JPH02252962A - Installation structure for motor-driven fuel pump - Google Patents

Abstract

PURPOSE:To suppress noise by installing at least a part of a bracket so as to surround the side surface of a pump which is set close to an outlet part side part position, when a motor-driven fuel pump is installed in a fuel tank through the bracket. CONSTITUTION:A cylindrical electromagnetic fuel pump 1 is installed in erection state through a bracket B in a subtank S installed inside a fuel tank T of an automobile, and the bracket B whose upper edge is fixed onto the upper part of the fuel tank T is constituted of a vertical part B1 which extends downward in the nearly vertical direction along the side surface of the pump 1 and a horizontal part B2 which is bent at right angles at the lower edge of the vertical part B1 and extends in the nearly horizontal direction. The vertical part B1 is formed wider than that in the conventional, so as to surround the side surface of the pump 1 over the range in an angle theta in the circumferential direction, having each radius which passes through the collision points P and Q where fuel collides with the partitioning part in the case when fuel passes through each outlet hole 25, 28, as center.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) This invention relates to a mounting structure for an electric, dynamic fuel pump installed in a vehicle, etc., and more specifically, an in-tank type electric fuel pump installed in a fuel tank of a vehicle, etc. Regarding the mounting structure of the fuel pump.

(Prior Art) A conventional electric fuel pump mounting structure will be described with reference to FIG. 1 (common to the embodiments of the present invention described later) and FIGS. 5 to 11.

In FIG. 1, a cylindrical electric fuel pump 1 is a sub-tank S provided inside a fuel tank T of a vehicle, for example, an automobile.
It is mounted upright inside via bracket B. The bracket B has an upper end fixed to the upper part of the fuel tank T, and has a vertical part B1 that extends downward in a substantially vertical direction along the side of the electric fuel pump 1, and a vertical part B1 that is bent at a right angle at the lower end of the vertical part B1 and is substantially horizontal. It has a horizontal portion B2 extending in the direction.

The electric fuel pump 1 is connected to this horizontal portion B as shown in FIG.
2 from below, and in this state, a fuel inlet hole 24, which will be described later, provided at the lower end is in close proximity to the bottom surface of the tank T. In addition, the inlet hole 24 has a filter F.
is installed.

Next, to explain the configuration of the electric fuel pump 1, as shown in FIG. The shaft 5a of the armature 5 is located approximately at the center inside the casing 2.
are supported at their upper and lower ends via bearings 6 and 7. A pair of magnets 8.8 are fixed to the inner surface of the casing 2 at a predetermined gap from the armature 5, and the motor cover 3 has a brush 10 and an external connection terminal 11 for energizing the commutator 9 of the armature 5. and are attached via holders 12 and 13, respectively.

The armature 5, magnets 8, 8, commutator 9, brush 10, and external connection terminal 11 constitute a motor section 15 for driving a pump section 14 disposed below the armature 5.

The pump part 14 is connected to the lower end of the shaft 5a of the armature 5 and is rotatably driven by a first impeller 16 having the same configuration.
and a second impeller 17, and these impellers 16.17
and a pump casing 18 surrounding the pump. The pump casing 18 includes the pump cover 4, a pump body 20 fixed to the pump cover 4 via a plurality of screws 19 (only one is shown in the drawing), an annular first spacer 21, an annular plate 22, and an annular first spacer 21. The second spacer 23 (
(same configuration as the first spacer 21). Here, the plate 22 and the pump body 20 form an axial wall surrounding the first impeller 16, the first spacer 21 forms a radial wall surrounding the first impeller 16, and the pump cover 4 and the plate 22 are arranged so that the wall in the axial direction surrounding the second impeller 17 is connected to the second spacer 23.
form a radial wall portion surrounding the second impeller 17, respectively. Also, Bo, Nbu body 20 and plate 2
2, a flow path in the circumferential direction between an inlet hole 24 provided in the pump body 20 and a first outlet hole 25 provided in the plate 22, at a portion of the outer periphery of the first impeller 16 facing the blade 16a. Grooves 2Qa and 22a (see FIG. 7) are provided respectively to form a first flow path 26 with the inner peripheral surface of the first spacer 21.
As shown in FIG. 8, a partition portion 27 extending radially inward is provided between the inlet hole 24 on the side where the flow path 26 is not provided and the first outlet hole 25 to partition the gap between them. On the other hand, the plate 22 and the pump cover 4 have a circular shape between the first outlet hole 25 of the plate 22 and the second outlet hole 28 provided in the pump cover 4 at a portion facing the blade 17a on the outer periphery of the second impeller 17. Circumferential channel groove 2
2b.

4a (see FIG. 9) are provided to form a second flow path 29 with the inner peripheral surface of the second spacer 23, and the second spacer 23 has a second flow path 29 on the side where the second flow path 29 is not provided. As shown in FIG. 10, a partition portion 30 extending radially inward is provided between the first exit hole 25 and the second exit hole 28 to partition the two.

In such an electric pump 1, when the motor section 15 is energized via the external connection terminal 11 from a battery (not shown) and the armature 5 is rotated, the first impeller 16 and the second impeller 17 of the pump section 14 are rotated accordingly. Rotate. As a result, the fuel in the fuel tank T is pumped up into the pump casing 18 from the inlet hole 24 via the filter F, and the fuel passes through the first flow path 26 and enters the second flow path 29 from the first outlet hole 25. From there, it enters the casing 2 through the second outlet hole 28, is discharged to the outside through the discharge port 33, and is supplied to an engine (not shown).

Conventionally, such an electric fuel pump 1 is
As shown in FIG. 11, which is a cross section taken along line I (the cross section of the electric fuel pump 1 shown in the same figure corresponds to the cross section taken along line M-M in FIG. 6), and FIG. Top, entrance hole 2
4 is mounted on the side closer to the bracket F, that is, on the opposite side of the vertical portion B1 of the bracket B.

(Problems to be Solved by the Invention) Incidentally, in such an electric fuel pump 1, when fuel flows inside the pump casing 18, noise in a high frequency band determined by the number of impeller blades x the number of rotations of the impeller is generated, and this Such noises occur at points a, b, and c in each direction perpendicular to each other in FIG.

As is clear from FIG. 12 shown in connection with d, it is known that the fuel becomes largest at the point P where it collides with the corresponding partition 27 when passing through the first outlet hole 25 (12th The data in the figure is when the sound pressure was measured in liquid using the electric fuel pump 1 alone). Although FIG. 11 only shows the first channel 26 in the first stage, the same applies to the two second channels in the second stage, and only the point of collision with the partition 30 is shown in the figure. is denoted by Q.

In the conventional mounting structure of the electric fuel pump 1 described above, although the vertical part B1 of the bracket B surrounds a part of the side surface of the electric fuel pump 1, as is clear from FIG. Since the side surface on the side where the collision point with P and Q exists is free, most of the sound emitted radially from each collision point P and Q goes straight to the nab tank S.
Furthermore, the noise is transmitted to the wall of the main fuel tank T, resulting in increased noise.

(Means for Solving the Problems) A mounting structure for an electric fuel pump of the present invention includes an impeller that is rotationally driven by a motor section, and a pump casing that surrounds the impeller, and the pump casing is arranged by a partition section. An inlet part and an outlet part provided at appropriate positions in the circumferential direction, and a circumferential flow path extending from the inlet part to the outlet part surrounding the blades provided on the outer periphery of the impeller. An electric fuel pump mounting structure in which an electric fuel pump is supported within a fuel tank via a bracket, wherein at least a part of the bracket is close to a portion of the partition portion on the outlet side. The electric fuel pump is configured to include and surround a side surface of the electric fuel pump.

(Function) In the mounting structure of the electric fuel pump of the present invention, the side surface of the electric fuel pump is surrounded by the bracket at the portion near the outlet side of the partition where the noise is the loudest. The sound generated by the fuel colliding with the part on the outlet side hits a part of the bracket and is absorbed by this, and the reflected sound is dispersed in direction by the bracket.

(Example) Next, an example of the present invention will be described with reference to FIGS. 1 to 4.

Note that this embodiment uses an electric fuel pump 1 similar to the conventional example described above.
This relates to the mounting structure when the is assembled into a similar fuel tank T, and since the explanation related to FIG. will be added and the explanation will be omitted.

In FIG. 2, which corresponds to FIG. 11 of the conventional example, the bracket B of this embodiment has a vertical portion B1a that is wider than the vertical portion B1 of the conventional example. This vertical portion B1a extends from the side surface of the electric fuel pump 1 over an angle θ in the circumferential direction centered on the radius passing through each of the fuel collision points P and Q of the partition portion 27 and the partition portion 30 in the electric fuel pump 1. surround 1
I'm reading.

Such an angle θ is set appropriately depending on the level of noise generated at each portion of the collision points P and Q, and the loudest noise generated at the collision points P and Q of the electric fuel pump 1 is determined by the vertical angle of the bracket B. The noise that collides with the portion Bla and is absorbed is attenuated, and the noise that is reflected by a portion of the vertical portion B1a is also dispersed in direction as shown in FIG. Furthermore, the noise transmitted to the fuel tank T is reduced as a whole.

Furthermore, due to the installation of the electric fuel pump 1 as described above, the position of the inlet hole 24 will be located closer to the bracket B as shown in FIG.
has a horizontal portion as shown at 82a in FIG. 3, unlike the conventional horizontal portion 82, and also has an inlet pipe portion F1 of the filter F.
is longer than that of the conventional example.

Next, a second embodiment of the present invention will be described with reference to FIG.

This embodiment is a modification of the first embodiment, and in the figure, an elastic member 32 such as rubber is provided on the inner surface of the vertical portion B1a of the bracket B, which is similar to the first embodiment, and faces the side surface of the electric fuel pump 1. is installed. By providing such an elastic member 32, the noise generated at each of the collision points P and Q is absorbed by the elastic member 32, and reflection from the elastic member 32 is prevented, thereby further reducing noise. can be done.

Furthermore, separately, the noise can be further reduced by forming the bracket B from a static vibration steel plate or by forming irregularities on the surface of the vertical portion B1a of the bracket B.

(Effects) In the electric fuel pump mounting structure of the present invention, the sound generated by the fuel colliding with the outlet side of the partition hits a part of the bracket and is absorbed by the bracket, and the reflected sound is absorbed by the bracket. Since the directions are dispersed, the sound transmitted to the fuel tank is alleviated and the noise is reduced, which has the advantage that the noise transmitted to the vehicle etc. in which it is mounted is further reduced.

[Brief explanation of drawings]

1 to 3 show a mounting structure of an electric fuel pump according to a first embodiment of the present invention, and FIG. 1 is a front view showing the internal structure of a fuel tank of a vehicle, which is a common view with the conventional example. 2 is a sectional view taken along the line II-IIX of FIG. 1; FIG. 3 is a bottom view of FIG. 2 with the sub-tank removed; FIG. 4 is a second sectional view showing the mounting structure of the electric fuel pump according to the second embodiment 5 to 12 show conventional examples, and FIG. 5 is a bottom view corresponding to FIG. 3 of the conventional electric fuel pump mounting structure, and FIG. 6 is an electric fuel pump mounting structure. A vertical cross-sectional view of the pump, Fig. 7 is an enlarged view of section A in Fig. 6, Fig. 8 is a cross-sectional view taken along ■-■ of Fig. 6,
Figure 9 is an enlarged view of part B in Figure 6, and Figure 10 is an enlarged view of section B in Figure 6.
An X-ray cross-sectional view, FIG. 11 is a cross-sectional view taken along the Xl-XI line in FIG.
Figure 12 shows the sound pressure in the liquid of the electric fuel pump from a to Figure 11.
It is a figure which shows the data measured in each direction of b. 1... Electric fuel pump 16... First impeller 17... Second impeller 18... Pump casing 24... Inlet hole 25... First outlet hole 26.29... Channel 28 ...Second outlet hole■...Fuel tank S...Sub tank B...Bracket B1...Vertical part Fig. 1

Claims (1)

[Claims] It has an impeller rotationally driven by a motor section, and a pump casing surrounding the impeller, and the pump casing has an inlet section and an outlet section provided at appropriate positions in the circumferential direction by a partition section, and An electric fuel pump comprising a circumferential flow path surrounding a blade provided on the outer periphery of an impeller and extending from the inlet to the outlet is supported in a fuel tank via a bracket. The electric fuel pump mounting structure is characterized in that at least a part of the bracket is configured to include and surround a side surface of the electric fuel pump that is close to a portion of the partition on the outlet side. Mounting structure of electric fuel pump.