A within a predetermined length range from the rear end (range indicated by the dimension J shown in FIG. 16). ing. FIG. 17 is a plan view of the connector connecting portion 180. The connecting portion 180 is provided with a cable insertion hole 186 and a connector mounting seat portion 180A arranged side by side, and a screw seat having screw holes on both sides thereof. Portions 185 and 188 are provided.

  When the connector connecting portion 180 is viewed from the mounting operation direction of the power cable 260 (the direction orthogonal to the paper surface in FIG. 17), all three directions (shown by hatching) except the upper side in FIG. It is covered with the walls 182, 183, and 215 so that the posture of the power connector 250 is not inclined during the mounting operation. The three vertical walls 182, 183, and 215 will be described. The vertical walls 182 and 183 are configured by the wall surface of the end case 130 </ b> A that is recessed to form the connector connecting portion 180. On the other hand, the vertical wall 215 uses the wall surface of the end plate 210 </ b> A attached to the end of the protective case 20.

  A laterally long communication hole 181 opens at the center of the connector mounting seat 180A. As shown in FIG. 18, the communication hole 181 communicates the upper end case 131 vertically and communicates with the internal space of the end case 130A.

  A power supply terminal 193 and an adjustment switch (corresponding to the condition changing means of the present invention) 195 are provided side by side in FIG. 18 at a position inside the end case 130A and facing the communication hole 181. ing. The power supply terminals 193 are provided vertically so as to vertically penetrate through holes provided in the circuit board 11, and this embodiment has five rows in the longitudinal direction of the end case 130A and two steps in the front and rear. Has been. Reference numeral 192 shown in the figure is an alignment plate for maintaining the upright posture of the power terminal 193. The adjustment switch 195 has a slit 195A on the upper surface, and a jig such as a flat-blade screwdriver is inserted into the slit 195A to rotate it. It can be changed.

  Next, the power connector 250 will be described. The power connector 250 includes a horizontally long body portion 251 that follows the shape of the connector connecting portion 180. As shown in FIG. 16, screw seats 253 and 254 having screw insertion holes are provided on both sides of the main body 251. The three outer surfaces of the main body 251, that is, the inner surface 251 </ b> A in FIG. 16 and the end surfaces 253 </ b> A and 254 </ b> A of the screw seats 253 and 254 are flat and smooth surfaces. The vertical walls 182, 183, and 215 are set to be fitted with a minimum gap.

  A joint portion 257 that can be inserted into the communication hole 181 is provided on the lower surface of the main body 251 at a position facing the communication hole 181. Each joint portion 257 is provided with a terminal insertion hole 258 at a position facing the power supply terminal 193. Further, a cable lead-out portion 259 is provided along with the joint portion 257, and the power cable 260 is drawn out therefrom.

  Reference numeral 270 in FIG. 16 denotes a connector seal ring (corresponding to the connector seal member of the present invention). The connector seal ring 270 has a horizontally long shape in which the outer shape of the communication hole 181 is made slightly larger. The cross-sectional shape of the connector seal ring 270 is as shown in FIG. 18. The connector seal ring 270 is formed in a convex shape, and a lower half is provided with a half-moon contact edge 271. On the other hand, a receiving portion 252 following the shape of the connector seal ring 270 is provided on the lower surface of the power connector 250 at a position facing the connector seal ring 270.

  In order to assemble the power connector 250 described above to the connector connecting portion 180, first, the connector seal ring 270 is fitted into the receiving portion 252 of the power connector 250. Then, the joint portion 257 and the power cable 260 are set downward above the connector connecting portion 180, and the outer surface of the power connector 250 is addressed to each vertical wall of the connector connecting portion 180 from that state. I will do it. That is, the outer side surface 254A of the power connector 250 is addressed to the vertical wall 215 of the connector connecting portion 180, and the outer side surface 253B of the power connector 250 is addressed to the vertical wall 182 of the connector connecting portion 180. Then, the outer surface 251 </ b> A of the power connector 250 is applied to the vertical wall 183 of the connector connecting portion 180.

  After that, as shown in FIG. 18, if the power connector 250 is pushed downward toward the connector connecting portion 180, the power supply connector 250 is fitted into the vertical walls 182, 183, 215 and the outer surfaces 253 A, 251 A, 254 A. The whole 250 is accommodated in the connector connecting portion 180 while maintaining a posture facing the connector connecting portion 180. At this time, as shown in FIG. 19, the joint portion 257 enters the internal space of the end case 130 </ b> A through the communication hole 181, and each power supply terminal 193 enters the terminal insertion hole 258 provided in the joint portion 257. Thus, electrical connection between the two is achieved. Further, the power cable 260 is drawn out downward from the cable insertion hole 186 as shown in FIG.

  Then, the power connector 250 can be fixed to the connector connecting portion 180 by screwing the left and right portions by an operation from above in the figure. In addition, at this time, the connector seal ring 270 is pressed between the connector mounting seat portion 180 </ b> A and the lower surface of the main body portion 251. More specifically, the contact edge 271 of the connector seal ring 270 is pressed. As a result, the connector seal ring 270 is in close contact with both the power connector 250 and the connector connecting portion 180 without any gap, so that the gap between both is sealed over the entire circumference (the entire circumference surrounding the communication hole 181).

  As described above, the connector connecting portion 180 is provided with the three vertical walls 182, 183, and 215 that guide the outer surfaces 253 A, 251 A, and 254 A of the power connector 250. Holds the posture so as not to tilt. If the power connector 250 is assembled while the power connector 250 is tilted, the power terminal 193 does not enter the terminal insertion hole 258 of the joint portion 257 well and may be damaged in some cases. Thus, such a situation can be avoided and the power connector 250 can be assembled smoothly.

  Further, since the adjustment switch 195 is sealed together with the power terminal 193 by the connector seal ring 270, the upper surface cannot be operated when the power connector 250 is assembled. It is exposed by removing and can be changed by external operation.

  As shown in FIG. 17, the vertical wall 182 of the connector connecting portion 180 has a flat shape as a whole, whereas the vertical wall 215 opposed to this has a tip 216 formed in an arc shape. On the other hand, the corresponding portion of the power connector 250 also has a flat shape on the 253A side, whereas the tip 255 is formed in an arc shape on the 254A side. Thus, the following effects are acquired by making the shape which guides the power connector 250 into left-right asymmetric.

  As shown in FIG. 20, the light curtain may be connected in multiple stages by connecting the light projectors S1 and the light receivers S2 in series. Accordingly, in the present embodiment, the connector connector 180 described above is provided on each of the left and right sides of the detection device main body 30 (see FIG. 3). In this case, in FIG. 20, the power supply cable 260 is connected to the connector connecting portion 180 located on the left side of the master unit that is directly supplied with power from the power supply, whereas the connector connecting portion 180 on the right side is connected. The unit connection cable 290 is connected.

  Here, as described above, if the shape for guiding the connector is left-right asymmetric, the guide will not fit into the place where the unit connection cable 290 is erroneously connected to the place where the power cable 260 is originally connected. As a result, it is possible to avoid erroneous assembly of the cable. Needless to say, even when the power cable 260 is assembled to the portion where the unit connection cable 290 is connected to the master unit, that is, the right side connector connecting portion 180 in FIG.

  As described above, in this embodiment, the case covering the optical units 40 and 110 is roughly divided into three. That is, it is divided into an end case 130A, an intermediate case 35, and an end case 130B. The intermediate case 35 has a cylindrical shape, and the end cases 130A and 130B both have a bottomed cylindrical shape with a sealed peripheral wall, and a seal ring 170 is interposed in the fitting portion of each case. It is supposed to be inserted.

  When the cases are fitted together, the optical units 40 and 110 to be inserted are electrically connected to each other, and the fitting portion is sealed by the seal ring 170. With such a configuration, basically, the seal ring 170 that seals between the end case 130A and the intermediate case 35 and the seal ring 170 that seals between the intermediate case 35 and the end case 130B. With only two, it becomes possible to seal the entire case divided into three. Therefore, the number of seal members necessary to seal the entire case can be reduced as compared with the conventional seal structure.

  Further, as shown in FIG. 13, holding pieces 161 and 163 are positioned in front of and behind the seal ring 170, and the position is regulated so that the seal ring 170 is not displaced in the left-right direction shown in FIG. is doing. This increases the reliability of the sealing effect.

  In addition, in this embodiment, it is necessary to seal the connector connecting portion 180, but the power supply terminal 193 and the adjustment switch 195 are provided in the same portion, and both are sealed with one seal ring 270. Yes. With such a configuration, the number of seal members can be reduced as compared with the case where a dedicated seal member is provided for each of the power supply terminal 193 and the adjustment switch 195.

  The intermediate case 35 is provided with a plurality of types having different overall lengths, and is selectively used. With such a configuration, the cost can be reduced as compared to the case where all the parts are provided exclusively according to the number of connection stages of the optical unit 40. In addition, one optical unit 110 is fixedly accommodated in each of the end cases 130A and 130B, and the whole is made into a unit (end units 100A and 100B). If it is such a structure, it will become a form which is easy to handle and is excellent also in the management side.

  Further, the optical units 40 and 110 are provided with an arm 65 and a guide part 75, and the connecting operation of the optical units 40A and 40B is guided by the fitting of the arm 65 and the guide part 75. . With such a configuration, the optical units 40A and 40B can be easily connected.

  Further, since the optical units 40 and 110 are shielded by the shield case 55 or the like, it is possible to avoid malfunction of the apparatus due to noise entering from outside.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and further, within the scope not departing from the gist of the invention other than the following. Various modifications can be made.

  (1) In the above embodiment, the case surrounding the optical units 40 and 110 is divided into three. However, the case may be divided into two. That is, the intermediate case 35 is eliminated and the end cases 130A and 130B are fitted together.

  (2) In the above embodiment, in order to avoid erroneous assembly on the light projecting side and light receiving side, the groove widths of the guide grooves 67 and 68 and the protrusion widths of the fitting protrusions 77 and 78 are changed on the left and right. It is sufficient that at least the arm 65 does not fit into the guide portion 75 when the assembling occurs. For this purpose, the groove shape of the guide grooves 67 and 68 and the protrusion shape of the fitting protrusions 77 and 78 itself are included. The distance between the arms 65 may be changed between the light projecting side and the light receiving side.

The perspective view of the light curtain which concerns on one Embodiment of this invention. Perspective view of the receiver Disassembled perspective view of the receiver Exploded perspective view of the detector body Side view of optical unit Plan view of optical unit The optical unit viewed from the direction A in FIG. The optical unit viewed from the direction B in FIG. The figure which shows the connection structure of optical units CC line in FIG. 6, sectional view Cross section of end unit Diagram showing the connection structure between the end unit and the intermediate case HH sectional view taken on the line in FIG. FF sectional view in FIG. GG sectional view in FIG. The exploded perspective view which expanded the H section in Drawing 2 An enlarged plan view of the end of the end case Sectional drawing which shows the state before connecting a power cable Sectional view showing the state where the power cable is connected The figure which shows the state which connected the light emitters and the light receivers Figure showing a conventional example

Explanation of symbols

35 ... Intermediate case 40 ... Optical unit 100A ... End unit 100B ... End unit 110 ... Optical unit 130A ... End case 160 ... Connection shaft 170 ... Seal ring (seal member)

Claims (11)

An optical unit having an electrical connection part for arranging photoelectric elements in a row and making electrical connection to the end part; and
At least one optical unit having a shape that is long in one direction that can be accommodated therein, and one end portion in the longitudinal direction for making the electrical connection with the other optical unit accommodated therein A pair of end cases that open as mouths, and are configured to accommodate the optical units in both end cases by fitting the connection ports of the end cases together while accommodating the optical units therein. Multi-optical axis photoelectric sensor,
The end case is hermetically sealed in a sealed state except for the connection port,
In the fitting portion where the end cases are fitted, a seal member is provided to seal between the two,
A multi-optical axis photoelectric sensor characterized in that when the connection ports of the both end cases are fitted together, the connected both end cases are sealed as a whole. A cylindrical translucent intermediate case that houses the optical unit therein and that has both ends opened as connection ports that allow electrical connection with the other of the optical unit,
The case is configured so that both cases are coupled by fitting the connection port of the intermediate case and the connection port of the end case together, and the seal member is inserted into the fitting portion,
2. The multi-optical axis photoelectric sensor according to claim 1, wherein when the end cases are respectively connected to both end portions of the intermediate case, the three cases are sealed as a whole. 3. The multi-optical axis photoelectric sensor according to claim 2, wherein the intermediate case is provided with a plurality of types having different overall lengths according to the number of connection stages of the optical unit. The multi-light according to claim 3, wherein one optical unit is fixedly accommodated in the end case, and the entire end case including the optical unit is an end unit. Axis photoelectric sensor. In the end case, provided with a connector connecting portion for electrical connection with others, in which the mating connector provided in the electric cable can be connected,
5. The connector according to claim 1, wherein a connector sealing member is inserted in a fitting portion between the connector connecting portion and the mating connector so as to seal between the two. A multi-optical axis photoelectric sensor according to claim 1. A condition changing means for changing the setting of a condition including at least a detection condition for the detection operation by the photoelectric element is provided,
This condition changing means is provided in a portion of the connector connecting portion facing the mating connector, and is sealed by the connector sealing member when the mating connector is connected,
6. The multi-optical axis photoelectric sensor according to claim 5, wherein the multi-optical axis photoelectric sensor is exposed when the mating connector is not connected and the condition can be changed by an external operation. Among the optical units, an end provided with the electrical connection portion is provided with an integral arm extending along the connecting direction of the optical unit, while the other optical unit which is the other side is provided with the same arm. The guide portion extending in the longitudinal direction of the arm is provided at a position facing the arm, and the connecting operation of both optical units is guided by the fitting of the arm and the guide portion. The multi-optical axis photoelectric sensor according to claim 6. The light projecting side having a light projecting element as the photoelectric element and the light receiving side having a light receiving element as the photoelectric element are arranged to face each other so that the light projecting element and the light receiving element form a plurality of optical axes. In the multi-optical axis photoelectric sensor
The multi-optical axis photoelectric sensor according to claim 7, wherein at least one of the arrangement and shape of the arm and the guide portion is changed between the light projecting side and the light receiving side. The optical unit is housed in the intermediate case in a state of being fixed to a cylindrical unit case, and the unit case is provided with a support protrusion that contacts the case inner wall of the intermediate case. The multi-optical axis photoelectric sensor according to any one of claims 2 to 8, wherein the multi-optical axis photoelectric sensor is provided. The multi-optical axis photoelectric sensor according to claim 9, wherein the unit case is a shield case made of metal. The outer periphery of the intermediate case and the end case is covered with a metal protective case having a light insertion window of a size that allows light projecting / receiving operation by the photoelectric element. The multi-optical axis photoelectric sensor according to claim 10.

Images