Multi-optical axis photoelectric sensor comprising a light transmissive plate disposed to straddle the body housing and a pair of caps
10309827 ยท 2019-06-04
Assignee
Inventors
Cpc classification
International classification
Abstract
A multi-optical axis photoelectric sensor includes: a pair of body-side packings which seal between a body housing and both side edges of a light transmissive plate; first packings which seal between caps and the side edges of the light transmissive plate, and between the caps and end portions of the light transmissive plate, and which are connected to the pair of body-side packings; and second packings which are integrally molded with the first packings, respectively, and which seal between the caps and the body housing.
Claims
1. A multi-optical axis photoelectric sensor comprising: a body housing having openings in a front surface and both end portions; a pair of caps that respectively close the openings of the both end portions of the body housing; a light transmissive plate that closes the opening of the front surface of the body housing, wherein through which light of photoelectric elements is transmissible through the light transmissive plate, and the light transmissive plate is disposed to straddle the body housing and the pair of caps; a pair of first sealing portions that seal between the body housing and both side edges of the light transmissive plate; second sealing portions that seal between the caps and the side edges of the light transmissive plate and between the caps and end portions of the light transmissive plate, wherein the second sealing portions are connected to the pair of first sealing portions; and third sealing portions which are integrally molded with the second sealing portions respectively, and which seal between the caps and the body housing.
2. The multi-optical axis photoelectric sensor according to claim 1, wherein each of the second sealing portions includes: a pair of side portions that correspond between the both side edges of the light transmissive plate and the cap; an end-portion continuous portion that connects the side portions to each other in one end portions of the side portions, and that corresponds between a side of the end portion of the light transmissive plate and the cap; and a beam portion that connects the side portions to each other at a position that is separated from the end-portion continuous portion.
3. The multi-optical axis photoelectric sensor according to claim 1, wherein each of the second sealing portions includes: a pair of side portions that correspond between the both side edges of the light transmissive plate and the cap; a pair of connecting portions connected to the pair of first sealing portions; and crank portions which are provided between the side portions and the connecting portions, and which cause the connecting portions to be outwardly separated with respect to the pair of side portions.
4. The multi-optical axis photoelectric sensor according to claim 1, wherein the first sealing portions, the second sealing portions, and the third sealing portions form a polygonal shape having a plurality of planes.
5. The multi-optical axis photoelectric sensor according to claim 4, wherein each of the first sealing portions includes: a first butting surface that has a planer shape, and that butts against the light transmissive plate in a condition that the first sealing portion is clamped between the light transmissive plate and the body housing.
6. The multi-optical axis photoelectric sensor according to claim 1, wherein connecting surfaces between the first sealing portions and the second sealing portions are tapered surfaces.
Description
BRIEF DESCRIPTION OF DRAWINGS
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DESCRIPTION OF EMBODIMENTS
(13) Hereinafter, an embodiment of a multi-optical axis photoelectric sensor will be described with reference to the drawings.
(14) As shown in
(15) As shown in
(16) As shown in
(17) As shown in
(18) <Body Housing 31>
(19) As shown in
(20) As shown in
(21) As shown in
(22) <Caps 41>
(23) As shown in
(24) As shown in
(25) As shown in
(26) As shown in
(27) In each of the caps 41, as shown in
(28) As shown in
(29) <Packings 61, 71>
(30) In the light receiver 13 of the embodiment, as shown in
(31) <Body-Side Packings 61>
(32) As shown in
(33) Each of the body-side packings 61 has: a placement surface 62 which is to be placed on the corresponding second extending portion 35; a butting surface 63 which is approximately parallel to the placement surface 62, and which is to butt against the light transmissive plate 81; and two tapered surfaces (inclined surfaces) 64, 65 which are flared from the side of the butting surface 63 in a range between the placement surface 62 and the butting surface 63, and is formed so as to have a substantially trapezoidal shape.
(34) The placement surface 62 functioning as the second butting surface is formed so as to have a shape wider than the butting surface 63 functioning as the first butting surface.
(35) The one tapered surface 64 is a connection surface (bonding surface) which is buttingly connected to the cap-side packing 71 that will be described later.
(36) The other tapered surface 65 is configured by two tapered surfaces 65a, 65b which have different inclination angles with respect to the butting surface 63. The tapered surface 65a which is closer to the butting surface 63 has an inclination angle that is near the right angle with respect to the butting surface 63, and the tapered surface 65b which is closer to the placement surface 62 has an inclination angle that is near an obtuse angle with respect to the butting surface 63. Namely, the difference of the inclination angles of the tapered surface 65a and the tapered surface 65b enables the worker who performs an assembling work, to recognize that the shape is different from the shape of the tapered surface 64 which is to butt against the cap-side packing 71.
(37) Furthermore, an inner corner portion 65c between the tapered surface 65b and the placement surface 62 is formed so as to have a curved surface. The inner corner portion 65c is configured so as to butt in the lateral direction against the projection 35a of the second extending portion 35. Here, the inner corner portion 65c of the body-side packing 61 has a curved surface as described above, and therefore easily butts against the projection 35a.
(38) <Cap-Side Packings 71>
(39) As shown in
(40) The first packings 72 are packings which seal mainly the gaps between the caps 41 and the light transmissive plate 81.
(41) The first packings 72 seal between the caps 41 and the both side edges of the light transmissive plate 81, and between the caps 41 and the end portions of the light transmissive plate 81, and are connected to the pair of body-side packings 61.
(42) Each of the first packings 72 has: a pair of side portions 73 which correspond between the both side edges of the light transmissive plate 81 and the cap 41; an end-portion continuous portion 74 which causes the side portions 73 to be continuous to each other in one end portions of the side portions 73, and which corresponds between the end portion side of the light transmissive plate 81 and the cap 41; and two beam portions 75 which connect the side portions 73 to each other at positions that are separated from the end-portion continuous portion 74.
(43) The first packing 72 has: crank portions 76 which outwardly spread in the lateral direction with respect to the side portions 73, in the other end portions of the side portions 73; and a pair of connecting portions 77 which extend from the crank portions 76, and which are to be connected to the body-side packings 61. The first packing 72 is formed so as to have a polygonal shape (quadrangular shape) having a plurality of planes. Each of the connecting portions 77 is formed so that its section has a substantially parallelogram shape, and a tapered surface (inclined surface) 77a which is on the laterally inner side is to butt against (be press-bonded to) the tapered surface 64 of the above-described body-side packing 61.
(44) Each of the crank portions 76 has a crank shape in which the connecting portion 77 is outwardly widened in the lateral direction with respect to the side portion 73 by a degree corresponding to the width (the length in the lateral direction) of the body-side packing 61. According to the configuration, even in the case where the side portion 73 and the body-side packing 61 are aligned in a same straight line, for example, the crank portion 76 enables the connecting portion 77 to be placed at a position where it does not extremely interfere with the body-side packing 61. Even in a state where the body-side packing 61 is placed on the second extending portion 35 of the body housing 31, namely, it is possible to suppress a situation where, when the first packing 72 (the connecting portion 77) and the body-side packing 61 are to be placed (set) so as to butt against each other, the body-side packing 61 and the connecting portion 77 extremely interfere with each other to impede the setting work.
(45) The second packings 78 are packings which seal the gaps between the caps 41 and the body housing 31, and formed integrally with the first packings 72. The second packings 78 are formed so as to have a polygonal shape having a plurality of planes.
(46) <Light Transmissive Plate 81>
(47) As shown in
(48) As shown in
(49) <Pressing Members 91>
(50) The middle light transmissive portion 82 of the light transmissive plate 81 is clamped between two pressing members 91 and the packings 61, 71 by, in a state where the portion is placed on the packings 61, inserting the pressing members 91 between the middle light transmissive portion 82 and the first extending portions 34 of the body housing 31.
(51) At this time, the middle light transmissive portion 82 is rearwardly pressed in accordance with the insertion of the pressing members 91 as shown in
(52) <Cap Covers 101>
(53) As shown in
(54) <Protective Cover 111>
(55) In the light receiver 13 of the embodiment, as shown in
(56) The protective cover 111 is formed so as to have an elongated shape, and has a planar body portion 112, and elongated portions 113 which extend in a crank-like manner from the both side edges of the body portion 112. The elongated portions 113 are configured so that their tip end portions 113a extend to the both lateral sides, and the tip end portions 113a are engaged with the cap covers 101 and the pressing members 91 in the anteroposterior direction. The protective cover 111 employs the so-called snap fit fixation in which the cover is fitted and fixed to the cap covers 101 and the pressing members 91 by using own elastic deformation and elastic deformations of the cap covers 101 and the pressing members 91. According to the configuration, other fastening members and the like are not necessary, and the protective cover 111 can be easily fixed.
(57) Next, the function of the thus configured multi-optical axis photoelectric sensor will be described. The functions of the light projector 12 and light receiver 13 which are examples of the multi-optical axis photoelectric sensor are basically common to each other, and, in the following, the function of the light receiver 13 will be therefore exemplarily described.
(58) In the light receiver 13 of the embodiment, the gaps between the body housing 31 and the caps 41 are sealed by the second packings 78 of the cap-side packings 71. The cap-side packings 71 further seal the gaps between the caps 41 and the light transmissive plate 81. The gap between the body housing 31 and the light transmissive plate 81 is sealed by the pair (two) of body-side packings 61, and the connecting portions 77 and crank portions 76 of the cap-side packings 71.
(59) Here, the pair of body-side packings 61 are connected (press-bonded) in the both end portions to the connecting portions 77 of the cap-side packings 71. In the embodiment, namely, the number of the connecting portions of the packings 61, 71 is four.
(60) Next, effects of the embodiment will be described.
(61) (1) The first packings 72 functioning as the second sealing portions, and the second packings 78 functioning as the third sealing portions are integrally molded with each other, and therefore the first packings 72 and the second packings 78 are not required to be connected to each other by adhesion or press-bonding. That is, the connecting portions in the packings are formed only between the pair of body-side packings 61 and the first packings 72. In the case where the first packings 72 (the cap-side packings 71) are connected to the both end portions of the pair of body-side packings 61, respectively, namely, the connection is made at four places, and therefore the number of connecting portions can be reduced.
(62) (2) The light receiving elements 15 (the photoelectric elements) are housed also in the caps 41. Therefore, the above-described reduction of the connecting portions of the packings 61, 71 in the configuration where the first packings 72 seal between the caps 41 and the light transmissive plate 81 has large significance.
(63) (3) The disposition of the beam portions 75 which connect the side portions 73 of the first packing 72 can prevent the side portions 73 from inwardly falling down.
(64) (4) Each of the first packings 72 has the crank portions 76 which cause the connecting portions 77 to be outwardly separated with respect to the pair of side portions 73, between the side portions 73 and the connecting portions 77, and therefore the connecting portions 77 can be outwardly separated by the crank portions 76, so that the body-side packings 61 can be placed inner than the connecting portions 77. In the configuration, a work of setting the body-side packings 61 and the connecting portions 77 in the body housing 31 is easily performed. Moreover, for example, the side portions 73 of the first packing 72, and the body-side packing 61 can be placed substantially in a same straight line, and therefore it is possible to prevent the body-side packing 61 which is placed in the inner side, from being placed on the optical axes L of the light receiving elements 15 (the photoelectric elements).
(65) (5) The body-side packings 61 and the cap-side packings 71 are formed so as to have a polygonal shape having a plurality of planes. When butting of the packings 61, 71 against the components is to be performed, therefore, the butting through the planes performed. Consequently, the contact area can be widened as compared with a point contact. As a result, the sealing property can be enhanced.
(66) (6) Each of the body-side packings 61 is formed so that the placement surface 62 has a shape which is wider than the butting surface 63. When, in an assembling process, a force is applied to (compresses) the body-side packing 61 from the front surface side (the side of the light transmissive plate 81), therefore, the body-side packing can be stably held to the body housing 31 because the butting surface 62 has the wider shape. Also in the case where, in the compression of the body-side packing 61, a force in a twisting direction acts on the side of the butting surface 63 of the body-side packing 61, the butting surface 62 is stabilized, and therefore it is possible to prevent the body-side packing 61 from being twisted.
(67) (7) The connecting surfaces between the body-side packing 61 and the first packing 72 (cap-side packing 71) are the tapered surfaces 64, 77a, and therefore the connection can be made while forming the connecting surfaces between the body-side packing 61 and the first packing 72 as tapered surfaces (inclined surfaces). Consequently, a gap is hardly formed between the body-side packing 61 and the first packing 72, and the waterproofing property can be enhanced. Because of the tapered surfaces 64, 77a, furthermore, the contact area can be ensured while suppressing the lengths (thicknesses) of the packings 61 and the first packings 72 in the anteroposterior direction.
(68) The above-described embodiment can be changed in the following manners.
(69) Although the embodiment has the configuration where, in the first packing 72 of each of the cap-side packings 71, the side portions 73 are connected to each other by the two beam portions 75, a configuration where the side portions are not connected by the beam portions 75 may be employed. Moreover, the number of the beam portions 75 may be arbitrarily changed.
(70) Although the embodiment has the configuration where the first packing 72 of each of the cap-side packings 71 has the crank portions 76 which cause the connecting portions 77 to be outwardly separated with respect to the pair of side portions 73, a configuration where the crank portions 76 are omitted may be employed. In this case, the side portion 73 and the connecting portion 77 are aligned in a same straight line. At this time, the body-side packings 61 may be disposed so as to be located between the pair of connecting portions 77. Moreover, the body-side packings 61 may be disposed so as to be located laterally outside the pair of connecting portions 77. The connecting portions 77 and the body-side packings 61 may be disposed so as to butt against each other only in the anteroposterior direction.
(71) Although, in the embodiment, the body-side packings 61 and the cap-side packings 71 (the first packings 72 and the second packings 78) are formed to have a substantially quadrangular shape having a plurality of planes, another polygonal shape may be employed. Moreover, a columnar shape may be employed.
(72) Although, in the embodiment, the placement surface 62 functioning as the second butting surface is formed so as to have a shape which is wider than the butting surface 63 functioning as the first butting surface, a configuration where the placement surface 62 and the butting surface 63 have the same width, or that where the butting surface 63 has a shape which is wider than the placement surface 62 may be employed.
(73) Although not particularly described in the embodiment, the following configuration may be employed in the second packings 78 of the cap-side packings 71.
(74) As shown in
(75) Although, in the embodiment, the number of the photoelectric elements (the light projecting elements 14 and the light receiving elements 15) disposed in each of the multi-optical axis photoelectric sensors (the light projector 12 and the light receiver 13) constituting the light curtain 11 is fifteen, the number is not limited to this.
(76) Although, in the embodiment, the configuration where the photoelectric elements (the light projecting elements 14 or the light receiving elements 15) are disposed also in the caps is employed, a configuration where the photoelectric elements in the caps 41 are omitted may be employed.
(77) In the embodiment, the multi-optical axis photoelectric sensor may be used in an application other than a light curtain.
(78) The embodiment and the modifications may be adequately combined with each other.
(79) Next, technical concepts which can be known from the embodiment and the other examples will be additionally described in the followings.
(80) <Supplement 1> The multi-optical axis photoelectric sensor according to any one of claims 1 to 6, wherein
(81) the caps, the second sealing portions, and the third sealing portions are integrally molded by two-color molding.
(82) When the caps, the second sealing portions, and the third sealing portions are previously molded by two-color molding, therefore, an assembling process is not additionally required, and hence the man-hours for assembly can be reduced.
(83) <Supplement 2> The multi-optical axis photoelectric sensor according to any one of claims 1 to 6 or Supplement 1, wherein
(84) the third sealing portions are configured so as to, between the caps and the body housing, cover peripheral edges of the openings of the end portions of the body housing, and each of the third sealing portions has: a first edge portion which, in a state where the third sealing portion is interposed between the cap and the body housing, is located on the side of the rear surface of the body housing; a pair of second edge portions which are elongated from the both end portions of the first edge portion toward the front surface of the body housing; and a pair of third edge portions which are elongated from the second edge portions in an approaching direction, and
(85) a section which is taken in a direction perpendicular to an elongation direction of the first edge portion, and a section which is taken in a direction perpendicular to an elongation direction of the third edge portions are larger in size than a section which is taken in a direction perpendicular to the elongation direction of the second edge portions.
(86) According to the configuration, it is possible to prevent the second edge portions from inwardly falling down.
(87) <Supplement 3> The multi-optical axis photoelectric sensor according to any one of claims 1 to 6, Supplement 1, or Supplement 2, wherein
(88) the sensor further includes a positioning portion which positions the body housing and the caps.
(89) According to the configuration, it is possible to perform positioning of the body housing and the caps.
(90) Although the invention has been described in detail and with reference to the specific embodiment, it is obvious to a person skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.
(91) The application is based on Japanese Patent Application (No. 2015-073807) filed Mar. 31, 2015, and its disclosure is incorporated herein by reference.
REFERENCE NUMERALS AND SIGNS
(92) 11 . . . light curtain, 12 . . . light projector (multi-optical axis photoelectric sensor), 13 . . . light receiver (multi-optical axis photoelectric sensor), 14 . . . light projecting element (photoelectric element), 15 . . . light receiving element (photoelectric element), 31 . . . body housing, 31a, 31b, 41a . . . opening, 41 . . . cap, 61 . . . body-side packing (first sealing portion), 64 . . . tapered surface, 71 . . . cap-side packing (second sealing portion and third sealing portion), 72 . . . first packing (second sealing portion), 73 . . . side portion, 74 . . . end-portion continuous portion, 75 . . . beam portion, 76 . . . crank portion, 77 . . . connecting portion, 77a . . . tapered surface, 78 . . . second packing (third sealing portion), 81 . . . light transmissive plate.