Fixing structure for automotive components

Abstract

This invention provides a fixing structure for automotive components (e.g., magnetic components) with improved slip resistance. [Solution] The magnetic component 10 comprises at least a coil 4, a ferrite core 3, and a leaf spring 2 that presses the upper surface 30 of the ferrite core 3 against the housing 1 with elastic force. The upper surface 30 of the ferrite core 3 has a groove 31 extending in a direction intersecting the front-rear direction of the vehicle (the direction in which the vehicle moves forward and backward). The inner wall surface of the groove 31 is inclined, and the protruding portion 21 of the leaf spring 2 has a rounded R shape. The R-shaped tip portion 20 of the leaf spring 2 is pressed against the opposing inclined wall surfaces 32a and 32b, respectively, thus fixing the magnetic component at two locations 20a and 20b. The groove may also have a groove 35 extending in a direction intersecting the left-right direction of the vehicle (the direction in which the vehicle rotates), and inclined wall surfaces 36a and 36b may be formed in the same manner as described above.

Description

Technical Field

[0001] The present invention relates to a hybrid vehicle or an electric vehicle equipped with an inverter, and relates to a fixing structure of in-vehicle components such as a transformer and a choke coil used in the inverter.

Background Art

[0002] A hybrid vehicle or an electric vehicle has a DC power source, an inverter, and a motor driven by the inverter, and converts the DC voltage from the DC power source into an AC voltage by the inverter, and rotates the motor by the converted AC voltage to obtain a power source. The power conversion device of the inverter includes various in-vehicle components including magnetic components such as a transformer and a choke coil. Hereinafter, the present invention will be described by taking a magnetic component as an example. Generally, these magnetic components are composed of a coil and a core made of a magnetic material, and the core often uses a core made of a ferrite magnetic material (hereinafter referred to as a ferrite core).

[0003] Normally, external forces such as impacts transmitted from the traveling road and vibrations from the drive source are applied to the vehicle body. In particular, large external forces such as large vibrations are applied to the power conversion device of the inverter installed near the engine. It is necessary to securely fix the core of the magnetic component so as not to come off due to the large external force. Therefore, the following proposals have been made regarding the fixing structure of the ferrite core constituting the magnetic component.

[0004] Patent Document 1 discloses a fixing structure for fixing the core of a magnetic component, in which the upper surface of the ferrite core is pressed and fixed with an elastic member such as a leaf spring.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

[0006] Vibrations and shocks acting on the vehicle body occur in all directions: the longitudinal direction (the direction in which the vehicle moves forward and backward), the lateral direction (the direction in which the vehicle rotates), and the vertical direction (the direction in which the vehicle bounces). The fixing structure described in Patent Document 1 is relatively simple and allows for a large pressing pressure. However, the ferrite core is weak against shear stress caused by the pressing and may crack. Also, as the spring constant increases, assembly becomes more difficult, and components such as leaf springs cannot be changed arbitrarily. Therefore, it is necessary to adjust the pressing force using a predetermined leaf spring. However, in the fixing structure of Patent Document 1, since there is surface contact between the ferrite core and the leaf spring, slippage may occur between them depending on the external forces acting on the vehicle in the longitudinal or lateral directions. For these reasons, it is desirable to take measures to prevent slippage.

[0007] This invention was made in view of the above-mentioned technical problems, and the object of this invention is to provide a fixing structure for automotive components that improves slip resistance (slip resistance) even with a simple structure. [Means for solving the problem]

[0008] To achieve the above objective, the present invention provides a fixing structure for an on-board component that is placed on a predetermined flat location in a vehicle, by applying an elastic force toward the flat surface of the on-board component toward the flat location, wherein the flat surface has a recessed groove formed in a direction perpendicular to the flat surface, and has an elastic leaf spring, and the leaf spring is provided with a protrusion that fits into the recessed groove and is pressed against the inner surface of the recessed groove, and the protrusion fits into the recessed groove and engages in the planar direction of the flat surface of the on-board component. [Effects of the Invention]

[0009] External forces acting on the vehicle body are primarily concentrated in the longitudinal (vehicle's forward and backward movement) and vertical (vehicle's bouncing) directions. However, from the standpoint of slip resistance, it is desirable to improve slip resistance in both the longitudinal and lateral directions (vehicle's rotational direction). Therefore, to obtain slip resistance against longitudinal external forces, a groove extending in a direction intersecting the longitudinal direction is formed, and the protruding portion of the leaf spring is engaged with this groove (in this invention, engagement includes the form in which it fits and is pressed against the inner surface of the groove). In other words, the protruding portion of the leaf spring is hooked into the groove. This provides resistance (slip resistance) particularly against longitudinal external forces, and can restrain the vehicle's components from moving. On the other hand, to obtain slip resistance against lateral external forces, a groove extending in a direction intersecting the lateral direction is formed, and the protruding portion of the leaf spring is engaged with this groove and hooked in the same manner. This allows for engagement in the planar direction of a flat surface, providing resistance (slip resistance) particularly against external forces in the lateral direction, and effectively restraining the vehicle component from moving. As described above, the present invention can provide a fixing structure for in-vehicle components that improves slip resistance (slip resistance) even with a simple structure. [Brief explanation of the drawing]

[0010] [Figure 1] This is a cross-sectional view showing an overview of an in-vehicle component (magnetic component) of one embodiment of the present invention. [Figure 2] This is a schematic diagram showing a groove formed in a ferrite core, which is part of a fixing structure according to one embodiment of the present invention. [Figure 3] This is a schematic diagram showing the engagement state between a ferrite core and a leaf spring in one embodiment of the present invention. [Figure 4] This is a schematic diagram illustrating another example of a groove in a fixed structure according to one embodiment of the present invention. [Modes for carrying out the invention]

[0011] Embodiments of the present invention will be described with reference to the accompanying drawings. In the following embodiments, a magnetic component such as a choke coil used in a vehicle equipped with an inverter will be described as an on-board component placed on a predetermined flat location in the vehicle. Note that the embodiments described below are merely examples of how the present invention can be implemented and do not limit the present invention.

[0012] Figure 1 is a cross-sectional view showing an overview of a magnetic component 10 according to one embodiment. Figure 2 shows the fixing structure of Figure 1, and is a schematic diagram showing a groove 31 formed in the ferrite core 3. Figure 3 is a schematic diagram showing the engagement state between the ferrite core 3 and the protrusion 21 of the leaf spring 2. Figure 4 is a schematic diagram showing another example of a groove 35 formed in the ferrite core 3.

[0013] The magnetic component 10 shown in Figure 1 is a power conversion device within an inverter, such as a choke coil, and is installed near the vehicle's engine. This magnetic component comprises at least a coil 4 that generates magnetic flux when energized, a ferrite core 3 that forms a magnetic path for the magnetic flux, a housing 1 that supports the ferrite core 3, and a leaf spring 2 that fixes the ferrite core 3 to the housing 1.

[0014] Coil 4 is composed of, for example, a coil with a rectangular cross-section, and generates magnetic flux when energized. To allow a large current to flow stably through coil 4, the cross-sectional area of ​​the coil's winding (rectangular wire) is large. Terminals (not shown) for conducting current through coil 4 are provided at both ends of coil 4.

[0015] The ferrite core 3 consists of a pair of cores, an upper ferrite core 3a and a lower ferrite core 3b, both with an "E" shaped cross-section, and is made of ferrite magnetic material. The upper and lower ferrite cores 3a and 3b are positioned in predetermined locations on the housing 1 and cover most of the winding portion of the coil 4. Thus, the ferrite core 3 forms a magnetic path for the magnetic flux generated from the coil 4. A bobbin 5 is provided between the ferrite core 3 and the coil 4. The bobbin 5 is made of a synthetic resin insulator and insulates the ferrite core 3 from the coil 4.

[0016] In this embodiment, the flat surface (top surface) 30 of the upper ferrite core 3a has grooves on the left and right sides of the paper, and a groove 31 is formed that extends toward the back of the paper. Bases 7 are erected on the left and right sides of the ferrite core 3 on the housing 1. The protruding portion 21 of the leaf spring 2 is engaged with the grooves 31 on the left and right so as to catch in the grooves, and the leaf spring 2 is then attached to the bases 7 with bolts 6. This allows the ferrite core 3 to be firmly fixed to the housing 1. As in this embodiment, by forming grooves 31 on the flat surface (top surface) 30 of the ferrite core 3 and creating a structure in which the protruding portion 21 of the leaf spring 2 is caught in these grooves 31, the resistance to external forces in the vertical and horizontal directions is increased, and the slip resistance is improved. The shape of the protruding portion 21 is not limited as long as it engages with the grooves, that is, as a shape that catches. The details of the engagement between the ferrite core 3 and the leaf spring 2 will be explained below with reference to Figures 2 and 3.

[0017] The groove 31 formed in the upper ferrite core 3a is a long groove extending in the longitudinal direction of the upper ferrite core 3a, and it is desirable that its wall surface be an inclined wall surface (see inclined wall surfaces 32a and 32b in Figure 2). In cross-section, it is formed in the shape of a V-notch. The notch angle is preferably 90°, but it can be set as appropriate, such as 60° or 120°. The ferrite core is made of a sintered body, and the V-notch can be integrally molded during sintering. However, it may also be formed by machining.

[0018] The leaf spring 2 comprises a fixing portion 23 for attaching a fastening member such as a bolt, a substantially "H" - shaped arm portion 22 that exhibits a predetermined elastic force (spring force), and a protruding portion 21 that fits into the above - mentioned concave groove 31. The protruding portion 21 may have a shape that engages (or in other words, hooks) in the concave groove to exhibit a resistance force. The fixing portion 23 is fixed to the pedestal 7 via bolts 6 etc., and the width and thickness of the arm portion 22 are set so that a predetermined elastic force (spring force) is generated. For example, the width of the protruding portion 21 can be set to a width that fits across substantially the entire length of the concave groove 31. And, as an example, the cross - section of the protruding portion 21 is an R - shaped cross - section with rounded corners, and it becomes an R - shaped tip portion 20 that abuts against the respective opposing inclined wall surfaces in the concave groove 31, that is, the inclined wall surfaces 32a and 32b. Since it is an R - shape, even if the dimensions of the R, the angle and dimensions on the V - notch side deviate somewhat, the contact with the opposing inclined wall surfaces is maintained. Incidentally, the leaf spring 2 is made of a spring steel material such as stainless steel or carbon steel, and appropriate molding and heat treatment can be performed.

[0019] As described above, when the protruding portion 21 of the leaf spring 2 is engaged in the concave groove 31 formed on the upper surface 30 of the upper ferrite core 3a, the R - shaped tip portion 20 abuts against the opposing inclined wall surfaces 32a and 32b, and in terms of cross - section, contact occurs at two locations, 20a and 20b (see Fig. 3). Then, by fastening the fixing portion of the leaf spring 2 to the pedestal 7 of the housing 1 with bolts 6, an elastic force acts on the two contact points 20a and 20b of the R - shaped tip portion 20, and the ferrite core 3a can be firmly fixed by pressing it downward. Also, in this embodiment, since the leaf springs 2 are attached to the opposing left and right pedestals 7 in an opposing manner, the ferrite core 3 can be fixed to the housing 1 in a balanced manner even when using relatively weak spring plates.

[0020] Next, FIG. 2 shows an example of the direction of the external force applied to the vehicle and the direction in which the concave groove is formed. In this example, a concave groove 31 extending in a direction intersecting the longitudinal direction X of the vehicle (in other words, a direction intersecting the forward and backward direction of the vehicle) is formed. Further, in this example, the concave groove 31 is provided at substantially the center of the upper surface 30 of the upper ferrite core 3a, and the protruding portion 21 of the leaf spring 2 is engaged in the concave groove 31. Also, the opposing wall surfaces within the concave groove 31 are inclined wall surfaces 32a and 32b, which are formed in a V-notch shape when viewed in cross-section. Here, the notch angle is preferably 90°, but it may be appropriately selected such as 60° or 120°. Also, the opposing wall surfaces in the short side direction may be inclined wall surfaces 33a and 33b, but there are no particular restrictions. Therefore, by engaging the protruding portion 21 of the leaf spring 2 in the concave groove 31, the R-shaped tip 20 is caught by and pressed against the inclined wall surfaces 32a and 32b, and the movement in the longitudinal direction is restricted. Thus, even when an external force is applied in the longitudinal direction, the ferrite core 3 does not shift, and the ferrite core can be firmly fixed. In this example, particularly, the anti-slip property with respect to the longitudinal direction X of the vehicle is improved.

[0021] FIG. 3 is a schematic diagram showing the engagement state between the ferrite core 3 (3a) and the leaf spring 2, and shows the press contact at two locations and the dispersion of the external force. By engaging the R-shaped tip 20 of the protruding portion 21 of the leaf spring 2 in the concave groove 31 in this way, in a cross-sectional view, the R-shaped tip 20 is press-contacting two locations, namely, locations 20a and 20b on the opposing inclined wall surfaces 32a and 32b, respectively. Therefore, in the present invention, the pressing force is applied to two opposing locations instead of pressing on one surface as in the prior art, so that the protruding portion 21 becomes difficult to come out of the concave groove, and the resistance force (anti-slip force) in the sliding direction increases. On the other hand, when viewed from the side of the external force F due to vibration or impact force, the external force F acting on the inclined wall surfaces 32a and 32b is dispersed into a force Fv perpendicular to the inclined wall surface and a force Fp parallel to the inclined wall surface. By dispersing the external force, the sliding force is weakened, and displacement is less likely to occur.

[0022] As described above, the external forces applied to the vehicle are large in the longitudinal direction (the direction in which the vehicle moves forward and backward) and the vertical direction (the direction in which the vehicle bounces). However, the vertical direction Z can be suppressed by the compressive force of the leaf spring, so from the viewpoint of slip resistance, it is desirable to improve the slip resistance in the longitudinal direction and the lateral direction (the direction in which the vehicle rotates). For this reason, if slip resistance is to be obtained against external forces in the longitudinal direction, it is desirable to use the embodiment shown in Figure 3 above. On the other hand, if slip resistance is to be obtained in particular against external forces in the lateral direction, it is good to form a groove 35 that extends in a direction intersecting the lateral direction Y of the vehicle (in other words, in a direction intersecting the direction in which the vehicle rotates), as shown in Figure 4. In this embodiment, a groove 35 is formed that extends in a direction intersecting the lateral direction, the opposing wall surfaces are inclined wall surfaces 36a and 36b, and the R-shaped tip 20 of the leaf spring 2 is engaged with each of these inclined wall surfaces 36a and 36b. Furthermore, since the compressive force of the leaf spring is greater than the external force in the vertical Z direction, there are fewer problems regarding slip resistance.

[0023] To summarize the embodiments shown in Figures 1 to 4, the magnetic component 10 comprises at least a coil 4, a ferrite core 3, and a leaf spring 2 that elastically presses against the flat surface (upper surface) 30 of the ferrite core 3 to fix it to the housing 1. The upper surface 30 of the upper ferrite core 3a has a groove 31 extending in a direction intersecting the front-rear direction of the vehicle or a groove 35 extending in a direction intersecting the left-right direction of the vehicle. The walls of these grooves 31 and 35 are inclined, and the protruding tip 21 of the leaf spring 2 has a rounded R shape. The R-shaped tip 20 of the leaf spring 2 is pressed against the opposing inclined wall surfaces 32a, 32b and 36a, 36b, respectively, in this magnetic component fixing structure.

[0024] It should be noted that the present invention is not limited to the embodiments described above and can be modified as needed. For example, the engagement length between the groove and the projection of the leaf spring can be set as appropriate. It is advantageous for slip resistance to make the engagement as long as possible, along the entire length. However, it is desirable to adjust it to the extent that it does not cause problems with assembly. In addition, in some cases, both grooves may be provided, one extending in a direction intersecting the front-rear direction of the vehicle and another extending in a direction intersecting the left-right direction of the vehicle, and fixed with the same leaf spring. That is, a structure in which the ferrite core is pressed and fixed from two directions may be used. Furthermore, the wall surface in the short direction of the groove may be an inclined surface or a vertical surface, and its shape is not restricted. In addition, it is desirable that the projection of the leaf spring has a rounded R shape, but it is acceptable as long as it is in a shape that is pressed against the inclined wall surface. For example, a form in which a part of the tip protrudes in two places and is pressed against in two places, or a curved form may be considered. In addition, although an example of a magnetic component consisting of a choke coil has been shown in this embodiment, the present invention can also be applied to other magnetic components such as transformers. [Explanation of Symbols]

[0025] 1: Cabinet 2: Leaf spring (elastic member) 3: Ferrite core 3a: Upper ferrite core 3b: Lower ferrite core 4: Coil 5: Bobbin 6: Bolt 7: Pedestal 10: Magnetic components 20: R-shaped tip 20a, 20b: Pressure welding points 21:Protrusion 22: Arm 23: Fixed part 30: Flat surface (top surface) of the ferrite core 31, 35: Recessed groove 32a, 32b, 36a, 36b: Slanted wall surface

Claims

[Claim 1] A vehicle component fixing structure that fixes a vehicle component placed on a predetermined flat location in a vehicle by applying an elastic force to the flat surface of the vehicle component toward the flat location, A groove is formed in the flat surface, in a direction perpendicular to the flat surface. It has an elastic leaf spring, and the leaf spring is provided with a protrusion that fits into the groove and is pressed against the inner surface of the groove. A fixing structure for an in-vehicle component, characterized in that the protruding portion fits into the groove and engages in the planar direction of the flat surface of the in-vehicle component.

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