Fuel supply device

Abstract

The present application provides a fuel supply device capable of suppressing metal fatigue of a pigtail.　The fuel supply device comprises: a housing (11) having one end side coupled to a bracket (12) and the other end side coupled to a pump casing assembly (1) and internally stores a rotor (8); a power supply terminal (16) disposed inside the bracket (12) and externally supplied with electric power; and a brush (18) disposed inside the bracket (12) and coupled to the power supply terminal (16). A pigtail (17) having one side fixed to a fixing part (16a) of the power supply terminal (16) and the other side fixed to the brush (18) is provided. An axis G of the pigtail (17) is positioned in a perpendicular direction with respect to a direction of a vertical behavior of the brush (18). An extension of the axis G of the pigtail (17) intersects a center part of a range S of the vertical behavior of the brush (18).

Description

fuel supply device

[0001] The present application relates to a fuel supply system.

[0002] Conventional fuel supply devices are immersed in fuel tanks to supply fuel to internal combustion engines mounted on various vehicles. In recent years, there has been a trend toward high vibration levels in vehicles, particularly in motorcycles. When the vibration levels generated by the vehicle are high, the vibrations are transmitted to the rotor inside the fuel supply device mounted inside the fuel tank, causing the brushes to move up and down due to the rotor's oscillation.

[0003] 5, the pigtail 117, which is fixed integrally with the brush 118, bends in accordance with the up and down movement of the brush 118, but the fixing portion 116a of the power supply terminal 116, which fixes the power supply terminal 116 to the pigtail 117, becomes the starting point of bending, and stress is concentrated thereon. Therefore, if the pigtail 117 is subjected to up and down movement due to excessive vibration or frequent movement due to excessive vibration, metal fatigue may occur in the pigtail 117.

[0004] Japanese Patent Application Publication No. 3-199693

[0005] In the conventional fuel supply device described above, pigtail 117, which is fixed integrally with brush 118, is a path for applying an external voltage to the rotor. Therefore, if pigtail 117 is subjected to frequent movements due to the up and down movements or excessive vibration of brush 118, metal fatigue may occur in pigtail 117, which may lead to wire breakage and cause the fuel supply device to stop operating.

[0006] To solve this problem and prevent stress concentration when the pigtail 117 is bent, it is possible to secure a margin against metal fatigue by changing the lead-out structure of the pigtail 117 and increasing the radius of curvature as much as possible, as shown in Figure 6. However, because the pigtail 117 is routed in a limited space inside the bracket, it is difficult to change the lead-out structure while maintaining the current size.

[0007] The present application has been made to solve the above-mentioned problems, and has an object to provide a fuel supply device that can suppress metal fatigue of the pigtail.

[0008] The fuel supply device disclosed in the present application includes a pump casing assembly having an impeller built in, a housing having a bracket connected to one end and the pump casing assembly connected to the other end and containing a rotor inside, a bracket connected to the other end of the rotor, a power supply terminal disposed inside the bracket and supplied with power from an external source, and a brush disposed inside the bracket and connected to the power supply terminal, and a pigtail is provided having one side fixed to a fixing portion of the power supply terminal and the other side fixed to the brush, the axis of the pigtail being positioned perpendicular to the direction of up and down movement of the brush, and the extension of the axis of the pigtail intersects with the center of the range of up and down movement of the brush.

[0009] According to the fuel supply device disclosed in the present application, it is possible to obtain a fuel supply device characterized by having a structure that has a tolerance for metal fatigue of the pigtail.

[0010] Fig. 1 is a cross-sectional view showing a fuel supply device according to a first embodiment of the present application; Fig. 2 is a cross-sectional view showing the behavior of a brush and a pigtail in a fuel supply device according to a first embodiment of the present application; Fig. 3 is a cross-sectional view showing the behavior of a brush and a pigtail in a fuel supply device according to a second embodiment of the present application; Fig. 4 is a cross-sectional view showing the behavior of a brush and a pigtail in a fuel supply device according to a third embodiment of the present application; Fig. 5 is a cross-sectional view showing the behavior of a brush and a pigtail in a conventional fuel supply device; Fig. 6 is a cross-sectional view showing the behavior of a brush and a pigtail in another conventional fuel supply device.

[0011] Embodiment 1. Hereinafter, a first embodiment of the present invention will be described with reference to Figures 1 to 3, and the same or corresponding members and parts in each figure will be described with the same reference numerals. Figure 1 is a cross-sectional view showing a fuel supply device according to the first embodiment of the present invention. Figure 2 is a cross-sectional view showing the behavior of a brush and a pigtail in the fuel supply device according to the first embodiment of the present invention.

[0012] 1, pump casing assembly 1 is made up of pump casing body 2 and cover 3. An impeller 4 having blades 5 on its outer periphery is provided inside pump casing assembly 1. Impeller 4 is rotatably supported within pump casing assembly 1 by the central shaft 6 of a rotor 8. The central shaft 6 of impeller 4 also serves as the central shaft of rotor 8 of electric motor 7, and both ends of the central shaft 6 are rotatably supported by bearings 9 and 10.

[0013] The cylindrical housing 11 also serves as a yoke for the electric motor 7, and is fitted and connected to a bracket 12 made of, for example, synthetic resin at one end, and to the pump casing assembly 1 at the other end.

[0014] The housing 11 accommodates the rotor 8 inside, and has a permanent magnet 13 attached to its inner periphery, which acts as a stator. The bracket 12 is press-fitted into the housing 11 to regulate its radial position, and the bearing 10 is press-fitted into the bracket 12. The housing 11 also includes a check valve 14, a liquid outlet 15, etc., and the housing 11 and bracket 12 are fixed together as a single unit by curling the curled portion formed on the edge of the housing 11.

[0015] A power supply terminal 16 for supplying power from an external source is attached to the bracket 12, and a pigtail 17 is fixed so as to be electrically connected to the power supply terminal 16, and a brush 18 is fixed integrally with the pigtail 17. The brush 18 is structured so as to slide against and abut on a commutator 19 located on the top of the rotor 8 housed inside the housing 11.

[0016] Next, operation will be described. In the fuel supply device configured as described above, an externally applied voltage is applied from power supply terminal 16 to pigtail 17, from pigtail 17 to brush 18, and from brush 18 to commutator 19 to rotor 8. When current is applied to rotor 8, it rotates. This rotation of rotor 8 rotates impeller 4, and liquid fuel is drawn in through intake port 20. The liquid fuel pressurized by the rotational force of impeller 4 passes through the inside of the fuel supply device and is supplied to the internal combustion engine through liquid outlet 15 provided in bracket 12.

[0017] As shown in FIG. 2 , in the present application, the fixing portion 16 a of the power supply terminal 16 is provided to fix the power supply terminal 16 and the pigtail 17 so as to be electrically conductive, and the fixing portion 16 a of the power supply terminal 16 has a relative angle such that the axis G of the pigtail 17 fixed by the fixing portion 16 a of the power supply terminal 16 is drawn out in a direction approximately perpendicular to the direction in which the brush 18 moves.

[0018] The fixing portion 16a of the power supply terminal 16 is configured so that the axis G of the pigtail 17 can be positioned at an angle where an extension of the axis G of the pigtail 17 intersects with approximately the center of the range S that indicates the up and down movement of the brush 18.

[0019] At this time, the fixing portion 16a of the power supply terminal 16 can be fixed to the pigtail 17 so that the power supply terminal 16 and the pigtail 17 can be electrically connected by, for example, fixing the fixing portion 16a of the power supply terminal 16 by crimping so as to bend the fixing portion 16a so as to sandwich the pigtail 17, or by welding the fixing portion 16a of the power supply terminal 16 to the pigtail 17.

[0020] With this configuration, when the brush 18 moves up and down, the curvature can be reduced by having no bent portion of the pigtail 17. Also, by setting the relative angle such that the pigtail 17 moves up and down from approximately the center of the range S in which the brush 18 moves up and down, the curvature that occurs when the pigtail 17 moves can be suppressed, and a routing structure for the pigtail 17 that has a tolerance for metal fatigue can be achieved.

[0021] Embodiment 2. A second embodiment of the present invention will be described with reference to Figure 3, in which the same or corresponding members and parts are denoted by the same reference numerals. Figure 3 is an enlarged side view of a main part showing the behavior of the brush and pigtail in a fuel supply device according to the second embodiment of the present invention.

[0022] The second embodiment of the present invention has the same structure as the first embodiment of the present invention shown in FIG. 2 , but in order to configure the fixing portion 16 a so that the axis G of the pigtail 17 can be positioned at an angle where an extension of the axis G of the pigtail 17 intersects with approximately the center of the range S that indicates the up and down movement of the brush 18, the fixing portion 16 a provided on the power supply terminal 16 may be configured with an angle changed to match the axis G of the pigtail 17.

[0023] Embodiment 3. Embodiment 3 of the present invention will be described with reference to Figure 4. Figure 4 is an enlarged cross-sectional view of the fixing portion 16a of the power supply terminal 16 in Embodiments 1 and 2 of the present invention. As described above in Embodiment 1, the fixing portion 16a of the power supply terminal 16 is fixed by crimping so as to sandwich the pigtail 17 in order to secure the power supply terminal 16 and the pigtail 17 so that they are electrically connected. The end surface of the fixing portion 16a of the power supply terminal 16 that sandwiches the pigtail 17 is provided with a relief portion 16b chamfered at an angle δ. By following the up and down movement of the brush 18, the angle θ formed with the axis G of the pigtail 17 is set to an angle such that δ > θ.

[0024] This prevents interference between the pigtail 17 and the end face of the fixed portion 16a even at maximum movement when the pigtail 17 follows the up and down movement of the brush 18, making it possible to provide a routing structure for the pigtail 17 with a tolerance for metal fatigue.

[0025] The relief portion 16b formed by chamfering the end face of the fixed portion 16a of the power supply terminal 16 may be configured to have an R-shape. In this case, the angle formed by the tangent line drawn to the R-shape and the pigtail 17 when the brush is at its maximum movable position is defined as δ, and the R-shape satisfies the relationship δ>θ.

[0026] Although various exemplary embodiments and examples are described in this application, the various features, aspects, and functions described in one or more embodiments are not limited to the application of a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are contemplated within the scope of the technology disclosed in this specification. For example, this includes cases where at least one component is modified, added, or omitted, or where at least one component is extracted and combined with components of another embodiment.

[0027] The present application is suitable for realizing a fuel supply device that can suppress metal fatigue of the pigtail.

[0028] REFERENCE SIGNS LIST 1 Pump casing assembly, 2 Pump casing body, 3 Cover, 4 Impeller, 5 Blade portion, 6 Central shaft, 7 Electric motor, 8 Rotor, 9 Bearing, 10 Bearing, 11 Housing, 12 Bracket, 13 Permanent magnet, 14 Check valve, 15 Liquid outlet, 16 Power supply terminal, 16a Fixing portion, 16b Relief portion, 17 Pigtail, 18 Brush, 19 Commutator, 20 Inlet port

Claims

1. A fuel supply device comprising: a pump casing assembly having an impeller built therein; a housing having a bracket connected to one end thereof and the pump casing assembly connected to the other end thereof, the housing accommodating a rotor therein; a power supply terminal disposed inside the bracket and supplied with power from an external source; and a brush disposed inside the bracket and connected to the power supply terminal, a pigtail is provided, one side of which is fixed to a fixing portion of the power supply terminal and the other side of which is fixed to the brush, the axis of the pigtail being positioned perpendicular to the direction of up-and-down movement of the brush, and an extension of the axis of the pigtail intersects with the center of the range of up-and-down movement of the brush; a relief portion formed by a chamfer on an end surface of the fixed portion of the power supply terminal, the chamfered angle δ being an angle that is greater than a bending angle θ formed by the pigtail when the brush bends at its maximum speed, such that the relationship δ>θ holds.

2. A fuel supply device comprising: a pump casing assembly having an impeller built in; a housing having a bracket connected to one end thereof and the pump casing assembly connected to the other end thereof, the housing containing a rotor inside; a power supply terminal disposed inside the bracket and supplied with power from an external source; and a brush disposed inside the bracket and connected to the power supply terminal, a pigtail is provided, one side of which is fixed to a fixing portion of the power supply terminal and the other side of which is fixed to the brush, the axis of the pigtail being positioned perpendicular to the direction of up-and-down movement of the brush, and an extension of the axis of the pigtail intersects with the center of the range of up-and-down movement of the brush; a relief portion formed in an R-shape on an end surface of the fixed portion of the power supply terminal, and an angle δ of a tangent to the R-shape drawn parallel to the pigtail when the brush is at its maximum movement is larger than a bending angle θ formed by the pigtail when the brush is at its maximum movement, such that the relationship δ > θ is satisfied.

3. 3. The fuel supply device according to claim 1, wherein the fixing portion of the power supply terminal and the pigtail are fixed by crimping, thereby suppressing the curvature of the pigtail that follows the up and down movement of the brush.

4. 3. The fuel supply device according to claim 1, wherein the fixing portion of the power supply terminal and the pigtail are fixed by welding, thereby suppressing the curvature of the pigtail that follows the up and down movement of the brush.