Resin case, sensor module, method for manufacturing the resin case, and method for manufacturing the sensor module

Abstract

To provide a resin case having high waterproofness, a sensor module, a manufacturing method of a resin case, and a manufacturing method of a sensor module.SOLUTION: A resin case 10 includes a resin case body 2 and a lid body 3, and a cut-off member 4 arranged between the case body 2 and the lid body 3. The melting point of the cut-off member 4 is lower than the melting points of the case body 2 and the lid body 3, and the cut-off member 4 is mixed with the case body 2 and the lid body 3. A sensor module 1 includes a resin case 10, a magnetic field sensor 11 stored in the resin case 10, and a cable 13 for collectively storing a plurality of electric wires 131 electrically connected to the magnetic field sensor 11 in a sheath 132, and the sheath 132 and the lid body 3 are mixed with each other. The cut-off member 4 and the case body 2 are mixed with each other by molding heat of the resin in a step of molding the case body 2, and the cut-off member 4, the sheath 132 and the lid body 3 are mixed with each other by molding heat of the resin in a step of molding the lid body 3.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a resin case, a sensor module, a method for manufacturing a resin case, and a method for manufacturing a sensor module. [Background Art]

[0002] Conventionally, sensors that detect physical quantities such as temperature and magnetism are often used by being housed in a case having a waterproof function. For example, in the torque sensor described in Patent Document 1, the waterproof performance of the cover is ensured by an endless sealing member. In the sensor module described in Patent Document 2, waterproof performance is ensured by sandwiching a plurality of waterproof sheets between a cover and a case that houses a sensor mounted on a circuit board. In the sensor case described in Patent Document 3, waterproof performance is ensured by fitting the first case and the spigot portion of the second case. [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Unexamined Patent Application Publication No. 11-248564 [Patent Document 2] Japanese Unexamined Patent Application Publication No. 2017-58279 [Patent Document 3] Japanese Unexamined Patent Application Publication No. 2021-135180 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] For example, cases for sensors mounted on vehicles are sometimes required to be small and lightweight, and to have high waterproof performance capable of preventing the intrusion of moisture caused by capillary action through even slight gaps between members. An object of the present invention is to provide a resin case, a sensor module, a method for manufacturing a resin case, and a method for manufacturing a sensor module that have high waterproof performance. [Means for Solving the Problem]

[0005] The present invention aims to solve the above problems by providing a first case member made of resin. resin Second case component , and a third case member made of resin The case comprises a water-sealing member disposed between the first case member and the second case member, wherein the melting point of the water-sealing member is lower than the melting points of the first case member and the second case member, and the water-sealing member melts together with the first case member and the second case member. Ori , The third case member has a higher melting point than the water-sealing member, the water-sealing member is formed in an annular shape, the third case member is positioned on the inner circumference side of the water-sealing member, the third case member is in contact with the inner circumferential surface of the water-sealing member, the first case member and the second case member are arranged along a predetermined alignment direction with the water-sealing member in between, the third case member has a flange portion that is sandwiched between the first case member and the second case member together with the water-sealing member along the predetermined alignment direction, and the flange portion of the third case member is in contact with the inner circumferential surface of the water-sealing member. A resin case is provided.

[0006] Furthermore, the present invention aims to solve the above problems by providing a sensor module comprising the above-mentioned resin case, a physical quantity sensor housed in the resin case, and a cable in which a plurality of electric wires electrically connected to the physical quantity sensor are collectively housed in a sheath, wherein the cable is led out from the second case member, and the sheath and the second case member are fused together.

[0007] Furthermore, the present invention aims to solve the above problems and provides a method for manufacturing a resin case, comprising the steps of molding the water-sealing member, molding the first case member, and molding the second case member, wherein the water-sealing member and the first case member melt together due to the molding heat of the resin in the molding step of the first case member, and the water-sealing member and the second case member melt together due to the molding heat of the resin in the molding step of the second case member.

[0008] Furthermore, the present invention aims to solve the above problems and provides a method for manufacturing the above-described sensor module, comprising the steps of molding the water-sealing member, molding the first case member, and molding the second case member, wherein the water-sealing member and the first case member melt together due to the molding heat of the resin in the step of molding the first case member, and the water-sealing member, the sheath, and the second case member melt together due to the molding heat of the resin in the step of molding the second case member. [Effects of the Invention]

[0009] According to the present invention, the resin case, sensor module, method for manufacturing the resin case, and method for manufacturing the sensor module can ensure high water resistance. [Brief explanation of the drawing]

[0010] [Figure 1] (a) is a perspective view showing a sensor module according to an embodiment of the present invention. (b) is a perspective view of the sensor module from a different angle than (a). [Figure 2] Figure 1(a) is an exploded perspective view showing each component of the sensor module as seen from the angle indicated. [Figure 3] Figure 1(b) is an exploded perspective view showing each component of the sensor module as seen from the angle indicated. [Figure 4] This is a cross-sectional view showing the sensor module. [Figure 5] This is a magnified view of a portion of Figure 4. [Figure 6] (a) is a perspective view showing the holder. (b) is a perspective view showing the support member. (c) is a perspective view showing the clamping member. [Figure 7] This is an explanatory diagram showing the process of forming the lid. [Modes for carrying out the invention]

[0011] [Embodiment] Embodiments of the present invention will be described with reference to the drawings. In this embodiment, the present invention will be described in the case where it is applied to a sensor module for detecting the steering torque of a vehicle, but the application of the present invention is not limited to this, and it can be applied to sensor modules for detecting various physical quantities, or to resin cases of electrical products, etc.

[0012] Fig. 1(a) is a perspective view showing a sensor module 1 according to an embodiment of the present invention. Fig. 1(b) is a perspective view of the sensor module 1 seen from a different angle from that in Fig. 1(a). Fig. 2 is an exploded perspective view showing each constituent member of the sensor module 1 seen from the angle shown in Fig. 1(a). Fig. 3 is an exploded perspective view showing each constituent member of the sensor module 1 seen from the angle shown in Fig. 1(b). Fig. 4 is a cross-sectional view showing the sensor module 1. Fig. 5 is a partially enlarged view of Fig. 4.

[0013] The sensor module 1 is attached to a housing of a vehicle steering device, and detects steering torque transmitted by a steering shaft connected to a steering wheel.

[0014] The sensor module 1 comprises: a resin case 10; a pair of magnetic field sensors 11; a printed circuit board 12 on which the magnetic field sensors 11 are mounted; a cable 13 formed by collectively accommodating a plurality of electric wires 131 electrically connected to the pair of magnetic field sensors 11 in a sheath 132; a first magnetic flux collecting ring 14 and a second magnetic flux collecting ring 15 made of a soft magnetic material; and a pair of metal collars 16 into which bolts for attachment to an attachment target are inserted.

[0015] The magnetic field sensor 11 is an embodiment of the physical quantity sensor according to the present invention, and outputs an electric signal corresponding to the intensity of the detected magnetic field. The cable 13 has seven electric wires 131, and these electric wires 131 are electrically connected to each of the pair of magnetic field sensors 11. The electric wire 131 is an insulated electric wire in which a core wire 131a made of a conductor is covered with an insulating coating material 131b. The core wire 131a of each electric wire 131 is soldered to an electrode of the printed circuit board 12, and is electrically connected to a terminal of the magnetic field sensor 11 via a wiring pattern of the printed circuit board 12. The sheath 132 is made of, for example, polyvinyl chloride resin, urethane resin, fluororesin, or fluororubber.

[0016] The first magnetism collecting ring 14 and the second magnetism collecting ring 15 each integrally include annular portions 141, 151 formed in an annular shape, and protruding pieces 142, 152 protruding radially outward from a part of the annular portions 141, 151, respectively. In the present embodiment, the first magnetism collecting ring 14 and the second magnetism collecting ring 15 each have two protruding pieces 142, 152, and a pair of magnetic field sensors 11 are arranged between the two protruding pieces 142 of the first magnetism collecting ring 14 and the two protruding pieces 152 of the second magnetism collecting ring 15.

[0017] Inside the annular portions 141, 151 of the first magnetism collecting ring 14 and the second magnetism collecting ring 15, a torsion bar (torsion shaft), which is a part of a steering shaft, is arranged together with a permanent magnet and a yoke, and the intensity of the magnetic field detected by the pair of magnetic field sensors 11 changes according to the torsion amount of the torsion bar. The electrical signal output by the magnetic field sensors 11 is input to a control device as a signal indicating the steering torque transmitted by the steering shaft, and the control device controls, for example, a power steering device according to this signal.

[0018] The resin case 10 is configured to include a case main body 2 having a hollow body portion 21 that accommodates a printed circuit board 12 on which the magnetic field sensors 11 are mounted, a lid body 3 that covers an opening 210 of the body portion 21 of the case main body 2, a water-stop member 4 arranged between the case main body 2 and the lid body 3, and a holder 5 that holds the printed circuit board 12 and ends of a cable 13 inside the body portion 21 of the case main body 2. In the present embodiment, the holder 5 is configured by a combination of a support member 6 that supports the printed circuit board 12 and the cable 13, and a clamping member 7 that clamps a part of the cable 13 between the clamping member 7 and the support member 6.

[0019] The case main body 2 is an embodiment of the first case member of the present invention. The lid body 3 is an embodiment of the second case member of the present invention. The holder 5 is an embodiment of the third case member of the present invention.

[0020] The case body 2, lid 3, and the support members 6 and clamping members 7 of the holder 5 are made of resin. The water-sealing member 4 is made of a material that is softer and has a lower modulus of elasticity than the case body 2, lid 3, and the support members 6 and clamping members 7 of the holder 5. Furthermore, the melting point of the water-sealing member 4 is lower than the melting points of the case body 2, lid 3, and the support members 6 and clamping members 7 of the holder 5.

[0021] The case body 2 integrally comprises a body portion 21, an annular portion 22 that holds the annular portions 141 and 151 of the first magnetic collecting ring 14 and the second magnetic collecting ring 15, and a mounting portion 23 provided between the body portion 21 and the annular portion 22. Hereinafter, the direction in which the body portion 21, the annular portion 22, and the mounting portion 23 are aligned will be referred to as the axial direction. The body portion 21 has a rectangular shape when viewed from the axial direction, and an opening 210 is formed at the axial end opposite to the mounting portion 23 side. The cable 13 is led out from the cover 3 along the axial direction.

[0022] The mounting portion 23 is rectangular in shape, with its longitudinal direction parallel to the long side of the rectangular shape of the body portion 21, and each end of the mounting portion holds a collar 16. The mounting portion 23 is fixed to the mounting object by bolts inserted through the collar 16, closing the opening formed in the mounting object. In this embodiment, the mounting object is the housing of the steering device. The annular portion 22 of the case body 2 is positioned on the inside of the housing. The body portion 21 is positioned on the outside of the housing, where it is hit by water droplets splashed up by the tires when the vehicle is running.

[0023] The water-stopping member 4 is formed in an annular shape with rounded corners when viewed from the axial direction. Furthermore, the water-stopping member 4 has a rectangular cross-sectional shape in the axial direction, as shown in Figure 5, with one side surface 4c between the inner circumferential surface 4a and the outer circumferential surface 4b facing one axial side (towards the case body 2) and the other side surface 4d facing the other axial side (towards the lid 3).

[0024] The case body 2's body portion 21 is covered by the lid 3 at one axial end, and a notch 211 is formed in an annular shape at the outer corner of this end to accommodate a portion of the water-sealing member 4 in the axial direction. The water-sealing member 4 has a portion of its axial direction, including one side surface 4c, housed in the notch 211 of the body portion 21, while the other portion of its axial direction, including the other side surface 4d, protrudes axially from the notch 211 of the body portion 21. The holder 5 is positioned on the inner circumference side of the water-sealing member 4 and is in contact with the inner circumferential surface 4a of the water-sealing member 4.

[0025] The case body 2 and the lid 3 are aligned along a predetermined alignment direction with the water-sealing member 4 in between. In this embodiment, this predetermined alignment direction is the axial direction as described above. Furthermore, the water-sealing member 4 is fused with the case body 2 and the lid 3. This prevents moisture from entering the holder 5 side through the small gap between the case body 2 and the lid 3, thereby enhancing the waterproofness of the sensor module 1.

[0026] Figure 6(a) is a perspective view showing the holder 5, which is a combination of the support member 6 and the clamping member 7. Figure 6(b) is a perspective view showing the clamping member 7. Figure 6(c) is a perspective view showing the support member 6.

[0027] The support member 6 integrally comprises a semi-cylindrical sheath support portion 61 that supports a part of the sheath 132, a wire support portion 62 that supports a plurality of electric wires 131 led out from the sheath 132, a board support portion 63 that supports the printed circuit board 12, and a wall portion 64 provided so as to protrude from the end of the sheath support portion 61 on the side of the wire support portion 62 in a direction perpendicular to the axial direction.

[0028] The sheath support portion 61 of the support member 6 has a semicircular shape when viewed from the axial direction and extends in the axial direction. The wire support portion 62 has a plurality of holding grooves 621 for each of the plurality of wires 131, and a plurality of wire insertion holes 622 through which each of the plurality of wires 131 is inserted. The wire insertion holes 622 are in communication with the ends of the holding grooves 621, and the core wires 131a of the wires 131 protruding from the wire insertion holes 622 are soldered to the electrodes of the printed circuit board 12.

[0029] The substrate support portion 63 has a plate portion 631 facing the mounting surface 12a of the printed circuit board 12 on which the magnetic field sensor 11 is mounted, and a pair of projections 632 erected on the plate portion 631. The pair of projections 632 are inserted through a pair of through holes 121 formed in the printed circuit board 12 to position the printed circuit board 12.

[0030] The wall portion 64 is larger than the wire support portion 62 and protrudes perpendicular to the axial direction. The wall portion 64 has a thick portion 641 and a thin portion 642 with different thicknesses in the axial direction, and the thin portion 642 is formed to surround the outer edge of the thick portion 641. On the surface of the wall portion 64 facing the wire support portion 62, a stepped surface 64a is formed due to the difference in thickness between the thick portion 641 and the thin portion 642.

[0031] The clamping member 7 integrally comprises a semi-cylindrical sheath support portion 71 that supports a part of the sheath 132, a wire support portion 72 that supports a plurality of electric wires 131 led out from the sheath 132, and a wall portion 73 that is provided so as to protrude from the end of the sheath support portion 71 on the wire support portion 72 side in a direction perpendicular to the axial direction.

[0032] The sheath support portion 71 of the clamping member 7 has a semicircular shape when viewed from the axial direction and extends in the axial direction. The sheath 132 is completely enclosed in the circumferential direction by the sheath support portion 61 of the support member 6 and the sheath support portion 71 of the clamping member 7. The wire support portion 72 faces the wire support portion 62 of the support member 6, sandwiching the multiple wires 131. The wire support portion 72 has multiple notches 721 through which the multiple wires 131 are each inserted.

[0033] The wall portion 73 of the clamping member 7 protrudes more than the wire support portion 72 and in a direction perpendicular to the axial direction. Similar to the wall portion 64 of the support member 6, the wall portion 73 has a thick portion 731 and a thin portion 732 with different thicknesses in the axial direction, and the thin portion 732 is formed to surround the outer edge of the thick portion 731. On the surface of the wall portion 73 facing the wire support portion 72, a stepped surface 73a is formed due to the difference in thickness between the thick portion 731 and the thin portion 732.

[0034] The holder 5 has a flange portion 51 that abuts against the axially open end surface 21a of the body portion 21 of the case body 2. The flange portion 51 is annular in shape, formed by a combination of a thin-walled portion 642 in the wall portion 64 of the support member 6 and a thin-walled portion 732 in the wall portion 73 of the clamping member 7. The flange portion 51 has an opposing surface 51a that faces the axially open end surface 21a of the body portion 21, and the holder 5 is positioned axially relative to the case body 2 by this opposing surface 51a abutting against the open end surface 21a of the body portion 21. In addition, the holder 5 is positioned perpendicular to the axial direction relative to the case body 2 by the stepped surface 64a of the support member 6 and the stepped surface 73a of the clamping member 7 fitting into the inner surface 21b of the body portion 21.

[0035] The holder 5 has a flange portion 51 whose outer circumferential surface 51b is in contact with the inner circumferential surface 4a of the water-sealing member 4. The flange portion 51 is sandwiched between the case body 2 and the lid 3 along the axial direction together with the water-sealing member 4. It is desirable that the outer circumferential surface 51b of the flange portion 51 is in contact with the inner circumferential surface 4a of the water-sealing member 4 over its entire circumference, but it is not necessary that it be in contact with the inner circumferential surface 4a of the water-sealing member 4 in a part of the circumferential direction.

[0036] The case body 2 and the lid 3 are prevented from moving apart in the axial direction by an engaging portion on one of them engaging with an engaged portion on the other. In this embodiment, an engaged portion 24 is integrally provided on the outer circumference of the body portion 21 of the case body 2, and an engaging portion 31 that engages with this engaged portion 24 is provided on the lid 3. The engaged portion 24 is formed around the entire circumference of the body portion 21 and is aligned with the water-stopping member 4 in the axial direction.

[0037] The cover 3 integrally includes the engagement portion 31, a cylindrical tubular portion 32 that covers the sheath 132 of the cable 13, a side plate portion 33 that sandwiches the water-stopping member 4 and the flange portion 51 of the holder 5 between itself and the case body 2 along the axial direction, and an outer circumferential tubular portion 34 that covers one axial end of the body portion 21 of the case body 2 and the outer circumference of the engaged portion 24.

[0038] The sheath 132 of the cable 13 is fused with the cylindrical portion 32 of the cover 3, preventing moisture from entering through the gap between the sheath 132 and the cylindrical portion 32. The cylindrical portion 32 covers the entire circumference of the sheath 132. The engaging portion 31 is formed in an annular shape, projecting inward from the inner circumferential surface 34a of the outer cylindrical portion 34. The outer circumferential surface 24a of the engaged portion 24 is in contact with the inner circumferential surface 34a of the outer cylindrical portion 34. The axial end face 24b of the engaged portion 24 of the case body 2 on the mounting portion 23 side is in contact with the end face 31a of the engaging portion 31 on the side plate portion 33 side.

[0039] Next, the manufacturing method for the sensor module 1 and the resin case 10 will be described. The manufacturing method for the sensor module 1 and the resin case 10 includes the steps of molding the water-stopping member 4, molding the case body 2, molding the support member 6 and clamping member 7 of the holder 5, assembling the components of the sensor module 1 other than the lid 3, and molding the lid 3.

[0040] The melting point of the water-sealing member 4 is, for example, 200°C or less. The melting points of the case body 2, lid 3, support member 6, and clamping member 7 are higher than the melting point of the water-sealing member 4, for example, between 260°C and 300°C. Although different materials may be used for the case body 2, lid 3, support member 6, and clamping member 7, it is desirable to form these members from a common material. This is because forming the case body 2, lid 3, support member 6, and clamping member 7 from a common material prevents the gaps between these members from widening due to differences in thermal expansion coefficients, even if the temperature of the resin case 10 changes.

[0041] When polybutylene terephthalate (PBT) is used as the material for the case body 2, lid 3, support member 6, and clamping member 7, Hytrel®, a copolymer having a polybutylene terephthalate structure and a polytetramethylene glycol structure, manufactured by Toray DuPont, can be suitably used as the material for the water-sealing member 4. Furthermore, when polyamide 612 (PA612) or aromatic polyamide (PPA) is used as the material for the case body 2, lid 3, support member 6, and clamping member 7, a polyamide-based resin can be suitably used as the material for the water-sealing member 4.

[0042] In the process of molding the case body 2, the heat generated during the molding of the resin causes the water-sealing member 4 and the case body 2 to melt together. More specifically, in the notch 211 formed in the body portion 21 of the case body 2, the shaft end face 211a facing the lid 3 side melts together with one side surface 4c of the water-sealing member 4, and the outer peripheral surface 211b of the notch 211 melts together with the inner peripheral surface 4a of the water-sealing member 4. Both the shaft end face 211a and the outer peripheral surface 211b are the inner surfaces of the notch 211.

[0043] In the process of molding the case body 2, a pre-molded water-sealing member 4 is placed in a mold along with a pair of collars 16, and molten resin is injected into the mold to form the case body 2. Since the temperature of this molten resin is higher than the melting point of the water-sealing member 4, the molding heat of the resin used to mold the case body 2 melts a portion of the surface of the water-sealing member 4, causing the water-sealing member 4 and the case body 2 to fuse together and become one unit.

[0044] Here, molding heat refers to the heat applied to the molding resin of the case body 2, and includes not only the heat generated when the molten resin is flowing into the mold for molding the case body 2, but also the heat generated during the annealing process if the case body 2 undergoes an annealing process after solidification.

[0045] Alternatively, the water-sealing member 4 and the case body 2 may be formed by two-color molding. In this case, molten resin that will become the water-sealing member 4 is injected into the mold and solidified, and then molten resin that will become the case body 2 is injected into the mold in which the water-sealing member 4 has been formed. With this molding method as well, the molding heat of the resin used to form the case body 2 melts a portion of the surface of the water-sealing member 4, causing the water-sealing member 4 and the case body 2 to melt together and become one unit.

[0046] In the process of forming the support member 6 and clamping member 7 of the holder 5, the support member 6 and the clamping member 7 are injection molded using separate molds.

[0047] In the assembly process of the components of the sensor module 1 other than the cover 3, the cable 13, with the core wires 131a of each electric wire 131 soldered to the electrodes of the printed circuit board 12 on which the pair of magnetic field sensors 11 are mounted, is placed between the support member 6 and the clamping member 7 of the holder 5. Subsequently, the holder 5, the first magnetic collecting ring 14 and the second magnetic collecting ring 15 are assembled into the case body 2, which has the water-sealing member 4 integrated into it.

[0048] Figure 7 is an explanatory diagram showing the process of molding the lid 3. In this process, the assembly 8, which consists of the magnetic field sensor 11, printed circuit board 12, cable 13, first magnetic collecting ring 14, second magnetic collecting ring 15, collar 16, case body 2, water-sealing member 4, and holder 5, is placed in a mold 9 for molding the lid 3, and molten resin that will become the lid 3 is injected into the cavity 90 of the mold 9 and solidified.

[0049] The mold 9 consists of an upper mold 91 and a lower mold 92. The upper mold 91 has an injection hole 910 for molten resin, and the lower mold 92 has an injection hole 920 for molten resin. These injection holes 910 and 920 are positioned opposite the outer circumferential surface 132a of the sheath 132 of the cable 13. In Figure 7, arrows indicate the direction in which the molten resin injected into the cavity 90 from the injection holes 910 and 920 flows.

[0050] The flange portion 51 of the holder 5 has its outer peripheral surface 51b in contact with the inner peripheral surface 4a of the water-sealing member 4, thereby preventing the water-sealing member 4 from peeling off the case body 2 due to the molten resin. In other words, if there is a gap between the holder 5 and the water-sealing member 4, the pressure of the molten resin flowing into this gap can easily cause the inner peripheral surface 4a of the water-sealing member 4 and the outer peripheral surface 211b of the notch 211 to peel off. However, in this embodiment, the outer peripheral surface 51b of the flange portion 51 is in contact with the inner peripheral surface 4a of the water-sealing member 4, making it difficult for molten resin to enter between the holder 5 and the water-sealing member 4. Furthermore, the flange portion 51 abuts against the open end surface 21a of the body portion 21, preventing the holder 5 from being pushed inward into the body portion 21 due to the pressure of the molten resin.

[0051] In the process of molding the lid 3, the molding heat of the resin in this process causes the water-sealing member 4 and the sheath 132 of the cable 13 to melt together with the lid 3. More specifically, the outer surface 4b of the water-sealing member 4 melts with the outer cylindrical portion 34 of the lid 3, and the side surface 4d of the water-sealing member 4 melts with the side plate portion 33 of the lid 3. The outer surface 132a of the sheath 132 melts with the cylindrical portion 32 of the lid 3. This molding heat refers to the heat applied to the molding resin of the lid 3, and includes not only the heat during the flow of the molten resin injected into the mold for molding the lid 3, but also the heat during the annealing process if the lid 3 undergoes an annealing process after solidification.

[0052] (Operation and Effects of the Embodiment) According to the embodiment described above, the water-sealing member 4 melts into the case body 2 and the lid 3, thereby preventing moisture from entering the holder 5 and improving the waterproofness of the sensor module 1. Furthermore, since the water-sealing member 4 is made of a material with a lower elastic modulus than the case body 2, the lid 3, and the support member 6 and clamping member 7 of the holder 5, even if the water-sealing member 4 and the other members contract or expand at different expansion rates due to a decrease in the temperature of the lid 3 after molding during manufacturing or a change in ambient temperature during use, the elastic deformation of the water-sealing member 4 absorbs this, preventing a gap from forming between the water-sealing member 4 and the other members. Moreover, since the engaging portion 31 of the lid 3 engages with the engaged portion 24 of the case body 2, even if the cable 13 is pulled, the case body 2 and the lid 3 will separate axially, preventing a gap from forming between the water-sealing member 4 and the case body 2 or the lid 3.

[0053] (Summary of the embodiments) Next, the technical concept understood from the embodiments described above will be described using the reference numerals and other symbols from the embodiments. However, the reference numerals in the following description are not limited to the components in the claims that are specifically shown in the embodiments.

[0054] [1] A resin case (10) comprising a first case member (case body 2) and a second case member (lid 3) made of resin, and a water-sealing member (4) disposed between the first case member (2) and the second case member (3), wherein the melting point of the water-sealing member (4) is lower than the melting points of the first case member (2) and the second case member (3), and the water-sealing member (4) is fused with the first case member (2) and the second case member (3).

[0055] [2] The resin case (10) as described in [1] above, wherein the elastic modulus of the material of the water-stopping member (4) is lower than that of the first case member (2) and the second case member (3).

[0056] [3] The resin case (10) according to [2] above, wherein the first case member (2) and the second case member (3) are arranged in a predetermined alignment direction with the water-stopping member (4) in between, an engaging portion (31) is provided on one of the first case member (2) and the second case member (3) and an engaged portion (24) is provided on the other, and relative movement of the first case member (2) and the second case member (3) in the predetermined alignment direction to separate them is suppressed by the engagement of the engaging portion (31) with the engaged portion (24).

[0057] [4] The resin case (10) according to [1] above, further comprising a third case member (holder 5) made of resin with a higher melting point than the water-sealing member (4), wherein the water-sealing member (4) is formed in an annular shape, the third case member (5) is arranged on the inner circumference side of the water-sealing member (4), and the third case member (5) is in contact with the inner circumferential surface (4a) of the water-sealing member (4).

[0058] [5] The resin case (10) according to [4] above, wherein the first case member (2) and the second case member (3) are arranged in a predetermined alignment direction with the water-stopping member (4) in between, and the third case member (5) has a flange portion (51) that is sandwiched between the first case member (2) and the second case member (3) together with the water-stopping member (4) in the predetermined alignment direction, and the flange portion (51) of the third case member (5) is in contact with the inner circumferential surface (4a) of the water-stopping member (4).

[0059] [6] A sensor module (1) comprising a resin case (10) as described in any one of [1] to [5] above, a physical quantity sensor (magnetic field sensor 11) housed in the resin case (10), and a cable (13) in which a plurality of electric wires (131) electrically connected to the physical quantity sensor (11) are collectively housed in a sheath (132), wherein the cable (13) is led out from the second case member (3), and the sheath (132) and the second case member (3) are fused together.

[0060] [7] A method for manufacturing a resin case (10) as described in any one of [1] to [5] above, comprising the steps of: molding the water-stopping member (4); molding the first case member (2); and molding the second case member (3), wherein the water-stopping member (4) and the first case member (2) melt together due to the molding heat of the resin in the step of molding the first case member (2); and the water-stopping member (4) and the second case member (3) melt together due to the molding heat of the resin in the step of molding the second case member (3).

[0061] [8] A method for manufacturing the sensor module (1) described in [6] above, comprising the steps of: molding the water-sealing member (4); molding the first case member (2); and molding the second case member (3), wherein the water-sealing member (4) and the first case member (2) melt together due to the molding heat of the resin in the step of molding the first case member (2); and the water-sealing member (4) and the sheath (132) melt together due to the molding heat of the resin in the step of molding the second case member (3).

[0062] Although embodiments of the present invention have been described above, these embodiments do not limit the invention as defined in the claims. Furthermore, it should be noted that not all combinations of features described in the embodiments are necessarily essential for solving the problem of the invention.

[0063] Furthermore, the present invention can be implemented with appropriate modifications without departing from its spirit. For example, in the above embodiment, the case in which the holder 5 consists of two members, a support member 6 and a clamping member 7, was described, but depending on the configuration of the holder 5, it is also possible to form the holder 5 as a single member. Alternatively, an engaging portion may be provided on the case body 2 and a receiving portion on the lid 3. [Explanation of Symbols]

[0064] 1...Sensor module 10...Plastic case 11…Magnetic field sensor (physical quantity sensor) 13…Cable 131...Electric wire 132...Sheath 2...Case body (first case component) 24...Engaged part 3...Lid (second case component) 31...Engaging part 4...Water-stopping member 4a...Inner circumferential surface 5...Holder (third case component) 51...Flange section

Claims

1. It comprises a first case member made of resin, a second case member made of resin, and a third case member made of resin, and a water-stopping member disposed between the first case member and the second case member, The melting point of the water-stopping member is lower than the melting points of the first case member and the second case member. The water-stopping member is fused with the first case member and the second case member. The third case member has a higher melting point than the water-stopping member. The water-stopping member is formed in an annular shape, and the third case member is arranged on the inner circumference side of the water-stopping member. The third case member is in contact with the inner circumferential surface of the water-stopping member. The first case member and the second case member are arranged along a predetermined alignment direction with the water-stopping member in between. The third case member has a flange portion that is sandwiched between the first case member and the second case member together with the water-stopping member along the predetermined alignment direction, The flange portion of the third case member is in contact with the inner circumferential surface of the water-stopping member. Resin case.

2. The elastic modulus of the material of the water-stopping member is lower than the elastic modulus of the first case member and the second case member. The resin case according to claim 1.

3. The first case member and the second case member are arranged along a predetermined alignment direction with the water-stopping member in between. An engaging portion is provided on one of the first case member and the second case member, and an engaged portion is provided on the other. The relative movement of the first case member and the second case member in the predetermined alignment direction, which causes them to separate, is suppressed by the engagement of the engaging portion with the engaged portion. The resin case according to claim 2.

4. A resin case according to any one of claims 1 to 3, A physical quantity sensor housed in the aforementioned resin case, The cable comprises a plurality of electric wires electrically connected to the physical quantity sensor, all housed together in a sheath. The cable is led out from the second case member, The sheath and the second case member are fused together. Sensor module.

5. A method for manufacturing a resin case according to any one of claims 1 to 3, The process of forming the water-stopping member, The process of forming the first case member, The process includes a step of forming the second case member, The molding heat of the resin during the process of molding the first case member causes the water-stopping member and the first case member to melt together. The water-stopping member and the second case member melt together due to the molding heat of the resin during the molding process of the second case member. A method for manufacturing a resin case.

6. A method for manufacturing a sensor module according to claim 4, The process of forming the water-stopping member, The process of forming the first case member, The process includes a step of forming the second case member, The molding heat of the resin during the process of molding the first case member causes the water-stopping member and the first case member to melt together. The molding heat of the resin during the process of molding the second case member causes the water-stopping member and the sheath to melt together. A method for manufacturing sensor modules.

Images