Non-contact sensor

Abstract

To improve reliability of a non-contact sensor.SOLUTION: A non-contact sensor 1 detects an object 9. The non-contact sensor 1 includes a housing C1, a detection member 5, and a magnet 6. The housing C1 has a detection surface 310 opposing to the object 9. The detection member 5 is disposed inside the housing C1 and above the detection surface 310. The magnet 6 is disposed inside the housing C1 and on an upper side of the detection member 5. The detection member 5 detects magnetism to be generated by the magnet 6. The magnet 6 has a vertically penetrating through-hole. The detection member 5 overlaps with the through-hole when viewed from below.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates generally to non-contact sensors, and more particularly to non-contact sensors that magnetically detect objects. [Background technology]

[0002] The rotation detection sensor (non-contact sensor) described in Patent Document 1 includes a sensor and a holder that secures the sensor. The sensor has a magnet that generates magnetic flux and a detection element that includes a Hall IC or the like. The sensor detects changes in the magnetic flux density generated around the magnet using the detection element under conditions where the magnetic flux density changes due to the rotation of a rotating member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-310646 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure aims to improve the reliability of non-contact sensors. [Means for solving the problem]

[0005] A non-contact sensor according to one aspect of the present disclosure detects an object. The non-contact sensor includes a housing, a detection member, and a magnet. The housing has a detection surface facing the object. The detection member is disposed inside the housing and above the detection surface. The magnet is disposed inside the housing and above the detection member. The detection member detects magnetic fields generated by the magnet. The magnet has a through-hole that penetrates in the vertical direction. When viewed from below, the detection member overlaps the through-hole.

[0006] A non-contact sensor according to another aspect of the present disclosure detects an object. The non-contact sensor includes a housing, a detection member, and a plurality of magnets. The housing has a detection surface facing the object. The detection member is disposed inside the housing and above the detection surface. The plurality of magnets are disposed inside the housing and above the detection member. The detection member has an element unit that outputs a signal in response to the magnetism generated by the plurality of magnets. When viewed from below, the detection member is disposed inside the outer surfaces of the plurality of magnets. When viewed from below, the plurality of magnets do not overlap with the element unit. [Effects of the Invention]

[0007] The present disclosure has the advantage of improving the reliability of non-contact sensors. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a front view of a non-contact sensor according to a first embodiment. [Figure 2] FIG. 2 is a front view of the non-contact sensor. [Figure 3] FIG. 3 is a front view of the non-contact sensor. [Figure 4] FIG. 4 is a front cross-sectional view of the non-contact sensor. [Figure 5] FIG. 5 is a side cross-sectional view of the non-contact sensor. [Figure 6] FIG. 6 is a perspective view of a magnet of the non-contact sensor. [Figure 7] FIG. 7 is a bottom view of the magnet and the detection member of the non-contact sensor. [Figure 8] FIG. 8 is an exploded perspective view of the non-contact sensor. [Figure 9] FIG. 9 is an exploded perspective view of a main part of the non-contact sensor. [Figure 10] FIG. 10 is a perspective view showing the non-contact sensor with the cover removed. [Figure 11] FIG. 11 is an exploded perspective view of a main part of the non-contact sensor. [Figure 12] FIG. 12 is a perspective view of a magnet of the non-contact sensor according to the second embodiment. [Figure 13] FIG. 13 is a perspective view of a plurality of magnets of the non-contact sensor according to the third embodiment. [Figure 14] FIG. 14 is a bottom view of a plurality of magnets and a detection member of the non-contact sensor. DETAILED DESCRIPTION OF THE INVENTION

[0009] In the following embodiments, the non-contact sensor 1 of the present disclosure will be described using the drawings. However, the following embodiments are merely a part of various embodiments of the present disclosure. The following embodiments can be modified in various ways depending on the design, etc., as long as the object of the present disclosure can be achieved. Furthermore, the following embodiments, including modified examples, may be realized by combining them as appropriate. Furthermore, the drawings described in the following embodiments are schematic diagrams, and the ratios of the sizes and thicknesses of the components in the drawings do not necessarily reflect the actual dimensional ratios.

[0010] In each drawing, the X-axis direction is defined as the left-right direction, the Y-axis direction as the front-rear direction (depth direction), and the Z-axis direction as the up-down direction. Furthermore, the positive direction in the X-axis direction is defined as facing right, the positive direction in the Y-axis direction as facing backward, and the positive direction in the Z-axis direction as facing upward. However, these directions are merely examples and are not intended to limit the directions in which the non-contact sensor 1 may be used. Furthermore, the arrows indicating the various directions in the drawings are merely shown for explanatory purposes and have no substance.

[0011] (Embodiment 1) (overview) 1 to 3 are external views of a non-contact sensor 1 of this embodiment. The non-contact sensor 1 detects an object 9. The non-contact sensor 1 includes a housing C1, a detection member 5, and a magnet 6. The housing C1 has a detection surface 310 that faces the object 9. The detection member 5 is disposed inside the housing C1 and above the detection surface 310. The magnet 6 is disposed inside the housing C1 and above the detection member 5. The detection member 5 detects the magnetism generated by the magnet 6. The direction of the magnetic moment of the magnet 6 is along the vertical direction. The magnet 6 is magnetized so that the top surface is the north pole and the bottom surface is the south pole. The magnet 6 has a through-hole 60 that penetrates in the vertical direction (see FIG. 6). When viewed from below, the detection member 5 overlaps with the through-hole 60 (see FIG. 7).

[0012] According to the above configuration, the non-contact sensor 1 detects the change in magnetism that accompanies the movement of the object 9 using the detection member 5, thereby enabling the detection of the object 9. The object 9 is preferably a magnetic body. If the object 9 is a magnetic body, the change in magnetism that accompanies the movement of the object 9 becomes relatively large. Detecting the object 9 means detecting the movement or rotation of the object 9.

[0013] For example, as shown in FIG. 1, when the object 9a moves in the vertical direction and thereby the distance between the object 9a and the detection surface 310 changes, the non-contact sensor 1 can detect the object 9a.

[0014] Furthermore, for example, as shown in FIG. 2, when the positional relationship between the object 9b and the detection surface 310 changes due to the rotation of the object 9b, the non-contact sensor 1 can detect the object 9b.

[0015] Furthermore, for example, as shown in FIG. 3, when the positional relationship between the object 9c and the detection surface 310 changes as the object 9c moves in a direction intersecting the up-and-down direction, the non-contact sensor 1 can detect the object 9c.

[0016] The object 9 is, for example, an in-vehicle part that moves when the driver operates the transmission or clutch. The non-contact sensor 1 is mounted on the automobile to detect, for example, the operation of the transmission or clutch.

[0017] Here, as described above, the detection member 5 overlaps with the through-hole 60 when viewed from below. The magnetic field is weak in the area facing the through-hole 60. Therefore, the magnetic field applied from the magnet 6 to the detection member 5 is weaker than when the through-hole 60 is not present. Therefore, the magnetic field (magnetic flux density) applied to the detection member 5 is less likely to reach the detection limit of the detection member 5. This reduces the possibility that the non-contact sensor 1 will be unable to detect the object 9, and improves the reliability of the non-contact sensor 1.

[0018] Furthermore, even if a magnet 6 with a relatively strong magnetic force is used as the magnet 6, there is a low possibility that the magnetism (magnetic flux density) applied to the detection member 5 will reach the detection limit of the detection member 5. Therefore, it is possible to use a magnet 6 with a relatively strong magnetic force as the magnet 6. By using a magnet 6 with a relatively strong magnetic force as the magnet 6, it becomes possible for the non-contact sensor 1 to detect an object 9 located farther away from the detection surface 310.

[0019] The magnet 6 is preferably a magnet with a stronger magnetic force than a ferrite magnet. Therefore, the magnet 6 is preferably a neodymium magnet. The magnet 6 is also preferably a samarium-cobalt magnet or an alnico magnet.

[0020] (detail) The non-contact sensor 1 of this embodiment will be described in more detail below.

[0021] (1) Overall structure 4 and 5, the non-contact sensor 1 includes a housing C1, a detection member 5, a magnet 6, and further includes a resin member 4 and a substrate 7. Also, as shown in FIGS. 4, 5, and 8, the non-contact sensor 1 includes a plurality of (three in the illustrated example) connection members 11, a plurality of (three in the illustrated example) terminals 12, a first O-ring 81, a second O-ring 82, and a washer 83.

[0022] (2) Housing As shown in FIGS. 4, 5, and 8, the case C1 includes a housing 2 and a cover 3.

[0023] The housing 2 has a cylindrical portion 21 , a flange portion 22 , and a head 23 .

[0024] The cylindrical portion 21 has a cylindrical shape. The axial direction of the cylindrical portion 21 is along the vertical direction. The cylindrical portion 21 has a small diameter portion 210 at the lower end portion of the cylindrical portion 21. The outer diameter of the cylindrical portion 21 is smaller at the small diameter portion 210. The cylindrical portion 21 is provided with a screw thread.

[0025] The flange portion 22 protrudes outward in the radial direction of the cylindrical portion 21 from the upper end portion of the cylindrical portion 21. The flange portion 22 has a polygonal shape.

[0026] The head 23 protrudes upward from the upper end portion of the flange portion 22. The head 23 has a cylindrical shape.

[0027] Next, an example of a method for attaching the non-contact sensor 1 to a target component will be described. The tubular portion 21 is inserted into a hole provided in the target component. Furthermore, a washer 83 is arranged to surround the tubular portion 21. The non-contact sensor 1 is attached to the target component with the washer 83 sandwiched between the lower surface 220 of the flange portion 22 and the target component. In this way, the washer 83 ensures airtightness between the flange portion 22 and the target component.

[0028] Next, we will explain the cover 3. The cover 3 has a cylindrical shape with a bottom. The cover 3 has a bottom 31 including a detection surface 310, a side portion 32 protruding from the bottom 31, and a protrusion 33 protruding from the side portion 32 (see FIG. 11).

[0029] The bottom 31 has a disk-like shape. The thickness direction of the bottom 31 is along the vertical direction. The detection surface 310 is the lower surface of the bottom 31.

[0030] The inner protrusion 311, which is a part of the bottom 31, protrudes upward from the surrounding area. The inner protrusion 311 has a cylindrical shape with a bottom surface at the top. The inner protrusion 311 is provided between the center of the bottom 31 and the peripheral edge.

[0031] The side portion 32 has a cylindrical shape. The axial direction of the side portion 32 is along the vertical direction. The side portion 32 protrudes upward from the peripheral edge of the bottom portion 31.

[0032] The side portion 32 has a mounting groove 321 near the upper end of the side portion 32. The mounting groove 321 is a circular groove provided along the circumferential direction of the side portion 32. A first O-ring 81 is inserted into the mounting groove 321.

[0033] The protrusion 33 (see FIG. 11) protrudes from the inner circumferential surface of the side portion 32 toward the center of the side portion 32. That is, the housing C1 includes the protrusion 33 protruding from the inner circumferential surface of the housing C1. The longitudinal direction of the protrusion 33 is aligned with the up-down direction.

[0034] The cover 3 is attached to the housing 2. More specifically, the upper end of the cover 3 is inserted into the lower end of the housing 2. When the cover 3 is attached to the housing 2, a first O-ring 81 is sandwiched between the bottom surface of the attachment groove 321 of the cover 3 and the inner circumferential surface of the housing 2. This seals the space surrounded by the cover 3 and the housing 2.

[0035] (3) Magnets The magnet 6 is a permanent magnet. As shown in Figures 4 and 6, the shape of the magnet 6 is cylindrical with its axial direction aligned in the vertical direction. That is, the magnet 6 has a through-hole 60 at its center. The through-hole 60 is circular in shape. The through-hole 60 passes through the magnet 6 in the vertical direction.

[0036] The magnet 6 has a first magnetic pole 61 and a second magnetic pole 62. The first magnetic pole 61 is provided above the second magnetic pole 62. The second magnetic pole 62 has a polarity opposite to that of the first magnetic pole 61. In the example shown in FIG. 6, the first magnetic pole 61 is a north pole and the second magnetic pole 62 is a south pole. However, contrary to the illustrated example, the first magnetic pole 61 may be a south pole and the second magnetic pole 62 may be a north pole.

[0037] In Fig. 6, the first magnetic pole 61 is marked with the letter "N" and a dot, and the second magnetic pole 62 is marked with the letter "S." However, the letters "N" and "S" and the dot are displayed only for the purpose of explanation, and the letters and dots are not actually marked on the magnet 6. The same applies to Figs. 12 and 13.

[0038] The magnet 6 is housed in the cover 3. The magnet 6 is integrated with the resin member 4 by insert molding.

[0039] (4) Detection member As shown in FIG. 7, the detection member 5 has a package 51, a plurality of element parts 52 (two in the illustrated example), and a signal processing circuit 53.

[0040] The package 51 is made of, for example, resin and contains a plurality of element units 52 and a signal processing circuit 53.

[0041] Each of the plurality of element units 52 outputs a signal in response to the magnetism generated by the magnet 6. As an example, each of the plurality of element units 52 is a Hall element. That is, as an example, the detection member 5 is a Hall IC.

[0042] The signal processing circuit 53 includes, for example, a semiconductor integrated circuit (IC). The signal processing circuit 53 processes signals output from the plurality of element units 52. The signal processing circuit 53 includes, for example, a comparator to which voltage signals output from the plurality of element units 52 are input, and outputs a high signal or a low signal by comparing the voltage signal with a threshold. Each time a state switches between a state in which the object 9 is approaching the detection surface 310 and a state in which the object 9 is away from the detection surface 310, the signal output from the signal processing circuit 53 switches between a high signal and a low signal.

[0043] The multiple connection members 11 are mechanically and electrically connected to the detection member 5. Each of the multiple connection members 11 is a lead for an electronic component. The multiple connection members 11 include a connection member 11 used as an input terminal of the detection member 5 and a connection member 11 used as an output terminal of the detection member 5. The multiple connection members 11 are drawn out from the detection member 5 in a direction (rearward) intersecting the up-and-down direction.

[0044] 7, when viewed from below, the detection member 5 overlaps with the through-hole 60. Specifically, when viewed from below, the shape of the inner edge 600 of the through-hole 60 is circular, and at least a part of the detection member 5 is disposed inside the inner edge 600.

[0045] Furthermore, when viewed from below, the outer edge 520 of each of the multiple element portions 52 is surrounded by the inner edge 600 of the through-hole 60. In other words, when viewed from below, the entirety of each of the multiple element portions 52 overlaps with the through-hole 60. Therefore, the magnetic field applied from the magnet 6 to the multiple element portions 52 is weaker than when there is no through-hole 60. Furthermore, the magnetic field applied from the magnet 6 to the multiple element portions 52 is weaker than when the multiple element portions 52 overlap with regions of the magnet 6 other than the through-hole 60.

[0046] Moreover, the signal processing circuit 53 overlaps with the through-hole 60 when viewed from below.

[0047] (5) Circuit board The substrate 7 is housed in the housing C1. As shown in Figures 4, 5, and 8, the substrate 7 is, for example, a rigid substrate. The thickness direction of the substrate 7 is along the front-rear direction. The longitudinal direction of the substrate 7 is along the up-down direction. The lateral direction of the substrate 7 is along the left-right direction.

[0048] The substrate 7 is electrically connected to the plurality of connection members 11 and the plurality of terminals 12. The substrate 7 has a plurality of (three in the illustrated example) first through holes 71 into which the plurality of connection members 11 are inserted, and a plurality of (three in the illustrated example) second through holes 72 into which the plurality of terminals 12 are inserted.

[0049] The substrate 7 is electrically connected to the detection member 5 via a plurality of connection members 11.

[0050] The plurality of terminals 12 are electrically connected to an external device. The substrate 7 is electrically connected to the external device via the plurality of terminals 12. The external device is, for example, an ECU (Electronic Control Unit) of an automobile.

[0051] For example, a voltage generating circuit is mounted on the substrate 7. The voltage generating circuit includes, for example, a resistor. The voltage generating circuit generates an output voltage to be output to an external device based on the signal output from the detection member 5.

[0052] The voltage generating circuit also includes, for example, passive components for noise suppression.

[0053] The substrate 7 has a plurality of (two in the illustrated example) positioning portions 73. Each of the positioning portions 73 is a recess. A holding protrusion 48 (described later) of the resin member 4 is inserted into the positioning portion 73, thereby positioning the substrate 7 relative to the resin member 4.

[0054] (6) Resin parts The resin member 4 is a resin molded product. The resin member 4 is a non-magnetic material and has electrical insulation properties.

[0055] As shown in FIGS. 4, 5, and 8, the resin member 4 has a connector housing portion 41, a table 42, a holder 43, a covering portion 44, and a shaft portion 45.

[0056] The connector housing 41 has a cylindrical shape with an axial direction along the vertical direction. When viewed from above, the connector housing 41 has an elliptical shape. When viewed from above, the longitudinal direction of the connector housing 41 is along the left-right direction.

[0057] A plurality of terminals 12, which can be electrically connected to an external device, are fixed to the resin member 4 while penetrating the resin member 4. A first end of each of the plurality of terminals 12 is exposed to the internal space of the connector housing portion 41, and a second end is connected to the board 7. A portion of each of the plurality of terminals 12 between the first end and the second end is embedded in the resin member 4.

[0058] The resin member 4 further has a plurality of ribs 46 protruding from the outer peripheral surface of the connector housing portion 41. The longitudinal direction of the plurality of ribs 46 is aligned with the up-down direction.

[0059] The resin member 4 further has claws 47 protruding from the outer circumferential surface of the connector housing portion 41.

[0060] The table 42 is disk-shaped. The thickness direction of the table 42 is along the up-down direction. A connector housing 41 protrudes from the upper surface of the table 42. A holder 43 protrudes from the lower surface of the table 42.

[0061] When viewed from above, the diameter of the table 42 is longer than the longitudinal length of the connector housing portion 41. When viewed from above, the table 42 protrudes outward from the connector housing portion 41.

[0062] The table 42 is housed in the head 23 of the housing 2. A second O-ring 82 is sandwiched between the table 42 and the head 23. This seals the space surrounded by the resin member 4 and the housing 2.

[0063] The holder 43 is shaped like a plate. The thickness direction of the holder 43 is along the front-rear direction. The longitudinal direction of the holder 43 is along the up-down direction. The substrate 7 is fixed (held) on the front surface of the holder 43. That is, the substrate 7, which is electrically connected to the detection member 5, is fixed to the resin member 4.

[0064] The holder 43 has a plurality of (three in the illustrated example) first insertion holes 431 through which the plurality of connection members 11 are passed, and a second insertion hole 432 through which the plurality of terminals 12 are passed.

[0065] The resin member 4 further has a plurality of (two in the illustrated example) holding protrusions 48 protruding from the front surface of the holder 43. Each holding protrusion 48 is inserted into a positioning portion 73 (recess) of the substrate 7.

[0066] The covering portion 44 is connected to the lower end of the holder 43. The covering portion 44 is a member that covers the magnet 6.

[0067] The covering portion 44 has a cylindrical shape. The axial direction of the covering portion 44 is aligned with the up-down direction. The central axis of the covering portion 44 is located forward of the holder 43.

[0068] The covering portion 44 has an internal space, in which the shaft portion 45 is provided and the magnet 6 is embedded. The shaft portion 45 is cylindrical in shape. The central axis of the shaft portion 45 coincides with the central axis of the covering portion 44. The shaft portion 45 is connected to the covering portion 44.

[0069] The diameter of the shaft portion 45 is equal to the diameter of the through hole 60 of the magnet 6. The shaft portion 45 is embedded in the through hole 60. In this manner, the resin member 4 is disposed inside the through hole 60.

[0070] The resin member 4 is fixed to the housing C1 by, for example, a table 42 and a holder 43. By inserting the shaft portion 45 of such a resin member 4 into the through-hole 60 of the magnet 6, it is possible to suppress displacement of the magnet 6 and stably fix the magnet 6. The resin member 4 is a relatively large member that has a portion that is fixed to the substrate 7, so by inserting such a resin member 4 into the through-hole 60 of the magnet 6, it is possible to stably fix the magnet 6.

[0071] 11, a first cutout portion 441 having a cutout shape is provided on the upper surface of the covering portion 44. In the first cutout portion 441, a part of the magnet 6 is exposed.

[0072] Further, a notched second cutout portion 442 is provided on the side surface of the covering portion 44. The second cutout portion 442 is an annular groove that extends along the circumferential direction of the covering portion 44. A part of the magnet 6 is exposed in the second cutout portion 442.

[0073] The covering portion 44 includes a groove portion 443 on the outer circumferential surface of the covering portion 44. The groove portion 443 is provided at the front end of the covering portion 44. The covering portion 44 is recessed rearward at the groove portion 443.

[0074] The protrusion 33 of the housing C1 is inserted into the groove 443. This positions the resin member 4 in the housing C1.

[0075] 9, the covering portion 44 includes a first supporting portion 444, a second supporting portion 445, and a third supporting portion 446 at the bottom of the covering portion 44. The upper surfaces of the first supporting portion 444, the second supporting portion 445, and the third supporting portion 446 are in contact with the lower surface of the magnet 6. The first supporting portion 444, the second supporting portion 445, and the third supporting portion 446 support the magnet 6.

[0076] The first support portion 444 and the second support portion 445 are aligned on the left and right. The third support portion 446 connects the first support portion 444 and the second support portion 445 together.

[0077] The outer peripheral surfaces of the first support portion 444 and the second support portion 445 are arc-shaped in accordance with the shape of the entire outer peripheral surface of the covering portion 44. When viewed from below, the first support portion 444 and the second support portion 445 are quadrant-shaped.

[0078] The first support portion 444 has a recess 4440. The second support portion 445 has a recess 4450. The recess 4440 and the recess 4450 are aligned on the left and right.

[0079] The first support portion 444 and the second support portion 445 are provided below the magnet 6 and above the detection surface 310. Therefore, the recesses 4440 and 4450 are provided between the magnet 6 and the detection surface 310.

[0080] 10, the detection member 5 is fitted into the recesses 4440 and 4450 of the resin member 4. This fixes the detection member 5 to the resin member 4. More specifically, the package 51 of the detection member 5 has dimensions that allow it to be fitted into the recesses 4440 and 4450. Even more specifically, the shape of the package 51 is rectangular when viewed from below, and two corners of the package 51 are fitted into the recesses 4440 and 4450, respectively.

[0081] Furthermore, the package 51 is fitted into the recesses 4440, 4450 of the resin member 4 and is in contact with the shaft portion 45 of the resin member 4. The package 51 is fixed to the shaft portion 45 of the resin member 4 by, for example, adhesion. The package 51 may also be adhered to the magnet 6.

[0082] A substrate 7 is disposed above the magnet 6, and a detection member 5 is disposed below the magnet 6. That is, the magnet 6 is disposed between the substrate 7 and the detection member 5.

[0083] The multiple connection members 11 electrically connecting the detection member 5 and the substrate 7 are pulled out rearward from the detection member 5 and further extend upward toward the substrate 7. The multiple connection members 11 face the outer surface 63 of the magnet 6 (see FIG. 5). With this configuration, compared to when the connection members 11 are arranged inside the through-hole 60 of the magnet 6, the possibility of the connection members 11 interfering with the magnet 6 when arranging the connection members 11 can be reduced, and damage to the connection members 11 (damage due to bending, etc.) can be suppressed.

[0084] (Modification of the first embodiment) The following are examples of modifications of the first embodiment. The following modifications may be implemented in appropriate combinations. The following modifications can also be applied to the second and third embodiments as appropriate.

[0085] It is preferable that the plurality of element portions 52 of the detection member 5 overlap with the through-hole 60 when viewed from below. Of the detection member 5, for example, at least a part of the signal processing circuit 53 does not have to overlap with the through-hole 60 when viewed from below.

[0086] It is not essential that the resin member 4 is embedded in the through-hole 60, and the inside of the through-hole 60 may be hollow.

[0087] In the resin member 4, the shaft portion 45 and the recesses 4440, 4450 may be provided separately and fixed.

[0088] The magnet 6 is not limited to a permanent magnet, but may also be an electromagnet.

[0089] The element section 52 is not limited to a Hall element, but may be a magnetoresistive effect element such as an anisotropic magnetoresistive effect element or a giant magnetoresistive effect element.

[0090] The number of element portions 52 may be one, or three or more.

[0091] The number of connection members 11 may be one, two, or four or more.

[0092] The number of terminals 12 may be one, two, four or more.

[0093] (Embodiment 2) The non-contact sensor 1 according to the second embodiment will be described below with reference to Fig. 12. The same components as those in the first embodiment will be denoted by the same reference numerals and the description thereof will be omitted.

[0094] The non-contact sensor 1 of this embodiment includes a magnet 6A instead of the magnet 6. The other configurations are the same as those of the first embodiment.

[0095] The magnet 6A is a permanent magnet. The shape of the magnet 6A is cylindrical with its axial direction aligned in the vertical direction. That is, the magnet 6A has a through-hole 60 in its center. The through-hole 60 is circular. The through-hole 60 passes through the magnet 6A in the vertical direction.

[0096] The magnet 6A has multiple magnetic poles. More specifically, the magnet 6A has multiple first magnetic poles 61 and multiple second magnetic poles 62. The second magnetic poles 62 have opposite polarities to the first magnetic poles 61. Specifically, the first magnetic poles 61 are north poles, and the second magnetic poles 62 are south poles.

[0097] On the lower surface 64 of the magnet 6A, different poles of the plurality of magnetic poles are arranged adjacent to each other. More specifically, as shown in Fig. 12, on the lower surface 64 of the magnet 6A, eight magnetic poles are arranged around the through-hole 60, and two magnetic poles adjacent to each other in the direction surrounding the through-hole 60 are different poles. In other words, the first magnetic poles 61 and the second magnetic poles 62 are arranged alternately in the direction surrounding the through-hole 60.

[0098] In this embodiment, by arranging both the north pole and the south pole on the lower surface 64 of the magnet 6A, the magnetic distribution can be limited to the periphery of the magnet 6A, and therefore the detection range of the object 9 (see FIG. 1) by the non-contact sensor 1 can be limited.

[0099] (Embodiment 3) The non-contact sensor 1 according to the third embodiment will be described below with reference to Figures 13 and 14. The same components as those in the first embodiment will be denoted by the same reference numerals and the description thereof will be omitted.

[0100] The non-contact sensor 1 of this embodiment includes a plurality of magnets 6B (eight in the illustrated example) instead of the magnet 6. The other configurations are the same as those of the first embodiment.

[0101] Therefore, the non-contact sensor 1 of this embodiment detects an object 9. The non-contact sensor 1 includes a housing C1, a detection member 5, and multiple magnets 6B. The housing C1 has a detection surface 310 that faces the object 9. The detection member 5 is disposed inside the housing C1 and above the detection surface 310. The multiple magnets 6B are disposed inside the housing C1 and above the detection member 5. The direction of the magnetic moment of each of the multiple magnets 6B is aligned in the vertical direction. The detection member 5 has an element unit 52 that outputs a signal in response to the magnetism generated by the multiple magnets 6B.

[0102] The magnets 6B are permanent magnets. The magnets 6B are cylindrical in shape with their axial direction aligned in the vertical direction. The multiple magnets 6B are arranged in an annular shape when viewed from below.

[0103] Here, the outer surfaces 63 of the multiple magnets 6B when viewed from below are defined as follows: When viewed from below, the surface connecting the outer surfaces of the magnets 6B on the opposite side to the space SP1 surrounded by the multiple magnets 6B is defined as the outer surface 63 of the multiple magnets 6B. In Figure 14, a dashed line representing the outer surface 63 is shown superimposed on the outline of each magnet 6B.

[0104] When viewed from below, the detection member 5 is disposed inside the outer surfaces 63 of the magnets 6B. In other words, the detection member 5 does not protrude beyond the outer surfaces 63 when viewed from below.

[0105] When viewed from below, the magnets 6B do not overlap the element units 52. More specifically, the element units 52 are arranged in a space SP1 surrounded by the magnets 6B. The space SP1 corresponds to the through-hole 60 in the first embodiment.

[0106] In the space SP1 surrounded by the plurality of magnets 6B, for example, a resin member 4 is embedded.

[0107] According to this embodiment, the magnetic field applied to the element unit 52 from the multiple magnets 6B is weaker than when at least one magnet 6B of the multiple magnets 6B overlaps with the element unit 52. Therefore, there is a low possibility that the magnetic field (magnetic flux density) applied to the element unit 52 will reach the detection limit of the element unit 52. This reduces the possibility that the non-contact sensor 1 will be unable to detect the object 9, and improves the reliability of the non-contact sensor 1.

[0108] Furthermore, even if a magnet 6B with a relatively strong magnetic force is used as the magnet 6B, there is a low possibility that the magnetism (magnetic flux density) applied to the element unit 52 will reach the detection limit of the element unit 52. Therefore, a magnet with a relatively strong magnetic force can be used as the magnet 6B. By using a magnet with a relatively strong magnetic force as the magnet 6B, it becomes possible for the non-contact sensor 1 to detect an object 9 located farther away from the detection surface 310.

[0109] 13, a first magnetic pole 61 (north pole) is provided on the upper side of each magnet 6B, and a second magnetic pole 62 (south pole) is provided on the lower side. However, the arrangement of the first magnetic pole 61 and the second magnetic pole 62 can be changed as appropriate. For example, the arrangement of the first magnetic pole 61 and the arrangement of the second magnetic pole 62 may be interchanged. Alternatively, as in the second embodiment, the first magnetic poles 61 and the second magnetic poles 62 may be arranged alternately when viewed from below.

[0110] 14, when viewed from below, a plurality of (eight) magnets 6B are arranged so as to tightly surround the area in which the element section 52 is provided. In contrast to this, for example, the range of the magnetic field lines generated from the plurality of magnets 6B may be limited by omitting some of the plurality of (eight) magnets 6B in the configuration of FIG.

[0111] (summary) The above-described embodiments and the like disclose the following aspects.

[0112] A non-contact sensor (1) according to a first aspect detects an object (9). The non-contact sensor (1) includes a housing (C1), a detection member (5), and a magnet (6; 6A). The housing (C1) has a detection surface (310) that faces the object (9). The detection member (5) is disposed inside the housing (C1) and above the detection surface (310). The magnet (6; 6A) is disposed inside the housing (C1) and above the detection member (5). The detection member (5) detects magnetic fields generated by the magnet (6; 6A). The magnet (6; 6A) has a through-hole (60) that penetrates in the vertical direction. When viewed from below, the detection member (5) overlaps with the through-hole (60).

[0113] According to the above configuration, the magnetic field applied from the magnet (6; 6A) to the detection member (5) is smaller than when the through-hole (60) is not provided. Therefore, the magnetic field (magnetic flux density) applied to the detection member (5) is less likely to reach the detection limit of the detection member (5). This reduces the possibility that the non-contact sensor (1) will be unable to detect the object (9), thereby improving the reliability of the non-contact sensor (1).

[0114] In the non-contact sensor (1) according to the second aspect, the detection member (5) in the first aspect has an element portion (52) that outputs a signal in response to magnetism. The direction of the magnetic moment of the magnet (6; 6A) is along the vertical direction. When viewed from below, the outer edge (520) of the element portion (52) is surrounded by the inner edge (600) of the through-hole (60).

[0115] According to the above configuration, the magnetism (magnetic flux density) applied to the element portion (52) is unlikely to reach the detection limit of the element portion (52).

[0116] In addition, the non-contact sensor (1) according to a third aspect is the non-contact sensor (1) of the first or second aspect, further including a resin member (4) disposed inside the through-hole (60). The detection member (5) is fixed to the resin member (4).

[0117] According to the above configuration, it is possible to prevent misalignment between the detection member (5) and the magnet (6; 6A), thereby improving the detection accuracy of the object (9).

[0118] In the non-contact sensor (1) according to the fourth aspect, the resin member (4) in the third aspect has a recess (4440; 4450) between the magnet (6; 6A) and the detection surface (310). The detection member (5) is fitted into the recess (4440; 4450) of the resin member (4).

[0119] According to the above configuration, it is possible to further suppress misalignment between the detection member (5) and the magnet (6; 6A).

[0120] In addition, the non-contact sensor (1) according to a fifth aspect is the third or fourth aspect, further comprising a terminal (12). The terminal (12) is fixed to the resin member (4) and is electrically connectable to an external device.

[0121] According to the above configuration, since the resin member (4) is a relatively large member, by inserting such a resin member (4) into the through hole (60) of the magnet (6; 6A), the magnet (6; 6A) can be stably fixed.

[0122] In addition, in the non-contact sensor (1) according to a sixth aspect, in any one of the third to fifth aspects, the resin member (4) has a covering portion (44) that covers the magnet (6; 6A). The covering portion (44) has a cylindrical shape. The covering portion (44) includes a groove portion (443) on an outer circumferential surface of the covering portion (44). The housing (C1) includes a protrusion (33) that protrudes from an inner circumferential surface of the housing (C1) and is inserted into the groove portion (443).

[0123] According to the above configuration, the resin member (4) can be positioned relative to the housing (C1).

[0124] In addition, in the non-contact sensor (1) according to a seventh aspect, in any one of the first to sixth aspects, the magnet (6; 6A) has a plurality of magnetic poles. Different poles of the plurality of magnetic poles are arranged adjacent to each other on the lower surface (64) of the magnet (6; 6A).

[0125] According to the above configuration, the distribution of magnetism can be limited to the periphery of the magnet (6; 6A), so that the range in which the non-contact sensor (1) detects the object (9) can be limited.

[0126] A non-contact sensor (1) according to an eighth aspect detects an object (9). The non-contact sensor (1) includes a housing (C1), a detection member (5), and a plurality of magnets (6B). The housing (C1) has a detection surface (310) that faces the object (9). The detection member (5) is disposed inside the housing (C1) and above the detection surface (310). The plurality of magnets (6B) are disposed inside the housing (C1) and above the detection member (5). The detection member (5) has an element unit (52) that outputs a signal in response to magnetism generated by the plurality of magnets (6B). When viewed from below, the detection member (5) is disposed inside outer surfaces (63) of the plurality of magnets (6B). When viewed from below, the plurality of magnets (6B) do not overlap with the element unit (52).

[0127] According to the above configuration, the magnetic field applied to the element portion 52 from the plurality of magnets 6B is weaker than when at least one of the plurality of magnets 6B overlaps with the element portion 52. Therefore, the magnetic field (magnetic flux density) applied to the element portion 52 is less likely to reach the detection limit of the element portion 52. This reduces the possibility that the non-contact sensor 1 will be unable to detect the object 9, thereby improving the reliability of the non-contact sensor 1.

[0128] In addition, the non-contact sensor (1) according to a ninth aspect is any one of the first to eighth aspects, and further includes a substrate (7) electrically connected to the detection member (5), and a connecting member (11) electrically connecting the detection member (5) and the substrate (7). The magnets (6; 6A; 6B) are disposed between the substrate (7) and the detection member (5). The connecting member (11) faces the outer surfaces (63) of the magnets (6; 6A; 6B).

[0129] According to the above configuration, compared to when the connecting member (11) is positioned inside the outer surface (63) of the magnet (6; 6A; 6B), the possibility of the connecting member (11) interfering with the magnet (6; 6A; 6B) when the connecting member (11) is positioned can be reduced, thereby suppressing damage to the connecting member (11) (damage due to bending, etc.).

[0130] In addition, in the non-contact sensor (1) according to a tenth aspect, in any one of the first to ninth aspects, the direction of the magnetic moment of each of the plurality of magnets (6B) is along the vertical direction. The magnets (6; 6A; 6B) are neodymium magnets.

[0131] According to the above configuration, since neodymium magnets with relatively strong magnetic force are used as the magnets (6; 6A; 6B), it becomes possible for the non-contact sensor (1) to detect an object (9) located farther away from the detection surface (310).

[0132] The configurations other than those of the first and eighth aspects are not essential for the non-contact sensor (1) and can be omitted as appropriate. [Explanation of symbols]

[0133] 1. Non-contact sensor 4 Resin parts 5. Detection member 6, 6A, 6B magnet 7. Circuit Board 9 objects 11 Connecting member 12 terminals 33 Protrusion 44 Covering part 52 Element section 60 through holes 63 External surface 64 Bottom surface 310 Detection surface 443 Groove 520 outer edge 600 Common-law marriage 4440, 4450 recess C1 chassis

Claims

1. A non-contact sensor for detecting an object, a housing having a detection surface facing the object; a detection member disposed inside the housing and above the detection surface; a magnet disposed inside the housing and above the detection member; Equipped with the detection member detects the magnetism generated by the magnet, The magnet has a through hole that penetrates in the vertical direction, When viewed from below, the detection member overlaps with the through hole. Non-contact sensor.

2. the detecting member has an element portion that outputs a signal in response to the magnetism, the direction of the magnetic moment of the magnet is along the vertical direction, When viewed from below, the outer edge of the element portion is surrounded by the inner edge of the through hole. The non-contact sensor according to claim 1 .

3. Further, a resin member is provided inside the through hole, The detection member is fixed to the resin member. The non-contact sensor according to claim 1 or 2.

4. the resin member has a recess between the magnet and the detection surface, the detection member is fitted into the recess of the resin member; The non-contact sensor according to claim 3 .

5. The terminal is fixed to the resin member and is electrically connectable to an external device.

5. The non-contact sensor according to claim 3 or 4.

6. the resin member has a covering portion that covers the magnet, The covering portion has a cylindrical shape, the covering portion includes a groove portion on an outer circumferential surface of the covering portion, the housing includes a protrusion that protrudes from an inner circumferential surface of the housing and is inserted into the groove; The non-contact sensor according to any one of claims 3 to 5.

7. the magnet has a plurality of magnetic poles; On the lower surface of the magnet, different poles of the plurality of magnetic poles are arranged adjacent to each other. The non-contact sensor according to any one of claims 1 to 6.

8. A non-contact sensor for detecting an object, a housing having a detection surface facing the object; a detection member disposed inside the housing and above the detection surface; a plurality of magnets disposed inside the housing and above the detection member; the detecting member has an element portion that outputs a signal in response to the magnetism generated by the plurality of magnets, When viewed from below, the detection member is disposed inside outer surfaces of the magnets, When viewed from below, the magnets do not overlap with the element portion. Non-contact sensor.

9. a substrate electrically connected to the detection member; a connection member electrically connecting the detection member and the substrate, the magnet is disposed between the substrate and the detection member, The connecting member faces the outer surface of the magnet. The non-contact sensor according to any one of claims 1 to 8.

10. the direction of the magnetic moment of each of the plurality of magnets is along the vertical direction, The magnet is a neodymium magnet. The non-contact sensor according to any one of claims 1 to 9.

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