JP2017092354A - Electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic apparatus capable of preventing occurrence of exfoliation in the junction surface of a sealing part, a cable and a joint interposed member, while ensuring durability thereof, and especially excellent in the environmental resistance.SOLUTION: An electronic apparatus 1A includes a case 10, a cable 30 pulled out from the case 10, a joint interposed member 40, a cylindrical clamp 50 for holding the cable 30, and a sealing part 60 filling the internal space defined by the case 10 and clamp 50. The cable 30 has a core wire 31, and a sheath 33 covering the core wire 31, and the core wire 31 is not covered with the sheath 33 but exposed at the end of the cable 30. The joint interposed member 40 is joined to the sheath 33 and sealing part 60. The sealing part 60 is composed of epoxy resin, and the joint interposed member 40 is composed of resin having a flexural modulus of 80-210 MPa, and the cable 30 has a hanging oblateness of 0.30-0.71.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an electronic device, and more particularly to an electronic device in which a space inside a case is sealed with a resin and a cable is drawn out from the inside of the case.

  In a specific electronic device, in order to ensure environment resistance, the space inside the case in which the electronic component is accommodated is sealed with a resin having excellent durability such as an epoxy resin. In that case, there is a problem of how to draw out a power cable for supplying power, a signal cable for connecting to an external terminal, and the like from the inside of the case while ensuring environmental resistance.

  Usually, the cables such as the power cable and the signal cable described above are configured to be held by an elastically deformable clamp fitted in an opening provided in the case so that stress applied to the cable is relieved. Has been. However, in the configuration in which the cable is simply held by the clamp, the bonding force between the cable and the sealing portion that seals the space inside the case cannot be secured sufficiently, and peeling occurs at this connection portion. As a result, the environment resistance is poor.

  Therefore, various methods for improving the bonding force between the cable and the sealing portion have been studied. For example, Japanese Unexamined Patent Application Publication No. 2015-177042 (Patent Document 1) and Japanese Unexamined Patent Application Publication No. 2009-43429 (Patent Document 2). Discloses a method of improving a bonding force between a cable and a sealing portion provided in a proximity sensor that detects the presence or position of a metal body using a magnetic field.

  In the proximity sensor disclosed in Patent Document 1, a ring cord made of polybutylene terephthalate (PBT) resin is formed by insert molding so as to cover an end of a cable made of polyvinyl chloride (PVC) resin. By forming the sealing portion in a state where the ring cord is press-fitted into the clamp, a bonding force between the cable and the sealing portion is secured by the ring cord.

  In the proximity sensor disclosed in Patent Document 2, a two-color molded member made of polyurethane (PUR) resin and PBT resin is formed by insert molding so as to cover the end of the cable. By providing an inverted frustoconical protrusion at the tip of the two-color molded member and forming the sealing portion in a state in which the two-color molded member is press-fitted into the clamp, the two-color molded member causes a gap between the cable and the sealing portion. Bonding force is secured.

Japanese Patent Laying-Open No. 2015-177042 JP 2009-43429 A

  The configurations disclosed in Patent Documents 1 and 2 are both joining intervening members that intervene between the durability of the cable itself and the joining between the cable and the sealing portion (that is, the above-described ring cord and two-color molded member). Structural improvements have been made to increase the bonding force at the bonding surface between the sealing portion and the bonding intervening member and the bonding surface between the bonding intervening member and the cable while improving the durability of itself.

  Here, under a normal use environment, even when stress is applied to the above-described joint surface, the improvement of the joint force by the above-described structural device does not immediately cause damage to the electronic device. However, in a relatively harsh environment where the temperature change with time is severe and a large amount of oil such as cutting oil is used, the above-described configuration has sufficient bonding force to prevent delamination. Is not obtained, and peeling occurs on the joint surface due to the stress, and liquid such as moisture, oil, or chemical liquid enters from the portion where the peeling occurs and reaches the conductive part, thereby damaging the electronic device. There was a case.

  Therefore, the present invention has been made to solve the above-described problems, and while ensuring the durability of the sealing portion, the cable, and the joining interposition member, it is possible to prevent the occurrence of peeling at these joining surfaces. An object is to provide an electronic device that is particularly excellent in environmental performance.

  In the electronic device in which the space inside the case is sealed with resin, and the cable is drawn out from the inside of the case, the inventors of the present invention have the following advantages: Focusing on the fact that the bonding force at these bonding surfaces is correlated with the hardness (softness) of the sealing portion, the bonding member and the cable itself, the present invention has been completed.

  That is, the electronic device according to the present invention has a case provided with an opening, an electronic component accommodated in the case, and one end electrically connected to the electronic component by being inserted into the opening. The other end of the cable is drawn to the outside of the case, a joining interposition member attached to the cable, and fitted into the opening, and the joining interposition member is fitted into the cable. And a sealing part that fills an internal space defined by the case and the clamp. The cable includes a core wire including a conductive wire and a sheath covering the core wire, and the core wire is exposed at a portion on the one end side of the cable without being covered by the sheath. The joining interposed member is joined to the sheath and joined to the sealing portion. The sealing portion is made of an epoxy resin, and the bonding interposed member is made of a resin having a flexural modulus of 80 MPa to 210 MPa. The cable has a total length of 500 mm and is connected to both ends of the cable to form a loop. A rod is inserted inside the cable to suspend it, and a load of 1.5 N is applied to the lower end of the cable. When the inner diameter along the vertical direction in the outer shape when applied is a and the inner diameter along the horizontal direction is b, the hanging flatness expressed by (ab) / a is 0. It is composed of 30 or more and 0.71 or less.

  In this way, the joining interposition member is made of a resin having a flexural modulus of 80 MPa or more and 210 MPa or less, and the cable is made of a material having a hanging flatness ratio of 0.30 or more and 0.71 or less. Since the member and the cable are composed of a member having an appropriate hardness, it is possible to provide a joining member and cable having high durability in which not only moisture but also liquid such as oil and chemicals hardly penetrate. Further, the sealing portion is made of epoxy resin, the joining interposed member is made of resin having a flexural modulus of 80 MPa to 210 MPa, and the cable has a flattening ratio of 0.30 to 0.71. Since the joining interposition member is composed of a moderately soft member, the joining surface between the sealing portion and the joining interposition member and the joining surface between the joining interposition member and the cable are sufficient. Bonding force is obtained, and it is possible to prevent peeling at these bonding surfaces. Therefore, while ensuring the durability of the sealing portion, the cable, and the joining intervening member, it is possible to provide an electronic device that is particularly excellent in environmental resistance that can prevent peeling at these joining surfaces.

  In the electronic apparatus according to the present invention, it is preferable that the joining interposed member and the sheath are made of the same resin.

  Thus, by comprising the joining interposition member and the sheath with the same resin, the joining interposition member can be easily joined to the cable, and a clear interface is not formed during the joining. Thus, it is possible to obtain an effect in which peeling does not easily occur in the portion.

  In the electronic apparatus according to the present invention, it is preferable that the joining interposed member is made of a fluorine-based resin.

  By constituting the joining interposition member with a fluorine-based resin, it becomes possible to give the joining interposition member high durability in which not only moisture but also liquid such as oil and chemicals hardly penetrate.

  In the electronic apparatus according to the present invention, the sheath is preferably made of a fluorine-based resin.

  Thus, by configuring the sheath of the cable with the fluorine-based resin, it is possible to provide the cable with high durability that is difficult to penetrate not only moisture but also liquid such as oil and chemicals.

  In the electronic apparatus according to the present invention, it is preferable that both the joining interposed member and the sheath are made of a fluorine-based resin.

  In this way, the sheath of the joining interposition member and the cable is made of a fluororesin, so that it is possible to give the joining interposition member and the cable high durability in which not only moisture but liquid such as oil and chemicals hardly penetrate. In addition, a clear interface is not formed at the time of joining, and an effect is obtained in which peeling does not easily occur in the portion.

  In the electronic apparatus according to the present invention, the joining intermediate member covers the outer peripheral surface of the sheath so as to join the sheath, and the tube projecting toward the one end of the cable. In that case, the inner peripheral surface and the outer peripheral surface of the protruding portion and the end surface on the tip side in the axial direction of the protruding portion are all covered with the sealing portion. Accordingly, it is preferable that the sealing portion is bonded to the protruding portion.

  In this way, a cylindrical projecting portion is provided on the joint member, and the inner peripheral surface and outer peripheral surface of the projecting portion and the end surface on the tip end side in the axial direction of the projecting portion are both covered with the sealing portion, thereby sealing. Since the resin amount of the sealing part at the end of the stop part on the side of the joining intervening member is reduced, the residual stress generated when the sealing part is cured can be reduced, and the sealing part of the sealing part accompanying the change in environmental temperature can be reduced. During expansion and contraction, the protrusions follow and elastically deform, and the stress generated inside is greatly relieved. Therefore, a high bonding force between the cable and the sealing portion can be ensured, so that an electronic device having excellent environmental resistance can be obtained.

  In the electronic apparatus according to the present invention, the joining interposed member may be welded to the sheath.

  As described above, by welding the joining interposition member to the sheath, the joining interposition member can be easily joined to the cable, and by melting these surfaces, the joining interposition member and the sheath are integrated. Since a clear interface is not formed between them, an effect is obtained in which peeling does not easily occur in the portion.

  According to the present invention, it is possible to provide an electronic device particularly excellent in environmental resistance capable of preventing the occurrence of peeling on the joint surface while ensuring the durability of the sealing portion, the cable, and the joint member. It becomes possible.

It is a perspective view of the proximity sensor in Embodiment 1 of the present invention. It is sectional drawing along the II-II line | wire shown in FIG. It is an expanded sectional view of the area | region III shown in FIG. It is a schematic perspective view of the cable shown in FIG. 1 and the joining interposition member fixed to this. It is a schematic diagram for demonstrating the measuring method of the hanging flatness ratio of a cable. It is a flowchart for demonstrating the manufacturing method of the proximity sensor in Embodiment 1 of this invention. It is an assembly drawing for demonstrating the manufacturing method of the proximity sensor in Embodiment 1 of this invention. In the proximity sensor in Embodiment 1 of this invention, it is a schematic cross section for demonstrating the reason why high joint force can be ensured in the connection part of the cable with respect to a case, and the front view of the cable to which the joining interposition member was fixed. It is an expanded sectional view of the area | region IX shown in FIG. It is a principal part expanded sectional view of the proximity sensor which concerns on a 1st modification. It is a principal part expanded sectional view of the proximity sensor which concerns on a 2nd modification. It is a principal part expanded sectional view of the proximity sensor which concerns on a 3rd modification. It is a principal part expanded sectional view of the proximity sensor which concerns on a 4th modification. It is a principal part expanded sectional view of the proximity sensor which concerns on a 5th modification. It is a flowchart for demonstrating the manufacturing method of the proximity sensor in Embodiment 2 of this invention. It is an assembly drawing for demonstrating the manufacturing method of the proximity sensor in Embodiment 2 of this invention. It is a table | surface which shows the test conditions and test result of a verification test.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the embodiment described below, a case where the present invention is applied to a proximity sensor will be described as an example. In the following embodiments, the same or common parts are denoted by the same reference numerals in the drawings, and description thereof will not be repeated.

(Embodiment 1)
1 is a perspective view of a proximity sensor according to Embodiment 1 of the present invention, and FIG. 2 is a cross-sectional view taken along line II-II shown in FIG. 3 is an enlarged cross-sectional view of a region III shown in FIG. 2, and FIG. 4 is a schematic perspective view of the cable shown in FIG. 1 and a joint member fixed thereto. FIG. 5 is a schematic diagram for explaining a method of measuring the cable hanging flatness. First, the configuration of the proximity sensor 1A according to the present embodiment will be described with reference to FIGS.

  As shown in FIGS. 1 and 2, the proximity sensor 1 </ b> A as the electronic device in the present embodiment has a substantially cylindrical outer shape, and includes a case 10 and a detection unit set including a first sealing portion 26. A solid body 20, a cable 30, a joining interposed member 40, a clamp 50, and a second sealing portion 60 are provided.

  The case 10 is made of a metal long cylindrical member that is open at both ends, and has a front end portion and a rear end portion in the axial direction. A detector assembly 20 is assembled to the front end of the case 10, and a clamp 50 is assembled to the rear end of the case 10.

  As shown in FIG. 2, the detection unit assembly 20 mainly includes a core 21, a detection coil 22, a coil case 23, a circuit board 24, and a first sealing unit 26.

  The core 21 is made of a short cylindrical member made of a magnetic material. The detection coil 22 is configured in a substantially cylindrical shape by, for example, winding a lead wire, and is accommodated in an annular recess provided on the front end surface of the core 21. A support groove 21 a that supports the front end portion of the circuit board 24 is provided on the rear end surface of the core 21.

  The coil case 23 is composed of a bottomed cylindrical insulating member, and the core 21 and the detection coil 22 are accommodated therein. The front end surface of the core 21 is in contact with the bottom of the coil case 23. The coil case 23 is press-fitted into the case 10 and fixed so that the bottom portion thereof is positioned at the front end of the case 10.

  The circuit board 24 is disposed behind the core 21 so as to extend along the axial direction of the case 10. The circuit board 24 has conductive patterns formed on the front and back surfaces thereof, and various electronic components 25a to 25c and the like are mounted at predetermined positions on the front and back surfaces. The detection coil 22 is electrically connected to the circuit board 24 via a pin attached to the end of the detection coil 22 described above.

  Here, among the various electronic components 25a to 25c mounted on the circuit board 24, the electronic component 25c mounted on the rear end portion of the circuit board 24 is a light emitting element that emits light when energized. The light emitting element emits light according to the operation state of the proximity sensor 1A, and is configured by, for example, an LED (Light Emitting Diode).

  Various processing circuits are formed on the circuit board 24. The processing circuit includes an oscillation circuit having the detection coil 22 as a resonance circuit element, and a discrimination circuit that binarizes the oscillation amplitude of the oscillation circuit with a threshold value. The circuit board 24 is also provided with an output circuit that converts the output of the discrimination circuit into a voltage output or a current output of a predetermined specification, and a power supply circuit that converts the power introduced from the outside into a predetermined power supply specification and outputs it. It has been. In addition, the circuit board 24 is also provided with a light emitting element driving circuit for controlling the driving of the electronic component 25c which is the light emitting element described above.

  These various circuits are constituted by the conductive pattern provided on the circuit board 24, the above-described various electronic components 25a to 25c, the detection coil 22, and the like.

  The first sealing portion 26 seals the core 21, the detection coil 22, and the front end portion of the circuit board 24 housed in the coil case 23. The first sealing portion 26 protects the core 21, the detection coil 22, and the front end portion of the circuit board 24, and seals them from the outside in an air-tight and liquid-tight manner.

  The first sealing portion 26 is formed by injecting a liquid resin into the coil case 23 and curing it. In addition, as a material of this 1st sealing part 26, an epoxy resin, PUR resin, etc. can be utilized suitably, for example.

  A land 24a to which a conductive wire 31a included in a core wire 31 of a cable 30 to be described later is connected is provided at a predetermined position at the rear end portion of the circuit board 24. For example, solder (not shown) is used to connect the lands 24a and the conductive lines 31a.

  The cable 30 is composed of a composite cable including a core wire 31 including a conductive wire 31a, a shield material 32 covering the core wire 31, and a sheath 33. The cable 30 is disposed so as to be inserted into the opening on the rear end side provided in the case 10, and one end of the cable 30 is electrically connected to the various circuits described above by being connected to the circuit board 24 described above. And the other end is pulled out. The cable 30 is made of a cable having a predetermined hanging flatness ratio described later. The sheath 33 is made of resin, and more preferably made of fluorine resin.

  Here, at one end of the cable 30 described above, the shield member 32 and the sheath 33 are peeled off so that the core wire 31 is exposed, and a conductive wire is further provided at a portion connected to the land 24a of the core wire 31. The covering material of the core wire 31 is also peeled off so that 31a is exposed.

  As shown in FIGS. 2 to 4, the joining interposition member 40 is a member for ensuring the joining property between the cable 30 and the second sealing portion 60, and is a sheath positioned on the one end side of the cable 30. 33 is attached to the end.

  The joining interposition member 40 includes a cylindrical base 41 that covers the outer peripheral surface of the end of the sheath 33 located on the one end side of the cable 30 in the internal space defined by the case 10 and the clamp 50, and the one end of the cable 30. It has a cylindrical projecting portion 42 that is located on the one end side of the cable 30 relative to the end portion of the sheath 33 that is located on the side and projects so as to extend along the extending direction of the cable 30. The joining intervention member 40 is attached to the cable 30 so that at least a part of the joining intervention member 40 enters the internal space defined by the case 10 and the clamp 50. The protruding portion 42 is configured to be sufficiently thin, and is preferably configured to be thinner than a portion of the base portion 41 excluding a welded portion 41a described later (that is, a non-welded portion of the base portion 41). In addition, the joining interposed member 40 consists of resin which has the predetermined bending elastic modulus mentioned later, More preferably, it consists of fluorine resin.

  Here, in the present embodiment, the base 41 extends from the end of the sheath 33 located on the one end side of the cable 30 by a predetermined length further toward the one end side of the cable 30, The protruding portion 42 described above is provided so as to further protrude from the tip of the portion protruding from the end portion of the sheath 33 of the base portion 41.

  Further, in the present embodiment, the outer shape of the protruding portion 42 is configured to be smaller than the outer shape of the base portion 41 when viewed along the extending direction of the cable 30. By configuring in this way, the configuration of the clamp 50 described later can be simplified, and accordingly, the outer shape of the connection portion of the cable 30 to the case 10 can be reduced.

  A welding portion 41 a is formed at the rear end portion of the base portion 41. The welded portion 41a is a portion formed by fixing the joining interposed member 40 to the cable 30 by welding, and is thinner than the thickness of the base portion 41 of the portion excluding the welded portion 41a. As described above, the base 41 is welded to the sheath 33, so that the joint member 40 is fixed to the cable 30 so as not to move.

  A groove portion 43 extending in the circumferential direction is provided at a predetermined position on the outer peripheral surface of the protruding portion 42. The groove 43 is a concavo-convex part provided to increase the bonding force between a second sealing part 60 and a bonding interposition member 40, which will be described later. By providing the groove 43 in the protruding part 42, a so-called anchor effect is obtained. Is obtained and the bonding force is improved. The anchor effect is an effect in which the unevenness becomes a wedge and the bonding force is improved by providing unevenness on the joint surface.

  As shown in FIGS. 2 and 3, the clamp 50 has a substantially cylindrical shape, and the cable 30 is inserted through the clamp 50. The clamp 50 is fitted in the opening on the rear end side provided in the case 10, and holds the cable 30 by fitting the above-described joining interposed member 40 to the rear end portion of the clamp 50. ing. The clamp 50 is made of a resin member so as to be elastically deformable, and is for reducing stress applied to the cable 30 and stress applied to the joining interposed member 40.

  More specifically, the clamp 50 is located between the cylindrical fixing portion 51 located at the front end portion, the substantially cylindrical holding portion 52 located at the rear end portion, and the fixing portion 51 and the holding portion 52. The connecting portion 53 that connects the fixing portion 51 and the holding portion 52 is included.

  The fixing part 51 is a part for fixing the clamp 50 to the case 10 by being press-fitted into an opening on the rear end side provided in the case 10. The holding part 52 is a part for holding the bonding interposition member 40 by press-fitting the bonding interposition member 40 therein. Further, the connecting portion 53 secures the distance between the fixing portion 51 and the holding portion 52 by a predetermined distance, thereby enhancing the function of mitigating the stress applied to the cable 30 and the stress applied to the joining interposed member 40 described above. It is a part.

  Further, in order to fill the internal space defined by the case 10 and the clamp 50 into the predetermined position of the connecting portion 53, a liquid resin that becomes the second sealing portion 60 is injected. A gate 53a is provided for use.

  In the present embodiment, the clamp 50 is made of a non-light-shielding resin material. This is for projecting light emitted from the electronic component 25c as the light emitting element to the outside via the clamp 50. Therefore, a portion of the fixing portion 51 facing the light emitting element has a predetermined amount. A light guide 53b having a shape is provided.

  The second sealing portion 60 fills the space excluding the space sealed by the first sealing portion 26 described above, among the internal spaces defined by the case 10 and the clamp 50. As a result, the portion of the circuit board 24 excluding the front end portion described above, the various electronic components 25a to 25c mounted on the portion, and the core wire 31 of the portion not covered by the sheath 33 of the cable 30 are 2 is sealed by the sealing portion 60.

  The second sealing portion 60 is a portion of the circuit board 24 other than the above-described front end portion, and various electronic components 25 a to 25 c mounted on the portion, and a portion not covered by the sheath 33 of the cable 30. The core wire 31 is protected, and these are hermetically sealed from the outside.

  As described above, the second sealing portion 60 is formed by injecting a liquid resin through the gate 53a of the clamp 50 and curing it. Note that an epoxy resin is used as the material of the second sealing portion 60.

  Here, as shown in FIG. 3, the projecting portion 42 of the joining interposed member 40 is covered with the second sealing portion 60 on the inner peripheral surface, the outer peripheral surface, and the end surface on the distal end side in the axial direction. Yes. Thereby, in the proximity sensor 1A in the present embodiment, the bonding force between the cable 30 and the second sealing portion 60 is ensured higher than that of the conventional proximity sensor. The mechanism will be described later.

  In the proximity sensor 1A in the present embodiment described above, as described above, the second sealing portion 60 is made of a highly durable epoxy resin, and various types of housings are accommodated in the case 10 thereby. The electronic parts are airtight and liquid tightly protected. Further, in the proximity sensor 1A according to the present embodiment, the cable 30 and the joining interposition member 40 described above have sufficient durability with respect to not only moisture but also liquids such as oil and chemicals, and joint portions ( That is, moderate hardness is obtained so that sufficient bonding force can be obtained at the bonding surface between the second sealing portion 60 and the bonding interposed member 40 and the bonding surface between the bonding interposed member 40 and the sheath 33 of the cable 30. It is comprised by the member of (softness).

  Generally, the level of durability of a resin correlates with the cross-linking density of the resin. The higher the cross-linking density, the higher the durability, and the lower the cross-linking density, the lower the durability. This is because when the molecular chains constituting the resin are more and more crosslinked, the molecular level space where the liquid molecules can enter is small and less, so that the liquid molecules are difficult to permeate. This is due to the increased durability.

  In addition, the magnitude of the crosslink density of the resin correlates with the magnitude of the elastic modulus of the resin. The higher the crosslink density, the greater the elastic modulus and the more difficult the elastic deformation. It becomes smaller and more easily elastically deformed.

  Therefore, in general, the level of durability of a resin correlates with the magnitude of the elastic modulus of the resin. The higher the elastic modulus (that is, the harder the resin that is hard to be elastically deformed), the higher the durability and the elastic modulus is. It can be said that the smaller the value (that is, the softer the resin that is easily elastically deformed), the lower the durability.

  On the other hand, the magnitude of the joining force at the joint surface between the resins also correlates with the elastic modulus of the resin constituting the joint surface, and the larger the elastic modulus (that is, the harder resin that is hard to be elastically deformed), the smaller the joining force is. Thus, the smaller the elastic modulus (that is, the softer the resin that is more easily elastically deformed), the greater the bonding force. This is because, when an external stress or an internal stress accompanying thermal history is applied to the joint surface, the stress applied to the joint surface is reduced as the elastic modulus is smaller.

  Thus, since the level of durability of the resin and the magnitude of the bonding force at the bonding surface between the resins are in a so-called trade-off relationship, in the present embodiment, based on the result of the verification test described later, The hardness of the joint member 40 and the cable 30 is determined based on an index described later.

  In the proximity sensor 1A according to the present embodiment, the joining interposed member 40 is made of a resin having a flexural modulus of 80 MPa to 210 MPa. Here, the flexural modulus is an index representing the hardness of the material itself. The smaller the flexural modulus, the greater the strain due to stress and the harder the material is that it is difficult to elastically deform. Here, in the present embodiment, as described above, the bonding interposition member 40 is made of a fluorine-based resin, but the bending elastic modulus of the fluorine-based resin varies depending on its specific composition, It can be included in the above range.

  Thus, since the joining interposition member 40 is composed of a member having an appropriate hardness by constituting the joining interposition member 40 with a resin having a flexural modulus of 80 MPa or more and 210 MPa or less, not only moisture but also oil content can be obtained. It can be set as the joining interposition member 40 provided with the high durability which liquids, such as a chemical | medical solution and it cannot penetrate easily.

  In addition, as described above, the second sealing part 60 is made of epoxy resin, and the joining interposed member 40 is made of a resin having a bending elastic modulus of 80 MPa or more and 210 MPa or less, so that the joining interposed member 40 is moderate. Since it is composed of a soft member, a sufficient bonding force can be obtained at the bonding surface between the second sealing portion 60 and the bonding intervening member 40, and the occurrence of peeling at the bonding surface can be prevented. it can.

  On the other hand, in the proximity sensor 1A in the present embodiment, the cable 30 is configured with a hanging flatness ratio described later of 0.30 or more and 0.71 or less. Here, the hanging flatness ratio is an index representing the hardness of the long member, and indicates that the larger the hanging flatness ratio, the softer the member that is more easily elastically deformed. Here, in the present embodiment, as described above, the sheath 33 of the cable 30 is made of fluororesin, but the hanging flatness ratio of the cable in which the sheath 33 is made of fluororesin is Although it varies depending on the specific configuration, it can be included in the above range.

  As shown in FIG. 5, when measuring the hanging flatness ratio of the cable 30, first, the total length of the cable 30 to be measured is set to 500 mm, and both ends thereof are connected to form a loop shape. Next, the loop-shaped cable 30 is suspended by the rod 100 by inserting the rod 100 inside the loop-shaped cable 30. Further, a weight 110 is attached to the lower end portion of the loop-shaped cable 30 that is suspended by the rod 100, and a load of 1.5N is applied to the lower end portion of the cable 30 vertically downward by the weight 110. .

  As a result, the outer shape of the loop-shaped cable 30 has a flat shape that is long in the vertical direction and short in the horizontal direction, but the hanging flatness is in the vertical direction of the loop-shaped cable 30 in this state. Using the inner diameter (major axis) a and the inner diameter (minor axis) b along the horizontal direction, it is obtained by (ab) / a.

  As described above, since the cable 30 is composed of a member having a moderate hardness by configuring the cable 30 with a hanging flatness ratio of 0.30 or more and 0.71 or less. It can be set as the joining interposition member 40 provided with high durability in which liquids, such as oil and a chemical | medical solution, do not osmose | permeate easily.

  Further, as described above, the joining interposition member 40 is made of a resin having a flexural modulus of 80 MPa to 210 MPa, and the cable 30 is made of a material having a hanging flatness of 0.30 to 0.71. As a result, since the joining interposition member 40 and the cable 30 are composed of moderately soft members, a sufficient joining force can be obtained at the joining surface between the joining interposition member 40 and the cable 30. It is possible to prevent peeling on the surface.

  Therefore, by using the proximity sensor 1A according to the present embodiment, it is possible to prevent the occurrence of peeling on the joint surfaces while ensuring the durability of the second sealing portion 60, the cable 30, and the joint interposed member 40. A proximity sensor having particularly excellent environmental resistance can be obtained.

  In addition, when the joining interposed member 40 is comprised with resin whose bending elastic modulus is less than 80 Mpa, the said joining interposed member 40 will be inferior to durability in a comparatively severe environment, oil content and If a liquid such as a chemical solution penetrates, the proximity sensor 1A may be damaged. On the other hand, when the bonding interposition member 40 is made of a resin having a bending elastic modulus exceeding 210 MPa, in a relatively severe environment, the bonding surface between the second sealing portion 60 and the bonding interposition member 40, and Separation is likely to occur on the joint surface between the joint member 40 and the sheath 33 of the cable 30, and moisture, oil, chemicals, etc. enter the inside and cause a failure of the proximity sensor 1 </ b> A.

  Further, when the cable 30 is configured with a hanging flatness ratio exceeding 0.71, the cable 30 is inferior in durability in a relatively severe environment, so that an oil or chemical solution is used. If the liquid such as the liquid penetrates, the proximity sensor 1A may be damaged. On the other hand, in the case where the cable 30 is configured with a hanging flatness ratio of less than 0.30, in a relatively severe environment, peeling occurs at the joint surface between the joint interposing member 40 and the sheath 33 of the cable 30. It becomes easy to generate | occur | produce, a water | moisture content, oil content, a chemical | medical solution, etc. penetrate | invade into an inside, and cause the failure of proximity sensor 1A.

  In addition, in the proximity sensor 1A according to the present embodiment, as described above, the joining interposed member 40 and the sheath 33 of the cable 30 are made of the same resin, ie, a fluorine-based resin. As described above, the joining interposition member 40 and the sheath 33 are made of the same resin, so that when the joining interposition member 40 is joined (welded) to the sheath 33, the surfaces of the joining interposition member 40 and the sheath 33 are melted. And the sheath 33 are integrated, and as a result, a clear interface is hardly generated. Therefore, if the said structure is employ | adopted, the effect which becomes difficult to generate | occur | produce peeling in the said connection part by not forming an interface can also be acquired.

  FIG. 6 and FIG. 7 are a flow diagram and an assembly diagram for explaining the manufacturing method of the proximity sensor in the present embodiment, respectively. Next, with reference to these FIG. 6 and FIG. 7, the manufacturing method of the proximity sensor 1A in the present embodiment will be described.

  First, as shown in FIG. 6, the joining interposition member 40 is manufactured (process ST11). More specifically, the joining interposition member 40 is formed so as to have a cylindrical base 41 and a cylindrical protrusion 42 extending from the base 41. Various methods, such as injection molding, can be applied to the production of the joint member 40.

  Next, as shown in FIGS. 6 and 7A, the joint member 40 is attached to the cable 30 (step ST12). More specifically, the joining intermediate member 40 is attached to the cable 30 by press-fitting the base 41 of the joining intervention member 40 to the end of the sheath 33 of the cable 30. As a result, the outer peripheral surface of the end portion of the sheath 33 is covered with the base portion 41, and the protruding portion 42 is positioned so as to extend from the base portion 41.

  Next, as shown in FIGS. 6 and 7B, the joint member 40 is welded to the cable 30 (step ST13). More specifically, when heat is applied from the outside to the base portion 41 of the portion press-fitted into the sheath 33, the portion (that is, the portion indicated by the arrow A in FIG. 7B) is thermally welded. In addition to welding by heat conduction, welding by laser irradiation or the like can be used for welding.

  Next, as shown in FIGS. 6 and 7C, the cable 30 is connected to the detector assembly 20 (step ST14). More specifically, the exposed conductive wire 31a of the cable 30 is disposed so as to face the land 24a of the circuit board 24. In this state, these soldering is performed.

  Next, as shown in FIGS. 6 and 7D, the detection unit assembly 20 is assembled to the case 10 (step ST15). More specifically, the detection unit assembly 20 is assembled to the case 10 by press-fitting the detection unit assembly 20 into the front end portion of the case 10.

  Next, as shown in FIG. 6 and FIG. 7E, the clamp 50 is assembled to the case 10 and the joining interposed member 40 (step ST16). More specifically, the fixing portion 51 of the clamp 50 is press-fitted into the opening on the rear end side of the case 10, and the base portion 41 of the joining interposed member 40 is press-fitted into the rear end portion of the clamp 50, thereby And the clamp 50 is assembled | attached to the joining interposition member 40. FIG.

  Next, as shown in FIG. 6, a liquid resin is injected into the case 10 and the clamp 50, and this is cured (step ST17). More specifically, liquid resin is injected from the portion indicated by an arrow B in FIG. 7E through the gate 53a of the clamp 50, and the liquid resin is cured, whereby the proximity sensor 1A having the above-described configuration is obtained. Will be obtained.

  In the above, the case where the joining interposition member 40 is welded to the cable 30 after the joining interposition member 40 is attached to the cable 30 and before the cable 30 is connected to the detection unit assembly 20. Although illustrated, the joining interposition member 40 may be welded to the cable 30 after the cable 30 is connected to the detection unit assembly 20 or after the detection unit assembly 20 is assembled to the case 10. That is, step ST13 may be performed between step ST14 and step ST15, or may be performed between step ST15 and step ST16.

  Furthermore, in the above, after the cable 30 is connected to the detection unit assembly 20 and before the clamp 50 is assembled to the case 10 and the joint member 40, the detection unit assembly 20 is attached to the case 10. Although the case of being assembled is illustrated, the detection unit assembly 20 may be assembled to the case 10 before the cable 30 is connected to the detection unit assembly 20. That is, step ST15 may be performed before step ST14.

  FIGS. 8A and 8B are a schematic cross-sectional view for explaining the reason why a high bonding force can be secured in the connection portion of the cable to the case in the proximity sensor according to the present embodiment, and the bonding, respectively. It is a front view of the cable with which the interposition member was fixed. FIG. 9 is an enlarged cross-sectional view of the region IX shown in FIG. Next, with reference to these FIG. 8 and FIG. 9, in the proximity sensor 1 </ b> A in the present embodiment, the reason why a higher bonding force can be ensured by providing the protruding portion 42 having the above-described configuration on the bonding interposed member 40 will be described. To do. In FIG. 8A, the structure of the clamp 50 is simplified for easy understanding.

  8A and 8B, as described above, in proximity sensor 1A according to the present embodiment, a joining intervening member provided to cover the end of sheath 33 of cable 30 40 is provided with a substantially cylindrical projecting portion 42 which is configured to protrude from the end portion of the sheath 33 and is configured to be sufficiently thin. The inner and outer peripheral surfaces of the projecting portion 42 and the projecting portion are provided. The end surface on the distal end side in the axial direction of the portion 42 is covered with the second sealing portion 60.

  By configuring in this way, firstly, the residual stress generated when the second sealing portion 60 is cured can be reduced. This is because the resin amount of the second sealing portion 60 at the end portion of the second sealing portion 60 on the side of the joining interposed member 40 is reduced by the amount of the protruding portion 42.

  Therefore, the joining force can be maintained high as much as the residual stress is low, and as a result, a high joining force can be secured at the connection portion of the cable 30 to the case 10.

  Secondly, the followability of the protrusion 42 can be ensured when the second sealing portion 60 expands and contracts due to a change in the environmental temperature. This is because the protrusion 42 follows the expansion and contraction of the second sealing portion 60 by an amount corresponding to the thin thickness of the protrusion 42 which is a portion to be bonded to the second sealing portion 60 of the bonding interposed member 40. This is because elastic deformation is allowed.

  More specifically, when the second sealing portion 60 contracts, as shown by an arrow C in FIG. 8A, the end portion of the interface between the joining interposed member 40 and the second sealing portion 60 In this case, a large stress is applied, but at this time, the protrusion 42 follows the direction of the arrow D shown in the drawing and elastically deforms, so that the stress applied to the end is greatly increased. It will be relieved and it can control that exfoliation occurs in the interface concerned.

  Therefore, when the second sealing portion 60 expands and contracts, the joining force can be maintained high as much as the stress applied to the interface between the joining interposed member 40 and the second sealing portion 60 is reduced. As a result, a high bonding force can be secured at the connection portion of the cable 30 to the case 10.

  By adopting the structure, this also leads to an increase in the room for selecting materials for the joining interposed member 40 and the second sealing portion 60. Therefore, the proximity sensor 1A according to the present embodiment is manufactured. The effect that the above various restrictions are reduced can also be obtained.

  In addition, as shown in FIGS. 8A and 9, in the proximity sensor 1 </ b> A according to the present embodiment, as described above, the groove portion 43 extending in the circumferential direction is provided on the outer peripheral surface of the protruding portion 42. Yes. By configuring in this way, the so-called anchor effect can be obtained as described above.

  More specifically, as shown in FIG. 9, when the second sealing portion 60 contracts with a change in environmental temperature, the outer periphery of the second sealing portion 60 that is a contact surface with the clamp 50. Shrinkage occurs in the vicinity of the surface in the direction indicated by arrow E in the figure, and along with this, shear stress is generated in the direction of arrow F shown in the figure at the interface between the joining interposed member 40 and the second sealing portion 60. However, since the groove 43 is located on the outer peripheral surface of the protrusion 42, the shear stress can be prevented from reaching the tip 42a of the protrusion 42, and as a result, peeling occurs at the interface. Can be suppressed.

  As described above, by providing the protruding portion 42 having the above-described configuration in the bonding interposed member 40, a high bonding force can be secured at the connection portion of the cable 30 to the case 10, and damage such as peeling at the portion is prevented. Occurrence can be greatly suppressed, and as a result, the proximity sensor can be further improved in environmental resistance.

  In addition, with reference to FIG. 9, it is preferable that thickness t1 in the thinnest part of the protrusion part 42 is 0.3 mm or more and 0.5 mm or less. More specifically, in the circumferential direction of the protrusion 42, it is preferable that the thickness t1 includes a portion having a thickness of 0.3 mm or more and 0.5 mm or less. By comprising in this way, the elasticity and rigidity of the protrusion part 42 are adjusted appropriately, and the followability mentioned above will be obtained more reliably. However, the thickness of the protrusion 42 is not particularly limited to this.

  Moreover, it is preferable that the axial direction length L of the protrusion part 42 shall be 0.5 mm or more. By setting the axial length L to 0.5 mm or more, the elasticity and rigidity of the protrusion 42 are appropriately adjusted, and the above-described followability can be obtained more reliably. However, the axial length of the protrusion 42 is not particularly limited to this.

  Furthermore, the width W of the groove 43 is preferably 0.5 mm or more. By setting the width W to 0.5 mm or more, the elasticity and rigidity of the protrusion 42 are appropriately adjusted, and the above-described followability can be obtained more reliably. However, the width of the groove 43 is not particularly limited to this.

  Further, as described above, in the proximity sensor 1A according to the present embodiment, the case where the groove portion 43 extending in the circumferential direction is provided on the outer peripheral surface of the protruding portion 42 is illustrated, but the uneven portion different from the shape is the protruding portion. It is good also as providing in any one or both of the outer peripheral surface of 42, and an internal peripheral surface, and the protrusion 42 may provide the hole penetrated along the radial direction of the protrusion part 42, various notches, etc. . Even in such a configuration, the so-called anchor effect described above can be obtained.

  In addition, as described above, in the proximity sensor 1A according to the present embodiment, the case where the protruding portion 42 is substantially cylindrical has been exemplified, but the outer shape of the protruding portion 42 is any shape as long as it is cylindrical. For example, the outer shape may be a polygonal cylinder, or the outer shape may be an elliptic cylinder.

  Further, as described above, in the proximity sensor 1 </ b> A according to the present embodiment, the base member 41 of the joining interposition member 40 is welded to the sheath 33 of the cable 30, so that the joint interposition member 40 is joined to the cable 30. . Here, the welding can be easily performed when the difference in melting point between members to be joined is generally in the range of about 50 ° C. or less. Therefore, when the joining interposition member 40 and the sheath 33 of the cable 30 are made of the same resin as in the present embodiment, the welding can be easily performed. When the sheath 33 of the cable 30 is made of a different resin, it is necessary to select the resin in consideration of the above-described difference in melting point.

  In addition, with reference to FIG. 8, thickness t2 of the welding part 41a of the joining interposition member 40 formed by welding the joining interposition member 40 to the sheath 33 is set in consideration of the sealing property in the said part. There is a need. Therefore, it is preferable that the thickness before welding of the part used as the welding part 41a of the base 41 is about 0.3 mm or more and 0.5 mm or less.

  Further, as described above, in the present embodiment, the case where the base portion 41 of the joining interposed member 40 is fixed to the end portion of the sheath 33 located on the one end side of the cable 30 has been described as an example. However, this configuration is not necessarily required, and the sheath 33 may be fixed to the sheath 33 at a position away from the end portion. That is, the joining interposition member only needs to have a cylindrical base portion that covers the outer peripheral surface of the sheath and a cylindrical protrusion portion that protrudes toward the one end side of the cable, and the end portion and the base portion of the sheath. And the positional relationship between the end portion of the sheath and the protruding portion can be variously changed.

(First modification)
FIG. 10 is an enlarged cross-sectional view of a main part of a proximity sensor according to a first modification based on the present embodiment. Hereinafter, the proximity sensor 1B according to the first modification will be described with reference to FIG.

  As shown in FIG. 10, the proximity sensor 1B according to the first modified example has the joint member 40 that does not have the protruding portion 42 when compared to the proximity sensor 1A in the first embodiment described above. Instead, a cover 44 is provided so as to cover the end surfaces of the sheath 33 and the shield material 32. Here, the bending elastic modulus of the joint member 40 and the hanging flatness of the cable 30 are both the same as those of the first embodiment described above.

  The proximity sensor 1B configured as described above reduces the residual stress generated when the second sealing portion 60 is cured and changes in the environmental temperature as compared with the proximity sensor 1A in the first embodiment described above. As in the case of the first embodiment described above, the second sealing portion 60 is inferior in terms of the followability of the joining interposing member 40 during expansion and contraction of the second sealing portion 60 accompanying the above. In addition, while ensuring the durability of the cable 30 and the joining interposition member 40, a high joining force can be secured at the connection portion of the cable 30 to the case 10, and the occurrence of breakage such as peeling at the portion can be greatly suppressed, and as a result As a result, the environment resistance is particularly excellent.

(Second modification)
FIG. 11 is an enlarged cross-sectional view of a main part of a proximity sensor according to a second modification based on the present embodiment. Hereinafter, with reference to this FIG. 11, the proximity sensor 1C which concerns on a 2nd modification is demonstrated.

  As shown in FIG. 11, when the proximity sensor 1C according to the second modification is compared with the proximity sensor 1A according to the first embodiment described above, the joining interposed member 40 is added to the base 41 and the protruding portion 42. The only difference is that it further includes a lid portion 44 that covers the end surfaces of the sheath 33 and the shield material 32. Here, the bending elastic modulus of the joint member 40 and the hanging flatness of the cable 30 are both the same as those of the first embodiment described above.

  The proximity sensor 1 </ b> C configured in this way is similar to the above-described first embodiment, in that the residual stress generated when the second sealing portion 60 is cured is reduced, and the second accompanying the change in the environmental temperature. The case is excellent in the followability of the projecting portion 42 when the sealing portion 60 expands and contracts, and the durability of the second sealing portion 60, the cable 30, and the joining interposition member 40 is ensured. A high bonding force can be secured at the connection portion of the cable 30 with respect to 10, the occurrence of breakage such as peeling at the portion can be greatly suppressed, and as a result, the environment resistance is particularly excellent.

(Third Modification)
FIG. 12 is an enlarged cross-sectional view of a main part of a proximity sensor according to a third modification based on the present embodiment. Hereinafter, the proximity sensor 1D according to the third modification will be described with reference to FIG.

  As shown in FIG. 12, the proximity sensor 1 </ b> D according to the third modified example is provided with the groove portion 43 in the protruding portion 42 of the joint member 40 when compared with the proximity sensor 1 </ b> A in the first embodiment described above. It differs only in that there is no point. Here, the bending elastic modulus of the joint member 40 and the hanging flatness of the cable 30 are both the same as those of the first embodiment described above.

  The proximity sensor 1D configured as described above is similar to the above-described first embodiment, in that the residual stress generated when the second sealing portion 60 is cured is reduced, and the second accompanying the change in the environmental temperature. The case is excellent in the followability of the projecting portion 42 when the sealing portion 60 expands and contracts, and the durability of the second sealing portion 60, the cable 30, and the joining interposition member 40 is ensured. A high bonding force can be secured at the connection portion of the cable 30 with respect to 10, the occurrence of breakage such as peeling at the portion can be greatly suppressed, and as a result, the environment resistance is particularly excellent.

(Fourth modification)
FIG. 13 is an enlarged cross-sectional view of a main part of a proximity sensor according to a fourth modification based on the present embodiment. Hereinafter, with reference to this FIG. 13, the proximity sensor 1E which concerns on a 4th modification is demonstrated.

  As shown in FIG. 13, the proximity sensor 1 </ b> E according to the fourth modified example has the base portion 41 of the joining interposed member 40 that is the sheath 33 of the cable 30 when compared with the proximity sensor 1 </ b> D according to the third modified example. The only difference is that the protruding portion 42 is provided so as to extend continuously from the base 41 of the portion corresponding to the portion where the end face of the sheath 33 is located. Yes. Here, the bending elastic modulus of the joint member 40 and the hanging flatness of the cable 30 are both the same as those of the first embodiment described above.

  In the proximity sensor 1E configured in this way, as in the case of the above-described first embodiment, the residual stress generated when the second sealing portion 60 is cured is reduced, and the second sensor 1E that accompanies a change in environmental temperature is used. The case is excellent in the followability of the projecting portion 42 when the sealing portion 60 expands and contracts, and the durability of the second sealing portion 60, the cable 30, and the joining interposition member 40 is ensured. A high bonding force can be secured at the connection portion of the cable 30 with respect to 10, the occurrence of breakage such as peeling at the portion can be greatly suppressed, and as a result, the environment resistance is particularly excellent.

(5th modification)
FIG. 14 is an enlarged cross-sectional view of a main part of a proximity sensor according to a fifth modification based on the present embodiment. Hereinafter, with reference to this FIG. 14, the proximity sensor 1F which concerns on a 5th modification is demonstrated.

  As shown in FIG. 14, when the proximity sensor 1F according to the fifth modified example is compared with the proximity sensor 1E according to the fourth modified example described above, the base 41 and the protrusion 42 of the joining interposed member 40 are It differs in that it has substantially the same size of outer shape, and accordingly, the inner diameter of the clamp 50 corresponding to the protrusion 42 is larger than the inner diameter of the clamp 50 corresponding to the base 41. It is different in the point that is done. Here, the bending elastic modulus of the joint member 40 and the hanging flatness of the cable 30 are both the same as those of the first embodiment described above.

  The proximity sensor 1 </ b> F configured as described above is similar to the above-described first embodiment in that the residual stress generated when the second sealing portion 60 is cured is reduced, and the second accompanying the change in the environmental temperature. The case is excellent in the followability of the projecting portion 42 when the sealing portion 60 expands and contracts, and the durability of the second sealing portion 60, the cable 30, and the joining interposition member 40 is ensured. A high bonding force can be secured at the connection portion of the cable 30 with respect to 10, the occurrence of breakage such as peeling at the portion can be greatly suppressed, and as a result, the environment resistance is particularly excellent.

(Embodiment 2)
FIGS. 15 and 16 are a flow diagram and an assembly diagram for explaining the manufacturing method of the proximity sensor in the second embodiment of the present invention, respectively. Hereinafter, with reference to FIG. 15 and FIG. 16, the manufacturing method of the proximity sensor in this Embodiment is demonstrated.

  As will be described later, the manufacturing method of the proximity sensor according to the present embodiment is slightly different from the manufacturing method of the proximity sensor 1A according to the first embodiment described above. Although it is different, its specific form is almost clear in the assembly drawing of FIG. 16, and therefore illustration thereof is omitted here.

  First, as shown in FIG. 15, the joining intervention member 40 is manufactured (step ST <b> 21), then the joining intervention member 40 is attached to the cable 30 (step ST <b> 22), and then the joining intervention member 40 is attached to the cable 30. Next, the cable 30 is connected to the detection unit assembly 20 (step ST24), and then the detection unit assembly 20 is assembled to the case 10 (step ST25). Since details of these steps ST21 to ST25 are the same as those of steps ST11 to ST15 shown in FIG. 6 described above, description thereof will not be repeated here.

  Next, as shown in FIGS. 15 and 16A, the clamp 50 is assembled to the case 10 (step ST26). More specifically, the fixing portion 51 of the clamp 50 is press-fitted into the opening on the rear end side of the case 10.

  Next, as shown in FIGS. 15 and 16B, the joining interposed member 40 is assembled to the clamp 50 (step ST27). More specifically, the clamp 50 is assembled to the joining intermediate member 40 by press-fitting the base portion 41 of the joining intervention member 40 into the rear end portion of the clamp 50.

  Next, as shown in FIG. 15, a liquid resin is injected into the case 10 and the clamp 50, and is cured (step ST28). The details of step ST28 are the same as step ST17 shown in FIG. 6 described above, and therefore the description thereof will not be repeated here. As described above, the proximity sensor according to the present embodiment having a configuration similar to that of the proximity sensor 1A according to the first embodiment is obtained.

  In the above, the case where the joining interposition member 40 is welded to the cable 30 after the joining interposition member 40 is attached to the cable 30 and before the cable 30 is connected to the detection unit assembly 20. Although illustrated, the joining interposed member 40 may be welded to the cable 30 at any timing after the cable 30 is connected to the detection unit assembly 20 until the proximity sensor is completed. That is, the process ST23 may be performed after any of the processes ST24 to ST28 as long as it is a process after the process ST24.

  Furthermore, in the above, the case where the detection unit assembly 20 is assembled to the case 10 after the cable 30 is connected to the detection unit assembly 20 and before the clamp 50 is assembled to the case 10. Although illustrated, the detection unit assembly 20 may be assembled to the case 10 before the cable 30 is connected to the detection unit assembly 20. That is, step ST25 may be performed before step ST24.

  Also in the case of the proximity sensor in the present embodiment described above, as in the case of the first embodiment described above, the reduction of residual stress generated when the second sealing portion 60 is cured, and the environmental temperature As a result, the second sealing portion 60, the cable 30, and the joining interposed member 40 are durable. As a result, a high bonding force can be secured at the connection portion of the cable 30 to the case 10, and the occurrence of breakage such as peeling at the portion can be greatly suppressed, resulting in particularly excellent environmental resistance. .

(Verification test)
FIG. 17 is a table showing test conditions and test results of the verification test. In this verification test, a number of proximity sensors with various changes in the bending elastic modulus of the joining intervening member and the cable hanging flatness were actually produced, and the degree of environmental resistance was confirmed. It is. Here, the bending elastic modulus of the joining member is changed by changing the type of resin of the joining member to be used, and the hanging flatness of the cable is the diameter of the cable to be used and the sheath of the cable to be used. Changed by changing the type of resin. Note that the structure of the plurality of proximity sensors actually prototyped is the same as that of the proximity sensor 1B (see FIG. 10) according to the first modification described above.

  As shown in FIG. 17, in the verification test, seven types of proximity sensors of Verification Examples 1 to 7 were prepared. In the proximity sensors according to these verification examples 1 to 7, the internal space defined by the case and the clamp is filled with the epoxy resin as the sealing portion, and the bending elastic modulus of the epoxy resin is approximately 8000 MPa.

  In the proximity sensor according to Verification Example 1, the joining member is made of a fluororesin, and the flexural modulus of the fluororesin is 540 to 640 MPa. In addition, the proximity sensor according to Verification Example 1 has a cable sheath made of a fluorine-based resin, and a hanging flatness ratio is 0.45. The fluororesin used for the joining member and the fluororesin used for the cable sheath have different compositions.

  In the proximity sensor according to Verification Example 2, the joining member is made of a fluororesin, and the flexural modulus of the fluororesin is 540 to 640 MPa. In addition, the proximity sensor according to Verification Example 2 has a cable sheath made of a fluorine-based resin, and a hanging flatness ratio is 0.15. The fluororesin used for the joining member and the fluororesin used for the cable sheath have different compositions.

  In the proximity sensor according to Verification Example 3, the joining member is made of a fluororesin, and the flexural modulus of the fluororesin is 210 MPa. In addition, the proximity sensor according to Verification Example 3 has a cable sheath made of a fluorine-based resin, and a hanging flatness ratio is 0.15. The fluororesin used for the joining member and the fluororesin used for the cable sheath have different compositions.

  In the proximity sensor according to Verification Example 4, the joining member is made of a fluororesin, and the flexural modulus of the fluororesin is 210 MPa. In the proximity sensor according to Verification Example 4, the cable sheath is made of a fluorine-based resin, and the hanging flatness is 0.52. The fluororesin used for the joining member and the fluororesin used for the cable sheath have the same composition.

  In the proximity sensor according to Verification Example 5, the joining interposed member is made of a fluororesin, and the flexural modulus of the fluororesin is 210 MPa. In the proximity sensor according to Verification Example 5, the sheath of the cable is made of a fluorine-based resin, and the hanging flatness is 0.44. The fluororesin used for the joining member and the fluororesin used for the cable sheath have different compositions.

  In the proximity sensor according to Verification Example 6, the joining member is made of a fluororesin, and the flexural modulus of the fluororesin is 210 MPa. In addition, the proximity sensor according to Verification Example 6 has a cable sheath made of a fluorine-based resin, and a hanging flatness ratio is 0.30. The fluororesin used for the joining member and the fluororesin used for the cable sheath have the same composition.

  In the proximity sensor according to Verification Example 7, the joining member is made of a fluororesin, and the flexural modulus of the fluororesin is 80 MPa. In addition, the proximity sensor according to Verification Example 7 has a cable sheath made of a fluorine-based resin, and the hanging flatness ratio is 0.71. The fluororesin used for the joining member and the fluororesin used for the cable sheath have different compositions.

  In the verification test, the seven types of proximity sensors in Verification Examples 1 to 7 were immersed in water-soluble cutting oil (JIS A1 type coolant and JIS A3 type coolant) heated to a predetermined temperature for a predetermined time, and thereafter By measuring the insulation resistance value of the joint, confirm the durability (oil resistance) of the joint member and cable, and then bend the root of the part pulled out from the cable clamp multiple times to approximately 90 °. Then, it was confirmed whether or not the joining force between the respective members was sufficient by checking whether or not peeling occurred on the joining surface by the subsequent inspection.

  In the evaluation, when the joined member and cable are durable and the joining force between the members is sufficient, this is judged as “good”, and the joined member and cable are durable. This was judged as “impossible” when there was no or the bonding force between the members was insufficient.

  As is clear from the test results shown in FIG. 17, the bending elastic modulus of the resin constituting the joining interposed member is 80 MPa or more and 210 MPa or less, and the cable hanging flatness is 0.30 or more and 0.71 or less. In each of the verification examples 4 to 7, it was confirmed that each of the joining interposed member and the cable had durability and the joining force between the members was sufficient. On the other hand, in the verification examples 1 to 3 that do not satisfy the above conditions, it was confirmed that the bonding force between the members was insufficient, while the bonding interposed member and the cable were durable.

  Based on the above test results, the internal space defined by the case and the clamp is filled with the epoxy resin as the sealing portion, and the flexural modulus of the resin constituting the joining interposed member is 80 MPa or more and 210 MPa or less. In addition, when the cable hanging flatness is 0.30 or more and 0.71 or less, peeling occurs at these joint surfaces while ensuring the durability of the sealing portion, the cable, and the joint member. It can be understood that the electronic device is particularly excellent in environmental resistance, which can prevent the occurrence of the phenomenon.

  In the above-described first and second embodiments of the present invention and the modifications thereof, the case where the joining member is fixed to the cable by welding is described as an example, but it is not always necessary to configure as such. For example, it is good also as providing a joining interposition member by insert-molding liquid resin in the edge part of the sheath of a cable.

  In the above-described first and second embodiments of the present invention and modifications thereof, the case where a composite cable provided with a shielding material is used as the cable drawn from the case has been described as an example. Various types of cables can be used. For example, the present invention can be applied to a composite cable not including the above-described shielding material, or a cable (so-called lead wire or the like) including only a conductive wire and a sheath covering the conductive wire. is there.

  Moreover, in Embodiment 1 and 2 of this invention mentioned above and its modification, the internal space prescribed | regulated by a case and a clamp is filled with the 1st sealing part and the 2nd sealing part However, it is not always necessary to configure in this way, and it may be filled only with a single sealing portion.

  Further, in the above-described first and second embodiments of the present invention and the modifications thereof, the case where the joining interposed member is configured by a single component has been described as an example, but this is a plurality of components. It may be configured and may be a two-color molded product.

  In the above-described first and second embodiments of the present invention and modifications thereof, the case where the present invention is applied to a proximity sensor has been described as an example. However, the present invention is not limited to a proximity sensor. Of course, the present invention can also be applied to various other electronic devices.

  As described above, the above-described embodiment and its modifications disclosed herein are illustrative in all respects and are not restrictive. The technical scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  1A to 1F Proximity sensor, 10 case, 20 detector assembly, 21 core, 21a support groove, 22 detector coil, 23 coil case, 24 circuit board, 24a land, 25a to 25c electronic component, 26 first sealing portion, 30 Cable, 31 Core wire, 31a Conductive wire, 32 Shield material, 33 Sheath, 40 Joining interposed member, 41 Base part, 41a Welded part, 42 Protruding part, 42a Tip part, 43 Groove part, 44 Cover part, 50 Clamp, 51 Fixed part 52 holding part 53 connecting part 53a gate 53b light guiding part 60 second sealing part 100 rod 110 weight

Claims (7)

A case provided with an opening,
An electronic component housed in the case;
One end is electrically connected to the electronic component by being inserted through the opening, and the other end is a cable drawn out of the case,
A joining interposition member attached to the cable;
A cylindrical clamp that is fitted into the opening and holds the cable by fitting the joining interposed member;
A sealing portion that fills an internal space defined by the case and the clamp;
The cable has a core wire including a conductive wire, and a sheath covering the core wire,
The core wire is exposed in the portion on the one end side of the cable without being covered by the sheath,
The bonding interposition member is bonded to the sheath and bonded to the sealing portion,
The sealing portion is made of an epoxy resin,
The joining interposed member is made of a resin having a flexural modulus of 80 MPa or more and 210 MPa or less,
The cable has a total length of 500 mm and connects both ends thereof to form a loop. A rod is inserted inside the cable to suspend it, and a load of 1.5 N is applied to the lower end of the cable. When the inner diameter along the vertical direction in the outer shape when applied is a and the inner diameter along the horizontal direction is b, the hanging flatness expressed by (ab) / a is 0. Electronic equipment composed of 30 or more and 0.71 or less.   The electronic device according to claim 1, wherein the joining interposed member and the sheath are made of the same resin.   The electronic device according to claim 1, wherein the joining interposed member is made of a fluorine-based resin.   The electronic device according to claim 1, wherein the sheath is made of a fluorine-based resin.   The electronic device according to claim 1, wherein each of the joining interposed member and the sheath is made of a fluorine-based resin. The joining interposition member has a tubular base part that joins the sheath by covering the outer peripheral surface of the sheath, and a tubular projecting part that projects toward the one end side of the cable,
The inner peripheral surface and the outer peripheral surface of the protruding portion and the end surface on the tip side in the axial direction of the protruding portion are all covered with the sealing portion, whereby the sealing portion is joined to the protruding portion. Item 6. The electronic device according to any one of Items 1 to 5.   The electronic device according to claim 1, wherein the joining interposed member is welded to the sheath.

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