Sensor device

Abstract

An embodiment may provide a sensor device comprising: a rotor; a stator disposed to correspond to the rotor; a housing disposed outside the rotor and the stator; a main gear coupled to the stator; a sub-gear engaged to the main gear; a magnet disposed at the sub-gear; and a sensor disposed to face the magnet, wherein the sensor device comprises a shield member disposed in the housing and the shield member is disposed to surround the sensor and is in contact with the housing so that a part of the shield member is elastically deformed.

Description

sensor device

[0001] The embodiment relates to a sensor device.

[0002] A sensor device is a device capable of measuring a steering angle or torque. A sensor device for measuring a steering angle may include a main gear connected to an axle and a sub-gear meshed with the main gear. A magnet is arranged on the sub-gear. Furthermore, the sensor device includes a sensor arranged opposite the magnet of the sub-gear.

[0003] The sensor device can measure the steering angle by detecting the rotation of the sub-gear.

[0004] However, when an external magnetic field is introduced in the radial direction, the angle of the magnetic field changes, causing an error between the direction of the actual magnetic field and the direction of the magnetic field detected by the sensor, which causes a problem in that the performance of the sensor device deteriorates.

[0005] Although the shield surrounding the sensor can prevent an external magnetic field from flowing toward the sensor, an external magnetic field can still flow in through the gap in the substrate on which the sensor is mounted in the shield.

[0006] The invention aims to provide a sensor device that prevents the sensor from being influenced by external magnetic fields, and in particular, prevents external magnetic fields from flowing between a shield and a substrate.

[0007] The embodiment may provide a sensor device including a rotor, a stator arranged to correspond to the rotor, a housing arranged on the outside of the rotor and the stator, a main gear coupled to the stator, a sub-gear meshed with the main gear, a magnet arranged on the sub-gear, and a sensor arranged to face the magnet, and including a shield arranged in the housing, wherein the shield is arranged to surround the sensor, and a part of the shield contacts the housing so as to be elastically deformed.

[0008] The above shield can be arranged to overlap the sensor in the radial direction based on the axial direction of the above sub-gear.

[0009] The shield comprises a cylindrical body and a flange extending radially from one end of the body, a portion of the flange being elastically deformable and in contact with the housing.

[0010] The flange includes a flange body and an extension extending outward from the flange body, the flange is spaced apart from the housing, and the extension can be brought into elastically deformable contact with the housing.

[0011] A pair of the above extensions can be arranged opposite each other.

[0012] The above shield can be arranged to overlap the magnet in the radial direction based on the axial direction of the above sub-gear.

[0013] The above body includes a first body and a second body, and the flange can connect the first body and the second body.

[0014] The above flange may be annular.

[0015] The housing may include a first space portion and a second space portion partitioned by a partition wall, and a boss portion arranged along the periphery of a hole connecting the first space portion and the second space portion, the subgear may be rotatably arranged in the hole, and the shield may include a first surface contacting an outer circumferential surface of the boss portion.

[0016] The above extension may be in contact with the bulkhead.

[0017] The housing may include a protrusion protruding from the bulkhead, and the flange may include a hole into which the protrusion is inserted.

[0018] The axial length of the above boss portion may be smaller than the axial length of the above body.

[0019] According to an embodiment, there is an advantage in that an external magnetic field is prevented from flowing toward the sensor through a shield surrounding the sensor.

[0020] In an embodiment, the shield is placed close to the substrate on which the sensor is placed, but since the shield is fixed to the housing, it does not rotate with the gear, thereby preventing the shield and the substrate from colliding and damaging the substrate.

[0021] According to an embodiment, when the shield is inserted into the boss of the housing, the protrusion of the housing is inserted into the hole of the shield, thereby facilitating assembly of the shield and increasing the bonding strength between the housing and the shield.

[0022] According to an embodiment, the contact area of ​​the shield and the housing is formed to be elastically deformable in the axial direction, thereby eliminating the gap between the shield and the substrate on which the sensor is mounted, thereby having the advantage of preventing an external magnetic field from entering between the shield and the substrate.

[0023] Figure 1 is an exploded view showing a sensor device according to an embodiment;

[0024] Fig. 2 is a drawing showing a state in which a sub-gear is mounted in the housing shown in Fig. 1.

[0025] Figure 3 is a perspective view of the shield;

[0026] Figure 4 is a perspective view of a shield according to a modified example, viewed from above.

[0027] Figure 5 is a perspective view of the shield viewed from below.

[0028] Figure 6 is a drawing showing a flange portion mounted on a housing;

[0029] Figure 7 is a drawing showing a state in which a flange portion is mounted on a housing.

[0030] Fig. 8 is a side cross-sectional view of a housing with a sub-gear mounted thereon;

[0031] Figure 9 is a cross-sectional side view showing a state in which the gap between the shield and the substrate is eliminated by the shield contacting the substrate through the restoring force of the extension.

[0032] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0033] However, the technical idea of ​​the present invention is not limited to some of the embodiments described, but can be implemented in various different forms, and within the scope of the technical idea of ​​the present invention, one or more of the components between the embodiments can be selectively combined or substituted for use.

[0034] In addition, terms (including technical and scientific terms) used in the embodiments of the present invention may be interpreted as having a meaning that can be generally understood by a person of ordinary skill in the technical field to which the present invention belongs, unless explicitly and specifically defined and described, and terms that are commonly used, such as terms defined in a dictionary, may be interpreted in consideration of the contextual meaning of the relevant technology.

[0035] Additionally, the terms used in the embodiments of the present invention are intended to describe the embodiments and are not intended to limit the present invention.

[0036] In this specification, the singular may also include the plural unless specifically stated otherwise in the phrase, and when it is described as “A and / or at least one (or more) of B, C”, it may include one or more of all combinations that can be combined with A, B, C.

[0037] Additionally, in describing components of embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used.

[0038] These terms are intended only to distinguish one component from another, and are not intended to limit the nature, order, or sequence of the component.

[0039] And, when a component is described as being 'connected', 'coupled' or 'connected' to another component, it may include not only cases where the component is directly connected, coupled or connected to the other component, but also cases where the component is 'connected', 'coupled' or 'connected' by another component between the component and the other component.

[0040] Additionally, when described as being formed or arranged "above or below" each component, "above" or "below" includes not only cases where the two components are in direct contact with each other, but also cases where one or more other components are formed or arranged between the two components. Furthermore, when expressed as "above" or "below", it can include the meaning of a downward direction as well as an upward direction based on one component.

[0041] Hereinafter, the direction perpendicular to the axial direction of the sensor device or the direction perpendicular to the axial direction of the sub-gear is called the radial direction, and the direction along a circle having a radius in the radial direction with the axis center is called the circumferential direction.

[0042] Fig. 1 is an exploded view showing a sensor device according to an embodiment, and Fig. 2 is a drawing showing a state in which a sub-gear is mounted in the housing shown in Fig. 1.

[0043] Referring to FIGS. 1 and 2, a sensor device according to an embodiment may include a housing (300), a main gear (400), a sub-gear (500), a magnet (600), and a sensor (700). If the sensor device measures torque in addition to a steering angle, it may include a rotor (100) and a stator (200). If the sensor device measures only a steering angle, the steering shaft may be connected to the main gear (400). If the sensor device measures torque in addition, the stator (200) may be connected to an output shaft (not shown), and the rotor (100), at least a portion of which is rotatably disposed on the stator (200), may be connected to an input shaft (not shown).

[0044] Hereinafter, the term “inner” refers to a direction arranged toward the center based on the radial direction, and the term “outer” may refer to a direction opposite to the inner.

[0045] The sensor device according to the embodiment has a feature that, in an environment where an external magnetic field operates, the external magnetic field is prevented from affecting the sensor (700) under the sub-gear (500) through the shield (800).

[0046] The rotor (100) may have a configuration in which a magnet is attached to a cylindrical rotor core connected to a steering input shaft. The stator (200) may include a plurality of teeth, and the teeth may be arranged to face the magnets of the rotor.

[0047] The housing (300) is arranged on the outside of the stator (200) and the rotor (100). The housing (300) may include a main body (300A), an upper cover (300B) arranged on the upper side of the main body (300A), and a lower cover (300C) arranged on the lower side of the main body (300A).

[0048] The main gear (400) is connected to the steering shaft. When the steering shaft rotates, the main gear (400) can rotate. The main gear (400) can be rotatably arranged in the housing (300).

[0049] The sub-gear (500) meshes with the main gear (400). For example, two sub-gear (500) may mesh with the main gear (400). The number of teeth of the sub-gear (500) may be smaller than the number of teeth of the main gear (400). The numbers of teeth of the two sub-gear (500) may be different from each other.

[0050] The subgear (500) may include a gear portion (510) on which teeth are arranged and an axial portion (520) protruding from the gear portion (510).

[0051] The magnet (600) is mounted on the shaft (520) of the sub-gear (500). The magnet (600) may be cylindrical.

[0052] The sensor (700) is mounted on the substrate (SB). The sensor (700) is positioned facing the magnet (600). The sensor (700) can be fixed to the housing (300). The sensor (700) can be a Hall element (Hall IC).

[0053] When the main gear (400) rotates, the sub-gear (500) engaged with the main gear (400) rotates. Then, the magnet (600) mounted on the sub-gear (500) rotates. The sensor (700) detects the change in magnetic field caused by the rotation of the magnet (600).

[0054] The housing (300) may include a first hole (H1) through which the shaft (520) of the sub-gear (500) passes and a boss portion (340) arranged around the first hole (H1). A shield (800) may be mounted on the boss portion (340). The shield (800) blocks an external magnetic field flowing radially toward the sensor (700) with the axis of the sub-gear (500) as the center.

[0055] The specific configuration of the shield (800) that blocks external magnetic fields is as follows.

[0056] Figure 3 is a perspective view of a shield (800).

[0057] Referring to FIG. 3, the shield (800) may be formed of a soft magnetic material. In addition, the shield (800) may include a cylindrical body portion (810) and a flange portion (822) extending radially from one end of the body portion (810). The flange portion (822) may be formed in an annular shape.

[0058] The body part (810) can be arranged to surround the sensor (700). And the body part (810) can also be arranged to surround the magnet (600).

[0059] The flange portion (822) may include an annular flange body (821) and an extension portion (822) extending from the flange body (821). A plurality of extension portions (822) may be arranged. For example, a pair of extension portions (822) may be arranged facing each other.

[0060] The extension (822) extends from the flange body (821) in a cantilever shape and can be elastically deformed by an external force. The extension (820) can have an upwardly bent shape. The shape of the extension (820) is such that when an external force is applied to the extension (820), it can be elastically deformed and provide a restoring force.

[0061] This extension (822) can be in contact with a substrate (SB of FIG. 8) on which a sensor (700) is mounted.

[0062] The shield (800) is described in advance as a single means that is vertically connected to the body (810) and the flange (822), although they can be described separately according to their shape and functional characteristics.

[0063] Fig. 4 is a perspective view of a shield (800) according to a modified example viewed from above, and Fig. 5 is a perspective view of a shield (800) viewed from below.

[0064] The body (810) of the shield (800) according to the modified example may include a first body (810A) and a second body (810B).

[0065] The first body (810A) and the second body (810B) may each be cylindrical members. The first body (810A) and the second body (810B) may be spaced apart from each other. The first body (810A) and the second body (810B) are each positioned to correspond to the position of the boss portion (340) of the housing (300). The inner diameters of the first body (810A) and the second body (810B) may be formed to be equal to or larger than the outer diameter of the boss portion (340).

[0066] The flange portion (822) is formed to extend radially from one end of the first body (810A) and the second body (810B). The flange portion (822) connects the first body (810A) and the second body (810B). The flange portion (822) may include a second hole (H2). The second hole (H2) is formed to penetrate from one surface of the flange portion (822) to the other surface. A plurality of second holes (H2) may be arranged. The second holes (H2) may be arranged between the first body (810A) and the second body (810B).

[0067] An extension (822) may be disposed on one side of a flange body (821) adjacent to the first body (810A). Another extension (822) may be disposed on the other side of the flange body (821) adjacent to the second body (810A). For example, a pair of extensions (822) may be disposed opposite each other.

[0068] Fig. 6 is a drawing showing a flange portion (822) mounted on a housing (300), and Fig. 7 is a drawing showing a state in which the flange portion (822) is mounted on a housing (300).

[0069] Referring to FIGS. 2, 6, and 7, the shaft portion (520) of the subgear (500) passes through the first hole (H1) and is positioned on the inside of the boss portion (340). A magnet (600) is arranged on the shaft portion (520). When the flange portion (822) is mounted, the boss portion (340) is inserted into the inside of the body portion (810).

[0070] In this way, since the cylindrical body part (810) of the shield (800) is inserted into the boss part (340), there is an advantage in that it is easy to assemble the shield (800) into the housing (300).

[0071] The housing (300) may include a protrusion (350). The protrusion (350) may protrude from the bulkhead (310) of the housing (300). There may be a plurality of protrusions (350). The plurality of protrusions (350) may be positioned between two boss portions (340).

[0072] When the shield (800) is inserted into the boss portion (340), the protrusion (350) can be pressed into the second hole (H2) of the flange portion (822). Since the protrusion (350) is pressed into the second hole (H2) while the boss portion (340) is inserted into the body portion (810), there is an advantage of high bonding strength between the shield (800) and the housing (300).

[0073] Fig. 8 is a side cross-sectional view of a housing (300) equipped with a subgear (500).

[0074] Referring to Fig. 8, the housing (300) may include a first space portion (320) and a second space portion (330) partitioned by a partition wall (310). The first space portion (320) and the second space portion (330) are connected through a first hole (H1).

[0075] The axial length (L1) of the boss portion (340) may be smaller than the axial length (L2) of the body portion (810).

[0076] A shield (800) is mounted on the boss portion (340) of the housing (300) and is arranged to overlap the sensor (700) in the radial direction. The shield (800) includes a first surface (S1) that contacts the outer surface of the boss portion (340). In addition, the shield (800) includes a second surface (S2) that contacts the bulkhead (310). The second surface (S2) is arranged perpendicular to the first surface (S1).

[0077] A shield (800) is arranged along the periphery of the sensor (700) to block an external magnetic field flowing radially toward the sensor (700). In addition, the shield (800) is arranged to overlap the magnet (600) in the radial direction. This allows the shield to block an external magnetic field flowing radially toward the magnet (600) as well as the sensor (700).

[0078] External magnetic field (1.25 mT) Comparison example Example Angle change 1.59deg 0.032deg

[0079] As shown in Table 1, when the external magnetic field is 1.25 mT, in the case of the sensor device according to the comparative example without the shield applied, the angle change due to the external magnetic field is large at 1.59 deg, but in the case of the sensor device according to the embodiment, it can be confirmed that the angle change due to the external magnetic field is greatly reduced to 0.032 deg.

[0080] Due to tolerance, a gap may be generated between the end of the body portion (810) and the substrate (SB) in the axial direction of the shield (800), and an external magnetic field may be introduced between the shield (800) and the substrate (SB). However, the gap generated between the shield (800) and the substrate (SB) can be fundamentally blocked through the extension portion (822).

[0081] FIG. 9 is a cross-sectional view showing a state in which the gap occurring between the shield (800) and the substrate (SB) is removed by the restoring force of the extension (822) causing the shield (800) to contact the substrate (SB).

[0082] Referring to FIGS. 8 and 9, the body (810) of the shield (800) is mounted on the boss portion (340) and the extension portion (822) contacts the partition wall (310) of the housing (300). The extension portion (822) contacting the partition wall (310) is elastically deformed and pushes the body (810) toward the substrate (SB) through an appropriate restoring force. In this way, since the body (810) is pushed toward the substrate (SB) through the restoring force of the extension portion (822), the lower end (811) of the body (810) can contact the upper surface (SBa) of the substrate (SB) to block the gap between the shield (800) and the substrate (SB).

[0083] In particular, even if the shield (800) is subjected to external vibration and moves along the axial direction, the extension (822) can be elastically deformed to prevent a gap from occurring between the lower end (811) of the body (810) and the upper surface (SBa) of the substrate (SB).

[0084] Meanwhile, since the lower end (811) of the body (810) presses the substrate (SB) through the restoring force of the extension (822), damage to the substrate (SB) can be minimized.

[0085] The above-described embodiments can be used in various devices such as vehicles or home appliances.

Claims

1. Rotor; A stator arranged to correspond to the rotor; A housing disposed outside the rotor and the stator; A main gear coupled to the above stator; A sub-gear meshed with the above main gear; A magnet placed on the above sub-gear; and Including a sensor positioned opposite to the above magnet, including a shield disposed in the housing; A sensor device in which the shield is arranged to surround the sensor and a portion of the shield is in contact with the housing so as to be elastically deformed.

2. In paragraph 1, The above shield is a sensor device arranged to overlap the sensor in the radial direction based on the axial direction of the above sub-gear.

3. In paragraph 2. The above shield comprises a cylindrical body and a flange extending radially from one end of the body, A sensor device in which a portion of the flange is in elastically deformable contact with the housing.

4. In paragraph 3, The above flange includes a flange body and an extension extending outward from the flange body, A sensor device in which the flange is spaced apart from the housing and the extension is in elastically deformable contact with the housing.

5. In paragraph 4, A sensor device in which a pair of the above extensions are arranged opposite each other.

6. In paragraph 3, The above shield is a sensor device arranged to overlap the magnet in the radial direction based on the axial direction of the above sub-gear.

7. In paragraph 1, The body includes a first body and a second body, and the flange is a sensor device connecting the first body and the second body.

8. In paragraph 1, The above flange is an annular sensor device.

9. In paragraph 4, The housing includes a first space portion and a second space portion partitioned by a bulkhead, and a boss portion arranged along the perimeter of a hole connecting the first space portion and the second space portion, The above sub-gear is rotatably arranged in the hole, The above shield is a sensor device including a first surface that contacts the outer surface of the boss portion.

10. In paragraph 9, The above extension is a sensor device that comes into contact with the bulkhead.

11. In paragraph 9, The above housing includes a protrusion protruding from the bulkhead, The above flange is a sensor device including a hole into which the above protrusion is inserted.

12. In paragraph 9, A sensor device in which the axial length of the above boss portion is smaller than the axial length of the above body.

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