U.S. patent application number 13/207710 was filed with the patent office on 2012-03-01 for fuel pump.
This patent application is currently assigned to DENSO CORPORATION. Invention is credited to Rihito ASAI, Motoya Ito, Hideki Koyama, Yoshitaka Wakamatsu, Toshitake Yaura.
Application Number | 20120051954 13/207710 |
Document ID | / |
Family ID | 45697537 |
Filed Date | 2012-03-01 |
United States Patent
Application |
20120051954 |
Kind Code |
A1 |
ASAI; Rihito ; et
al. |
March 1, 2012 |
FUEL PUMP
Abstract
A fuel pump includes a pump part, a motor part, a motor casing,
a motor cover, a terminal, and an electric connector part. The
terminal is electrically connectable to an external connector for
electricity supply. The electric connector part is disposed at an
end portion of the motor cover located on the opposite side from a
fitted end of the motor cover which is fitted with a housing, and
includes a side surface which is slidably in contact with the
external connector to determine a fitting position of the electric
connector part relative to the external connector, a bottom face
from which the terminal rises up, and an opening which is formed on
the side surface to communicate between inside and outside of the
electric connector part. The bottom face is an inclined surface
whose height becomes lower in a direction from generally a center
of the motor cover toward the opening.
Inventors: |
ASAI; Rihito; (Kariya-city,
JP) ; Wakamatsu; Yoshitaka; (Gamagori-city, JP)
; Koyama; Hideki; (Okazaki-city, JP) ; Ito;
Motoya; (Hekinan-city, JP) ; Yaura; Toshitake;
(Chiryu-city, JP) |
Assignee: |
DENSO CORPORATION
Kariya-city
JP
|
Family ID: |
45697537 |
Appl. No.: |
13/207710 |
Filed: |
August 11, 2011 |
Current U.S.
Class: |
417/410.1 |
Current CPC
Class: |
F02M 37/048 20130101;
H02K 5/12 20130101; H02K 5/225 20130101; H02K 5/148 20130101 |
Class at
Publication: |
417/410.1 |
International
Class: |
F04B 35/04 20060101
F04B035/04 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 31, 2010 |
JP |
2010-194456 |
Claims
1. A fuel pump comprising: a pump part that includes a rotation
member configured to suction and pressurize fuel; a motor part that
includes: a rotor coupled with a rotating shaft of the rotation
member to be capable of rotating the rotation member; a commutator
rotated together with the rotor to rectify an electric current
supplied to the rotor; and a housing accommodating the rotor and
the commutator; a motor casing that supports one end of the
rotating shaft of the rotation member; a motor cover that is
disposed at one end of the motor part in an axial direction thereof
and is fitted together with the housing so as to fix the motor
casing; a terminal that is disposed at an end portion of the motor
cover located on an opposite side from a fitted end of the motor
cover, which is fitted with the housing, the terminal being
electrically connectable to an external connector for electricity
supply; and an electric connector part that is disposed at the end
portion of the motor cover located on the opposite side from the
fitted end of the motor cover and that includes: a side surface
which is slidably in contact with the external connector to
determine a fitting position of the electric connector part
relative to the external connector; a bottom face from which the
terminal rises up; and an opening which is formed on the side
surface to communicate between inside and outside of the electric
connector part, wherein the bottom face is an inclined surface
whose height becomes lower in a direction from generally a center
of the motor cover toward the opening.
2. The fuel pump according to claim 1, wherein a gradient ratio of
an inclination of the inclined surface changes within the inclined
surface.
3. The fuel pump according to claim 1, wherein the bottom face
includes a groove in the direction from generally the center of the
motor cover toward the opening, the groove connecting to the
opening.
4. The fuel pump according to claim 3, wherein a height of a
recessed ridgeline of the groove becomes lower in the direction
from generally the center of the motor cover toward the
opening.
5. A fuel pump comprising: a pump part that includes a rotation
member configured to suction and pressurize fuel; a motor part that
includes: a rotor coupled with a rotating shaft of the rotation
member to be capable of rotating the rotation member; a commutator
rotated together with the rotor to rectify an electric current
supplied to the rotor; and a housing accommodating the rotor and
the commutator; a motor casing that supports one end of the
rotating shaft of the rotation member; a motor cover that is
disposed at one end of the motor part in an axial direction thereof
and is fitted together with the housing so as to fix the motor
casing; a terminal that is disposed at an end portion of the motor
cover located on an opposite side from a fitted end of the motor
cover, which is fitted with the housing, the terminal being
electrically connectable to an external connector for electricity
supply; and an electric connector part that is disposed at the end
portion of the motor cover located on the opposite side from the
fitted end of the motor cover and that includes: a side surface
which is slidly in contact with the external connector to determine
a fitting position of the electric connector part relative to the
external connector; a bottom face from which the terminal rises up;
and an opening which is formed on the side surface to communicate
between inside and outside of the electric connector part, wherein
the bottom face includes a groove in a direction from generally a
center of the motor cover toward the opening, the groove connecting
to the opening.
6. The fuel pump according to claim 5, wherein a height of a
recessed ridgeline of the groove becomes lower in the direction
from generally the center of the motor cover toward the opening.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is based on and incorporates herein by
reference Japanese Patent Application No. 2010-194456 filed on Aug.
31, 2010.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a fuel pump that drives its
pump part by driving force of its motor part to suction and
pressurize fuel.
[0004] 2. Description of Related Art
[0005] A fuel pump that supplies fuel to an internal combustion
engine is known. The fuel pump pressurizes fuel suctioned from a
fuel tank by its pump part, and supplies the fuel to the engine. In
the fuel pump, an electric current supplied via its electric
connector part flows through a coil, so that a rotor, around which
the coil is wound, rotates to drive the pump part. In
JP-A-2008-243569, by changing a shape of a resin member that
supports a terminal of an electric connector part, a corrosion or
short circuit of the terminal which is caused due to the residue of
fuel inside the electric connector part is prevented.
[0006] In the electrical connector described in JP-A-2008-243569,
an opening for discharging the fuel that remains in the electric
connector part into the outside is provided on a side surface of
the electric connector part. However, if fuel remains away from the
opening, or if the residual fuel becomes high-viscosity liquid as a
result of the evaporation of its volatile matter content, the
discharge of fuel from the opening becomes difficult, and they
remain inside the electric connector part. Particularly, because
the liquid, whose impure substance has been condensed due to the
evaporation of volatile matter content, exhibits high conductivity,
the terminal corrodes by a leak current between both poles, and
eventually damage of the terminal is caused.
SUMMARY OF THE INVENTION
[0007] The present invention addresses at least one of the above
disadvantages.
[0008] According to the present invention, there is provided a fuel
pump including a pump part, a motor part, a motor casing, a motor
cover, a terminal, and an electric connector part. The pump part
includes a rotation member configured to suction and pressurize
fuel. The motor part includes a rotor coupled with a rotating shaft
of the rotation member to be capable of rotating the rotation
member, a commutator rotated together with the rotor to rectify an
electric current supplied to the rotor, and a housing accommodating
the rotor and the commutator. The motor casing supports one end of
the rotating shaft of the rotation member. The motor cover is
disposed at one end of the motor part in an axial direction thereof
and is fitted together with the housing so as to fix the motor
casing. The terminal is disposed at an end portion of the motor
cover located on an opposite side from a fitted end of the motor
cover, which is fitted with the housing. The terminal is
electrically connectable to an external connector for electricity
supply. The electric connector part is disposed at the end portion
of the motor cover located on the opposite side from the fitted end
of the motor cover, and includes a side surface which is slidably
in contact with the external connector to determine a fitting
position of the electric connector part relative to the external
connector, a bottom face from which the terminal rises up, and an
opening which is formed on the side surface to communicate between
inside and outside of the electric connector part. The bottom face
is an inclined surface whose height becomes lower in a direction
from generally a center of the motor cover toward the opening.
[0009] According to the present invention, there is also provided a
fuel pump including a pump part, a motor part, a motor casing, a
motor cover, a terminal, and an electric connector part. The pump
part includes a rotation member configured to suction and
pressurize fuel. The motor part includes a rotor coupled with a
rotating shaft of the rotation member to be capable of rotating the
rotation member, a commutator rotated together with the rotor to
rectify an electric current supplied to the rotor, and a housing
accommodating the rotor and the commutator. The motor casing
supports one end of the rotating shaft of the rotation member. The
motor cover is disposed at one end of the motor part in an axial
direction thereof and is fitted together with the housing so as to
fix the motor casing. The terminal is disposed at an end portion of
the motor cover located on an opposite side from a fitted end of
the motor cover, which is fitted with the housing. The terminal is
electrically connectable to an external connector for electricity
supply. The electric connector part is disposed at the end portion
of the motor cover located on the opposite side from the fitted end
of the motor cover, and includes a side surface which is slidably
in contact with the external connector to determine a fitting
position of the electric connector part relative to the external
connector, a bottom face from which the terminal rises up, and an
opening which is formed on the side surface to communicate between
inside and outside of the electric connector part. The bottom face
includes a groove in a direction from generally a center of the
motor cover toward the opening, the groove connecting to the
opening.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The invention, together with additional objectives, features
and advantages thereof, will be best understood from the following
description, the appended claims and the accompanying drawings in
which:
[0011] FIG. 1 is a sectional view roughly illustrating a fuel pump
in accordance with a first embodiment of the invention;
[0012] FIG. 2 is a sectional view taken along a line II-II in FIG.
1 for illustrating enlarged vicinity of a brush;
[0013] FIG. 3A is a top view illustrating a motor cover of the fuel
pump in accordance with the first embodiment;
[0014] FIG. 3B is a front view of the motor cover viewed from a
direction of an arrow IIIB in FIG. 3A;
[0015] FIG. 3C is a sectional view taken along a line IIIC-IIIC in
FIG. 3A;
[0016] FIG. 4 is a sectional view taken along a line IV-IV in FIG.
3A for illustrating enlarged vicinity of a bottom face of an
electric connector part;
[0017] FIG. 5 is a perspective view of a cross-section taken along
a line V-V in FIG. 3B for illustrating the motor cover of the fuel
pump in accordance with the first embodiment;
[0018] FIG. 6A is a top view illustrating a motor cover of a fuel
pump in accordance with a second embodiment of the invention;
[0019] FIG. 6B is a front view of the motor cover viewed from a
direction of an arrow VIB in FIG. 6A;
[0020] FIG. 6C is a sectional view taken along a line VIC-VIC in
FIG. 6A; and
[0021] FIG. 7 is a sectional view taken along a line VII-VII in
FIG. 6A for illustrating enlarged vicinity of a bottom face of an
electric connector part.
DETAILED DESCRIPTION OF THE INVENTION
[0022] Embodiments of the invention will be described below with
reference to the accompanying drawings.
First Embodiment
[0023] A fuel pump 10 of a first embodiment of the invention is
illustrated in FIG. 1. This fuel pump 10 is an in-tank pump that is
disposed in a fuel tank (not shown) of a vehicle. The fuel pump 10
supplies fuel inside the fuel tank to an engine. The fuel pump 10
includes a pump part 12 that pressurizes the suctioned fuel, and a
motor part 14 that drives the pump part 12. The motor part 14 is a
direct-current motor with a brush. The fuel pump 10 includes a
housing 16 having a generally cylindrical shape. A permanent magnet
18 is disposed annularly in the circumferential direction on an
inner wall surface of the housing 16. A rotor 20 is disposed
radially inward of the permanent magnet 18 concentrically with the
annular permanent magnet 18.
[0024] The pump part 12 includes a casing main body 31, a casing
cover 32, and an impeller 33 which is a rotation member. The casing
main body 31 and the casing cover 32 define a generally C-shaped
pump passage 34. The impeller 33 is accommodated rotatably between
the casing main body 31 and the casing cover 32. The casing main
body 31 and the casing cover 32 are formed by, for example, die
casting of aluminum.
[0025] The casing main body 31 is fixed in one end side of the
housing 16 in an axial direction thereof by press fitting. A pump
part side bearing 35 that rotatably supports a shaft 21, which is
connected to the impeller 33, is disposed at a central part of the
casing main body 31.
[0026] The casing cover 32 is fixed to one end portion of the
housing 16 by calking, with the casing main body 31 covered in the
cover 32. A thrust bearing 36 that limits axial displacement of the
shaft 21 is fixed at a central part of the casing cover 32. The
casing cover 32 has a fuel inlet 38.
[0027] A motor casing 41 and a motor cover 42 are disposed at the
other end portion of the housing 16, i.e., on the opposite side of
the housing 16 from the casing main body 31 and the casing cover
32. The motor casing 41 is located between the motor cover 42 and
the housing 16. The motor casing 41 includes a connecting passage
44 that connects together a pump chamber 22 and a fuel passage 43
of the motor cover 42. The motor casing 41 defines a brush
accommodating chamber 45 which accommodates a brush 70 such that
the brush 70 can be reciprocated in its axial direction, as
illustrated in FIG. 2. The motor casing 41 defines the brush
accommodating chamber 45, in which the brush 70 is accommodated.
The motor casing 41 accommodates the brush 70, and a compression
spring 75 in its brush accommodating chamber 45.
[0028] As illustrated in FIG. 1, the motor cover 42 includes a fuel
discharge part 46 and an electric connector part 50 radially
outward of the shaft 21. The motor cover 42 is fixed to the housing
16 by calking. The fuel discharge part 46 includes the fuel passage
43 and a pressure regulating valve 48. The fuel passage 43 is
opened or closed by a valve member 49 of the pressure regulating
valve 48. When the pressure of fuel inside the fuel pump 10 becomes
larger than a predetermined value, the valve member 49 opens the
fuel passage 43.
[0029] Terminals 60, 61 are provided for the electric connector
part 50, which is connected to the outside of the fuel pump 10. As
illustrated in FIG. 2, the terminals 60, 61 are electrically
connected to a pigtail 71 via a choking coil 72 and a brush
terminal 73. The pigtail 71 is electrically connected to a side
surface of the surfaces, which constitute the brush 70, that is
located on the opposite side from a rotation center of the shaft
21.
[0030] As illustrated in FIG. 1, the rotor 20 is rotatably
accommodated inside the housing 16. One end portion of the shaft
21, which is integrated with the rotor 20, is rotatably supported
by the pump part side bearing 35 in its radial direction; and the
other end portion of the shaft 21 is rotatably supported by a motor
part side bearing 37 in the radial direction. A winding wire that
constitutes a coil 23 is wound around an outer peripheral surface
of the core 25, which is fixed to the shaft 21. A commutator 80 is
formed in the shape of a circular disk, and disposed above the
rotor 20. More specifically, the commutator 80 is located at an end
portion of the rotor 20 on its opposite side from the pump part
12.
[0031] The electric connector part 50 will be described in detail.
The electric connector part 50 is provided on the opposite side of
the center of the motor cover 42 from the fuel discharge part 46 as
illustrated in FIGS. 3A to 3C. The electric connector part 50 has a
recessed shape with a bottom because of its side surfaces 501, 502,
503, 504, which are slidably in contact with an external connector
for electricity supply to determine a fitting position between the
electricity supply connector and the electric connector part 50,
and its bottom face 505, from which from which the terminals 60, 61
are exposed to rise up. The electric connector part 50 is provided
with an opening 57 for the external connector, so as to be fitted
together to the external electricity supply connector. A direction
of the opening 57 for the external connector is an upward direction
which is the same direction as the direction of an opening of the
fuel discharge part 46. Arrows indicating the upward and downward
directions in FIGS. 3A to 4 illustrate upward and downward
directions with the fuel pump 10 disposed in the fuel tank.
[0032] As illustrated in FIG. 4, an interior portion of the
electric connector part 50 is divided into three parts: a terminal
part 51 and two communication parts 53, 55 by a shape of the bottom
face 505. The terminal part 51 is located at generally the center
of the electric connector part 50. A terminal part bottom face 52
that serves as a bottom face of the terminal part 51 is formed
generally parallel to a plane perpendicular to the upward and
downward directions. On the terminal part bottom face 52, the
terminals 60, 61 for receiving the electric power supply from the
outside are disposed at intervals to pass through the terminal part
bottom face 52 in the upward and downward directions.
[0033] The communication parts 53, 55 are formed at both ends of
the terminal part 51 in a tangential direction of the motor cover
42 to be connected to the terminal part 51. As illustrated in FIG.
3C, a communication part bottom face 54 serving as a bottom face of
the communication part 53 is an inclined surface from the center of
the motor cover 42 toward an opening 58. As well, a communication
part bottom face 56 serving as a bottom face of a communication
part 55 located on the opposite side of the terminal part 51 from
the communication part 53 is an inclined surface from the center of
the motor cover 42 toward an opening 59. Heights of the
communication part bottom faces 54, 56 become lower from the center
of the motor cover 42 toward the openings 58, 59. On the other
hand, height of the terminal part bottom face 52 does not change
regardless of its distance from the center of the motor cover 42 as
described above. Accordingly, as illustrated in FIG. 5, level
differences 531, 551 are formed respectively between the terminal
part bottom face 52 and the communication part bottom faces 54, 56.
Widths of the level differences 531, 551 become larger in a
direction away from the center of the motor cover 42.
[0034] As illustrated in FIG. 3B, the two generally rectangular
openings 58, 59 are formed on an outer wall of the electric
connector part 50. The openings 58, 59 communicate between the
inside and outside of the electric connector part 50. The openings
58, 59 are formed on radially outward extension lines of the
communication parts 53, 55, and the communication parts 53, 55 and
the openings 58, 59 are connected together. The openings 58, 59 are
formed such that the heights of the communication part bottom faces
54, 56, and heights of lower ends of the openings 58, 59 coincide
with each other.
[0035] Operation of the fuel pump 10 of the first embodiment will
be described. An electric current supplied to the terminal 60 from
a power source (not shown) is fed to the commutator 80 through the
brush terminal 73, the pigtail 71, and the brush 70. The electric
current fed into the commutator 80 is supplied to the coil 23 of
the rotor 20. Upon rotation of the rotor 20 by the electric current
supplied to the coil 23, the impeller 33 rotates together with the
rotor 20 and the shaft 21. When the impeller 33 rotates, fuel is
suctioned into the pump passage 34 through the fuel inlet 38. The
fuel suctioned into the pump passage 34 is discharged from the pump
passage 34 into the pump chamber 22 as a result of application of
kinetic energy to the fuel by vane grooves of the impeller 33. The
fuel discharged into the pump chamber 22 is supplied to the outside
of the fuel pump 10 through a surrounding area of the rotor 20 and
the fuel passage 43.
[0036] As a result of the increase of fuel in the fuel tank in the
electric connector part 50 with its opening 57 for the external
connector formed upward, a part of fuel enters into the electric
connector part 50. On the other hand, when a fluid level of fuel
decreases as a result of the consumption of fuel, the fuel, which
has entered into the electric connector part 50, moves from higher
bottom faces toward lower bottom faces along the communication part
bottom faces 54, 56 connected to the openings 58, 59, so as to be
discharged into the outside of the electric connector part 50.
[0037] Generally, fuel remains in an electric connector part due to
increase and decrease of fuel in a fuel tank. The residual fuel
becomes liquid containing many involatile impure substances as a
result of evaporation of its volatile matter content. The liquid
including many impure substances does not easily move inside the
electric connector part because of its high viscosity. Accordingly,
the liquid is not easily discharged even if there is an opening for
discharging the fuel, which has entered into the electric connector
part, into the outside.
[0038] In the fuel pump 10 of the first embodiment of the
invention, the communication part bottom faces 54, 56, whose
heights become lower outward in a radial direction of the motor
cover 42, are provided for the electric connector part 50. The
liquid including many impure substances that has remained inside
the electric connector part 50 moves toward the openings 58, 59
along the inclined surfaces of the communication part bottom faces
54, 56 by the action of gravity. Then, the liquid is discharged
into the outside of the electric connector part 50 through the
openings 58, 59. Accordingly, adhesion of impure substances
contained in the residual liquid to the terminals 60, 61 can be
prevented. As a result, development of corrosion of the terminals
60, 61, and eventually damage to the terminals 60, 61 can be
prevented.
Second Embodiment
[0039] A second embodiment of the invention will be described with
reference to FIGS. 5A to 7. The second embodiment is different from
the first embodiment in part of a shape of a communication part
bottom face that defines a communication part, which communicates
with a terminal part of an electric connector part. The same
numerals are used for indicating substantially the same components
as the first embodiment, and their descriptions are omitted. In the
second embodiment, communication part bottom faces 64, 66 defining
communication parts 63, 65 include grooves respectively.
Specifically, as illustrated in FIG. 7, V-shaped grooves are formed
on the communication part bottom faces 64, 66 such that their
recessed ridgelines 643, 663 are located in a downward direction.
The communication part bottom faces 64, 66 respectively include two
bottom faces, i.e., communication part center side bottom faces
641, 661 that are formed on a terminal part 51-side of the recessed
ridgelines 643, 663; and communication part outer side bottom faces
642, 662 that are formed toward two side walls 501, 502 which
constitute an electric connector part 50. Each two bottom faces are
inclined surfaces with the corresponding recessed ridgelines 643,
663 being the lowest points. Therefore, the communication part
center side bottom faces 641, 661, and the communication part outer
side bottom faces 642, 662 are connected together respectively at
the recessed ridgelines 643, 663.
[0040] Openings 68, 69 are connected to the V--shapes, which are
constituted of the communication part center side bottom faces 641,
661 and the communication part outer side bottom faces 642, 662.
Specifically, as illustrated in FIG. 6B, the V-shapes formed by the
communication part center side bottom faces 641, 661 and the
communication part outer side bottom faces 642, 662 coincide with
part of shapes of the openings 68, 69. Thus, the shapes of the
openings 68, 69 are generally pentagons respectively having one
vertex at their lowest positions.
[0041] In the second embodiment, liquid that remains in the
electric connector part 50 is collected at the recessed ridgelines
643, 663 along the inclined surfaces of the communication part
center side bottom faces 641, 661 and the communication part outer
side bottom faces 642, 662. After that, the collected liquid is
discharged into the outside of the electric connector part 50
through the openings 68, 69. Since the fuel that remains inside the
electric connector part 50 is gathered temporarily around the
recessed ridgelines 643, 663, even if the amount of remaining
liquid is small as compared with the first embodiment, the liquid
is easily discharged into the outside of the electric connector
part 50.
[0042] Modifications of the above embodiments will be described.
Firstly, in the above first embodiment, the shape of the
communication part bottom face is a planar inclined surface toward
the opening. Alternatively, the shape of the communication part
bottom face is not limited to this. The shape of the communication
part bottom face may be a curved surface having a conical shape, a
hemispherical shape, a radial shape, or the like; and a gradient
ratio of its inclination may be changed within this surface.
[0043] Secondly, in the above second embodiment, a groove formed on
the communication part bottom face is V-shaped at a generally
central position of the communication part bottom face. However,
the arrangement position of the groove, the shape of the groove,
the number of grooves, and height of a recessed ridgeline of the
groove are not necessarily limited to this.
[0044] Thirdly, in the above second embodiment, only the groove is
formed on the communication part bottom face. Alternatively, what
is formed on the communication part bottom face is not exclusive to
the groove. A communication part bottom face, on which the groove
is combined with the inclined surface described in the above first
embodiment, may be employed.
[0045] Fourthly, in the above embodiments, the inclined surface or
the groove is formed on the communication part bottom face.
However, a surface, on which the inclined surface or the groove is
formed, is not limited to the communication part bottom face. The
inclined surface or the groove may be formed also on the terminal
part bottom face, through which the terminal is disposed.
[0046] Fifthly, in the above embodiments, the height of the
communication part bottom face and the height of the lower end of
the opening are set to be the same. Alternatively, a positional
relationship between the communication part bottom face and the
opening is not necessarily limited to this. Any positional
relationship may be employed as long as the height of the
communication part bottom face is equal to or higher than the
height of the lower end of the opening.
[0047] Sixthly, in the above embodiments, the shape of the opening
is generally rectangular or generally pentagonal. However, the
shape of the opening is not limited to this. The shape of the
opening may be a shape that conforms with the shape of the
communication part bottom face, such as a generally round shape or
a generally polygon.
[0048] Lastly, in the above embodiments, the example of application
of the impeller having vane grooves to the rotation member of the
pump part is described. However, instead of the application of the
impeller, another type of a pump, such as a Trochoid (registered
trademark) pump or a gear pump, may be applied to the rotation
member.
[0049] The embodiments of application of the invention to the
in-tank pump disposed inside the fuel tank of the vehicle have been
described above. Nevertheless, the invention is not by any means
limited to such embodiments, and may be embodied in various modes
without departing from the scope of the invention.
[0050] To sum up, the fuel pump 10 of the above embodiments may be
described as follows.
[0051] The fuel pump 10 includes a pump part 12, a motor part 14, a
motor casing 41, a motor cover 42, a terminal 60 or 61, and an
electric connector part 50. The pump part 12 includes a rotation
member 33 configured to suction and pressurize fuel. The motor part
14 includes a rotor 20 coupled with a rotating shaft 21 of the
rotation member 33 to be capable of rotating the rotation member
33, a commutator 80 rotated together with the rotor 20 to rectify
an electric current supplied to the rotor 20, and a housing 16
accommodating the rotor 20 and the commutator 80. The motor casing
41 supports one end of the rotating shaft 21 of the rotation member
33. The motor cover 42 is disposed at one end of the motor part 14
in an axial direction thereof and is fitted together with the
housing 16 so as to fix the motor casing 41. The terminal 60 or 61
is disposed at an end portion of the motor cover 42 located on an
opposite side from a fitted end of the motor cover 42, which is
fitted with the housing 16. The terminal 60 or 61 is electrically
connectable to an external connector for electricity supply. The
electric connector part 50 is disposed at the end portion of the
motor cover 42 located on the opposite side from the fitted end of
the motor cover 42, and includes a side surface 501, 502, 503, or
504 which is slidably in contact with the external connector to
determine a fitting position of the electric connector part 50
relative to the external connector, a bottom face 54 or 56; 64 or
66 from which the terminal 60 or 61 rises up, and an opening 58 or
59; 68 or 69 which is formed on the side surface 501, 502, 503, or
504 to communicate between inside and outside of the electric
connector part 50. The bottom face 54 or 56; 64 or 66 is an
inclined surface whose height becomes lower in a direction from
generally a center of the motor cover 42 toward the opening 58 or
59; 68 or 69.
[0052] The bottom faces 54, 56 of the electric connector part 50
are inclined surfaces whose heights becomes lower from the
generally center of the motor cover 42 toward the openings 58, 59.
The liquid that remains inside the electric connector part 50 moves
toward the openings 58, 59 having lower heights along the inclined
surfaces formed on the bottom faces 54, 56 of the electric
connector part 50. Then, the liquid is discharged from the openings
58, 59 into the outside of the electric connector part 50.
Accordingly, corrosion of the terminals 60, 61 caused by adhesion
of impure substances contained in the residual liquid can be
prevented.
[0053] A gradient ratio of an inclination of the inclined surface
may change within the inclined surface. Specifically, the bottom
faces 54, 56 of the electric connector part 50 are not the inclined
surfaces having a certain gradient ratio in the whole regions
thereof. Alternatively, an arbitrary gradient ratio may be set at
an arbitrary position on each of the bottom faces 54, 56 of the
electric connector part 50. Consequently, by forming the inclined
surfaces 54, 56 having large gradient ratios at the positions at
which the liquid is more likely to remain, the residual liquid
easily moves to be collected. As a result, the corrosion of the
terminals 60, 61 due to attachments contained in the remaining
liquid can be prevented.
[0054] The bottom face 64 or 66 may include a groove in the
direction from generally the center of the motor cover 42 toward
the opening 68 or 69. The groove may connect to the opening 68 or
69. By the formation of grooves on the bottom faces 64, 66 of the
electric connector part 50 from the generally center of the motor
cover 42 toward the openings 68, 69, the liquid that remains inside
the electric connector part 50 can be collected at the lowest
portions 643, 663 of the grooves. After that, the liquid collected
at the lowest portions 643, 663 of the grooves is discharged into
the outside through their connecting openings 68, 69. Accordingly,
even if the amount of liquid remaining inside the electric
connector part 50 is small, the liquid is easily removed, and
corrosion of the terminals 60, 61 can be prevented.
[0055] A height of a recessed ridgeline 643 or 663 of the groove
may become lower in the direction from generally the center of the
motor cover 42 toward the opening 68 or 69. Consequently, the
liquid gathered at the recessed ridgelines 643, 663 of the grooves
moves toward the openings 68, 69 having lower heights, and is
discharged into the outside of the electric connector part 50. As a
result, the residual liquid can be efficiently discharged as
compared with the grooves whose recessed ridgelines 643, 663 have
constant heights.
[0056] Additional advantages and modifications will readily occur
to those skilled in the art. The invention in its broader terms is
therefore not limited to the specific details, representative
apparatus, and illustrative examples shown and described.
* * * * *