JP2012225741A - Sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sensor including a sensor element which can be arranged in a cylinder hole of a separator easily and accurately while suppressing damage of the sensor element when inserted into the cylinder hole of the separator.SOLUTION: In a gas sensor, electrode terminal parts 31-35 provided on a plate-like sensor element 10 are arranged to a cylinder hole 110 of a cylindrical separator 100 and the electrode terminal parts 31-35 are electrically connected with connection terminals in the cylinder hole 110. The separator 100 includes a first rib part 121 protruding toward a second side face 16 of the sensor element 10, and a first rib part 122 protruding toward a second side face 17 of the sensor element 10. The first rib part 121 has a straight portion 151 and a taper portion 152. The first rib part 122 has a straight portion 161 and a taper portion 162.

Description

  In the present invention, an electrode terminal provided on a plate-shaped sensor element is disposed inside a cylindrical insulating contact member (separator), and the electrode terminal is electrically connected to a connection terminal inside the separator. The present invention relates to a sensor that forms a current path.

  Conventionally, there is known a sensor in which a plate-shaped sensor element having a detection portion formed on the tip side directed toward a measurement object is assembled in a housing (see, for example, Patent Document 1). Examples of such sensors include gas sensors such as λ sensors, full-range air-fuel ratio sensors, oxygen sensors, and NOx sensors, and temperature sensors that perform temperature detection.

  Specifically, in the sensor described above, the sensor element includes a detection unit on the front end side in the axial direction (longitudinal direction), and an electrode terminal unit electrically connected to an electrode disposed on the detection unit on the rear end side surface. I have. In addition, a rear end side (electrode terminal portion) of the sensor element and a connection terminal having a leaf spring capable of elastic deformation (compression deformation) are arranged in the cylindrical hole of the cylindrical separator. At this time, the electrode terminal portion and the connection terminal are electrically connected by bringing the leaf spring of the connection terminal into contact with the electrode terminal portion of the sensor element.

JP 2006-337096 A

  As shown in FIG. 6, the separator 600 included in the conventional sensor has a cylindrical hole 610 in which the five connection terminals 700 and the sensor element 500 are arranged. Five electrode terminal portions 501 to 505 are provided on the rear end side surface of the sensor element 500. The three electrode terminal portions 501, 502, and 503 are provided side by side in the width direction of the sensor element 500 on one surface (surface) 514 of both end surfaces (hereinafter referred to as first side surfaces) in the thickness direction of the sensor element 500. Yes. The two electrode terminal portions 504 and 505 are provided side by side in the width direction of the sensor element 500 on the other surface (back surface) 515 of the first side surface of the sensor element 500.

  Further, the cylindrical hole 610 includes five terminal accommodating portions 611 to 615 and an element accommodating portion 619. The element housing portion 619 is a region provided at the center portion of the cylindrical hole 610 where the rear end side of the sensor element 500 is disposed. The terminal accommodating portions 611 to 615 are regions in which five connection terminals 700 provided from the element accommodating portion 619 toward the radially outer side are respectively disposed. The five connection terminals 700 arranged in the terminal accommodating portions 611 to 615 are connected to the electrode terminal portions 501 to 505 of the sensor element 500 arranged in the element accommodating portion 619, respectively.

  Further, a pair of wall portions opposed to both end surfaces 516 and 517 in the width direction of the sensor element 500 disposed in the element accommodating portion 619 in the inner peripheral wall of the cylindrical hole 610 (hereinafter referred to as second side surfaces 516 and 517). Are the ribs 621, 622. The ribs 621 and 622 restrict the movement of the sensor element 500 arranged in the element housing portion 619 in the width direction. Each of the ribs 621 and 622 has opposing surfaces 651 and 652 that extend substantially parallel to the second side surfaces 516 and 516 of the sensor element 500 disposed in the element housing portion 619. The opposing surfaces 651 and 652 are formed such that the length in the thickness direction is larger than the thickness of the sensor element 500 in plan view. Further, the gap width between the rib 621 and the rib 622 (the width direction distance between the facing surface 651 and the facing surface 652) is slightly larger than the width direction length of the sensor element 500 in order to avoid contact with the sensor element 500. ing.

  By the way, as shown in FIG. 7, when the sensor element 500 is inserted into the inside of the cylindrical hole 610 (specifically, the element accommodating portion 619), the sensor element 500 is arranged around its axis. May rotate. This is because the ribs 621 and 622 have a slight gap with the sensor element 500, so that the sensor element is inserted so as to fill the slight gap, and as a result, the sensor element rotates. This is because the. At this time, the second side surfaces 516 and 517 of the sensor element 500 are inclined with respect to the ribs 621 and 622, and the ridges of the sensor element 500 may come into contact with the ribs 621 and 622, causing the sensor element 500 to be lost.

  In particular, in the example shown in FIGS. 6 and 7, the electrode terminal portions 501 and 503 are formed up to the ridge portion of the sensor element 500. Therefore, as in the example illustrated in FIG. 7, when the ridge portion where the electrode terminal portion 501 is formed contacts the rib 621 when the sensor element 500 is inserted, the electrode terminal portion 501 may be lost due to breakage of the ridge portion. was there.

  Therefore, conventionally, it is necessary to assemble the sensor element 500 and the separator 600 with high accuracy, and image measurement and position / angle adjustment for the sensor element 500 and the separator 600 are required to be highly accurate.

  The present invention has been made to solve the above-described problems, and easily and accurately arranges a sensor element in a cylindrical hole while suppressing the loss of the sensor element when the separator is inserted into the cylindrical hole. An object of the present invention is to provide a sensor capable of performing the above.

  The sensor according to one aspect of the present invention has a plate shape extending in the axial direction, and at least one of the first side surfaces facing the measurement object at one end side and in the thickness direction orthogonal to the axial direction on the other end side. A sensor element having an electrode terminal portion formed on one of the first side surfaces, a cylindrical separator made of an insulating material, disposed on the radially outer side on the other end side of the sensor element, and the sensor element A connection terminal that is disposed between the separator and is electrically connected to the electrode terminal portion to form a current path. Two first partition walls projecting toward both second side surfaces of the sensor element facing the width direction perpendicular to the direction and the thickness direction, and restricting movement of the sensor element in the width direction, Of the first bulkhead At least one of the opposing surfaces forming a planar shape along the second side surface while facing a part of the second side surface when viewed along the axial direction from the other end side in the axial direction. A straight portion having a taper portion that is connected to at least one of both ends of the facing surface and has an inclined surface that faces the remaining portion of the second side surface and inclines in a direction away from the second side surface; It has.

  According to the sensor of one aspect of the present invention, the separator is provided with two first partition walls that restrict the movement of the sensor element in the width direction, and the straight portion and the taper portion are provided on at least one of the two first partition walls. It was. Among these, the taper portion has an inclined surface that faces the remaining portion of the second side surface of the sensor element and is inclined in a direction away from the second side surface. Thereby, even if the sensor element rotates around the axial direction, the inclined surface and the ridge portion of the sensor element do not contact each other. As a result, it is possible to prevent the sensor element from being lost when the separator is inserted into the cylindrical hole.

  In addition, the first partition wall has a straight portion that faces part of the second side surface of the sensor element and restricts movement of the sensor element in the width direction. Thereby, it can restrict | limit reliably that the sensor element inserted in the cylinder hole of a separator moves to the width direction.

  The “opposing surface that opposes a part of the second side surface” or “the inclined surface that opposes the remaining part of the second side surface” means that the separator and the sensor element are arranged along the axial direction from the other end side in the axial direction. When viewed (state of FIG. 4 to be described later), it indicates that the opposing surface and the inclined surface overlap the second side surface at the position in the thickness direction.

  In addition, if a straight part and a taper part are provided in one of two first partition walls, the above-mentioned effect can be sufficiently obtained, but they may be provided in both of the two first partition walls. In this case, even if the sensor element rotates clockwise or counterclockwise, it can be reliably suppressed that the sensor element is lost when the separator is inserted into the cylindrical hole.

  In addition, if at least one tapered portion is provided on the first partition, the above effect can be obtained sufficiently, but two may be provided on the first partition. In this case, it is possible to prevent the ridges on both first side surfaces of the sensor element from contacting the inclined surface. As a form which provides two taper parts in a 1st partition, it can achieve by providing in a thickness direction on both sides of a straight part.

  In the sensor according to one aspect of the present invention, a plurality of the electrode terminal portions are formed on at least one of the first side surfaces, and the connection terminals correspond to the plurality of electrode terminal portions, and the sensor element And a plurality of the separators projecting toward the first side surface in the cylindrical hole, restricting movement of the sensor element in the thickness direction, and the plurality of electrode terminal portions And a plurality of the current paths formed by the plurality of metal terminal portions, and a second partition that insulates the current paths from each other, and a corner portion extending in the axial direction is formed at a connection position between the facing surface and the inclined surface. The shortest distance in the thickness direction between the protruding end of the second partition and the corner may be smaller than the thickness of the sensor element.

  When the sensor element rotates, the second side surface of the sensor element may deviate from the facing surface of the straight portion of the first partition wall, and the sensor element may enter a portion of the cylindrical hole of the separator that is enlarged at the tapered portion. . On the other hand, when the separator is provided with the second partition wall that restricts the movement of the sensor element in the thickness direction, the sensor element between the corner portion extending to the connection position between the facing surface and the inclined surface and the protruding end of the second partition wall The shortest distance in the thickness direction is made smaller than the thickness of the sensor element. Thereby, at the time of insertion of the separator into the cylindrical hole, the sensor element can be prevented from entering a portion of the cylindrical hole that is enlarged by the tapered portion. That is, the second side surface of the sensor element can be reliably opposed to the opposing surface of the straight portion provided in the first partition.

  Further, in the sensor according to one aspect of the present invention, at least one of the plurality of electrode terminal portions is provided so as to overlap a ridge portion extending along the axial direction in the first side surface. The taper portion may be provided at least on the first side surface side where the one electrode terminal portion of the first partition wall overlaps the ridge portion in the thickness direction. According to this, a taper part opposes the remainder of the 1st side surface provided so that one electrode terminal part might overlap with a ridge part. In this case, when the separator is inserted into the cylindrical hole, at least the ridge portion of the sensor element in which the electrode terminal portion is formed can be prevented from contacting the separator, and the electrode terminal portion can be prevented from being lost.

  Moreover, the sensor which concerns on 1 aspect of this invention WHEREIN: The said corner | angular part may be shifted and provided in the said 1st side surface side rather than the center of the said sensor element in the said thickness direction. According to this, a corner | angular part is shifted and provided in the 1st side surface in which the some electrode terminal part was formed among both 1st side surfaces. In this case, a part of the opposing second side surface of the straight portion is larger than the remaining portion of the opposing second side surface of the tapered portion. Therefore, the loss of the sensor element can be suppressed by the tapered portion while sufficiently exhibiting the function of restricting the movement of the sensor element in the width direction by the straight portion.

1 is a longitudinal sectional view of a gas sensor 1. FIG. 1 is a perspective view showing an external appearance of a sensor element 10. FIG. It is a perspective view which shows the external appearance of the separator 100. 2 is a plan view of a separator 100. FIG. 2 is a plan view of a separator 100. FIG. It is a top view of the separator 600 with which the conventional sensor is provided. It is a top view of the separator 600 with which the conventional sensor is provided.

  Embodiments of a sensor embodying the present invention will be described below with reference to the drawings. First, the structure of the gas sensor 1 as an example will be described with reference to FIG. In FIG. 1, the axis O direction (indicated by a one-dot chain line) of the gas sensor 1 is shown as a vertical direction, and the front end portion 11 side of the sensor element 10 held inside is the front end side of the gas sensor 1 and the rear end portion 12 side. The description will be made as the rear end side of the gas sensor 1.

  A gas sensor 1 illustrated in FIG. 1 is attached to an exhaust pipe (not shown) of an automobile. The gas sensor 1 is a so-called all-region air condition in which the tip portion 11 of the sensor element 10 held inside is exposed to exhaust gas flowing in the exhaust pipe and detects the air-fuel ratio of the exhaust gas from the oxygen concentration in the exhaust gas. This is a fuel ratio sensor.

  The sensor element 10 is a narrow and plate-shaped (strip-shaped) element extending in the direction of the axis O (in FIG. 1, the horizontal direction on the paper is shown as the thickness direction, and the front and back direction on the paper is shown as the width direction). The gas sensor 1 mainly holds the sensor element 10 by holding the sensor element 10 in the metal cup 20 and further supporting the metal cup 20 in a metal shell 50 for attachment to an exhaust pipe (not shown) of an automobile. It has a structure held in the metal fitting 50.

  In the central portion 13 of the sensor element 10, a metal cup 20 made of metal having a bottomed cylindrical shape with the sensor element 10 inserted therein is disposed. The metal cup 20 is a holding member for holding the sensor element 10 in the metal shell 50, and the tip end portion 11 of the sensor element 10 protrudes from the opening 25 at the bottom of the cylinder. The tip portion 11 is a detection unit that detects an oxygen gas component in the exhaust gas. In order to protect the detection portion from poisoning by exhaust gas, the detection portion protection layer 9 is covered so as to cover the outer surface thereof.

  The peripheral edge 23 at the edge of the cylindrical bottom of the metal cup 20 is formed in a tapered shape over the outer peripheral surface. In the metal cup 20, an alumina ceramic ring 21 and a talc ring 22 obtained by compressing and solidifying talc powder are accommodated in a state where the sensor element 10 is inserted through the ring. The talc ring 22 is crushed in the metal cup 20 so as to be filled in detail, whereby the sensor element 10 is positioned and held in the metal cup 20.

  The sensor element 10 integrated with the metal cup 20 is surrounded and held by a cylindrical metal shell 50. The metal shell 50 is made of low carbon steel such as SUS430, and has a male screw portion 51 for attachment to the exhaust pipe at the outer peripheral tip side. A distal end engaging portion 56 to which a protector 8 described later is engaged is formed on the distal end side of the male screw portion 51. At the center of the outer periphery of the metal shell 50, a tool engaging portion 52 with which a tool for attachment is engaged is formed. A gasket 55 is inserted between the front end surface of the tool engaging portion 52 and the rear end of the male screw portion 51 to prevent gas escape when attached to the exhaust pipe. On the rear end side of the tool engagement portion 52, a rear end engagement portion 57 with which an outer cylinder 65 to be described later is engaged, and on the rear end side, for caulking and holding the sensor element 10 in the metal shell 50. A caulking portion 53 is formed.

  A step portion 54 is formed in the vicinity of the male screw portion 51 on the inner periphery of the metal shell 50. The step 54 is engaged with the peripheral edge 23 of the tip of the metal cup 20 that holds the sensor element 10. Further, a talc ring 26 is loaded on the inner periphery of the metal shell 50 from the rear end side of the metal cup 20 with the sensor element 10 inserted therethrough. A cylindrical sleeve 27 is fitted into the metal shell 50 so as to press the talc ring 26 from the rear end side. A shoulder portion 28 having a step shape is formed on the outer periphery of the rear end side of the sleeve 27. An annular caulking packing 29 is disposed on the shoulder 28. In this state, the crimping portion 53 of the metal shell 50 is crimped so as to press the shoulder portion 28 of the sleeve 27 toward the distal end side via the crimping packing 29. The talc ring 26 pressed by the sleeve 27 is crushed in the metal shell 50 and filled in details. The metal cup 20 and the sensor element 10 are positioned and held in the metal shell 50 by the talc ring 26 and the talc ring 22 preloaded in the metal cup 20.

  From the tip end (tip engaging portion 56) of the metal shell 50, the tip end portion 11 of the sensor element 10 held inside protrudes. A protector for protecting the distal end portion 11 of the sensor element 10 from contamination (degradable deposits such as fuel ash and oil components) in the exhaust gas, breakage due to moisture, etc. 8 is fitted and fixed by spot welding or laser welding. The protector 8 is a double structure constituted by a bottomed cylindrical inner protector 90 and a cylindrical outer protector 80 that surrounds the periphery in the radial direction with a gap between the outer peripheral surface of the inner protector 90. Have

  The exhaust gas introduced into the gap between the outer protector 80 and the inner protector 90 from the outer introduction hole 85 generates a swirling flow in a state of surrounding the outer periphery of the inner protector 90, and is separated into a gas component and moisture. The gas component is introduced into the inner protector 90 from the inner introduction hole 95, contacts the sensor element 10, and is discharged to the outside from the discharge port 97. On the other hand, moisture enters the inner protector 90 through the drain hole 96 and is discharged to the outside through the discharge port 97. With such a configuration, the front end portion 11 of the sensor element 10 is protected from contamination due to deposits in exhaust gas, breakage due to thermal shock caused by moisture, and the like.

  On the other hand, the rear end portion 12 of the sensor element 10 held inside protrudes from the rear end (caulking portion 53) of the metal shell 50. As will be described later, at the rear end portion 12 of the sensor element 10, five electrode terminal portions 31 to 35 (see FIG. 2) made of platinum (Pt) for taking out electrodes are formed. Further, a cylindrical separator 100 made of an insulating ceramic that holds five connection terminals 61 (two of which are shown in FIG. 1) is placed on the rear end portion 12 of the sensor element 10. In other words, the separator 100 is disposed on the radially outer side on the rear end side of the sensor element 10.

  The separator 100 also accommodates and protects each connection portion between the five lead wires 64 (three of which are shown in FIG. 1) drawn to the outside of the gas sensor 1 and each connection terminal 61. The five connection terminals 61 are arranged between the sensor element 10 and the separator 100 so as to contact (electrically connect) to the electrode terminal portions 31 to 35, respectively, and also to the five lead wires 64. Each is electrically connected. Thus, a current path for current flowing between the external device to which the lead wire 64 is connected and the electrode terminal portions 31 to 35 is formed.

  The outer cylinder 65 is made of stainless steel (for example, SUS304) and has a cylindrical shape, and is attached to the rear end side of the metal shell 50. The outer cylinder 65 covers and protects the rear end portion 12 of the sensor element 10 exposed from the rear end of the metal shell 50 and the periphery of the separator 100. The outer cylinder 65 has an opening end 66 on its front end side engaged with the outer periphery of the rear end engaging portion 57 of the metal shell 50 and is crimped from the outer peripheral side, and makes a round around the outer periphery, and the rear end engaging portion 57. And is fixed to the metal shell 50 by laser welding.

  In the gap between the outer cylinder 65 and the separator 100, a metal-made cylindrical holding metal fitting 70 is disposed. The holding metal fitting 70 has a support portion 71 configured by bending its rear end inward. The holding metal fitting 70 supports the separator 100 by engaging a support portion 71 with a flange portion 101 provided in a hook shape on the outer periphery of the rear end side of the separator 100 inserted into the holding metal fitting 70. In this state, the outer peripheral surface of the outer cylinder 65 where the holding metal fitting 70 is disposed is crimped, and the holding metal fitting 70 that supports the separator 100 is fixed to the outer cylinder 65.

  Further, a grommet 75 that closes the rear end of the outer cylinder 65 is disposed on the rear end side of the separator 100. The grommet 75 is formed with five lead wire insertion holes 76 (one of which is shown in FIG. 1) for taking out the five lead wires 64 to the outside.

  The configuration of the sensor element 10 will be described with reference to FIG. In FIG. 2, the length in the thickness direction of the sensor element 10 is the thickness L1, and the length in the width direction of the sensor element 10 is the width L2. As shown in FIG. 2, the sensor element 10 includes an element portion 18 formed in a plate shape extending in the axial direction (left and right direction in FIG. 2) and a heater 19 formed in a plate shape extending in the axial direction. Are laminated into a plate shape having a rectangular axial cross section. When viewed along the axial direction of the sensor element 10, the sensor element 10 has a rectangular shape whose longitudinal direction is the width direction, and has four ridges that are substantially perpendicular. The sensor element 10 used in the full-range air-fuel ratio sensor is a known element, but the schematic configuration is as follows.

  The element unit 18 is laminated between an oxygen concentration cell element having porous electrodes formed on both sides of a solid electrolyte substrate, an oxygen pump element having porous electrodes formed on both sides of the solid electrolyte substrate, and the two elements. And a spacer for forming a hollow measurement gas chamber. The solid electrolyte substrate is formed from zirconia in which yttria is dissolved as a stabilizer. The porous electrode is formed mainly of Pt. The spacer forming the measurement gas chamber is mainly composed of alumina. Inside the hollow measurement gas chamber, one porous electrode of the oxygen concentration cell element and one porous electrode of the oxygen pump element are disposed so as to be exposed. The measurement gas chamber is formed so as to be positioned at the tip portion 11 of the sensor element 10, and the portion where the measurement gas chamber is formed corresponds to the detection unit. The heater 19 is formed by sandwiching a heating resistor pattern mainly composed of Pt between insulating substrates mainly composed of alumina.

  Of the outer surface on the rear end side of the sensor element 10, the surfaces having the front and back positional relationship are the first side surfaces 14 and 15, and the surfaces having the left and right positional relationship are the second side surfaces 16 and 17. Five electrode terminal portions 31 to 35 are formed on the first side surfaces 14 and 15. In other words, the first side surfaces 14 and 15 are both side surfaces facing the thickness direction orthogonal to the axial direction of the sensor element 10, and the second side surfaces 16 and 17 are both side surfaces facing the width direction of the sensor element 10. Three electrode terminal portions 31, 32, 33 are formed on the rear end side (right side in FIG. 2) of the first side surface 14, and two electrode terminal portions 34, 35 are formed on the rear end side of the first side surface 15. Has been. In the present embodiment, among the five electrode terminal portions 31 to 35, the two electrode terminal portions 31 and 33 are provided so as to overlap both ridge portions of the first side surface 14 extending along the axial direction of the sensor element 10. ing.

  The electrode terminal portions 31, 32, and 33 are formed in the element portion 18, one of which is one porous electrode of the oxygen concentration cell element and one of the oxygen pump elements that are exposed inside the measurement gas chamber. It is electrically connected in the form shared with the porous electrode. The remaining two electrode terminal portions of the electrode terminal portions 31, 32, and 33 are electrically connected to the other porous electrode of the oxygen concentration cell element and the other porous electrode of the oxygen pump element, respectively. The electrode terminal portions 34 and 35 are formed in the heater 19 and are connected to both ends of the heating resistor pattern via vias (not shown) that cross the heater 19 in the thickness direction.

  Next, the configuration of the separator 100 will be described with reference to FIGS. In addition, the upper side, the lower side, the lower right side, the upper left side, the upper right side, and the lower left side of FIG. 3 will be described as the upper side, the lower side, the front side, the rear side, the left side, and the right side of the separator 100, respectively. The upper side, the lower side, the left side, and the right side of FIGS. 4 to 6 will be described as the front side, the rear side, the left side, and the right side of the separator 100, respectively. In FIG. 4, the five connection terminals 61 arranged in the separator 100 are omitted for easy understanding.

  As shown in FIGS. 3 and 4, the separator 100 is made of alumina, is formed in a cylindrical shape having a cylindrical hole 110 penetrating in the axial direction, and protrudes radially outward from the outer surface. 101 is provided. The cylindrical hole 110 includes five terminal accommodating portions 111 to 115 and an element accommodating portion 119. The element accommodating portion 119 is a space provided in the center of the cylindrical hole 110 in the plan view and extending in the axial direction, and the rear end side of the sensor element 10 is disposed. The terminal accommodating portions 111 to 115 are spaces extending in the axial direction from the element accommodating portion 119 toward the outer side in the radial direction, and each of the five connecting terminals 61 is disposed (see FIG. 4).

  When the sensor element 10 is arranged at an appropriate position and inclination (position and inclination of the sensor element 10 shown in FIG. 4) in the element accommodating portion 119, the sensor element 10 is in an appropriate installation state. At this time, the thickness direction of the sensor element 10 is parallel to the longitudinal direction of the separator 100 (vertical direction in FIG. 4), and the width direction of the sensor element 10 is parallel to the lateral direction of the separator 100 (horizontal direction in FIG. 4). The axial direction of the sensor element 10 is parallel to the axial direction of the separator 100. In the state where the separator 100 is assembled to the gas sensor 1, the axial direction of the separator 100 coincides with the axial O direction of the gas sensor 1 (see FIG. 1).

  Second rib portions 131 and 132 projecting inward (downward in FIG. 4) are formed on the inner wall surface of the cylindrical hole 110 facing the first side surface 14 of the sensor element 10 disposed in the element accommodating portion 119. Has been. In other words, the second rib portions 131 and 132 are wall surfaces that protrude toward the first side surface 14 in the cylindrical hole 110, and the protruding widths thereof are substantially equal. The second rib portions 131 and 132 form boundaries of the three terminal accommodating portions 111, 112, and 113 for individually disposing the three connection terminals 61 in an electrically insulated state. Each terminal accommodating part 111,112,113 is formed in the position corresponding to the electrode terminal part 31,32,33 provided in the 1st side surface 14, respectively.

  A third rib portion 133 that protrudes inward (upward in FIG. 4) is formed on the inner wall surface of the cylindrical hole 110 that faces the first side surface 15 of the sensor element 10 disposed in the element accommodating portion 119. Yes. In other words, the third rib portion 133 is a wall surface protruding toward the first side surface 15 in the cylindrical hole 110 and faces the second rib portions 131 and 132 in the front-rear direction (vertical direction in FIG. 4). The third rib portion 133 forms a boundary between the two terminal accommodating portions 114 and 115 for individually arranging the two connection terminals 61 in an electrically insulated state. The terminal accommodating portions 114 and 115 are formed at positions corresponding to the electrode terminal portions 34 and 35 on the first plate surface 15, respectively.

  The five connection terminals 61 accommodated in the terminal accommodating portions 111 to 115 are connected to the electrode terminal portions 31 to 35 of the sensor element 10 disposed in the element accommodating portion 119, respectively. The 2nd rib parts 131 and 132 and the 3rd rib part 133 have a function which prevents that the connection terminals 61 arrange | positioned at the adjacent terminal accommodating parts 111-115 contact. As a result, the connection terminals 61 arranged adjacent to each other are prevented from being electrically connected to each other, and a current path failure is suppressed.

  The distance L3 between the protruding ends of the second rib portions 131 and 132 and the protruding end of the third rib portion 133 in the thickness direction of the sensor element 10 in the proper installation state (vertical direction in FIG. 4) is the sensor element 10. Is slightly larger than the thickness L1 (see FIG. 2). This is because the movement of the sensor element 10 in the thickness direction by the second rib parts 131 and 132 and the third rib part 133 can be restricted while avoiding contact with the sensor element 10 disposed in the element housing part 119. .

  A first rib portion 121 that protrudes inward (rightward in FIG. 4) is formed on the inner wall surface of the cylindrical hole 110 that faces the second side surface 16 of the sensor element 10 disposed in the element accommodating portion 119. Yes. In addition, a first rib portion 122 that protrudes inward (leftward in FIG. 4) is formed on the inner wall surface of the cylindrical hole 110 that faces the second side surface 17 of the sensor element 10 disposed in the element housing portion 119. Has been. The first rib portions 121 and 122 are wall surfaces protruding toward the second side surfaces 16 and 17 in the cylindrical hole 110, respectively, and are opposed so as to be symmetric in plan view. The first rib portion 121 forms a boundary between the two terminal housing portions 111 and 114, and the first rib portion 122 forms a boundary between the two terminal housing portions 113 and 115.

  The distance L4 between the protruding end of the first rib portion 121 and the protruding end of the first rib portion 122 in the width direction of the sensor element 10 in the proper installation state (left-right direction in FIG. 4) is the width L2 of the sensor element 10. It is slightly larger than (see FIG. 2). Therefore, the movement of the sensor element 10 in the width direction by the first rib portions 121 and 122 can be restricted while avoiding contact with the sensor element 10 disposed in the element housing portion 119.

  The first rib portion 121 is a straight portion that is a wall surface continuous at different inclinations when viewed from the upper end side (upper side in FIG. 3) along the axial direction of the separator 100 (that is, in a plan view shown in FIG. 4). 151 and a tapered portion 152. The straight portion 151 is opposed to a part of the second side surface 16 of the sensor element 10 disposed in the element accommodating portion 119 (in FIG. 4, the rear side portion of the second side surface 16) in plan view. It has an opposing surface 151 a that forms a flat surface along the side surface 16. The tapered portion 152 is connected to the straight portion 151. The tapered portion 152 is connected to the front end of the opposing surface 151a of the straight portion 151 in a plan view, and the remaining portion of the second side surface 16 of the sensor element 10 disposed in the element accommodating portion 119 (the second side surface in FIG. 4). 16, and an inclined surface 152 a that is inclined in a direction away from the second side surface 16 (upper left direction in FIG. 4). A corner portion 153 extending in the axial direction of the separator 100 is formed at a connection position between the facing surface 151 a of the straight portion 151 and the inclined surface 152 a of the tapered portion 152.

  Similarly, the first rib portion 122 is a wall surface continuous at different inclinations when viewed from the upper end side (upper side in FIG. 3) along the axial direction of the separator 100 (that is, in a plan view shown in FIG. 4). A straight portion 161 and a tapered portion 162 are included. The straight portion 161 is opposed to a part of the second side surface 17 of the sensor element 10 disposed in the element accommodating portion 119 (in FIG. 4, the rear side portion of the second side surface 17) in plan view. It has a facing surface 161 a that forms a planar shape along the side surface 17. The tapered portion 162 is connected to the straight portion 161. The tapered portion 162 is connected to the front end of the opposing surface 161a of the straight portion 161 in plan view, and the remaining portion of the second side surface 17 of the sensor element 10 disposed in the element accommodating portion 119 (the second side surface in FIG. 4). 17, and an inclined surface 162 a that is inclined in a direction away from the second side surface 17 (upper right direction in FIG. 4). A corner portion 163 extending in the axial direction of the separator 100 is formed at a connection position between the facing surface 161 a of the straight portion 161 and the inclined surface 162 a of the tapered portion 162.

  When the gas sensor 1 is manufactured, the sensor element 10 is inserted into the cylindrical hole 110 from above the separator 100, and the sensor element 10 is disposed in the element housing portion 119. At this time, the sensor element 10 may move in the thickness direction (vertical direction in FIG. 4) from the proper installation state, or may move in the width direction (left and right direction in FIG. 4) from the proper installation state. is there. Further, the sensor element 10 may rotate around its axis with respect to an appropriate installation state. That is, the sensor element 10 may rotate around the center in plan view (point P shown in FIG. 4).

  In the example shown in FIG. 5, when the sensor element 10 is inserted into the cylindrical hole 110, the sensor element 10 rotates counterclockwise in a plan view with respect to an appropriate installation state, and the first side surface 14 comes into contact with the second rib portion 132. The first side surface 15 is in contact with the third rib portion 133.

  Thus, when the sensor element 10 rotates around its axis with respect to an appropriate installation state, the sensor element 10 may come into contact with the first rib portions 121 and 122. In the example illustrated in FIG. 5, the second side surface 16 is in contact with the corner portion 153 of the first rib portion 121 due to the sensor element 10 rotating counterclockwise in plan view. However, the ridge portion of the sensor element 10 that protrudes most toward the left side of the separator 100 (that is, the ridge portion formed by the first side surface 14 and the second side surface 16) is in contact with the first rib portion 121 by the taper portion 152. Not.

  Although not shown, when the sensor element 10 rotates clockwise in plan view, the second side surface 17 may come into contact with the corner portion 163 of the first rib portion 122. However, the ridge portion of the sensor element 10 that protrudes most toward the right side of the separator 100 (that is, the ridge portion formed by the first side surface 14 and the second side surface 17) does not contact the first rib portion 122 by the tapered portion 162. .

  As described above, the tapered portions 152 and 162 have the inclined surfaces 152a and 162a that are opposed to the remaining portions of the second side surfaces 16 and 17 of the sensor element 10 and are inclined in a direction away from the second side surfaces 16 and 17, respectively. Therefore, even when the sensor element 10 rotates around the axial direction when inserted into the cylindrical hole 110, it is possible to suppress the sensor element 10 (particularly, the ridge portion) from coming into contact with the separator 100 and being lost. it can. As a result, it can suppress that the chip | tip missing from the sensor element 10 is bitten between each connection terminal 61 and the electrode terminal parts 31-35. As a result, the contact failure of the current path formed in the gas sensor 1 can be suppressed, and the quality of the gas sensor 1 can be improved.

  By the way, as a technique for preventing the ridge portion of the sensor element 10 from being damaged when inserted into the cylindrical hole 110, it is conceivable to chamfer the ridge portion of the sensor element 10. However, when the sensor element 10 has a multi-terminal structure, the number of electrode terminal portions provided on the first side surfaces 14 and 15 increases. Therefore, when the chamfering of the ridge portion of the sensor element 10 is performed, the length in the width direction of the first side surfaces 14 and 15 is reduced, so that the installable area of the electrode terminal portion is also reduced (that is, the number of installable electrode terminal portions May decrease). On the other hand, in this embodiment, since it is not necessary to chamfer the ridge portion of the sensor element 10, the corner portion of the sensor element 10 is damaged while reducing the restriction on the number of electrode terminals that can be installed in the sensor element 10. Can be suppressed.

  Further, the taper portion 152 is provided at a position facing a portion adjacent to the first side surface 14 where the two electrode terminal portions 31 and 33 overlap both ridge portions (in FIG. 4, the front side portion of the second side surface 16). Yes. Similarly, the taper portion 162 is provided at a position facing the portion adjacent to the first side surface 14 where the two electrode terminal portions 31 and 33 overlap both ridge portions (the front portion of the second side surface 17 in FIG. 4). ing. In other words, the taper portions 152 and 162 are formed so that the two electrode terminal portions 31 and 33 are both ridges in the first side surface 1415 in the thickness direction of the sensor element 10 in the proper installation state (vertical direction in FIG. 4). It is provided on the side of the first side surface 14 that overlaps the part. Thereby, it can suppress that the ridge part of the sensor element 10 in which the electrode terminal parts 31 and 33 were formed contacts the separator 100 at the time of insertion to the cylinder hole 110, and that the electrode terminal parts 31 and 33 are missing | damped by extension. Can be suppressed.

  In addition, the corners 153 and 163 are centered in plan view of the sensor element 10 (in FIG. 4) of the first side surfaces 14 and 15 in the thickness direction of the sensor element 10 in the proper installation state (vertical direction in FIG. 4). It is shifted from the point P) to the first side surface 14 side where the two electrode terminal portions 31 and 33 are formed. Thereby, a part of the second side surface 16 facing the straight portion 151 becomes larger than the remaining portion of the second side surface 16 facing the tapered portion 152. Similarly, a part of the opposing second side surface 17 of the straight portion 161 is larger than the remaining portion of the opposing second side surface 17 of the tapered portion 162. Therefore, the loss of the sensor element 10 can be suppressed by the tapered portions 152 and 162 while sufficiently exhibiting the function of restricting the movement of the sensor element 10 in the width direction by the straight portions 151 and 161.

  Furthermore, in the present embodiment, the shortest distance L5 between the protruding end of the second rib portion 131 and the corner portion 153 in the thickness direction (vertical direction in FIG. 4) of the sensor element 10 in an appropriate installation state is the sensor element 10. The thickness L1 is smaller than the thickness L1 (see FIG. 2). Similarly, in the thickness direction (vertical direction in FIG. 4) of the sensor element 10 in an appropriate installation state, the shortest distance L6 between the protruding end of the second rib portion 132 and the corner portion 163 is the thickness L1 ( (See FIG. 2). Accordingly, as shown in FIG. 5, even when the separator 100 rotates, the second side surfaces 16 and 17 of the sensor element 10 are opposed to the opposing surfaces 151 a and 161 a of the straight portions 151 and 161 of the first rib portions 121 and 122. Can be prevented from entering the region enlarged by the tapered portions 152 and 162 in the cylindrical hole 110 of the separator 100. That is, the second side surfaces 16 and 17 of the sensor element 10 can be reliably opposed to the opposed surfaces 151a and 161a of the straight portions 151 and 161 provided on the first rib portions 121 and 122, respectively.

  By the way, in the said embodiment, the gas sensor 1 corresponds to the "sensor" of this invention. The first rib portions 121 and 122 correspond to the “first partition wall” of the present invention. The second rib portions 131 and 132 correspond to the “second partition wall” of the present invention.

  The present invention is not limited to the embodiment described in detail above, and various modifications may be made without departing from the scope of the present invention. In the above embodiment, the first rib portion 121 is provided with the tapered portion 152, and the first rib portion 122 is provided with the tapered portion 162. It may replace with this and may provide a taper part in any one of the 1st rib parts 121 and 122. FIG.

  Moreover, in the said embodiment, in the 1st rib parts 121 and 122, the taper parts 152 and 162 are provided in the 1st side surface 14 side in the thickness direction of the sensor element 10, respectively. Instead of this, the tapered portion may be provided on the first side surface 15 side in the thickness direction of the sensor element 10. In the first rib portions 121 and 122, two tapered portions may be provided on both the first side surfaces 14 and 15 side in the thickness direction of the sensor element 10 so as to sandwich the straight portions 151 and 161.

  Moreover, in the said embodiment, although the three electrode terminal parts 31-33 are provided in the 1st side surface 14 of the sensor element 10, and the two electrode terminal parts 34 and 35 are provided in the 1st side surface 15, The number and shape of the electrode terminal portions provided on the side surfaces 14 and 15 can be changed. Further, the corner portions 153 and 163 provided in the first rib portions 121 and 122 are not limited to pin angles, but may be R angles.

  In the above embodiment, the tapered portions 152 and 162 are formed along the axis O direction of the separator 100. Instead of this, the tapered portion may be formed at least up to the position where the sensor element 10 is inserted in the cylindrical hole 110.

  Moreover, in the said embodiment, the gas sensor 1 which is a full range air-fuel ratio sensor was illustrated as one aspect | mode of the sensor which concerns on this invention. In the present invention, an electrode terminal provided on a plate-shaped sensor element is disposed inside a cylindrical insulating contact member (separator), and the electrode terminal is electrically connected to a connection terminal inside the separator. Any sensor that forms a current path can be applied. For example, the present invention may be applied to a gas sensor such as a λ sensor, an oxygen sensor, or a NOx sensor, or a temperature sensor that detects temperature.

DESCRIPTION OF SYMBOLS 1 Gas sensor 10 Sensor element 14, 15 1st side surface 16, 17 2nd side surface 31,32,33,34,35 Electrode terminal part 61 Connection terminal 100 Separator 110 Cylindrical hole 111,112,113,114,115 Terminal accommodating part 119 Element receiving portion 121, 122 First rib portion 131, 132 Second rib portion 133 Third rib portion 151, 161 Straight portion 152, 162 Tapered portion 153, 163 Corner portion

Claims (4)

An electrode terminal is formed on at least one of the first side surfaces of the first side surfaces which are formed in a plate shape extending in the axial direction, and whose one end side is directed to the measurement object and which faces the thickness direction perpendicular to the axial direction on the other end side. A sensor element in which a portion is formed;
A cylindrical separator made of an insulating material, disposed on the radially outer side on the other end side of the sensor element,
A connection terminal disposed between the sensor element and the separator and electrically connected to the electrode terminal portion to form a current path;
A sensor comprising:
The separator protrudes toward both second side surfaces of the sensor element facing in the width direction perpendicular to the axial direction and the thickness direction in its cylindrical hole, and the movement of the sensor element in the width direction is performed. Two first bulkheads to regulate,
When at least one of the two first partition walls is viewed along the axial direction from the other end side in the axial direction,
A straight portion having a facing surface that forms a planar shape along the second side surface while facing a part of the second side surface;
A tapered portion that is connected to at least one of both ends of the facing surface, has a sloped surface that faces the remaining portion of the second side surface and slopes away from the second side surface;
A sensor comprising: A plurality of the electrode terminal portions are formed on at least one of the first side surfaces,
A plurality of the connection terminals are arranged between the sensor element and the separator corresponding to the plurality of electrode terminal portions,
The separator protrudes toward the first side surface in the cylindrical hole, restricts movement of the sensor element in the thickness direction, and is formed by the plurality of electrode terminal portions and the plurality of metal terminal portions. A plurality of current partitions that insulate the current paths from each other,
A corner portion extending in the axial direction is formed at a connection position between the facing surface and the inclined surface,
2. The sensor according to claim 1, wherein the shortest distance in the thickness direction between the protruding end of the second partition and the corner is smaller than the thickness of the sensor element. Among the plurality of electrode terminal portions, at least one of the electrode terminal portions is provided so as to overlap a ridge portion extending along the axial direction of the first side surface,
The taper portion is provided at least on the first side surface side in which the one electrode terminal portion of the first partition wall overlaps the ridge portion in the thickness direction. Sensor.   4. The sensor according to claim 2, wherein the corner portion is provided in the thickness direction so as to be shifted toward the first side surface side from the center of the sensor element. 5.

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